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  1. Cardiac output measurement

    Directory of Open Access Journals (Sweden)

    Andreja Möller Petrun

    2014-02-01

    Full Text Available In recent years, developments in the measuring of cardiac output and other haemodynamic variables are focused on the so-called minimally invasive methods. The aim of these methods is to simplify the management of high-risk and haemodynamically unstable patients. Due to the need of invasive approach and the possibility of serious complications the use of pulmonary artery catheter has decreased. This article describes the methods for measuring cardiac output, which are based on volume measurement (Fick method, indicator dilution method, pulse wave analysis, Doppler effect, and electrical bioimpedance.

  2. Measuring Cardiac Output during Cardiopulmonary Exercise Testing.

    Science.gov (United States)

    Vignati, Carlo; Cattadori, Gaia

    2017-07-01

    Cardiac output is a key parameter in the assessment of cardiac function, and its measurement is fundamental to the diagnosis, treatment, and prognostic evaluation of all heart diseases. Until recently, cardiac output determination during exercise had been only possible through invasive methods, which were not practical in the clinical setting. Because [Formula: see text]o 2 is cardiac output times arteriovenous content difference, evaluation of cardiac output is usually included in its measurement. Because of the difficulty of directly measuring peak exercise cardiac output, indirect surrogate parameters have been proposed, but with only modest clinical usefulness. Direct measurement of cardiac output can now be made by several noninvasive techniques, such as rebreathing inert gases, impedance cardiology, thoracic bioreactance, estimated continuous cardiac output technology, and transthoracic echocardiography coupled to cardiopulmonary exercise testing, which allow more definitive results and better understanding of the underlying physiopathology.

  3. Cardiac output during exercise

    DEFF Research Database (Denmark)

    Siebenmann, C; Rasmussen, P.; Sørensen, H.

    2015-01-01

    Several techniques assessing cardiac output (Q) during exercise are available. The extent to which the measurements obtained from each respective technique compares to one another, however, is unclear. We quantified Q simultaneously using four methods: the Fick method with blood obtained from...... the right atrium (Q(Fick-M)), Innocor (inert gas rebreathing; Q(Inn)), Physioflow (impedance cardiography; Q(Phys)), and Nexfin (pulse contour analysis; Q(Pulse)) in 12 male subjects during incremental cycling exercise to exhaustion in normoxia and hypoxia (FiO2  = 12%). While all four methods reported...... a progressive increase in Q with exercise intensity, the slopes of the Q/oxygen uptake (VO2) relationship differed by up to 50% between methods in both normoxia [4.9 ± 0.3, 3.9 ± 0.2, 6.0 ± 0.4, 4.8 ± 0.2 L/min per L/min (mean ± SE) for Q(Fick-M), Q(Inn), QP hys and Q(Pulse), respectively; P = 0...

  4. Cardiac output monitoring

    Directory of Open Access Journals (Sweden)

    Mathews Lailu

    2008-01-01

    Full Text Available Minimally invasive and non-invasive methods of estimation of cardiac output (CO were developed to overcome the limitations of invasive nature of pulmonary artery catheterization (PAC and direct Fick method used for the measurement of stroke volume (SV. The important minimally invasive techniques available are: oesophageal Doppler monitoring (ODM, the derivative Fick method (using partial carbon dioxide (CO 2 breathing, transpulmonary thermodilution, lithium indicator dilution, pulse contour and pulse power analysis. Impedance cardiography is probably the only non-invasive technique in true sense. It provides information about haemodynamic status without the risk, cost and skill associated with the other invasive or minimally invasive techniques. It is important to understand what is really being measured and what assumptions and calculations have been incorporated with respect to a monitoring device. Understanding the basic principles of the above techniques as well as their advantages and limitations may be useful. In addition, the clinical validation of new techniques is necessary to convince that these new tools provide reliable measurements. In this review the physics behind the working of ODM, partial CO 2 breathing, transpulmonary thermodilution and lithium dilution techniques are dealt with. The physical and the physiological aspects underlying the pulse contour and pulse power analyses, various pulse contour techniques, their development, advantages and limitations are also covered. The principle of thoracic bioimpedance along with computation of CO from changes in thoracic impedance is explained. The purpose of the review is to help us minimize the dogmatic nature of practice favouring one technique or the other.

  5. Comparing Methods for Cardiac Output

    DEFF Research Database (Denmark)

    Graeser, Karin; Zemtsovski, Mikhail; Kofoed, Klaus F

    2018-01-01

    tomography (CT) angiography. Sixty-two patients, scheduled for elective heart surgery, were included; 1 was subsequently excluded for logistic reasons. Inclusion criteria were coronary artery bypass surgery (N = 42) and aortic valve replacement (N = 19). Exclusion criteria were chronic atrial fibrillation...... of the left ventricular outflow tract. METHODS: The primary aim was a systematic comparison of CO with Doppler-derived 3D TEE and CO by thermodilution in a broad population of patients undergoing cardiac surgery. A subanalysis was performed comparing cross-sectional area by TEE with cardiac computed......, left ventricular ejection fraction below 0.40 and intracardiac shunts. Nineteen randomly selected patients had a cardiac CT the day before surgery. All images were stored for blinded post hoc analyses, and Bland-Altman plots were used to assess agreement between measurement methods, defined as the bias...

  6. Methods and apparatus for determining cardiac output

    Science.gov (United States)

    Cohen, Richard J. (Inventor); Mukkamala, Ramakrishna (Inventor); Sherman, Derin A. (Inventor)

    2010-01-01

    The present invention provides methods and apparatus for determining a dynamical property of the systemic or pulmonary arterial tree using long time scale information, i.e., information obtained from measurements over time scales greater than a single cardiac cycle. In one aspect, the invention provides a method and apparatus for monitoring cardiac output (CO) from a single blood pressure signal measurement obtained at any site in the systemic or pulmonary arterial tree or from any related measurement including, for example, fingertip photoplethysmography.According to the method the time constant of the arterial tree, defined to be the product of the total peripheral resistance (TPR) and the nearly constant arterial compliance, is determined by analyzing the long time scale variations (greater than a single cardiac cycle) in any of these blood pressure signals. Then, according to Ohm's law, a value proportional to CO may be determined from the ratio of the blood pressure signal to the estimated time constant. The proportional CO values derived from this method may be calibrated to absolute CO, if desired, with a single, absolute measure of CO (e.g., thermodilution). The present invention may be applied to invasive radial arterial blood pressure or pulmonary arterial blood pressure signals which are routinely measured in intensive care units and surgical suites or to noninvasively measured peripheral arterial blood pressure signals or related noninvasively measured signals in order to facilitate the clinical monitoring of CO as well as TPR.

  7. Cardiac output measurement instruments controlled by microprocessors

    International Nuclear Information System (INIS)

    Spector, M.; Barritault, L.; Boeri, C.; Fauchet, M.; Gambini, D.; Vernejoul, P. de

    The nuclear medicine and biophysics laboratory of the Necker-Enfants malades University Hospital Centre has built a microprocessor controlled Cardiac flowmetre. The principle of the cardiac output measurement from a radiocardiogram is well established. After injection of a radioactive indicator upstream from the heart cavities the dilution curve is obtained by the use of a gamma-ray precordial detector. This curve normally displays two peaks due to passage of the indicator into the right and left sides of the heart respectively. The output is then obtained from the stewart Hamilton principle once recirculation is eliminated. The graphic method used for the calculation however is long and tedious. The decreasing fraction of the dilution curve is projected in logarithmic space in order to eliminate recirculation by determining the mean straight line from which the decreasing exponential is obtained. The principle of the use of microprocessors is explained (electronics, logics) [fr

  8. Comparison of cardiac output measurement techniques

    DEFF Research Database (Denmark)

    Espersen, K; Jensen, E W; Rosenborg, D

    1995-01-01

    and CR, respectively, and TD were 2.5 +/- 2.2 and 2.6 +/- 1.6 l/min. The overall agreement between DOP and CR was 0.1 +/- 1.6 l/min. In conclusion, TD overestimated cardiac output compared to the other techniques and the poor agreement has to be taken into consideration especially in measures of low...

  9. Videodensitometric Methods for Cardiac Output Measurements

    Science.gov (United States)

    Mischi, Massimo; Kalker, Ton; Korsten, Erik

    2003-12-01

    Cardiac output is often measured by indicator dilution techniques, usually based on dye or cold saline injections. Developments of more stable ultrasound contrast agents (UCA) are leading to new noninvasive indicator dilution methods. However, several problems concerning the interpretation of dilution curves as detected by ultrasound transducers have arisen. This paper presents a method for blood flow measurements based on UCA dilution. Dilution curves are determined by real-time densitometric analysis of the video output of an ultrasound scanner and are automatically fitted by the Local Density Random Walk model. A new fitting algorithm based on multiple linear regression is developed. Calibration, that is, the relation between videodensity and UCA concentration, is modelled by in vitro experimentation. The flow measurement system is validated by in vitro perfusion of SonoVue contrast agent. The results show an accurate dilution curve fit and flow estimation with determination coefficient larger than 0.95 and 0.99, respectively.

  10. Videodensitometric Methods for Cardiac Output Measurements

    Directory of Open Access Journals (Sweden)

    Massimo Mischi

    2003-04-01

    Full Text Available Cardiac output is often measured by indicator dilution techniques, usually based on dye or cold saline injections. Developments of more stable ultrasound contrast agents (UCA are leading to new noninvasive indicator dilution methods. However, several problems concerning the interpretation of dilution curves as detected by ultrasound transducers have arisen. This paper presents a method for blood flow measurements based on UCA dilution. Dilution curves are determined by real-time densitometric analysis of the video output of an ultrasound scanner and are automatically fitted by the Local Density Random Walk model. A new fitting algorithm based on multiple linear regression is developed. Calibration, that is, the relation between videodensity and UCA concentration, is modelled by in vitro experimentation. The flow measurement system is validated by in vitro perfusion of SonoVue contrast agent. The results show an accurate dilution curve fit and flow estimation with determination coefficient larger than 0.95 and 0.99, respectively.

  11. Comparison of cardiac output measurement techniques

    DEFF Research Database (Denmark)

    Espersen, K; Jensen, E W; Rosenborg, D

    1995-01-01

    at a workload of 50 W (EX). The agreements between the techniques, two by two, were expressed as the bias calculated as the averaged differences between the techniques. Precision was expressed as the standard deviation of the bias. The overall agreement (bias +/- precision) between TD, DOP and CR respectively...... and CR, respectively, and TD were 2.5 +/- 2.2 and 2.6 +/- 1.6 l/min. The overall agreement between DOP and CR was 0.1 +/- 1.6 l/min. In conclusion, TD overestimated cardiac output compared to the other techniques and the poor agreement has to be taken into consideration especially in measures of low...

  12. Peripheral vasodilatation determines cardiac output in exercising humans

    DEFF Research Database (Denmark)

    Bada, A A; Svendsen, J H; Secher, N H

    2012-01-01

    In dogs, manipulation of heart rate has no effect on the exercise-induced increase in cardiac output. Whether these findings apply to humans remain uncertain, because of the large differences in cardiovascular anatomy and regulation. To investigate the role of heart rate and peripheral vasodilata...... demonstrate that the elevated cardiac output during steady-state exercise is regulated by the increase in skeletal muscle blood flow and venous return to the heart, whereas the increase in heart rate appears to be secondary to the regulation of cardiac output....... arterial ATP infusion at rest. Exercise and ATP infusion increased cardiac output, leg blood flow and vascular conductance (P ... vasodilatation in the regulation of cardiac output during steady-state exercise, we measured central and peripheral haemodynamics in 10 healthy male subjects, with and without atrial pacing (100–150 beats min(−1)) during: (i) resting conditions, (ii) one-legged knee extensor exercise (24 W) and (iii) femoral...

  13. Cardiac Output Calculation and Three-Dimensional Echocardiography

    NARCIS (Netherlands)

    Montealegre-Gallegos, Mario; Mahmood, Feroze; Owais, Khurram; Hess, Phillip; Jainandunsing, Jayant S.; Matyal, Robina

    Objective: To compare the determination of stroke volume (SV) and cardiac output (CO) using 2-dimensional (2D) versus 3-dimensional (3D) transesophageal echocardiography (TEE). Design: Prospective observational study. Setting: Tertiary care university hospital. Participants: 35 patients without

  14. Continuous cardiac output and mixed venous oxygen saturation monitoring.

    Science.gov (United States)

    Cariou, A; Monchi, M; Dhainaut, J F

    1998-12-01

    Continuous assessment of cardiac output and SVO2 in the critically ill may be helpful in both the monitoring variations in the patient's cardiovascular state and in determining the efficacy of therapy. Commercially available continuous cardiac output (CCO) monitoring systems are based on the pulsed warm thermodilution technique. In vitro validation studies have demonstrated that this method provides higher accuracy and greater resistance to thermal noise than standard bolus thermodilution techniques. Numerous clinical studies comparing bolus with continuous thermodilution techniques have shown this technique similarly accurate to track each other and to have negligible bias between them. The comparison between continuous thermal and other cardiac output methods also demonstrates good precision of the continuous thermal technique. Accuracy of continuous oximetry monitoring using reflectance oximetry via fiberoptics has been assessed both in vitro and in vivo. Most of the studies testing agreement between continuous SVO2 measurements and pulmonary arterial blood samples measured by standard oximetry have shown good correlation. Continuous SVO2 monitoring is often used in the management of critically ill patients. The most recently designed pulmonary artery catheters are now able to simultaneously measure either SVO2 and CCO or SVO2 and right ventricular ejection fraction. This ability to view simultaneous trends of SVO2 and right ventricular performance parameters will probably allow the clinician to graphically see the impact of volume loading or inotropic therapy over time, as well as the influence of multiple factors, including right ventricular dysfunction, on SVO2. However, the cost-effectiveness of new pulmonary artery catheters application remains still questionable because no established utility or therapeutic guidelines are available.

  15. Predictors of low cardiac output in decompensated severe heart failure

    Directory of Open Access Journals (Sweden)

    Marcelo Eidi Ochiai

    2011-01-01

    Full Text Available OBJECTIVE: To identify predictors of low cardiac output and mortality in decompensated heart failure. INTRODUCTION: Introduction: Patients with decompensated heart failure have a high mortality rate, especially those patients with low cardiac output. However, this clinical presentation is uncommon, and its management is controversial. METHODS: We studied a cohort of 452 patients hospitalized with decompensated heart failure with an ejection fraction of 60 years, and 64.6% were men. Low cardiac output was present in 281 (63% patients on admission. Chagas disease was the cause of heart failure in 92 (20.4% patients who had higher B type natriuretic peptide levels (1,978.38 vs. 1,697.64 pg/mL; P = 0.015. Predictors of low cardiac output were Chagas disease (RR: 3.655, P<0.001, lower ejection fraction (RR: 2.414, P<0.001, hyponatremia (RR: 1.618, P = 0.036, and renal dysfunction (RR: 1.916, P = 0.007. Elderly patients were inversely associated with low cardiac output (RR: 0.436, P = 0.001. Predictors of mortality were Chagas disease (RR: 2.286, P<0.001, ischemic etiology (RR: 1.449, P = 0.035, and low cardiac output (RR: 1.419, P = 0.047. CONCLUSIONS: In severe decompensated heart failure, predictors of low cardiac output are Chagas disease, lower ejection fraction, hyponatremia, and renal dysfunction. Additionally, Chagas disease patients have higher B type natriuretic peptide levels and a worse prognosis independent of lower ejection fraction.

  16. Cardiac output and blood volume parameters using femoral arterial thermodilution.

    Science.gov (United States)

    López-Herce, Jesús; Bustinza, Amaya; Sancho, Luis; Mencía, Santiago; Carrillo, Angel; Moral, Ramón; Bellón, Jose María

    2009-02-01

    The pulse-induced continuous cardiac output (PiCCO) system is a less invasive method than pulmonary thermodilution for the measurement of cardiac output and estimating blood volume parameters. The normal values in children have not been defined. The purpose of the present paper was therefore to evaluate cardiac output and parameters of blood volume using femoral arterial thermodilution in critically ill children. A prospective study was performed in 17 critically ill children aged between 2 months and 14 years. Two measurements were taken for each determination of cardiac output, global end diastolic volume (GEDVI), intrathoracic blood volume index (ITBI), extravascular lung water index (ELWI), systolic volume index (SVI), stroke volume variation (SVV), cardiac function index (CFI), left ventricular contractility (dp/dt max), and the systemic vascular resistance index (SVRI). One hundred and seventeen measurements were performed. The mean cardiac index (CI) was 3.5 +/- 1.3 L/min per m(2). The GEDVI (399.7 +/- 349.1 mL/m(2)), ITBI (574.5 +/- 212.2 mL/m(2)) and dp/dt max (804.6 +/- 372.1 mmHg/s) were lower than reported in adults, whereas ELWI (18.9 +/- 9.3 mL/m2) and CFI (8 +/- 2.5 L/min) where higher. The GEDVI, SVI, dp/dt max and CI increased with the weight of the patients whereas the ELWI values decreased. Femoral arterial thermodilution is a suitable technique for the measurement of cardiac output in critically ill children. The intrathoracic and intracardiac volumes are lower than in adults, whereas extrapulmonary water is higher; these values are related to the weight of the patient.

  17. Cardiac output and vasodilation in the vasovagal response

    DEFF Research Database (Denmark)

    Wieling, Wouter; Jardine, David L.; de Lange, Frederik J

    2016-01-01

    The simple faint is secondary to hypotension and bradycardia resulting in transient loss of consciousness. According to Ohm's law applied to the circulation, BP = SVR × CO, hypotension can result from a decrease in systemic vascular resistance (SVR), cardiac output (CO), or both. It is important...

  18. [PULSE WAVE TRANSIT TIME - ONE MORE ATTEMPT OF NON-INVASIVE CARDIAC OUTPUT MEASUREMENT.

    Science.gov (United States)

    Akselrod, B A; Tolstova, L A; Pshenichniy, T A; Fedulova, S V

    2017-09-01

    Estimated continuous cardiac output (esCCOTM) based on pulse wave transit time is one of alternative non-invasive CO measurement techniques. Randomized study included 23 scheduled patients operated upon due to cardiovascular diseases. Cardiac index (CI) was measured Comparative analyses of esCCO and others CO measurement methods used intraoperative was carried out. In the first group (n = 9) esCCO was compared with transpulmonary thermodilution (PiCCO-plus); in the second group (n = 8) - with pulmonary artery thermodilution; in the third group (n = 6) - with transoesophageal echocardiography (velocity-time integral). In the 1st group direct correlation was found (r = 0,773, p measurements were out of reference interval (more than ? 15%). Blend- Altman method showed the dispersion of results in all groups. 1. Estimated continuous cardiac output measurement technique based on PWTT has a direct correla- tion with prepulmonary thermodilution and transoesophageal echocardiography, medium and high power respectively. 2. esCCO has significant differences with the referential techniques during general anesthesia in cardiac surgery pa- tients. 3. Calibration based on invasive blood pressure and outside cardiac output measurement does not increase the accuracy of measurements. 4. esCCO has a negative diagnostic value and cannot be recommendedfor the cardiac out- put evaluation during cardiac surgery. 5. This method can be useful for analyze general effectiveness of perioperative hemodynamics.

  19. Noninvasive cardiac output measurement using bioreactance in postoperative pediatric patients.

    Science.gov (United States)

    Vergnaud, Estelle; Vidal, Charles; Verchere, Juliette Montmayeur; Taright, Hanna; Meyer, Philippe G; Carli, Pierre A; Orliaguet, Gilles A

    2015-02-01

    Thoracic bioreactance is a noninvasive and continuous method of cardiac output (CO) measurement that is being developed in adult patients. Very little information is available on thoracic bioreactance use in children. The aim of the study was to evaluate the ability of a bioreactance device (NICOM(®) ; Cheetah Medical, Tel Aviv, Israel) to estimate CO and to track changes in CO induced by volume expansion (VE) in children. Cardiac output values obtained using the NICOM(®) device (CONICOM ) and measured by trans-thoracic echocardiography (COTTE ) were compared in pediatric neurosurgical patients during the postoperative period. Seventy-three pairs of measurements of CO obtained in 30 children were available for analysis. The bias (lower and upper limits of agreement) between CONICOM and COTTE was -0.11 (-1.4 to 1.2) l·min(-1). The percentage error (PE) was 55%. The precision of the NICOM(®) device was 45%. A significant correlation was observed between the CO values obtained using the two methods (r = 0.89, icom induced by VE was 84% following exclusion of patients with changes in CO <15% (n = 5). The PE observed is too large, and the limits of agreement too wide, to enable us to comment on the equivalence of the two techniques of CO measurements. However, the NICOM(®) device performs well in tracking changes in CO following VE. © 2014 John Wiley & Sons Ltd.

  20. Systematic review of cardiac output measurements by echocardiography vs. thermodilution

    DEFF Research Database (Denmark)

    Wetterslev, Mik; Møller-Sørensen, Hasse; Johansen, Rasmus Rothmann

    2016-01-01

    PURPOSE: Echocardiography is frequently used in the hemodynamic evaluation of critically ill patients, but inaccurate measurements may lead to wrong clinical decisions. The aim of our systematic review was to investigate the interchangeability of echocardiography with thermodilution technique...... of the studies assessed left-sided heart structures and the majority had small bias, wide limits of agreement, and high percentage error between echocardiography and thermodilution. In only two of the 24 studies the precision of each technique (echocardiography and thermodilution) was assessed before comparing...... them. In the single study evaluating trending ability using valid methodology, agreement was observed between echocardiography and thermodilution in detecting the directional changes in cardiac output, but the magnitude of changes varied considerably. CONCLUSIONS: The majority of studies comparing...

  1. Cardiac output estimation using pulmonary mechanics in mechanically ventilated patients.

    Science.gov (United States)

    Sundaresan, Ashwath; Chase, J Geoffrey; Hann, Christopher E; Shaw, Geoffrey M

    2010-11-25

    The application of positive end expiratory pressure (PEEP) in mechanically ventilated (MV) patients with acute respiratory distress syndrome (ARDS) decreases cardiac output (CO). Accurate measurement of CO is highly invasive and is not ideal for all MV critically ill patients. However, the link between the PEEP used in MV, and CO provides an opportunity to assess CO via MV therapy and other existing measurements, creating a CO measure without further invasiveness.This paper examines combining models of diffusion resistance and lung mechanics, to help predict CO changes due to PEEP. The CO estimator uses an initial measurement of pulmonary shunt, and estimations of shunt changes due to PEEP to predict CO at different levels of PEEP. Inputs to the cardiac model are the PV loops from the ventilator, as well as the oxygen saturation values using known respiratory inspired oxygen content. The outputs are estimates of pulmonary shunt and CO changes due to changes in applied PEEP. Data from two published studies are used to assess and initially validate this model.The model shows the effect on oxygenation due to decreased CO and decreased shunt, resulting from increased PEEP. It concludes that there is a trade off on oxygenation parameters. More clinically importantly, the model also examines how the rate of CO drop with increased PEEP can be used as a method to determine optimal PEEP, which may be used to optimise MV therapy with respect to the gas exchange achieved, as well as accounting for the impact on the cardiovascular system and its management.

  2. Cardiac output estimation using pulmonary mechanics in mechanically ventilated patients

    Directory of Open Access Journals (Sweden)

    Hann Christopher E

    2010-11-01

    Full Text Available Abstract The application of positive end expiratory pressure (PEEP in mechanically ventilated (MV patients with acute respiratory distress syndrome (ARDS decreases cardiac output (CO. Accurate measurement of CO is highly invasive and is not ideal for all MV critically ill patients. However, the link between the PEEP used in MV, and CO provides an opportunity to assess CO via MV therapy and other existing measurements, creating a CO measure without further invasiveness. This paper examines combining models of diffusion resistance and lung mechanics, to help predict CO changes due to PEEP. The CO estimator uses an initial measurement of pulmonary shunt, and estimations of shunt changes due to PEEP to predict CO at different levels of PEEP. Inputs to the cardiac model are the PV loops from the ventilator, as well as the oxygen saturation values using known respiratory inspired oxygen content. The outputs are estimates of pulmonary shunt and CO changes due to changes in applied PEEP. Data from two published studies are used to assess and initially validate this model. The model shows the effect on oxygenation due to decreased CO and decreased shunt, resulting from increased PEEP. It concludes that there is a trade off on oxygenation parameters. More clinically importantly, the model also examines how the rate of CO drop with increased PEEP can be used as a method to determine optimal PEEP, which may be used to optimise MV therapy with respect to the gas exchange achieved, as well as accounting for the impact on the cardiovascular system and its management.

  3. Estimated venous return surface and cardiac output curve precisely predicts new hemodynamics after volume change.

    Science.gov (United States)

    Sugimachi, Masaru; Sunagawa, Kenji; Uemura, Kazunori; Kamiya, Atsunori; Shimizu, Shuji; Inagaki, Masashi; Shishido, Toshiaki

    2010-01-01

    In our extended Guyton's model, the ability of heart to pump blood is characterized by a cardiac output curve and the ability of vasculature to pool blood by a venous return surface. These intersect in a three-dimensional coordinate system at the operating right atrial pressure, left atrial pressure, and cardiac output. The baseline cardiac output curve and venous return surface and their changes after volume change would predict new hemodynamics. The invasive methods needed to precisely characterize cardiac output curve and venous return surface led us to aim at estimating cardiac output curve and venous return surface from a single hemodynamic measurement. Using the average values for two logarithmic function parameters, and for two slopes of a surface, we were able to estimate cardiac output curve and venous return surface. The estimated curve and surface predicted new hemodynamics after volume change precisely.

  4. Central venous oxygen saturation for the diagnosis of low cardiac output in septic shock patients

    DEFF Research Database (Denmark)

    Perner, A; Haase, N; Wiis, J

    2010-01-01

    Simple diagnostic tests are needed to screen septic patients for low cardiac output because intervention is recommended in these patients. We assessed the diagnostic value of central venous oxygen saturation in the superior vena cava (ScvO(2)) for detecting low cardiac output in patients with sep...... with septic shock.......Simple diagnostic tests are needed to screen septic patients for low cardiac output because intervention is recommended in these patients. We assessed the diagnostic value of central venous oxygen saturation in the superior vena cava (ScvO(2)) for detecting low cardiac output in patients...

  5. Central venous oxygen saturation for the diagnosis of low cardiac output in septic shock patients

    DEFF Research Database (Denmark)

    Perner, A; Haase, N; Wiis, J

    2010-01-01

    Simple diagnostic tests are needed to screen septic patients for low cardiac output because intervention is recommended in these patients. We assessed the diagnostic value of central venous oxygen saturation in the superior vena cava (ScvO(2)) for detecting low cardiac output in patients with sep......Simple diagnostic tests are needed to screen septic patients for low cardiac output because intervention is recommended in these patients. We assessed the diagnostic value of central venous oxygen saturation in the superior vena cava (ScvO(2)) for detecting low cardiac output in patients...

  6. Correlation Between the End-Tidal CO2 (EtCO2 and Decreased Cardiac Output Measured by Ultrasonic Cardiac Output Monitor (USCOM for Intubated Patients in ICU

    Directory of Open Access Journals (Sweden)

    Tjokorda Gde Agung Senopathi

    2017-01-01

    Full Text Available Background: assessment of cardiac output is crucial in management of critical ill patients. Various types of tool are available to measure cardiac output. However, most has limitations such as invasive, expensive, and require special skill. Assessment of End-tidal Carbon Dioxide (EtCO2 is expected to be used as an alternative estimation of cardiac output. It is based on the condition that when cardiac output is decreased, it decreased pulmonary blood flow and diffusion of CO2 into the alveolar, thereby increasing alveolar dead space and lowering EtCO2. Objective: to find a correlation between EtCO2 and decreased cardiac output measured by Ultrasonic Cardiac Output Monitor (USCOM for intubated patients in ICU of Sanglah General Hospital, Denpasar, Bali. Methods: This is a cross-sectional study, the correlation test conducted from June to August 2016 in ICU of Sanglah Hospital. The study involved 75 patients who eligible with a total population sampling technique. Intubated patients admitted to the ICU were evaluated for EtCO2 and USCOM in the first 24 hours by the researchers simultaneously. Shapiro-Francia test was used for normality and Pearson’s correlation tests was used to measure the correlations between variables. Results: The EtCO2 value obtained was positively correlated with cardiac output values (r = 0.373; p 0.001. Conclusion: there is a correlation between EtCO2 and decreased cardiac output measured by USCOM for intubated patients in ICU of Sanglah General Hospital, Denpasar

  7. Reference Values for Peak Exercise Cardiac Output in Healthy Individuals.

    Science.gov (United States)

    Agostoni, Piergiuseppe; Vignati, Carlo; Gentile, Piero; Boiti, Costanza; Farina, Stefania; Salvioni, Elisabetta; Mapelli, Massimo; Magrì, Damiano; Paolillo, Stefania; Corrieri, Nicoletta; Sinagra, Gianfranco; Cattadori, Gaia

    2017-06-01

    Cardiac output (Q˙) is a key parameter in the assessment of cardiac function, its measurement being crucial for the diagnosis, treatment, and prognostic evaluation of all heart diseases. Until recently, Q˙ determination at peak exercise has been possible through invasive methods, so that normal values were obtained in studies based on small populations. Nowadays, peak Q˙ can be measured noninvasively by means of the inert gas rebreathing (IGR) technique. The present study was undertaken to provide reference values for peak Q˙ in the normal general population and to obtain a formula able to estimate peak exercise Q˙ from measured peak oxygen uptake (V˙o 2 ). We studied 500 normal subjects (age, 44.9 ± 1.5 years; range, 18-77 years; 260 men, 240 women) who underwent a maximal cardiopulmonary exercise test with peak Q˙ measurement by IGR. In the overall study sample, peak Q˙ was 13.2 ± 3.5 L/min (men, 15.3 ± 3.3 L/min; women, 11.0 ± 2.0 L/min; P exercise was (4.4 × peak V˙o 2 ) + 4.3 in the overall study cohort, (4.3 × peak V˙o 2 ) + 4.5 in men, and (4.9 × peak V˙o 2 ) + 3.6 in women. The simultaneous measurement of Q˙ and V˙o 2 at peak exercise in a large sample of healthy subjects provided an equation to predict peak Q˙ from peak V˙o 2 values. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  8. Non-invasive cardiac output monitoring in neonates using bioreactance: a comparison with echocardiography.

    LENUS (Irish Health Repository)

    Weisz, Dany E

    2012-01-01

    Non-invasive cardiac output monitoring is a potentially useful clinical tool in the neonatal setting. Our aim was to evaluate a new method of non-invasive continuous cardiac output (CO) measurement (NICOM™) based on the principle of bioreactance in neonates.

  9. The normal ranges of cardiovascular parameters in children measured using the Ultrasonic Cardiac Output Monitor.

    Science.gov (United States)

    Cattermole, Giles N; Leung, P Y Mia; Mak, Paulina S K; Chan, Stewart S W; Graham, Colin A; Rainer, Timothy H

    2010-09-01

    The Ultrasonic Cardiac Output Monitor is a noninvasive method of hemodynamic assessment and monitoring in critically ill patients. There are no published reference ranges for normal values in children for this device. This study aimed to establish normal ranges for cardiovascular indices measured using Ultrasonic Cardiac Output Monitor in children aged 0-12 yrs old and to assess interobserver reliability. This was a population-based cross-sectional observational study. Schools and kindergartens in Hong Kong. Chinese children aged up to 12 yrs old. Two operators performed Ultrasonic Cardiac Output Monitor scans on each child together with standard oscillometric measurement of blood pressure and heart rate. Software intrinsic to the Ultrasonic Cardiac Output Monitor device produces values for stroke volume, cardiac output, and systemic vascular resistance. For each parameter, normal ranges were defined as lying between the 2.5th and 97.5th percentiles. Interobserver reliability was assessed with Bland-Altman plots, coefficients of variation, and intraclass correlation. A total of 1,197 Chinese children (55% boys) were scanned. Normal ranges of values for cardiac output, stroke volume, and systemic vascular resistance indices are presented. Interobserver reliability for Ultrasonic Cardiac Output Monitor was superior to that for standard blood pressure and heart rate measurement. This large study presents normal values for cardiovascular indices in children using the Ultrasonic Cardiac Output Monitor with good interobserver reliability.

  10. Cardiac output determined by echocardiography in patients with cirrhosis: comparison with the indicator dilution technique

    DEFF Research Database (Denmark)

    Andersen, Ulrik B; Møller, Søren; Bendtsen, Flemming

    2003-01-01

    BACKGROUND/AIMS: Measurement of cardiac output in hyperkinetic patients with cirrhosis by Doppler echocardiography is increasingly reported, but has not been validated. We have compared simultaneous measurements of cardiac output by Doppler echocardiography (CO(d)) and by the indicator dilution...

  11. RESPIRATION AND MEASUREMENT OF CARDIAC-OUTPUT BY THERMODILUTION AND CENTRAL OR PERIPHERAL DYE DILUTION

    NARCIS (Netherlands)

    DELHAAS, T; MOOK, GA; ZIJLSTRA, WG; BERGSTRA, A; VANDENMOLEN, H; NIJMEIJER, A; Schut, J.K.

    Cardiac output as measured by indicator dilution methods during artificial ventilation shows differences up to +/-35%. We studied the influence of spontaneous breathing on measurement of cardiac output by thermodilution (TD) and central (CDD) and peripheral dye dilution (PDD) in seven anesthetized

  12. Noninvasive cardiac output measurement by transthoracic electrical bioimpedence: influence of age and gender.

    Science.gov (United States)

    Sathyaprabha, Talakad N; Pradhan, Cauchy; Rashmi, G; Thennarasu, Kandavel; Raju, Trichur R

    2008-12-01

    Thoracic electrical bioimpedance (TEB) as a method of measuring cardiac output (CO) is being explored increasingly over the last two decades, as a non-invasive alternative to the pulmonary artery catheter. The objective of this study was to establish normative data for measurement of CO by TEB and define the effect of age and gender on CO. Stroke volume (SV) of 397 normal individuals (203 men, 194 women) in the age range of 10-77 years was determined using Kubisek and Bernstein formulae by TEB method. Derived cardiac parameters including CO, cardiac index (CI), systemic vascular resistance and resistance index were calculated and analyzed. We found significant difference in CO among age groups and between gender. CO between Kubicek formula and Bernstein formula correlated well, but their means differed significantly. Cardiac indices peak in the third and seventh decade and were comparable between genders. A comprehensive data set of normalized values expressed as 95% confidence interval and mean +/- SD in different age groups and different gender was possible for cardiac parameters using TEB.

  13. Immediate changes in estimated cardiac output and vascular resistance after 60Co exposure in monkeys: implication for performance decrement

    International Nuclear Information System (INIS)

    Bruner, A.

    1977-01-01

    Aortic blood flow velocity, blood pressure, and heart rate were recorded in 12 unanesthetized, nonperforming monkeys during exposure to 1000 rad 60 Co at 129--164 rad/min. The first postradiation changes were seen within 3--4 min of the exposure's start and included tachycardia, a transient hypotension secondary to a loss in peripheral resistance, and a brief increase followed by a decrease to subnormal levels in cardiac output. The lowest cardiac output occurred between 10 and 20 min postexposure while blood pressure and peripheral resistance were recovering. It was proposed that the concurrent combination of low cardiac output, low blood pressure, and supranormal peripheral resistance might sufficiently attenuate cerebral perfusion temporarily to account for the transient behavioral decrements often seen during this time. Histamine release was postulated as responsible for this vascular shock syndrome

  14. Multicenter study verifying a method of noninvasive continuous cardiac output measurement using pulse wave transit time: a comparison with intermittent bolus thermodilution cardiac output.

    Science.gov (United States)

    Yamada, Takashige; Tsutsui, Masato; Sugo, Yoshihiro; Sato, Tetsufumi; Akazawa, Toshimasa; Sato, Nobukazu; Yamashita, Koichi; Ishihara, Hironori; Takeda, Junzo

    2012-07-01

    Many technologies have been developed for minimally invasive monitoring of cardiac output. Estimated continuous cardiac output (esCCO) measurement using pulse wave transit time is one noninvasive method. Because it does not require any additional sensors other than those for conducting 3 basic forms of monitoring (electrocardiogram, pulse oximeter wave, and noninvasive (or invasive) arterial blood pressure measurement), esCCO measurement is potentially useful in routine clinical circulatory monitoring for any patient including low-risk patients. We evaluated the efficacy of noninvasive esCCO using pulse wave transit time in this multicenter study. We compared esCCO and intermittent bolus thermodilution cardiac output (TDCO) in 213 patients, 139 intensive care units (ICUs), and 74 operating rooms (ORs), at 7 participating institutions. We performed electrocardiogram, pulse oximetry, TDCO, and arterial blood pressure measurements in patients in ICUs and ORs; a single calibration was performed to measure esCCO continuously. TDCO measurement was performed once daily for ICU patients and every hour for OR patients, and just before the removal of the pulmonary arterial catheter from patients in both the ICU and OR. We evaluated esCCO against TDCO with correlation analysis and Bland and Altman analysis and also assessed the change of bias over time. Furthermore, we inspected the impact of change in systemic vascular resistance (SVR) on change in bias because abnormal SVR was assumed to be a factor contributing to the change of the bias. From among 588 esCCO and TDCO datasets (excluding calibration points), 587 datasets were analyzed for 213 patients. The analysis results show a correlation coefficient of 0.79 (P time intervals over 48 hours after calibration (repeated-measures analysis of variance P = 0.781) in the ICU. The influence of SVR on esCCO analysis showed a correlation coefficient between SVR and an error of 0.37 (P < 0.0001, 95% confidence interval 0

  15. Correlation of cardiac output and sevoflurane required to maintain anesthetic depth targeted with entropy index.

    Science.gov (United States)

    Bautin, Andrei E; Siganevich, Ann V; Malaya, Elena Y; Khomenko, Evgenii A; Gordeev, Mikhail L; Solntsev, Vladislav N

    2014-01-01

    We investigated the correlation of reduced cardiac output on required sevoflurane to maintain targeted anesthesia depth. 36 patients undergoing coronary artery bypass grafting with cardiopulmonary bypass were prospectively included in the study. Inspired sevoflurane concentration was adjusted to ensure state entropy index 2.2 l/min/m2 (1.37% ± 0.31%), P = 0.01. Relationship between CI and ETsev required for maintaining target level of anesthesia is non-linear. Patients with CI ≤ 2.2 l/min/m2 need lower levels of the ETsev for maintenance of the target anesthesia at an entropy index < 40.

  16. Lack of agreement and trending ability of the endotracheal cardiac output monitor compared with thermodilution

    DEFF Research Database (Denmark)

    Møller-Sørensen, H; Hansen, K L; Ostergaard, M

    2012-01-01

    BACKGROUND: Minimally invasive monitoring systems of central haemodynamics are gaining increasing popularity. The present study investigated the precision of the endotracheal cardiac output monitor (ECOM) system and its agreement with pulmonary artery catheter thermodilution (PAC TD) for measurin...

  17. Kredsløbsmonitorering med lithium dilution cardiac output-systemet

    DEFF Research Database (Denmark)

    Christiansen, Christian; Hostrup, Anette; Tønnesen, Else

    2008-01-01

    The lithium dilution cardiac output (LiDCO) system measures cardiac output beat-to-beat with high precision. The system is based on an arterial pulse power analysis which is calibrated every eight hours with a small non-pharmacological dose of lithium. The system is minimally invasive; it require...... only a peripheral arterial catheter and a venous access. Dynamic parameters for early goal-directed therapy are also provided. Udgivelsesdato: 2008-Feb-11...

  18. Haemodynamic changes during craniotomy monitored by a bioimpedance plethysmographic noninvasive cardiac output monitor.

    Science.gov (United States)

    Ali, Zulfiqar; Umamaheswara Rao, G S; Jaganath, A

    2009-06-01

    Profound cardiovascular changes may occur at various stages during a craniotomy. These changes require a detailed haemodynamic analysis including cardiac output. In the present study, we used a monitor based on electrical bioimpedance method for noninvasive cardiac output measurement. In 17 ASA I and II patients undergoing elective craniotomies for supratentorial tumours, the following haemodynamic parameters were measured noninvasively: heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), stroke volume (SV), cardiac output (CO) and systemic vascular resistance (SVR). Haemodynamic changes in response to the following events were studied: (a) induction of anaesthesia with thiopentone, (b) 15 min of air-O(2)-isoflurane anaesthesia, (c) infiltration of the scalp with lidocaine adrenaline mixture, and (d) change of inspired gas mixture to N(2)O-O(2)-isoflurane. HR increased (P < 0.001) and SV decreased (P < 0.001) while CO remained unchanged, one min after administration of thiopentone. After 15 min of isoflurane anaesthesia, HR increased (P < 0.001) and, SBP (P = 0.02), DBP (P = 0.002) and SV (P = 0.003) decreased significantly without change in CO. Three minutes after infiltration of the scalp with lidocaine-adrenaline mixture, there was an increase in SBP (P = 0.001), DBP (P = 0.007), SV (P = 0.007) and CO (P = 0.001) and a decrease in SVR (P < 0.001). Addition of nitrous oxide (60%) to the inspired gas mixture decreased SBP (P = 0.003) and DBP (P = 0.001) with a trend for decrease in CO (P < 0.1). The changes recorded in the present study conform to those that have been documented earlier by using invasive monitoring. Bioimpedance plethysmography is a useful noninvasive technique for monitoring and detailed analysis of the rapidly changing systemic haemodynamics during a craniotomy. The device could be useful for investigating important haemodynamic changes in specific neurosurgical settings.

  19. Determination of myocardial energetic output for cardiac rhythm pacing

    Czech Academy of Sciences Publication Activity Database

    Heřman, D.; Převorovská, Světlana; Maršík, František

    2007-01-01

    Roč. 7, č. 4 (2007), s. 156-161 ISSN 1567-8822 R&D Projects: GA ČR GA106/03/1073 Institutional research plan: CEZ:AV0Z20760514 Keywords : heart arrhythmia * cardiac pacing modes * numerical simulation Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery

  20. Comparison of arterial pressure cardiac output monitoring with transpulmonary thermodilution in septic patients.

    Science.gov (United States)

    Böettger, Simon F; Pavlovic, Dragan; Gründling, Matthias; Wendt, Michael; Hung, Orlando; Henzler, Dietrich; Kern, Hartmut Richard; Lehmann, Christian

    2010-03-01

    The measurement of cardiac output in critically ill patients is complicated by rapid pathophysiological changes. The aim of this study was to compare the recently developed Arterial Pressure Cardiac Output algorithm (APCO) with transpulmonary thermodilution (TDCO). Clinical and hemodynamic parameters were tested for their impact on the measurements. Twenty septic patients were examined. Cardiac output measurements were performed simultaneously on 3 consecutive days. The data were evaluated using regression analysis and the Bland Altman approach. Bland Altman analysis presented a bias of 0.72 L/min and limits of agreement of 2.16 to 3.61 L/min for TDCO vs. APCO. Statistically significant covariables in the regression analysis were systemic vascular resistance (pmeasurements with a minimally invasive approach and simple access to the patient's hemodynamic state. However, an underestimation at high cardiac output and an overestimation at low cardiac output relative to transpulmonary thermodilution were observed in septic patients. Therefore, the APCO algorithm in its current state cannot be substituted for transpulmonary thermodilution.

  1. Validation of noninvasive pulse contour cardiac output using finger arterial pressure in cardiac surgery patients requiring fluid therapy

    NARCIS (Netherlands)

    Hofhuizen, Charlotte; Lansdorp, Benno; van der Hoeven, Johannes G.; Scheffer, Gert-Jan; Lemson, Joris

    2014-01-01

    Introduction Nexfin (Edwards Lifesciences, Irvine, CA) allows for noninvasive continuous monitoring of blood pressure (ABPNI) and cardiac output (CONI) by measuring finger arterial pressure (FAP). To evaluate the accuracy of FAP in measuring ABPNI and CONI as well as the adequacy of detecting

  2. Validation of noninvasive pulse contour cardiac output using finger arterial pressure in cardiac surgery patients requiring fluid therapy

    NARCIS (Netherlands)

    Hofhuizen, C.M.; Lansdorp, B.; Hoeven, J.G. van der; Scheffer, G.J.; Lemson, J.

    2014-01-01

    INTRODUCTION: Nexfin (Edwards Lifesciences, Irvine, CA) allows for noninvasive continuous monitoring of blood pressure (ABPNI) and cardiac output (CONI) by measuring finger arterial pressure (FAP). To evaluate the accuracy of FAP in measuring ABPNI and CONI as well as the adequacy of detecting

  3. Constant infusion transpulmonary thermodilution for the assessment of cardiac output in exercising humans

    DEFF Research Database (Denmark)

    Calbet, J A L; Mortensen, Stefan; Munch, G D W

    2016-01-01

    To determine the accuracy and precision of constant infusion transpulmonary thermodilution cardiac output (CITT-Q) assessment during exercise in humans, using indocyanine green (ICG) dilution and bolus transpulmonary thermodilution (BTD) as reference methods, cardiac output (Q) was determined...... at rest and during incremental one- and two-legged pedaling on a cycle ergometer, and combined arm cranking with leg pedaling to exhaustion in 15 healthy men. Continuous infusions of iced saline in the femoral vein (n = 41) or simultaneously in the femoral and axillary (n = 66) veins with determination......: 6.1-11.1%). In conclusion, cardiac output can be precisely and accurately determined with constant infusion transpulmonary thermodilution in exercising humans....

  4. Noninvasive measurement of cardiac output during exercise by inert gas rebreathing technique.

    Science.gov (United States)

    Cattadori, Gaia; Schmid, Jean-Paul; Agostoni, Piergiuseppe

    2009-04-01

    Reduced exercise tolerance and dyspnea during exercise are hallmarks of heart failure syndrome. Exercise capacity and various parameters of cardiopulmonary response to exercise are of important prognostic value. All the available parameters only indirectly reflect left ventricular dysfunction and hemodynamic adaptation to an increased demand. Noninvasive assessment of cardiac output, especially during an incremental exercise stress test, would allow the direct measure of cardiac reserve and may become the gold standard for prognostic evaluation in the future.

  5. Validation of a new spectrometer for noninvasive measurement of cardiac output

    Science.gov (United States)

    Baum, Marc M.; Kumar, Sasi; Moss, John A.; Wagner, Peter D.

    2004-07-01

    Acetylene is a blood-soluble gas and for many years its uptake rate during rebreathing tests has been used to calculate the flow rate of blood through the lungs (normally equal to cardiac output) as well as the volume of lung tissue. A new, portable, noninvasive instrument for cardiac output determination using the acetylene uptake method is described. The analyzer relies on nondispersive IR absorption spectroscopy as its principle of operation and is configured for extractive (side-stream) sampling. The instrument affords exceptionally fast (30 ms, 10%-90%, 90%-10%, at 500 mL min-1 flow rates), interference-free, simultaneous measurement of acetylene, sulfur hexafluoride (an insoluble reference gas used in the cardiac output calculation), and carbon dioxide (to determine alveolar ventilation), with good (typically ±2% full-scale) signal-to-noise ratios. Comparison tests with a mass spectrometer using serially diluted calibration gas samples gave excellent (R2>0.99) correlation for all three gases, validating the IR system's linearity and accuracy. A similar level of agreement between the devices also was observed during human subject C2H2 uptake tests (at rest and under incremental levels of exercise), with the instruments sampling a common extracted gas stream. Cardiac output measurements by both instruments were statistically equivalent from rest to 90% of maximal oxygen consumption; the physiological validity of the measurements was confirmed by the expected linear relationship between cardiac output and oxygen consumption, with both the slope and intercept in the published range. These results indicate that the portable, low-cost, rugged prototype analyzer discussed here is suitable for measuring cardiac output noninvasively in a point-of-care setting.

  6. Biphasic cardiac output changes during onset of spinal anaesthesia in elderly patients

    DEFF Research Database (Denmark)

    Meyhoff, C S; Hesselbjerg, L; Koscielniak-Nielsen, Z

    2007-01-01

    ended when the patients were ready for surgery, or if ephedrine was given to raise the mean arterial pressure. RESULTS: Cardiac output increased initially reaching a maximum after a mean of 7 min. The average increase was 1.1 L min(-1) (P... mmHg on average. At the end of data collection, cardiac output decreased 0.5 L min(-1) from baseline (P=0.02). Mean arterial pressure decreased progressively in all patients, and only minimal changes in heart rate were found. CONCLUSIONS: Using this high time-resolution method, we detected biphasic...

  7. Correlation of cardiac output and sevoflurane required to maintain anesthetic depth targeted with entropy index

    Directory of Open Access Journals (Sweden)

    Andrei E Bautin

    2014-01-01

    Full Text Available Aims and Objectives: We investigated the correlation of reduced cardiac output on required sevoflurane to maintain targeted anesthesia depth. Materials and Methods: 36 patients undergoing coronary artery bypass grafting with cardiopulmonary bypass were prospectively included in the study. Inspired sevoflurane concentration was adjusted to ensure state entropy index 2.2 l/min/m 2 (1.37% ± 0.31%, P = 0.01. Conclusion: Relationship between CI and ETsev required for maintaining target level of anesthesia is non-linear. Patients with CI ≤ 2.2 l/min/m 2 need lower levels of the ETsev for maintenance of the target anesthesia at an entropy index < 40.

  8. Non-invasive measurement of cardiac output by Finometer in patients with cirrhosis

    DEFF Research Database (Denmark)

    Kaltoft, N; Hobolth, L; Møller, S

    2010-01-01

    The Finometer measures haemodynamic parameters including cardiac output (CO) using non-invasive volume-clamp techniques. The aim of this study was to determine the accuracy of the Finometer in hyperdynamic cirrhotic patients using an invasive indicator dilution technique as control. CO was measured...... in twenty-three patients referred for invasive measurements of the hepatic venous pressure gradient on suspicion of cirrhosis. Invasive measurements of CO were performed using indicator dilution technique (CO(I)) and simultaneous measurements of CO were recorded with the Finometer (CO(F)). In six patients......, measurements of CO were performed with invasive technique and the Finometer both before and after beta-blockade using 80 mg of propranolol and the changes in CO (DeltaCO(I) and DeltaCO(F) respectively) were calculated to evaluate the Finometers ability to detect relative changes in CO. Mean CO(I) was 6.1 +/- 1...

  9. Authentication of Radial Versus Femoral Arterial Pressure Waveform-Derived Cardiac Output With Transesophageal Echocardiography-Derived Cardiac Output Measurements in Patients Undergoing On-Pump Coronary Bypass Surgery.

    Science.gov (United States)

    Maddali, Madan Mohan; Waje, Niranjan Dilip; Sathiya, Panchatcharam Murthi

    2017-08-01

    The aim of this study was to ascertain if arterial waveform-derived cardiac output measurements from radial and femoral cannulation sites were reliable as compared with transesophageal echocardiography (TEE)-derived cardiac output (CO) values, and which of the CO measurements derived from radial and the femoral arterial pressure waveforms closely tracked simultaneously measured TEE-derived CO values. This study also aimed to ascertain if cardiopulmonary bypass (CPB) would impact the accuracy of arterial pressure-derived CO values from either of the 2 sites. A prospective observational study. Tertiary care cardiac center. Cardiac surgical patients undergoing on-pump primary coronary artery bypass surgery. Waveform-derived CO monitoring through radial and femoral artery cannulation using a FloTrac/Vigileo system. Twenty-seven consecutive cardiac surgical patients undergoing on-pump primary coronary artery bypass surgery were included in the study. Cardiac output was measured sequentially by the arterial pressure waveform analysis method from radial and femoral arterial sites and compared with simultaneously measured TEE-derived CO. Cardiac output data were obtained in triplicate at 6 predefined time intervals: before and after sternotomy, 5, 15, and 30 minutes after separation from CPB and prior to shifting the patient out of the operating room. The overall bias of the study was 0.11 and 0.27, the percentage error was 19.31 and 18.45, respectively, for radial and femoral arterial waveform-derived CO values as compared with TEE-derived CO measurements. The overall precision as compared with the TEE-derived CO values was 16.94 and 15.95 for the radial and femoral cannulation sites, respectively. The bias calculated by the Bland-Altman method suggested that CO measurements from the radial arterial site were in closer agreement with TEE-derived CO values at all time periods, and the relation was not affected by CPB. However, percentage error and precision calculations

  10. Management of perioperative low cardiac output state without extracorporeal life support: What is feasible?

    Directory of Open Access Journals (Sweden)

    Kumar Girish

    2010-01-01

    Full Text Available A transient and reversible reduction in cardiac output-low cardiac output state (LCOS often occurs following surgery for congenital heart disease. Inappropriately managed LCOS is a risk factor for increased morbidity and death. LCOS may occasionally be progressive and refractory needing a period of "myocardial rest" with extracorporeal life support (ECLS. ECLS is currently considered a routine tool available for rapid deployment in most industrialized countries. Accumulated experience and refinements in technology have led to improving survivals - discharge survivals of 35%−50%, with almost 100% survival in select groups on elective left ventricular assist device. Thus, there is an increasing trend to initiate ECLS "early or electively in the operating room" in high-risk patients. India has a huge potential need for ECLS given the large number of infants presenting late with preexisting ventricular dysfunction or in circulatory collapse. ECLS is an expensive and resource consuming treatment modality and is not a viable therapeutic option in our country. The purpose of this paper is to reiterate an anticipatory, proactive approach to LCOS: (1 methods for early detection of evolving LCOS and (2 timely initiation of individualized therapy. This paper also explores what is feasible with the refinement of "simple, conventional, inexpensive strategies" for the management of LCOS. Therapy for LCOS should be multimodal based on the type of circulation and physiology. Our approach to LCOS includes: (1 intraoperative strategies, (2 aggressive afterload reduction, (3 lusitropy, (4 exclusion of structural defects, (5 harnessing cardiopulmonary interactions, and (6 addressing metabolic and endocrine abnormalities. We have achieved a discharge survival rate of greater than 97% with these simple methods.

  11. Rowing increases stroke volume and cardiac output to a greater extent than cycling

    Czech Academy of Sciences Publication Activity Database

    Horn, P.; Ošťádal, P.; Ošťádal, Bohuslav

    2015-01-01

    Roč. 64, č. 2 (2015), s. 203-207 ISSN 0862-8408 Institutional support: RVO:67985823 Keywords : cardiac output * cycling * heart rate * stroke volume Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 1.643, year: 2015

  12. Transpulmonary thermodilution cardiac output measurement is not affected by severe pulmonary oedema: a newborn animal study

    NARCIS (Netherlands)

    Nusmeier, A.; Vrancken, S.L.; Boode, W.P. de; Hoeven, J.G. van der; Lemson, J.

    2013-01-01

    BACKGROUND: /st> The transpulmonary thermodilution (TPTD) technique is widely used in clinical practice for measuring cardiac output (CO). This study was designed to investigate the influence of various levels of pulmonary oedema on the reliability of CO measurements by the TPTD method. METHODS:

  13. A-V Delay Versus Cardiac Output Measured with Thorax Bioimpedance Monitor

    Czech Academy of Sciences Publication Activity Database

    Vondra, Vlastimil; Halámek, Josef; Viščor, Ivo; Jurák, Pavel; Novák, M.; Lipoldová, J.

    2008-01-01

    Roč. 6, č. 1 (2008), s. 73 ISSN 1556-7451. [World Congress on Heart Disease /14./. 26.07.2008-29.07.2008, Toronto] Institutional research plan: CEZ:AV0Z20650511 Keywords : atrio -ventricular delay * resynchronization therapy * impedance cardiography * cardiac output Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery

  14. Middle cerebral artery blood velocity depends on cardiac output during exercise with a large muscle mass

    NARCIS (Netherlands)

    Ide, K.; Pott, F.; van Lieshout, J. J.; Secher, N. H.

    1998-01-01

    We tested the hypothesis that pharmacological reduction of the increase in cardiac output during dynamic exercise with a large muscle mass would influence the cerebral blood velocity/perfusion. We studied the relationship between changes in cerebral blood velocity (transcranial Doppler), rectus

  15. Effect of Hemorrhage on Cardiac Output, PVP, Alodosterone and Diuresis during Immersion in Men

    Science.gov (United States)

    Simanonok, K.; Greenleaf, John E.; Bernauer, E. M.; Wade, C. E.; Keil, L. C.

    1990-01-01

    The purpose of this study was to test the hypothesis that a reduction in blood volume would attenuate or eliminate immersion-induced increases in cardiac output (Q (sup dot) sub co)) and urine excretion, and to investigate accompanying vasoactive and fluid-electrolyte hormonal responses.

  16. Cardiac output and vasodilation in the vasovagal response: An analysis of the classic papers

    NARCIS (Netherlands)

    Wieling, Wouter; Jardine, David L.; de Lange, Frederik J.; Brignole, Michele; Nielsen, Henning B.; Stewart, Julian; Sutton, Richard

    2016-01-01

    The simple faint is secondary to hypotension and bradycardia resulting in transient loss of consciousness. According to Ohm's law applied to the circulation, BP = SVR × CO, hypotension can result from a decrease in systemic vascular resistance (SVR), cardiac output (CO), or both. It is important to

  17. Resistance training improves cardiac output, exercise capacity and tolerance to positive airway pressure in Fontan physiology.

    Science.gov (United States)

    Cordina, Rachael L; O'Meagher, Shamus; Karmali, Alia; Rae, Caroline L; Liess, Carsten; Kemp, Graham J; Puranik, Raj; Singh, Nalin; Celermajer, David S

    2013-09-30

    Subjects with Fontan-type circulation have no sub-pulmonary ventricle and thus depend exquisitely on the respiratory bellows and peripheral muscle pump for cardiac filling. We hypothesised that resistance training to augment the peripheral muscle pump might improve cardiac filling, reduce inspiratory-dependence of IVC return to the heart and thus improve exercise capacity and cardiac output on constant positive airway pressure (CPAP). Eleven Fontan subjects (32+/-2 years, mean+/-SEM) had cardiac magnetic resonance imaging (MRI) and exercise testing (CPET); six underwent 20 weeks of high-intensity resistance training; others were non-exercising controls. After training, CPET was repeated. Four trainers had MRI with real-time flow measurement at rest, exercise and on CPAP in the trained state and following a 12-month detrain. In the trained state, muscle strength increased by 43% (p=0.002), as did total muscle mass (by 1.94 kg, p=0.003) and peak VO2 (by 183 ml/min, p=0.02). After detraining, calf muscle mass and peak workload had fallen significantly (pexercise (by 16 ml, p=0.04); inspiratory-dependent IVC blood return during exercise was 40% higher (p=0.02). On CPAP, cardiac output was lower in the detrained state (101 vs. 77 ml/s, p=0.03). Resistance muscle training improves muscle mass, strength and is associated with improved cardiac filling, stroke volume, exercise capacity and cardiac output on CPAP, in adults with Fontan-type circulation. Crown Copyright © 2012. Published by Elsevier Ireland Ltd. All rights reserved.

  18. Effects of Exercise Training on Haematology and Maximal Cardiac Output

    DEFF Research Database (Denmark)

    Bonne, Thomas Christian

    to the heart ultra structure possibly also play a role for improving Qmax. Other mechanisms that can improve exercise capacity include hypoxia. It is universally accepted that hypoxia is a main stimulant of erythropoiesis and altitude training is considered a possibility to increase red blood cell volume...... and hence exercise performance in elite athletes. However, the efficacy of altitude training for sea level performance is still debated and the literature is divergent on this matter. Even if the haematological changes following altitude training may be inadequate to substantially improve performance...... altitude training camp on Hbmass and VO2max were studied in 10 Olympic swimmers. Ten swimmers of comparable characteristics were chosen for a sea level control group. Both the altitude and sea level group completed a similar training intervention at either altitude or sea level. Hbmass significantly...

  19. Accuracy of Cardiac Output by Nine Different Pulse Contour Algorithms in Cardiac Surgery Patients: A Comparison with Transpulmonary Thermodilution.

    Science.gov (United States)

    Broch, Ole; Bein, Berthold; Gruenewald, Matthias; Masing, Sarah; Huenges, Katharina; Haneya, Assad; Steinfath, Markus; Renner, Jochen

    2016-01-01

    Objective. Today, there exist several different pulse contour algorithms for calculation of cardiac output (CO). The aim of the present study was to compare the accuracy of nine different pulse contour algorithms with transpulmonary thermodilution before and after cardiopulmonary bypass (CPB). Methods. Thirty patients scheduled for elective coronary surgery were studied before and after CPB. A passive leg raising maneuver was also performed. Measurements included CO obtained by transpulmonary thermodilution (CO TPTD ) and by nine pulse contour algorithms (CO X1-9 ). Calibration of pulse contour algorithms was performed by esophageal Doppler ultrasound after induction of anesthesia and 15 min after CPB. Correlations, Bland-Altman analysis, four-quadrant, and polar analysis were also calculated. Results. There was only a poor correlation between CO TPTD and CO X1-9 during passive leg raising and in the period before and after CPB. Percentage error exceeded the required 30% limit. Four-quadrant and polar analysis revealed poor trending ability for most algorithms before and after CPB. The Liljestrand-Zander algorithm revealed the best reliability. Conclusions. Estimation of CO by nine different pulse contour algorithms revealed poor accuracy compared with transpulmonary thermodilution. Furthermore, the less-invasive algorithms showed an insufficient capability for trending hemodynamic changes before and after CPB. The Liljestrand-Zander algorithm demonstrated the highest reliability. This trial is registered with NCT02438228 (ClinicalTrials.gov).

  20. Risk for decreased cardiac output: validation of a proposal for nursing diagnosis.

    Science.gov (United States)

    Pereira de Melo, Renata; Venícios de Oliveira Lopes, Marcos; Leite de Araujo, Thelma; de Fatima da Silva, Lucia; Aline Arrais Sampaio Santos, Francisca; Moorhead, Sue

    2011-01-01

    To verify the content validity of the nursing diagnosis risk for decreased cardiac output (RDCO). DCO is a phenomenon that is not restricted to individuals or environments that specifically focus on cardiovascular care. It is not only prevalent in cardiovascular care units, but also in post-anaesthesia units and non-cardiac care units among individuals with non-cardiogenic disorders. A significant decrease in cardiac output is a life-threatening situation, demonstrating the need for developing a risk nursing diagnosis for early intervention. The development of this diagnosis requires the construction of a diagnosis label, a definition of the diagnostic concept and the risk factors associated with the diagnosis. The research was carried out in two methodological stages based on the Fehring diagnosis content validation model. The quantitative analysis consisted of the calculation of the weighted mean of the values attributed by experts to each risk factor, the level of agreement/disagreement between the experts regarding the operational definitions of risk factors and the index of diagnostic content validity (DCV). The label 'risk for decreased cardiac output' was considered representative of a nursing diagnosis defined as 'at risk of developing a health status characterized by an insufficient quantity of blood pumped by the heart to meet physical metabolic demands'. Critical risk factors (DCV ≥ 0·7) were myocardial dysfunction (0·887), blood loss (0·875), increase in intrapericardial pressure (0·825), condition that leads to changes in cardiac rhythm and/or electrical conduction (0·812), deficient fluid volume (0·725), plasma loss (0·712), ineffective tissue perfusion (0·712) and electrolyte imbalance (0·7). The research identified eight risk factors with valid content for assessment of RDCO. The identification of risk factors for DCO assists nurses to intervene early and minimize the consequences of a deficient cardiac function. © 2011 The Authors

  1. Arterial pressure-based cardiac output in septic patients: different accuracy of pulse contour and uncalibrated pressure waveform devices

    OpenAIRE

    Monnet, Xavier; Anguel, Nadia; Naudin, Brice; Jabot, Julien; Richard, Christian; Teboul, Jean-Louis

    2010-01-01

    Introduction We compared the ability of two devices estimating cardiac output from arterial pressure-curve analysis to track the changes in cardiac output measured with transpulmonary thermodilution induced by volume expansion and norepinephrine in sepsis patients. Methods In 80 patients with septic circulatory failure, we administered volume expansion (40 patients) or introduced/increased norepinephrine (40 patients). We measured the pulse contour-derived cardiac index (CI) provided by the P...

  2. CMR fluoroscopy right heart catheterization for cardiac output and pulmonary vascular resistance: results in 102 patients.

    Science.gov (United States)

    Rogers, Toby; Ratnayaka, Kanishka; Khan, Jaffar M; Stine, Annette; Schenke, William H; Grant, Laurie P; Mazal, Jonathan R; Grant, Elena K; Campbell-Washburn, Adrienne; Hansen, Michael S; Ramasawmy, Rajiv; Herzka, Daniel A; Xue, Hui; Kellman, Peter; Faranesh, Anthony Z; Lederman, Robert J

    2017-07-27

    Quantification of cardiac output and pulmonary vascular resistance (PVR) are critical components of invasive hemodynamic assessment, and can be measured concurrently with pressures using phase contrast CMR flow during real-time CMR guided cardiac catheterization. One hundred two consecutive patients underwent CMR fluoroscopy guided right heart catheterization (RHC) with simultaneous measurement of pressure, cardiac output and pulmonary vascular resistance using CMR flow and the Fick principle for comparison. Procedural success, catheterization time and adverse events were prospectively collected. RHC was successfully completed in 97/102 (95.1%) patients without complication. Catheterization time was 20 ± 11 min. In patients with and without pulmonary hypertension, baseline mean pulmonary artery pressure was 39 ± 12 mmHg vs. 18 ± 4 mmHg (p < 0.001), right ventricular (RV) end diastolic volume was 104 ± 64 vs. 74 ± 24 (p = 0.02), and RV end-systolic volume was 49 ± 30 vs. 31 ± 13 (p = 0.004) respectively. 103 paired cardiac output and 99 paired PVR calculations across multiple conditions were analyzed. At baseline, the bias between cardiac output by CMR and Fick was 5.9% with limits of agreement -38.3% and 50.2% with r = 0.81 (p < 0.001). The bias between PVR by CMR and Fick was -0.02 WU.m 2 with limits of agreement -2.6 and 2.5 WU.m 2 with r = 0.98 (p < 0.001). Correlation coefficients were lower and limits of agreement wider during physiological provocation with inhaled 100% oxygen and 40 ppm nitric oxide. CMR fluoroscopy guided cardiac catheterization is safe, with acceptable procedure times and high procedural success rate. Cardiac output and PVR measurements using CMR flow correlated well with the Fick at baseline and are likely more accurate during physiological provocation with supplemental high-concentration inhaled oxygen. Clinicaltrials.gov NCT01287026 , registered January 25, 2011.

  3. Evaluation of Resting Cardiac Power Output as a Prognostic Factor in Patients with Advanced Heart Failure.

    Science.gov (United States)

    Yildiz, Omer; Aslan, Gamze; Demirozu, Zumrut T; Yenigun, Cemal Deniz; Yazicioglu, Nuran

    2017-09-15

    If the heart is represented by a hydraulic pump, cardiac power represents the hydraulic function of the heart. Cardiac pump function is frequently determined through left ventricular ejection fraction using imaging. This study aims to validate resting cardiac power output (CPO) as a predictive biomarker in patients with advanced heart failure (HF). One hundred and seventy-two patients with HF severe enough to warrant cardiac transplantation were retrospectively reviewed at a single tertiary care institution between September 2010 and July 2013. Patients were initially evaluated with simultaneous right-sided and left-sided cardiac catheter-based hemodynamic measurements, followed by longitudinal follow-up (median of 52 months) for adverse events (cardiac mortality, cardiac transplantation, or ventricular assist device placement). Median resting CPO was 0.54 W (long rank chi-square = 33.6; p < 0.0001). Decreased resting CPO (<0.54 W) predicted increased risk for adverse outcomes. Fifty cardiac deaths, 10 cardiac transplants, and 12 ventricular assist device placements were documented. The prognostic relevance of resting CPO remained significant after adjustment for age, gender, left ventricular ejection fraction, mean arterial pressure, pulmonary vascular resistance, right atrial pressure, and estimated glomerular filtration rate (HR, 3.53; 95% confidence interval, 1.66 to 6.77; p = 0.0007). In conclusion, lower resting CPO supplies independent prediction of adverse outcomes. Thus, it could be effectively used for risk stratification in patients with advanced HF. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Is pulmonary gas exchange during exercise in hypoxia impaired with the increase of cardiac output?

    DEFF Research Database (Denmark)

    Calbet, J.A.; Robach, P.; Lundby, C.

    2008-01-01

    During exercise in humans, the alveolar-arterial O(2) tension difference ((A-a)DO(2)) increases with exercise intensity and is an important factor determining the absolute level of oxygen binding to hemoglobin and therefore the level of systemic oxygen transport. During exercise in hypoxia, the (A......-a)DO(2) is accentuated. Using the multiple inert gas elimination technique it has been shown that during exercise in acute hypoxia the contribution of ventilation-perfusion inequality to (A-a)DO(2) is rather small and in the absence of pulmonary edema intrapulmonary shunts can be ruled out. This implies...... that the main mechanism limiting pulmonary gas exchange is diffusion limitation. It is presumed that an elevation of cardiac output during exercise in acute hypoxia should increase the (A-a)DO(2). However, no studies have examined how variations in cardiac output independently affect pulmonary diffusion...

  5. Management of perioperative low cardiac output state without extracorporeal life support: What is feasible?

    International Nuclear Information System (INIS)

    Kumar, Girish; Iyer, Parvathi U

    2010-01-01

    A transient and reversible reduction in cardiac output–low cardiac output state (LCOS) often occurs following surgery for congenital heart disease. Inappropriately managed LCOS is a risk factor for increased morbidity and death. LCOS may occasionally be progressive and refractory needing a period of “myocardial rest” with extracorporeal life support (ECLS). ECLS is currently considered a routine tool available for rapid deployment in most industrialized countries. Accumulated experience and refinements in technology have led to improving survivals – discharge survivals of 35%–50%, with almost 100% survival in select groups on elective left ventricular assist device. Thus, there is an increasing trend to initiate ECLS “early or electively in the operating room” in high-risk patients. India has a huge potential need for ECLS given the large number of infants presenting late with preexisting ventricular dysfunction or in circulatory collapse. ECLS is an expensive and resource consuming treatment modality and is not a viable therapeutic option in our country. The purpose of this paper is to reiterate an anticipatory, proactive approach to LCOS: (1) methods for early detection of evolving LCOS and (2) timely initiation of individualized therapy. This paper also explores what is feasible with the refinement of “simple, conventional, inexpensive strategies” for the management of LCOS. Therapy for LCOS should be multimodal based on the type of circulation and physiology. Our approach to LCOS includes: (1) intraoperative strategies, (2) aggressive afterload reduction, (3) lusitropy, (4) exclusion of structural defects, (5) harnessing cardiopulmonary interactions, and (6) addressing metabolic and endocrine abnormalities. We have achieved a discharge survival rate of greater than 97% with these simple methods

  6. Levosimendan in a neonate with severe coarctation of aorta and low cardiac output syndrome

    Directory of Open Access Journals (Sweden)

    Yann Olivier Boegli

    2013-01-01

    Full Text Available We report successful use of levosimendan after failed balloon angioplasty in a critically ill neonate with coarctation of aorta (CoA and severe low cardiac output syndrome (LCOS. Treatment with levosimendan improved left heart function, and decreased lactate and brain natriuretic peptide levels. To our knowledge, this is the first report on the safe and successful use of levosimendan in the management of LCOS due to severe CoA in a neonate awaiting surgical repair.

  7. Measurements of cardiac output obtained with transesophageal echocardiography and pulmonary artery thermodilution are not interchangeable

    DEFF Research Database (Denmark)

    Møller-Sørensen, H; Graeser, K; Hansen, K L

    2014-01-01

    BACKGROUND: Echocardiography is increasingly becoming an integrated tool for circulatory evaluation in the intensive care unit and the operating room. Therefore, it is imperative to know the reproducibility of measurements obtained by echocardiography. In this study, a comparison of cardiac output...... (CO) measurements obtained with transesophageal echocardiography (TEE) and pulmonary artery catheter (PAC) thermodilution (TD) was carried out to test the precision, accuracy and trending ability of CO measurements obtained with TEE. METHODS: Twenty-five patients completed the study. Each patient...

  8. The accuracy of PiCCO® in measuring cardiac output in patients under therapeutic hypothermia: Comparison with transthoracic echocardiography.

    Science.gov (United States)

    Souto Moura, T; Aguiar Rosa, S; Germano, N; Cavaco, R; Sequeira, T; Alves, M; Papoila, A L; Bento, L

    2018-03-01

    Invasive cardiac monitoring using thermodilution methods such as PiCCO® is widely used in critically ill patients and provides a wide range of hemodynamic variables, including cardiac output (CO). However, in post-cardiac arrest patients subjected to therapeutic hypothermia, the low body temperature possibly could interfere with the technique. Transthoracic Doppler echocardiography (ECHO) has long proved its accuracy in estimating CO, and is not influenced by temperature changes. To assess the accuracy of PiCCO® in measuring CO in patients under therapeutic hypothermia, compared with ECHO. Thirty paired COECHO/COPiCCO measurements were analyzed in 15 patients subjected to hypothermia after cardiac arrest. Eighteen paired measurements were obtained at under 36°C and 12 at ≥36°C. A value of 0.5l/min was considered the maximum accepted difference between the COECHO and COPiCCO values. Under conditions of normothermia (≥36°C), the mean difference between COECHO and COPiCCO was 0.030 l/min, with limits of agreement (-0.22, 0.28) - all of the measurements differing by less than 0.5 l/min. In situations of hypothermia (<36°C), the mean difference in CO measurements was -0.426 l/min, with limits of agreement (-1.60, 0.75), and only 44% (8/18) of the paired measurements fell within the interval (-0.5, 0.5). The calculated temperature cut-off point maximizing specificity was 35.95°C: above this temperature, specificity was 100%, with a false-positive rate of 0%. The results clearly show clinically relevant discordance between COECHO and COPiCCO at temperatures of <36°C, demonstrating the inaccuracy of PiCCO® for cardiac output measurements in hypothermic patients. Copyright © 2017 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

  9. High Output Cardiac Failure Resolving after Repair of AV Fistula in a Six-Month-Old

    Directory of Open Access Journals (Sweden)

    Uygar Teomete

    2016-01-01

    Full Text Available Background. Acquired AVF in pediatrics are commonly caused by iatrogenic means, including arterial or venous punctures. These fistulae can cause great hemodynamic stress on the heart as soon as they are created. Case. A six-month-old 25-week gestation infant was referred for respiratory distress. Initial exam revealed tachypnea, tachycardia, and hypertension. There was a bruit noted on her left arm. An ultrasound showed an arteriovenous fistula. Its location, however, precluded intervention because of the high risk for limb-loss. An echocardiogram showed evidence of pulmonary hypertension that was treated with sildenafil and furosemide. However, no improvement was seen. On temporary manual occlusion of the fistula, the patient was noted to have increased her blood pressure and decreased her heart rate, suggesting significant hemodynamic effect of the fistula. The fistula was subsequently ligated and the patient clinically and echocardiographically improved. Conclusion. A patient in high output cardiac failure or pulmonary artery hypertension, especially prematüre patients with preexisting lung disease, should be probed for history of multiple punctures, trauma, or surgery and should have prompt evaluation for AVF. If it can be diagnosed and repaired, most of the cases have been shown to decrease the stress on the heart and reverse the pathologic hemodynamics.

  10. Multisite Tissue Oxygenation Monitoring Indicates Organ-Specific Flow Distribution and Oxygen Delivery Related to Low Cardiac Output in Preterm Infants With Clinical Sepsis

    NARCIS (Netherlands)

    van der Laan, Michelle E.; Roofthooft, Marcus T. R.; Fries, Marian W. A.; Schat, Trijntje E.; Bos, Arend F.; Berger, Rolf M. F.; Kooi, Elisabeth M. W.

    Objectives: Cardiac output may be compromised in preterm infants with sepsis. Whether low cardiac output is associated with low tissue oxygen supply in these patients is unclear. The aim of the current study was to assess the association between cardiac output, assessed by echocardiography, and

  11. Mathematical basis for the measurement of absolute and fractional cardiac output with diffusible tracers by compartmental analysis methods

    International Nuclear Information System (INIS)

    Charkes, N.D.

    1984-01-01

    Using compartmental analysis methods, a mathematical basis is given for the measurement of absolute and fractional cardiac output with diffusible tracers. Cardiac output is shown to be the product of the blood volume and the sum of the rate constants of tracer egress from blood, modified by a factor reflecting transcapillary diffusibility, the transfer fraction. The return of tracer to the blood and distant (intracellular) events are shown to play no role in the solution. Fractional cardiac output is the ratio of the rate constant of tracer egress from blood to an organ, divided by the sum of the egress constants from blood. Predominantly extracellular ions such as sodium or bromide are best suited for this technique, although theoretically any diffusible tracer whose compartmental model can be solved may be used. It is shown that fractional cardiac output is independent of the transfer fraction, and therefore can be measured accurately by tracers which are not freely diffusible

  12. Low Cardiac Output Leads Hepatic Fibrosis in Right Heart Failure Model Rats

    Science.gov (United States)

    Fujimoto, Yoshitaka; Urashima, Takashi; Shimura, Daisuke; Ito, Reiji; Kawachi, Sadataka; Kajimura, Ichige; Akaike, Toru; Kusakari, Yoichiro; Fujiwara, Masako; Ogawa, Kiyoshi; Goda, Nobuhito; Ida, Hiroyuki; Minamisawa, Susumu

    2016-01-01

    Background Hepatic fibrosis progresses with right heart failure, and becomes cardiac cirrhosis in a severe case. Although its causal factor still remains unclear. Here we evaluated the progression of hepatic fibrosis using a pulmonary artery banding (PAB)-induced right heart failure model and investigated whether cardiac output (CO) is responsible for the progression of hepatic fibrosis. Methods and Results Five-week-old Sprague-Dawley rats divided into the PAB and sham-operated control groups. After 4 weeks from operation, we measured CO by echocardiography, and hepatic fibrosis ratio by pathological examination using a color analyzer. In the PAB group, CO was significantly lower by 48% than that in the control group (78.2±27.6 and 150.1±31.2 ml/min, Pright failure heart model rats. PMID:26863419

  13. Non-invasive measurement of cardiac output in heart failure patients using a new foreign gas rebreathing technique

    DEFF Research Database (Denmark)

    Gabrielsen, Anders; Videbaek, Regitze; Schou, Morten

    2002-01-01

    Values of effective pulmonary blood flow (Q(EP)) and cardiac output, determined by a non-invasive foreign gas rebreathing method (CO(RB)) using a new infrared photoacoustic gas analysing system, were compared with measurements of cardiac output obtained by the direct Fick (CO(FICK)) and thermodil......Values of effective pulmonary blood flow (Q(EP)) and cardiac output, determined by a non-invasive foreign gas rebreathing method (CO(RB)) using a new infrared photoacoustic gas analysing system, were compared with measurements of cardiac output obtained by the direct Fick (CO...... with significant shunt flow. In the eight patients without significant shunt flow, the agreement between Q(EP) and CO(FICK) was 0.3 +/- 0.9 litre x min(-1). In conclusion, a foreign gas rebreathing method with a new infrared photoacoustic gas analyser provided at least as reliable a measure of cardiac output...... as did thermodilution. In the absence of significant shunt flow, measurement of Q(EP) itself provides a reliable estimate of cardiac output in heart failure patients. The infrared photoacoustic gas analyser markedly facilitates clinical use of the rebreathing method in general, which makes the method...

  14. Influence of continuous renal replacement therapy on cardiac output measurement using thermodilution techniques.

    Science.gov (United States)

    Heise, D; Faulstich, M; Mörer, O; Bräuer, A; Quintel, M

    2012-03-01

    Acute renal failure (ARF) ranks among the most frequent complications in critically ill patients and continuous renal replacement therapy (CRRT) is a typical treatment regimen in intensive care patients. Contributing factors to ARF, such as septic shock and hemodynamic instability require extended hemodynamic monitoring, and the simultaneous use of CRRT and cardiac output measurement is common. In view of this, a systematic analysis of the interaction between CRRT and cardiac output measurements by thermodilution is warranted. Cardiac output (CO) is commonly measured with thermodilution-based methods in critically ill patients. The methods are accurate but the measurements are affected by inconstant indicator volumes or changes in blood temperature. Because continuous renal replacement therapy (CRRT) may alter blood volume and temperature, we investigated its effect on thermodilution-based CO measurement. Thirty-two intensive care patients with both CRRT and CO monitoring were studied. Hemodynamic parameters were first measured in quintuple with bolus injections of cold saline during CRRT. Further five measurements were performed after CRRT had been shut off, and a final five measurements were performed after it had been restarted. Fifty measurement series were performed in patients with a pulmonary artery catheter and 25 in patients using a transpulmonary thermodilution method (PiCCO®). The first measurements in each series after switching CRRT off or on deviated most markedly from the average. When these measurements were excluded, the averaged CO values with and without CRRT differed significantly but by measurement error was only observed immediately after CRRT was switched off or on. Subsequent CO measurements did not depend on the CRRT status. Interrupting CRRT before measuring CO is not generally recommended, however, if interrupted, it is crucial to wait for blood temperature to reach a steady state before initiating the first measurements.

  15. A preliminary study evaluating cardiac output measurement using Pressure Recording Analytical Method (PRAM) in anaesthetized dogs.

    Science.gov (United States)

    Briganti, Angela; Evangelista, Flavia; Centonze, Paola; Rizzo, Annaliso; Bentivegna, Francesco; Crovace, Antonio; Staffieri, Francesco

    2018-03-06

    Haemodynamic variations normally occur in anaesthetized animals, in relation to the animal status, administered drugs, sympathetic and parasympathetic tone, fluid therapy and surgical stimulus. The possibility to measure some cardiovascular parameters, such as cardiac output (CO), during anaesthesia would be beneficial for both the anaesthesia management and its outcome. New techniques for the monitoring of CO are aimed at finding methods which are non invasive, accurate and with good trending ability, which can be used in a clinical setting. The aim of this study was to compare the Pressure Recording Analytical Method (PRAM) with the pulmonary artery thermodilution (TD) for the measurement of cardiac output in 6 anaesthetized critically ill dogs. Fifty-four pairs of CO measurements were obtained with a median (range) of 3.33 L/min (0.81-7.21) for PRAM-CO and 3.48 L/min (1.41-6.56) for TD-CO. The Bland-Altman analysis showed a mean bias of 0.17 L/min with limits of agreement (LoA) of - 0.46 to 0.81 L/min. The percentage error resulted 18.2%. The 4-quadrant plot analysis showed an acceptable concordance (93%) between the 2 methods. The polar plot showed a good trending ability with the mean angular bias of 3.9° and radial LoA ± 12.1°. The PRAM resulted in good precision, acceptable concordance and good trending ability for the measure of CO in the anaesthetized dog, representing a promising alternative to thermodilution for the measurement of CO. Among all the pulse contour methods available on the market it is the only one that does not require any calibration or adjustment of the measurement. Further studies are required to verify the ability of this method to accurately measure cardiac output even during unstable hemodynamic conditions.

  16. Estimating changes in cardiac output using an implanted hemodynamic monitor in heart failure patients

    DEFF Research Database (Denmark)

    Ståhlberg, Marcus; Damgaard, Morten; Ersgård, David

    2010-01-01

    OBJECTIVES: The aim of this study was to evaluate an algorithm that estimates changes in cardiac output (CO) from right ventricular (RV) pressure waveforms derived from an implantable hemodynamic monitor (IHM) in heart failure patients. DESIGN: Twelve heart failure patients (NYHA II-III, EF 32...... was -0.39 L/min (11%). Limits of agreement were +/-1.56 L/min and relative error was 21%. CONCLUSIONS: A simple algorithm based on RV pressure wave form characteristics derived from an IHM can be used to estimate changes in CO in heart failure patients. These findings encourage further research aiming...

  17. Hereditary Hemorrhagic Telangiectasia Presenting as High Output Cardiac Failure during Pregnancy

    Directory of Open Access Journals (Sweden)

    Tareq Goussous

    2009-01-01

    Full Text Available High-output cardiac failure secondary to hepatic involvement is a rare complication of hereditary hemorrhagic telangiectasia (HHT. Here we report a 43-year-old woman who presented at 29 weeks gestation of her second pregnancy with complications of right-sided heart failure and preterm labor. After delivery via cesarean section, the patient was found to have intrahepatic arteriovenous malformations through non-invasive imaging. Subsequently, a family history of vascular malformations and epistaxis was elucidated and a diagnosis of HHT was made. This case is presented, along with a review of the literature and discussion of hepatic involvement in HHT with particular focus on the pregnant patient.

  18. Depressed left and right ventricular cardiac output in fetuses of diabetic mothers.

    Science.gov (United States)

    Winter, Jennifer; Kulkarni, Aparna; Craft, Mary; Li, Ling; Hornberger, Lisa; Danford, David A; Kutty, Shelby

    2018-01-15

    We compared right and left ventricular cardiac output (RVCO and LVCO) in fetuses of diabetic mothers (FDM) to a large normal cohort. We prospectively enrolled 264 normal fetuses and 30 FDM. Fetal CO parameters: semilunar valve velocity time integrals (AVVTI, PVVTI), ventricular outflow diameters (LVOTD, RVOTD), stroke volumes (AVSV, PVSV) were measured, and LVCO and RVCO calculated.  These were normalized using nonlinear regression to estimated fetal weight (EFW) to provide means and standard deviations. Among FDMs, mean Z-scores and 95% confidence limits (CL) were calculated, and compared to zero. LVCO, RVCO, and parameters they were calculated from, increased predictably and non-linearly with increasing EFW.  In FDM, LVCO was depressed (mean Z -1.679, 95% CL -2.404, -0.955, pFDM have significantly lower right and left heart stroke volumes and outputs for weight than do normal fetuses. © 2018 The authors.

  19. Input-output linearizing tracking control of induction machine with the included magnetic saturation

    DEFF Research Database (Denmark)

    Dolinar, Drago; Ljusev, Petar; Stumberger, Gorazd

    2003-01-01

    The tracking control design of an induction motor, based on input-output linearisation with magnetic saturation included is addressed. The magnetic saturation is represented by a nonlinear magnetising curve for the iron core and is used in the control, the observer of the state variables, and in ...

  20. Comparison of multiple non-invasive methods of measuring cardiac output during pregnancy reveals marked heterogeneity in the magnitude of cardiac output change between women.

    Science.gov (United States)

    Petersen, John W; Liu, Jing; Chi, Yueh-Yun; Lingis, Melissa; Williams, R Stan; Rhoton-Vlasak, Alice; Segal, Mark S; Conrad, Kirk P

    2017-04-01

    Various non-invasive methods are available to measure cardiac output (CO) during pregnancy. We compared serial measures of CO using various methods to determine which provided the least variability. Ten patients with spontaneous pregnancy had estimation of CO at baseline prior to becoming pregnant and at the end of the first and third trimesters. Echocardiographic data were used to estimate CO using the Teichholz method, Simpson's biplane method, and the Doppler determined velocity time integral (VTI) method. In addition, a Bioz Dx device was used to estimate CO by impedance cardiography. CO estimated with the VTI method had the lowest beat-to-beat variability. CO estimated with the VTI method was higher than CO estimated with the 2D-Teichholz method and Simpson's method. The percent change in CO during pregnancy was similar for all echo methods (VTI, Teichholz, and Simpson's biplane). Baseline CO determined with impedance cardiography was higher than CO determined with the VTI method. However, change in CO during pregnancy was significantly lower when measured with impedance cardiography. There was marked heterogeneity in the degree of rise in CO during the first trimester (-3 to 55%). The wide variation in the gestational rise in CO was unexpected, and at least in part secondary to variable increase in heart rate. We recommend the use of the Doppler determined VTI method for the estimation of CO in pregnancy. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  1. The Unpredictable Effect of Changing Cardiac Output on Hypoxemia after Acute Pulmonary Thromboembolism

    Directory of Open Access Journals (Sweden)

    John Y. C. Tsang

    2008-01-01

    Full Text Available Previous studies reported that the degree of hypoxemia following acute pulmonary thromboembolism (APTE was highly variable and that its mechanism was mainly due to the creation of many high and low ventilation/perfusion (V/Q units, as a result of the heterogeneous regional blood flow (Q caused by embolic obstruction. We studied the effect of changing cardiac output (Q t on gas exchange after APTE in 5 embolized piglets (23 ± 3 Kg, using Dobutamine intermittently at approximately 20 μg/kg/min for 120 minutes. The distribution of ventilation (V and perfusion (Q at various times was mapped using fluorescent microspheres in 941 ± 60 lung regions. After APTE, increase in Q t by Dobutamine improved venous oxygen tension (PvO 2 but arterial PaO 2 did not change consistently. On the other hand, cluster analysis showed that the V/Q ratio of most lung regions was lowered due to increases in Q at the same time. We concluded that the effect of changing cardiac output on gas exchange following APTE was affected by the simultaneous and varying balance between the changing V/Q mismatch and the concomitantly changing PvO 2 , which might explain the unpredictability of PaO 2 in the clinical setting.

  2. [Non-invasive determination of cardiac output by continuous wave Doppler in air rescue service].

    Science.gov (United States)

    Knobloch, K; Hubrich, V; Rohmann, P; Lüpkemann, M; Phillips, R; Gerich, T; Krettek, C

    2005-12-01

    Determination of cardiac output (CO) enables to assess the hemodynamic situation as well as to administer optimal catecholamine therapy especially in critically compromised patients with hemodynamic instability. Invasive determination of CO is possible via a Swan-Ganz-catheter with its associated risk of implantation in the hospital. Using the Doppler technique, we evaluated the feasibility of the USCOM-system for non-invasive CO determination in preclinical emergency medicine in air rescue service. In 32 patients (17 months to 92-years-old) cardiac output was determined non-invasively (USCOM) at the scene and during the helicopter transport at Christoph 4, based at Hannover Medical School. Simultaneously, blood pressure, ECG and oxygen saturation were determined. Non-invasive CO was assessed by a suprasternal access aiming at the aorta ascendens. 19 patients were unconscious due to cardial and non-cardial reasons, and 13 were conscious (sepsis, status epilepticus, anaphylactic reaction). 7 patients were hemodynamically unstable. In three patients the monitor was used during interhospital transfer by helicopter. Non-invasively determined CO via the USCOM system was 4.8 +/- 0.7 l/min with a cardiac index of 2.4 +/- 0.3 l/m (2). Highest CO values were determined in a patient with sepsis and during a grand-mal-status in epilepsy (CO 8.2 l/min). All examinations were done by the same emergency physician of the emergency helicopter Christoph 4 immediately after arrival at the scene. The examination took on average 25 seconds. During the helicopter transport, several consecutive CO measurements were performed to assess volume and catecholamine therapy with increase of stroke volume after volume load with colloidal fluids. Using the USCOM system it is possible to determine the beat-to-beat cardiac output in air rescue service non-invasively. The emergency physician gains additional crucial hemodynamic information to diagnose and treat adequately by administration of

  3. Reduced peripheral arterial blood flow with preserved cardiac output during submaximal bicycle exercise in elderly heart failure

    Directory of Open Access Journals (Sweden)

    Leng Xiaoyan

    2009-11-01

    Full Text Available Abstract Background Older heart failure (HF patients exhibit exercise intolerance during activities of daily living. We hypothesized that reduced lower extremity blood flow (LBF due to reduced forward cardiac output would contribute to submaximal exercise intolerance in older HF patients. Methods and Results Twelve HF patients both with preserved and reduced left ventricular ejection fraction (LVEF (aged 68 ± 10 years without large (aorta or medium sized (iliac or femoral artery vessel atherosclerosis, and 13 age and gender matched healthy volunteers underwent a sophisticated battery of assessments including a peak exercise oxygen consumption (peak VO2, b physical function, c cardiovascular magnetic resonance (CMR submaximal exercise measures of aortic and femoral arterial blood flow, and d determination of thigh muscle area. Peak VO2 was reduced in HF subjects (14 ± 3 ml/kg/min compared to healthy elderly subjects (20 ± 6 ml/kg/min (p = 0.01. Four-meter walk speed was 1.35 ± 0.24 m/sec in healthy elderly verses 0.98 ± 0.15 m/sec in HF subjects (p p ≤ 0.03. Conclusion During CMR submaximal bike exercise in the elderly with heart failure, mechanisms other than low cardiac output are responsible for reduced lower extremity blood flow.

  4. Pulse dye densitometry using indigo carmine is useful for cardiac output measurement, but not for circulating blood volume measurement.

    Science.gov (United States)

    Fujita, Y; Yamamoto, T; Fuse, M; Kobayashi, N; Takeda, S; Aoyagi, T

    2004-08-01

    We evaluated the validity of a newly developed pulse dye densitometer for indigo carmine for measuring cardiac output and circulating blood volume. Measurements of cardiac output and circulating blood volume were performed with the indigo carmine densitometer during normovolaemia, hypovolaemia and hypervolaemia in nine mongrel dogs under general anaesthesia. The validity was evaluated by comparison of the values of cardiac output and circulating blood volume obtained by the thermodilution technique and the 51Cr-labelled red blood cell method, respectively. We also examined indigo carmine removal by continuous veno-venous haemofiltration after indigo carmine injection. There was good agreement between dye densitometer- and thermodilution-derived cardiac output (r = 0.885, P dye-densitometer-derived circulating blood volume was greater than that of the 51Cr-labelled red blood cell method, and both values showed weak agreement (r = 0.587, P indigo carmine through continuous veno-venous haemofiltration was 0.34+/-0.06. These data indicate that indigo carmine densitometry is a reliable method for cardiac output determination, but it overestimates circulating blood volume, probably due to the transition of indigo carmine into the extravascular space in the systemic circulation.

  5. Endurance Training and V˙O2max: Role of Maximal Cardiac Output and Oxygen Extraction.

    Science.gov (United States)

    Montero, David; Diaz-Cañestro, Candela; Lundby, Carsten

    2015-10-01

    Although endurance training (ET) commonly augments maximal oxygen consumption (V˙O2max), it remains unclear whether such increase is associated with that of maximal cardiac output (Qmax) alone or along with arteriovenous oxygen difference (a-V˙O2diff). Herein, we sought to systematically review and determine the effects of ET on V˙O2max, Qmax, and a-V˙O2diff at maximal exercise, and on their associations, in healthy young subjects. We conducted a systematic search of MEDLINE, Scopus, and Web of Science (from their inception until September 2014) for articles assessing the effects of ET lasting ≥3 wk on V˙O2max and Qmax and/or a-V˙O2diff at maximal exercise in healthy young adults (mean age V˙O2max, Qmax, and a-V˙O2diff at maximal exercise between posttraining and pretraining measurements. Subgroup and meta-regression analyses were used to evaluate associations among SMD and potential moderating factors. Thirteen studies were included after systematic review, comprising a total of 130 untrained or moderately trained healthy young subjects (mean age, 22-28 yr). Duration of ET programs ranged from 5 to 12.9 wk. After data pooling, V˙O2max (SMD = 0.75, P P V˙O2diff at maximal exercise (SMD = 0.21, P = 0.23), were increased after ET. No significant heterogeneity was detected. With meta-regression, the SMD in Qmax was positively associated with the SMD in V˙O2max (B = 0.91, P = 0.007). The SMD in a-V˙O2diff at maximal exercise was not associated with the SMD in V˙O2max (B = 0.20, P = 0.40). Based on a relatively small number of studies, improvement in V˙O2max following 5-13 wk of ET is associated with increase in Qmax, but not in a-V˙O2diff, in previously untrained to moderately trained healthy young individuals.

  6. Effects of ventilation on cardiac output determined by inert gas rebreathing

    DEFF Research Database (Denmark)

    Damgaard, Morten; Norsk, Peter

    2005-01-01

    . Therefore, in 10 healthy males we investigated the effects of changes in ventilation pattern on cardiac output (CO) estimated by an N(2)O-rebreathing technique. Reducing the rebreathing volume (V(reb)) from 1.5 to 1.0 l diminished CO by 0.5 +/- 0.2 l min(-1), whereas an increase in V(reb) from 1.5 to 2.5 l...... breaths min(-1) or adding serial dead space by up to 600 ml did not affect the determination of CO. In conclusion, the rebreathing procedure for determination of CO at rest should be performed following a normal tidal expiration with a rebreathing bag volume of between 1.5 and 2.5 l and with manoeuvres...... separated by at least 3-5 min. Variations in RF within the physiological range from 15 to 30 breaths min(-1) do not affect outcome of the measurements....

  7. Phlebotomy eliminates the maximal cardiac output response to six weeks of exercise training

    DEFF Research Database (Denmark)

    Bonne, Thomas Christian; Doucende, Gregory; Flück, Daniela

    2014-01-01

    With this study we tested the hypothesis that six weeks of endurance training increases maximal cardiac output (Qmax) relatively more by elevating blood volume (BV) than by inducing structural and functional changes within the heart. Nine healthy but untrained volunteers (VO2max 47 ± 5 ml.min(-1......).kg(-1)) underwent supervised training (60 min; 4 times weekly at 65% VO2max for six weeks) and Qmax was determined by inert gas re-breathing during cycle ergometer exercise before and after the training period. After the training period, blood volume (determined in duplicates by CO re......-breathing) was re-established to pre-training values by phlebotomy and Qmax was quantified again. Resting echography revealed no structural heart adaptations as a consequence of the training intervention. Following the training period, plasma volume (PV), red blood cell volume (RBCV) and BV increased (p...

  8. Reference values for total blood volume and cardiac output in humans

    Energy Technology Data Exchange (ETDEWEB)

    Williams, L.R. [Indiana Univ., South Bend, IN (United States). Division of Liberal Arts and Sciences

    1994-09-01

    Much research has been devoted to measurement of total blood volume (TBV) and cardiac output (CO) in humans but not enough effort has been devoted to collection and reduction of results for the purpose of deriving typical or {open_quotes}reference{close_quotes} values. Identification of normal values for TBV and CO is needed not only for clinical evaluations but also for the development of biokinetic models for ultra-short-lived radionuclides used in nuclear medicine (Leggett and Williams 1989). The purpose of this report is to offer reference values for TBV and CO, along with estimates of the associated uncertainties that arise from intra- and inter-subject variation, errors in measurement techniques, and other sources. Reference values are derived for basal supine CO and TBV in reference adult humans, and differences associated with age, sex, body size, body position, exercise, and other circumstances are discussed.

  9. Left ventricular atrioventricular plane displacement is preserved with lifelong endurance training and is the main determinant of maximal cardiac output

    DEFF Research Database (Denmark)

    Steding-Ehrenborg, Katarina; Boushel, Robert C; Calbet, José A

    2015-01-01

    subjects (29 ± 4 years) underwent cardiac MR. All subjects underwent maximal exercise testing and for elderly subjects maximal cardiac output during cycling was determined using dye dilution technique. RESULTS: Longitudinal and radial contribution to stroke volume did not differ between groups......BACKGROUND: Age-related decline in cardiac function can be prevented or postponed by lifelong endurance training. However, effects of normal ageing as well as of lifelong endurance exercise on longitudinal and radial contribution to stroke volume are unknown. The aim of this study was to determine...... groups for RVAVPD (P = 0.2). LVAVPD was an independent predictor of maximal cardiac output (R(2 = ) 0.61, P groups. However, how longitudinal pumping...

  10. Effect of heat stress on cardiac output and systemic vascular conductance during simulated hemorrhage to presyncope in young men

    DEFF Research Database (Denmark)

    Ganio, Matthew S; Overgaard, Morten; Seifert, Thomas

    2012-01-01

    During moderate actual or simulated hemorrhage, as cardiac output decreases, reductions in systemic vascular conductance (SVC) maintain mean arterial pressure (MAP). Heat stress, however, compromises the control of MAP during simulated hemorrhage, and it remains unknown whether this response is due...... to a persistently high SVC and/or a low cardiac output. This study tested the hypothesis that an inadequate decrease in SVC is the primary contributing mechanism by which heat stress compromises blood pressure control during simulated hemorrhage. Simulated hemorrhage was imposed via lower body negative pressure...... (LBNP) to presyncope in 11 passively heat-stressed subjects (increase core temperature: 1.2 ± 0.2°C; means ± SD). Cardiac output was measured via thermodilution, and SVC was calculated while subjects were normothermic, heat stressed, and throughout subsequent LBNP. MAP was not changed by heat stress...

  11. Transit time dispersion in pulmonary and systemic circulation: effects of cardiac output and solute diffusivity.

    Science.gov (United States)

    Weiss, Michael; Krejcie, Tom C; Avram, Michael J

    2006-08-01

    We present an in vivo method for analyzing the distribution kinetics of physiological markers into their respective distribution volumes utilizing information provided by the relative dispersion of transit times. Arterial concentration-time curves of markers of the vascular space [indocyanine green (ICG)], extracellular fluid (inulin), and total body water (antipyrine) measured in awake dogs under control conditions and during phenylephrine or isoproterenol infusion were analyzed by a recirculatory model to estimate the relative dispersions of transit times across the systemic and pulmonary circulation. The transit time dispersion in the systemic circulation was used to calculate the whole body distribution clearance, and an interpretation is given in terms of a lumped organ model of blood-tissue exchange. As predicted by theory, this relative dispersion increased linearly with cardiac output, with a slope that was inversely related to solute diffusivity. The relative dispersion of the flow-limited indicator antipyrine exceeded that of ICG (as a measure of intravascular mixing) only slightly and was consistent with a diffusional equilibration time in the extravascular space of approximately 10 min, except during phenylephrine infusion, which led to an anomalously high relative dispersion. A change in cardiac output did not alter the heterogeneity of capillary transit times of ICG. The results support the view that the relative dispersions of transit times in the systemic and pulmonary circulation estimated from solute disposition data in vivo are useful measures of whole body distribution kinetics of indicators and endogenous substances. This is the first model that explains the effect of flow and capillary permeability on whole body distribution of solutes without assuming well-mixed compartments.

  12. Continuous versus bolus thermodilution cardiac output measurements--a comparative study.

    Science.gov (United States)

    Mihaljevic, T; von Segesser, L K; Tönz, M; Leskosek, B; Seifert, B; Jenni, R; Turina, M

    1995-05-01

    To compare the methods for continuous and bolus thermodilution cardiac output measurements. In vivo and in vitro experimental studies. Surgical research division in a university hospital. Eight calves and flow bench model. Data were collected in vivo from eight calves instrumented with pulmonary artery catheters, which allowed both continuous and bolus thermodilution measurements. The pulmonary artery catheter was placed through the external jugular vein. All in vitro measurements were performed using a flow bench model. A total of 232 bolus and continuous thermodilution measurements were analysed in vivo to determine the degree of agreement between the two methods. The absolute measurement bias was 0.14 L/min with 95% confidence limits ranging from -0.83 to 1.15 L/min. In vitro analysis of 576 measurements at six different temperature points (range 31 degrees to 41 degrees C), using clinically relevant flows (2 to 9 L/min), showed overestimation of flow values using continuous and bolus thermodilution methods. However, the continuous method showed better accuracy by a lower degree of overestimation. Systematic error was 9.7 +/- 8.4 (SD) % for continuous and 11.1 +/- 6.3% for the bolus method (p thermal filament of the pulmonary catheter impaired the accuracy of continuous measurement without affecting results from bolus measurements (systematic error -26.8 +/- 8.2% for continuous and -5.2 +/- 4.1% for bolus thermodilution). Continuous thermodilution cardiac output measurement provided higher accuracy and greater resistance to thermal noise than standard bolus measurements. The correct placement of the catheter is essential for precise measurements.

  13. Risk factors for low cardiac output syndrome after coronary artery bypass grafting surgery.

    Science.gov (United States)

    Sá, Michel Pompeu Barros de Oliveira; Nogueira, Joana Rosa Costa; Ferraz, Paulo Ernando; Figueiredo, Omar Jacobina; Cavalcante, Wagner Cid Palmeira; Cavalcante, Thiago Cid Palmeira; Silva, Hugo Thiago Torres da; Santos, Cecília Andrade; Lima, Renato Oliveira de Albuquerque; Vasconcelos, Frederico Pires; Lima, Ricardo de Carvalho

    2012-01-01

    Low cardiac output syndrome (LCOS) is a serious complication after cardiac surgery and is associated with significant morbidity and mortality. The aim of this study is to identify risk factors for LCOS in patients undergoing coronary artery bypass grafting (CABG) in the Division of Cardiovascular Surgery of Pronto Socorro Cardiológico de Pernambuco - PROCAPE (Recife, PE, Brazil). A historical prospective study comprising 605 consecutive patients operated between May 2007 and December 2010. We evaluated 12 preoperative and 7 intraoperative variables. We applied univariate and multivariate logistic regression analysis. The incidence of LCOS was 14.7% (n = 89), with a lethality rate of 52.8% (n = 47). In multivariate analysis by logistic regression, four variables remained as independent risk factors: age > 60 years (OR 2.00, 95% CI 1.20 to 6.14, P = 0.009), on-pump CABG (OR 2.16, 95% CI 1.40 to 7.08, P = 0.006), emergency surgery (OR 4.71, 95% CI 1.34 to 26.55, P = 0.028), incomplete revascularization (OR 2.62, 95% CI 1.32 to 5.86, P = 0.003), and ejection fraction 60 years of off-pump CABG, emergency surgery, incomplete CABG and ejection fraction <50%.

  14. A System for Continuous Estimating and Monitoring Cardiac Output via Arterial Waveform Analysis.

    Science.gov (United States)

    Vakily, A; Parsaei, H; Movahhedi, M M; Sahmeddini, M A

    2017-06-01

    Cardiac output (CO) is the total volume of blood pumped by the heart per minute and is a function of heart rate and stroke volume. CO is one of the most important parameters for monitoring cardiac function, estimating global oxygen delivery and understanding the causes of high blood pressure. Hence, measuring CO has always been a matter of interest to researchers and clinicians. Several methods have been developed for this purpose, but a majority of them are either invasive, too expensive or need special expertise and experience. Besides, they are not usually risk free and have consequences. Here, a semi-invasive system was designed and developed for continuous CO measurement via analyzing and processing arterial pulse waves. Quantitative evaluation of developed CO estimation system was performed using 7 signals. It showed that it has an acceptable average error of (6.5%) in estimating CO. In addition, this system has the ability to consistently estimate this parameter and to provide a CO versus time curve that assists in tracking changes of CO. Moreover, the system provides such curve for systolic blood pressure, diastolic blood pressure, average blood pressure, heart rate and stroke volume. Evaluation of the results showed that the developed system is capable of accurately estimating CO. The curves which the system provides for important parameters may be valuable in monitoring hemodynamic status of high-risk surgical patients and critically ill patients in Intensive Care Units (ICU). Therefore, it could be a suitable system for monitoring hemodynamic status of critically ill patients.

  15. High-Intensity Interval Training Increases Cardiac Output and V˙O2max.

    Science.gov (United States)

    Astorino, Todd A; Edmunds, Ross M; Clark, Amy; King, Leesa; Gallant, Rachael A; Namm, Samantha; Fischer, Anthony; Wood, Kimi M

    2017-02-01

    Increases in maximal oxygen uptake (V˙O2max) frequently occur with high-intensity interval training (HIIT), yet the specific adaptation explaining this result remains elusive. This study examined changes in V˙O2max and cardiac output (CO) in response to periodized HIIT. Thirty-nine active men and women (mean age and V˙O2max = 22.9 ± 5.4 yr and 39.6 ± 5.6 mL·kg·min) performed HIIT and 32 men and women (age and V˙O2max = 25.7 ± 4.5 yr and 40.7 ± 5.2 mL·kg·min) were nonexercising controls (CON). The first 10 sessions of HIIT required eight to ten 60 s bouts of cycling at 90%-110% percent peak power output interspersed with 75 s recovery, followed by randomization to one of three regimes (sprint interval training (SIT), high-volume interval training (HIITHI), or periodized interval training (PER) for the subsequent 10 sessions. Before, midway, and at the end of training, progressive cycling to exhaustion was completed during which V˙O2max and maximal CO were estimated. Compared with CON, significant (P training groups. Increases in V˙O2max exhibited in response to different HIIT regimes are due to improvements in oxygen delivery.

  16. Depressed left and right ventricular cardiac output in fetuses of diabetic mothers

    Directory of Open Access Journals (Sweden)

    Jennifer Winter MD

    2018-01-01

    Full Text Available Introduction: We compared right and left ventricular cardiac output (RVCO and LVCO in fetuses of diabetic mothers (FDM with a large normal cohort. Methods: We prospectively enrolled 264 normal fetuses and 30 FDM. Fetal CO parameters such as semilunar valve velocity time integrals (AVVTI, PVVTI, ventricular outflow diameters (LVOTD, RVOTD and stroke volumes (AVSV, PVSV were measured, and LVCO and RVCO were calculated. These were normalized using non-linear regression to estimated fetal weight (EFW to provide means and standard deviations. Among FDMs, mean Z scores and 95% confidence limits (CL were calculated and compared to zero. Results: LVCO, RVCO and parameters they were calculated from, increased predictably and non-linearly with increasing EFW. In FDM, LVCO was depressed (mean Z −1.679, 95% CL −2.404, −0.955, P < 0.001, and AVVTI, LVOTD and AVSV were significantly lower than normal. Similarly, RVCO (mean Z = −1.119, CL −1.839, −0.400, P = 0.003, RVOTD (mean −2.085, CL −3.077, −1.093, P < 0.001 and PVSV (mean −1.184, CL −1.921, −0.446, P = 0.003 were lower than normal, however, PVVTI was not different (mean Z 0.078, CL −0.552, +0.707, P = 0.803. Conclusion: Normal biventricular stroke volumes and outputs follow a non-linear regression with EFW. FDM have significantly lower right and left heart stroke volumes and outputs for weight than do normal fetuses.

  17. Impact of pacing modality and biventricular pacing on cardiac output and coronary conduit flow in the post-cardiotomy patient.

    LENUS (Irish Health Repository)

    Healy, David G

    2012-02-03

    We have previously demonstrated the role of univentricular pacing modalities in influencing coronary conduit flow in the immediate post-operative period in the cardiac surgery patient. We wanted to determine the mechanism of this improved coronary conduit and, in addition, to explore the possible benefits with biventricular pacing. Sixteen patients undergoing first time elective coronary artery bypass grafting who required pacing following surgery were recruited. Comparison of cardiac output and coronary conduit flow was performed between VVI and DDD pacing with a single right ventricular lead and biventricular pacing lead placement. Cardiac output was measured using arterial pulse waveform analysis while conduit flow was measured using ultrasonic transit time methodology. Cardiac output was greatest with DDD pacing using right ventricular lead placement only [DDD-univentricular 5.42 l (0.7), DDD-biventricular 5.33 l (0.8), VVI-univentricular 4.71 l (0.8), VVI-biventricular 4.68 l (0.6)]. DDD-univentricular pacing was significantly better than VVI-univentricular (P=0.023) and VVI-biventricular pacing (P=0.001) but there was no significant advantage to DDD-biventricular pacing (P=0.45). In relation to coronary conduit flow, DDD pacing again had the highest flow [DDD-univentricular 55 ml\\/min (24), DDD-biventricular 52 ml\\/min (25), VVI-univentricular 47 ml\\/min (23), VVI-biventricular 50 ml\\/min (26)]. DDD-univentricular pacing was significantly better than VVI-univentricular (P=0.006) pacing but not significantly different to VVI-biventricular pacing (P=0.109) or DDD-biventricular pacing (P=0.171). Pacing with a DDD modality offers the optimal coronary conduit flow by maximising cardiac output. Biventricular lead placement offered no significant benefit to coronary conduit flow or cardiac output.

  18. Noninvasive cardiac output determination using applanation tonometry-derived radial artery pulse contour analysis in critically ill patients

    DEFF Research Database (Denmark)

    Compton, Friederike; Wittrock, Marc; Schaefer, Juergen-Heiner

    2008-01-01

    Conventional thermodilution cardiac output (CO) monitoring is limited mainly to intensive care units and operating rooms because it requires the use of invasive techniques. To reduce the potential for complications and to broaden the applicability of hemodynamic monitoring, noninvasive methods fo...

  19. Effects of levosimendan for low cardiac output syndrome in critically ill patients

    DEFF Research Database (Denmark)

    Koster, Geert; Wetterslev, Jørn; Gluud, Christian

    2015-01-01

    in the systematic review and 49 trials (6,688 patients) in the meta-analysis. One trial had low risk of bias and nine trials (2,490 patients) were considered lower risk of bias. Trials compared levosimendan with placebo, control interventions, and other inotropes. Pooling all trials including heterogenous...... populations was considered inappropriate. Pooled analysis of 30 trials including critically ill patients not having cardiac surgery showed an association between levosimendan and mortality (RR 0.83, TSA-adjusted 95 % CI 0.59-0.97), while trials with lower risk of bias showed no significant difference (RR 0...

  20. Transthoracic echocardiography: an accurate and precise method for estimating cardiac output in the critically ill patient.

    Science.gov (United States)

    Mercado, Pablo; Maizel, Julien; Beyls, Christophe; Titeca-Beauport, Dimitri; Joris, Magalie; Kontar, Loay; Riviere, Antoine; Bonef, Olivier; Soupison, Thierry; Tribouilloy, Christophe; de Cagny, Bertrand; Slama, Michel

    2017-06-09

    Cardiac output (CO) monitoring is a valuable tool for the diagnosis and management of critically ill patients. In the critical care setting, few studies have evaluated the level of agreement between CO estimated by transthoracic echocardiography (CO-TTE) and that measured by the reference method, pulmonary artery catheter (CO-PAC). The objective of the present study was to evaluate the precision and accuracy of CO-TTE relative to CO-PAC and the ability of transthoracic echocardiography to track variations in CO, in critically ill mechanically ventilated patients. Thirty-eight mechanically ventilated patients fitted with a PAC were included in a prospective observational study performed in a 16-bed university hospital ICU. CO-PAC was measured via intermittent thermodilution. Simultaneously, a second investigator used standard-view TTE to estimate CO-TTE as the product of stroke volume and the heart rate obtained during the measurement of the subaortic velocity time integral. Sixty-four pairs of CO-PAC and CO-TTE measurements were compared. The two measurements were significantly correlated (r = 0.95; p < 0.0001). The median bias was 0.2 L/min, the limits of agreement (LOAs) were -1.3 and 1.8 L/min, and the percentage error was 25%. The precision was 8% for CO-PAC and 9% for CO-TTE. Twenty-six pairs of ΔCO measurements were compared. There was a significant correlation between ΔCO-PAC and ΔCO-TTE (r = 0.92; p < 0.0001). The median bias was -0.1 L/min and the LOAs were -1.3 and +1.2 L/min. With a 15% exclusion zone, the four-quadrant plot had a concordance rate of 94%. With a 0.5 L/min exclusion zone, the polar plot had a mean polar angle of 1.0° and a percentage error LOAs of -26.8 to 28.8°. The concordance rate was 100% between 30 and -30°. When using CO-TTE to detect an increase in ΔCO-PAC of more than 10%, the area under the receiving operating characteristic curve (95% CI) was 0.82 (0.62-0.94) (p < 0.001). A ΔCO-TTE of more than 8

  1. Evaluation of concordance among three cardiac output measurement techniques in adult patients during cardiovascular surgery postoperative care.

    Science.gov (United States)

    Muñoz, L; Velandia, A; Reyes, L E; Arevalo-Rodríguez, I; Mejía, C; Asprilla, D; Uribe, D V; Arevalo, J J

    2017-12-01

    The standard method for cardiac output measuring is thermodilution although it is an invasive technique. Transesophageal Echocardiography (TEE) offers a dynamic and functional alternative to thermodilution. Analyze concordance between two TEE methods and thermodilution for cardiac output assessment. Observational concordance study in cardiovascular surgery patients that required pulmonary artery catheter. TEE cardiac output measurement at both mitral annulus (MA) and left ventricle outflow tract (LVOT) were performed. Results were compared with thermodilution. Correlation was evaluated by Lin's concordance correlation coefficient and Bland-Altman analysis. Statistical analysis was undertaken in STATA 13.0. Twenty-five patients were enrolled. Fifty two percent of patients were male, median age and ejection fraction was 63 years and 35% respectively. Median thermodilution, LVOT and MA -measured cardiac output was 3.25 L/min, 3.46 L/min and 8.4 L/min respectively. Different values between thermodilution and MA measurements were found (Lin concordance=0.071; Confidence Interval 95%=-0.009 to 0.151; Spearman's correlation=0.22) as values between thermodilution and LVOT (Lin concordance=0.232; Confidence Interval 95%=-0.12 a 0.537; Spearman's correlation 0.28). Bland-Altman analysis showed greater difference between MA measurements and thermodilution (DM=-0.408; Bland-Altman Limits=-0.809 to -0.007), than the other echocardiographic findings (DM=0.007; Bland-Altman Limits=-0.441 to 0.428). Results from cardiac output measurement by doppler and 2D-TEE on both MA and LVOT do not correlate with those obtained by thermodilution. Copyright © 2017 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

  2. [A dye densitometry analysis method for noninvasive measurement of cardiac output based on NIRS].

    Science.gov (United States)

    Lu, Meng-Meng; Wang, Hong-Xuan; Liu, Guang-Da; Xin, Gui-Jie; Yu, Yong; Zha, Yu-Tong

    2013-12-01

    Currently, there exist technology problems in cardiac output (CO) parameter detection clinically, such as invasive and complex operation, as well as possibility of infection and death for patients. In order to solve these problems, a noninvasive and continuous method based on NIRS for CO detection was presented. In this way, the concentration changing of indocyanine green (ICG) dye in the patient's arterial blood was dynamically measured and analyzed, so that the CO could be noninvasively and continuously measured according to the characteristic parameters of dye densitometry curve. While the ICG dye was injected into the patient's body by the median cubital vein, block of photoelectric pulse dye densitometry measurement system as the lower machine acquired pulse wave data and uploaded the data to upper computer. In the scheme, two specialized light sources of LED at 940 and 805 nm were used to capture the signals of sufferer's fingertip pulse wave synchronously and successively. The CO value could then be successfully calculated through drawing complete ICG concentration variation of dye dilution and excretion process and computing mean transmission time (MTT) by upper computer. Compared with the "gold standard" method of thermodilution, the maximum relative error of this method was below 9. 76%, and the mean relative error was below 4. 39%. The result indicates that the method can be used as a kind of convenient operation, noninvasive and continuous solution for clinical CO measurement.

  3. Distribution of cardiac output in dogs during intravenous infusion of betahistine.

    Science.gov (United States)

    Smith, K A; Meyer, M W

    1976-01-01

    Cardiac output (CO), arterial blood pressure (ABP), heart rate (HR), blood gases and blood flow (BF) to the brain, heart, kidney and skeletal muscles and other cephalic tissues in five dogs were studied before and at 30 minutes of betahistine infusion (0.12 to 0.2 mg per minute per kilogram). The particle distribution method using radioactive labeled 141Ce (15 mu) and 85Sr (15 mu) microspheres was utilized to quantitate and assess BF and CO. In the five dogs, the increase in CO averaged 20.8%, ABP remained constant, and HR increased in all but one exception where it decreased slightly concomitant with a decrease in Paco2. Brain BF increased (+ 29.6%) in the dogs whose Paco2 reamined constant. The BF increased to the heart (25.4%) and skeletal muslce (80%), while BF to the kidney and other tissues did not change. The change in HR appears to account for the change in CO. The dilating effect of betahistine on blood vessels, in the skeletal muscle, brain and heart could reduce peripheral resistance and decreace ABP. Thus, the increase in HR may be mediated through baroreceptor mechanisms rather than by a direct effect of betahistine. In addition, a decrease in Paco2, is more effective for decreasing cerebral BF than betahistine is for increasing blood flow.

  4. A computational model-based validation of Guyton's analysis of cardiac output and venous return curves

    Science.gov (United States)

    Mukkamala, R.; Cohen, R. J.; Mark, R. G.

    2002-01-01

    Guyton developed a popular approach for understanding the factors responsible for cardiac output (CO) regulation in which 1) the heart-lung unit and systemic circulation are independently characterized via CO and venous return (VR) curves, and 2) average CO and right atrial pressure (RAP) of the intact circulation are predicted by graphically intersecting the curves. However, this approach is virtually impossible to verify experimentally. We theoretically evaluated the approach with respect to a nonlinear, computational model of the pulsatile heart and circulation. We developed two sets of open circulation models to generate CO and VR curves, differing by the manner in which average RAP was varied. One set applied constant RAPs, while the other set applied pulsatile RAPs. Accurate prediction of intact, average CO and RAP was achieved only by intersecting the CO and VR curves generated with pulsatile RAPs because of the pulsatility and nonlinearity (e.g., systemic venous collapse) of the intact model. The CO and VR curves generated with pulsatile RAPs were also practically independent. This theoretical study therefore supports the validity of Guyton's graphical analysis.

  5. Cardiac Output Measurements in Septic Patients: Comparing the Accuracy of USCOM to PiCCO

    Directory of Open Access Journals (Sweden)

    Sophia Horster

    2012-01-01

    Full Text Available USCOM is an ultrasound-based method which has been accepted for noninvasive hemodynamic monitoring in various clinical conditions (USCOM, Ultrasonic cardiac output monitoring. The present study aimed at comparing the accuracy of the USCOM device with that of the thermodilution technique in patients with septicemia. We conducted a prospective observational study in a medical but noncardiological ICU of a university hospital. Septic adult patients (median age 55 years, median SAPS-II-Score 43 points on mechanical ventilation and catecholamine support were monitored with USCOM and PiCCO (=70. Seventy paired left-sided CO measurements (transaortic access = COUS-A were obtained. The mean COUS-A were 6.55 l/min (±2.19 versus COPiCCO 6.5 l/min (±2.18. The correlation coefficient was =0.89. Comparison by Bland-Altman analysis revealed a bias of −0.36 l/min (±0.99 l/min leading to a mean percentage error of 29%. USCOM is a feasible and rapid method to evaluate CO in septic patients. USCOM does reliably represent CO values as compared to the reference technique based on thermodilution (PiCCO. It seems to be appropriate in situations where CO measurements are most pertinent to patient management.

  6. Cardiac output is not a significant source of low frequency mean arterial pressure variability

    International Nuclear Information System (INIS)

    Aletti, F; Baselli, G; Hammond, R L; Sala-Mercado, J A; O'Leary, D S; Chen, X; Mukkamala, R

    2013-01-01

    Spontaneous mean arterial pressure (MAP) variability may be mainly due to fluctuations in cardiac output (CO) and total peripheral resistance (TPR). While high frequency (HF ∼ 0.25 Hz) oscillations in MAP are ultimately driven by respiration, the source of low frequency (LF ∼ 0.1 Hz) fluctuations has not been fully elucidated. It is known that CO buffers these oscillations, but there is no evidence on its potential role in also generating them. The main goal was to determine whether CO is a source of LF variability in MAP. Six dogs were chronically instrumented to obtain beat-to-beat measurements of CO and MAP while the dogs were fully awake and at rest. A causal dynamic model was identified to relate the fluctuations in CO to MAP. The model was then used to predict the MAP fluctuations from the CO fluctuations. The CO fluctuations were able to predict about 70% of the MAP oscillations in the HF band but showed no predictive value in the LF band. Hence, respiration induces CO fluctuations in the HF band that, in turn, cause MAP oscillations, while TPR fluctuations appear to be the dominant mediator of LF fluctuations of MAP. CO is not a significant source of these oscillations, and it may only be responsible for dampening them, likely through the baroreflex. (paper)

  7. Agreement between ccNexfin CO-trek cardiac output and intermittent cold-bolus pulmonary thermodilution in a prospective multi-centre study

    NARCIS (Netherlands)

    Sperna Weiland, Nicolaas H.; de Wever, Jim W.; van Duivenvoorde, Yoni; Boer, Christa; Mitrev, Ludmil; Muntazar, Muhammad; Patel, Kinjal; Hollmann, Markus W.; Preckel, Benedikt

    2017-01-01

    The ccNexfin system uses the CO-trek algorithm to analyse a non-invasively obtained arterial pressure waveform and calculate cardiac output (NEXCO). It remains matter of debate whether NEXCO can replace invasive, pulmonary artery catheter derived, cold-bolus pulmonary thermodilution cardiac output

  8. Cardiac output response to changes of the atrioventricular delay in different body positions and during exercise in patients receiving cardiac resynchronization therapy

    DEFF Research Database (Denmark)

    Ståhlberg, Marcus; Damgaard, Morten; Norsk, Peter

    2009-01-01

    AIMS: The aim of this study was to study the haemodynamic effect of atrioventricular delay (AVD) modifications within a narrow range in different body positions and during exercise in patients receiving cardiac resynchronization therapy (CRT). METHODS: The previously optimized AVD was shortened...... and prolonged by 40 ms in 27 CRT patients and 9 controls without heart failure. Cardiac output (CO) was measured by inert gas rebreathing (Innocor) as the average over different body positions (left-lateral, supine, sitting, standing, and exercise). In eight CRT patients with an implantable haemodynamic monitor.......61, Pnarrow range is larger in CRT patients than in normal...

  9. Prevalence of nursing diagnosis of decreased cardiac output and the predictive value of defining characteristics in patients under evaluation for heart transplant

    OpenAIRE

    Matos, Lígia Neres; Guimarães, Tereza Cristina Felippe; Brandão, Marcos Antônio Gomes; Santoro, Deyse Conceição

    2012-01-01

    The purposes of the study were to identify the prevalence of defining characteristics (DC) of decreased cardiac output (DCO) in patients with cardiac insufficiency under evaluation for heart transplantation, and to ascertain the likelihood of defining characteristics being predictive factors for the existence of reduction in cardiac output. Data was obtained by retrospective documental analysis of the clinical records of right-sided heart catheterizations in 38 patients between 2004 and 2009....

  10. Children with Burn Injury Have Impaired Cardiac Output during Submaximal Exercise.

    Science.gov (United States)

    Rivas, Eric; Herndon, David N; Beck, Kenneth C; Suman, Oscar E

    2017-10-01

    Burn trauma damages resting cardiac function; however, it is currently unknown if the cardiovascular response to exercise is likewise impaired. We tested the hypothesis that, in children, burn injury lowers cardiac output (Q˙) and stroke volume (SV) during submaximal exercise. Five children with 49% ± 4% total body surface area (BSA) burned (two female, 11.7 ± 1 yr, 40.4 ± 18 kg, 141.1 ± 9 cm) and eight similar nonburned controls (five female, 12.5 ± 2 yr, 58.0 ± 17 kg, 147.3 ± 12 cm) with comparable exercise capacity (peak oxygen consumption [peak V˙O2]: 31.9 ± 11 vs 36.8 ± 8 mL O2·kg·min, P = 0.39) participated. The exercise protocol entailed a preexercise (pre-EX) rest period followed by 3-min exercise stages at 20 W and 50 W. V˙O2, HR, Q˙ (via nonrebreathing), SV (Q˙/HR), and arteriovenous O2 difference ([a-v]O2diff, Q˙/ V˙O2) were the primary outcome variables. Using a 2-way factorial ANOVA (group [G] × exercise [EX]), we found that Q˙ was approximately 27% lower in the burned than the nonburned group at 20 W of exercise (burned 5.7 ± 1.0 vs nonburned: 7.9 ± 1.8 L·min) and 50 W of exercise (burned 6.9 ± 1.6 vs nonburned 9.2 ± 3.2 L·min) (G-EX interaction, P = 0.012). SV did not change from rest to exercise in burned children but increased by approximately 24% in the nonburned group (main effect for EX, P = 0.046). Neither [a-v] O2diff nor V˙O2 differed between groups at rest or exercise, but HR response to exercise was reduced in the burn group (G-EX interaction, P = 0.004). When normalized to BSA, SV (index) was similar between groups; however, Q˙ (index) remained attenuated in the burned group (G-EX interaction, P exercise. Further investigation of hemodynamic function during exercise will provide insights important for cardiovascular rehabilitation in burned children.

  11. Validation of Peripherally Inserted Central Catheter-Derived Fick Cardiac Outputs in Patients with Heart Failure.

    Science.gov (United States)

    Tecson, Kristen M; Vasudevan, Anupama; Bindra, Amarinder; Joseph, Susan M; Felius, Joost; Hall, Shelley A; Kale, Parag

    2018-01-01

    The pulmonary artery catheter (PAC) remains the gold standard to calculate Fick cardiac outputs (FCOs) in patients with heart failure admitted to the intensive care unit (ICU). The peripherally inserted central catheter (PICC) provides long-term intravenous access and is used outside the ICU; however, there is scant literature validating venous oxygen saturations (VOSs) from PICC lines. Heart failure patients in the ICU with an existing PAC requiring a PICC line to transition were enrolled. Three blood samples were taken per person (1 at PICC, 1 at central venous pressure [CVP], and 1 at distal PAC). We performed repeated measures analysis of variance, as well as reliability analysis on 31 subjects (77% male, 71% Caucasian, mean ± standard deviation age 60 ± 8 years, 80% on inotropes). The average VOSs were 62 ± 11%, 62 ± 12%, and 61 ± 9% for the PICC line, CVP, and distal port, respectively (p = 0.66); there was excellent reliability (0.79). The median FCOs were 5 [4, 6], 5 [4, 6], and 5 [4, 6] L/min at the PICC, CVP, and distal port, respectively (p = 0.91); there was fair-to-good reliability (0.67). In conclusion, VOS and FCO did not differ by location, on average. Reliable data may be obtained through the PICC line, after evaluation from the PAC. The PICC may provide longer-term hemodynamic assessment while improving patient comfort. Copyright © 2017. Published by Elsevier Inc.

  12. Prevalence of lactic acidaemia in patients with advanced heart failure and depressed cardiac output.

    Science.gov (United States)

    Adamo, Luigi; Nassif, Michael E; Novak, Erik; LaRue, Shane J; Mann, Douglas L

    2017-08-01

    Heart failure (HF) has been defined classically as a condition in which the heart is unable to deliver sufficient oxygen to match the needs of the metabolizing tissues. Surprisingly, this definition has never been validated. The goal of this study was to determine the prevalence of elevated lactate levels in a cohort of patients with advanced heart failure. We retrospectively analysed the arterio-venous oxygen difference (A-V O 2 ), haemodynamics, and plasma lactate levels in stage D heart failure patients who were being evaluated for a left ventricular assist device (LVAD). We identified 359 patients with a right heart catheterization (RHC) performed prior to LVAD implantation. Plasma lactate was available for 96 patients. RHC showed that 93% of the patients had an A-V O 2 above the upper limit of normal (>5 mL/100 mL). Among patients with measured lactate levels, the prevalence of elevated lactate (>2.1 mmol/L) was 25% (95% confidence interval 16.7-34.9). The A-V O 2 was widened in all patients with elevated lactate, but plasma lactate did not correlate with A-V O 2 (r = 0.02) and only 27% of patients with increased A-V O 2 had elevated plasma lactate. Lactate levels were normal in ∼75% of the patients with advanced heart failure and a widened A-V O 2 , suggesting that the cardiac output was sufficient to meet the metabolic needs of the peripheral metabolizing tissues. Given that ∼4% of heart failure patients are in NYHA class IV, these findings suggest that the classic definition of heart failure pertains to ∼1% of patients with HF. © 2016 The Authors. European Journal of Heart Failure © 2016 European Society of Cardiology.

  13. Predictors of Post Pericardiotomy Low Cardiac Output Syndrome in Patients With Pericardial Effusion

    Directory of Open Access Journals (Sweden)

    Sabzi Feridoun

    2015-03-01

    Full Text Available Introduction: Pathological involvement of pericardium by any disease that resulting in effusion may require decompression and pericardiectomy. The current article describes rare patients with effusion who after pericadiectomy and transient hemodynamic improvement rapidly developed progressive heart failure and subsequent multi organ failure.Methods: During periods of five years, 423 patients in our hospital underwent pericardiotomy for decompression of effusion. The clinical characteristics of those patient with postoperative low cardiac output (B group (14 cases recorded and compared with other patients without this postoperative complication (A group by test and X2. Significant variables in invariables (P≤0.1 entered in logistic regression analysis and odd ratio of these significant variables obtained. Results: Idiopathic pericardial effusion, malignancy, renal failure, connective tissue disease, viral pericarditis was found in 125 patients (27%, 105 patients (25.4%, 65 patients (15.6%, 50 (17.1% and 10 (2.4% of patients subsequently. The factors that predict post-operative death in logistic regression analysis were malignancy, radiotherapy, constrictive pericarditis inotropic drug using IABP using, pre-operative EF and pericardial calcification.Conclusion: Certain preoperative variables such as malignancy, radiotherapy, low EF, calcified pericardium and connective tissue disease are associated with POLCOS and post-operative risk of death. This paradoxical response to pericardial decompression may be more frequent than currently appreciated. Its cause may relate to the sudden removal of the chronic external ventricular support from the effusion or thicken pericardium resulting in ventricular dilatation and failure or intra operative myocardial injury due to pericardiectomy of calcified pericardium, radiation and cardiomyopathy.

  14. Clinical review: Guyton - the role of mean circulatory filling pressure and right atrial pressure in controlling cardiac output

    OpenAIRE

    Henderson, William R; Griesdale, Donald EG; Walley, Keith R; Sheel, A William

    2010-01-01

    Arthur Guyton's concepts of the determinative role of right heart filling in cardiac output continue to be controversial. This paper reviews his seminal experiments in detail and clarifies the often confusing concepts underpinning his model. One primary criticism of Guyton's model is that the parameters describing venous return had not been measured in a functioning cardiovascular system in humans. Thus, concerns have been expressed in regard to the ability of Guyton's simplistic model, with ...

  15. Prophylactic levosimendan for the prevention of low cardiac output syndrome and mortality in paediatric patients undergoing surgery for congenital heart disease.

    Science.gov (United States)

    Hummel, Johanna; Rücker, Gerta; Stiller, Brigitte

    2017-08-02

    Low cardiac output syndrome remains a serious complication, and accounts for substantial morbidity and mortality in the postoperative course of paediatric patients undergoing surgery for congenital heart disease. Standard prophylactic and therapeutic strategies for low cardiac output syndrome are based mainly on catecholamines, which are effective drugs, but have considerable side effects. Levosimendan, a calcium sensitiser, enhances the myocardial function by generating more energy-efficient myocardial contractility than achieved via adrenergic stimulation with catecholamines. Thus potentially, levosimendan is a beneficial alternative to standard medication for the prevention of low cardiac output syndrome in paediatric patients after open heart surgery. To review the efficacy and safety of the postoperative prophylactic use of levosimendan for the prevention of low cardiac output syndrome and mortality in paediatric patients undergoing surgery for congenital heart disease. We identified trials via systematic searches of CENTRAL, MEDLINE, Embase, and Web of Science, as well as clinical trial registries, in June 2016. Reference lists from primary studies and review articles were checked for additional references. We only included randomised controlled trials (RCT) in our analysis that compared prophylactic levosimendan with standard medication or placebo, in infants and children up to 18 years of age, who were undergoing surgery for congenital heart disease. Two review authors independently extracted data and assessed risk of bias according to a pre-defined protocol. We obtained additional information from all but one of the study authors of the included studies. We used the five GRADE considerations (study limitations, consistency of effect, imprecision, indirectness, and publication bias) to assess the quality of evidence from the studies that contributed data to the meta-analyses for the prespecified outcomes. We created a 'Summary of findings' table to

  16. Femoral Blood Flow and Cardiac Output During Blood Flow Restricted Leg Press Exercise

    Science.gov (United States)

    Everett, M. E.; Hackney, K.; Ploutz-Snyder, L.

    2011-01-01

    Low load blood flow restricted resistance exercise (LBFR) causes muscle hypertrophy that may be stimulated by the local ischemic environment created by the cuff pressure. However, local blood flow (BF) during such exercise is not well understood. PURPOSE: To characterize femoral artery BF and cardiac output (CO) during leg press exercise (LP) performed at a high load (HL) and low load (LL) with different levels of cuff pressure. METHODS: Eleven subjects (men/women 4/7, age 31.4+/-12.8 y, weight 68.9+/-13.2 kg, mean+/-SD) performed 3 sets of supine left LP to fatigue with 90 s of rest in 4 conditions: HL (%1-RM/cuff pressure: 80%/0); LL (20%/0); LBFR(sub DBP) (20%/1.3 x diastolic blood pressure, BP); LBFR(sub SBP) (20%/1.3 x supine systolic BP). The cuff remained inflated throughout the LBFR exercise sessions. Artery diameter, velocity time integral (VTI), and stroke volume (SV) were measured using Doppler ultrasound at rest and immediately after each set of exercise. Heart rate (HR) was monitored using a 3-lead ECG. BF was calculated as VTI x vessel cross-sectional area. CO was calculated as HR x SV. The data obtained after each set of exercise were averaged and used for analyses. Multi-level modeling was used to determine the effect of exercise condition on dependent variables. Statistical significance was set a priori at p LL (9.92+/-0.82 cm3) > LBFR(sub dBP)(6.47+/-0.79 cm3) > LBFR(sub SBP) (3.51+/-0.59 cm3). Blunted exercise induced increases occurred in HR, SV, and CO after LBFR compared to HL and LL. HR increased 45% after HL and LL and 28% after LBFR (p<0.05), but SV increased (p<0.05) only after HL. Consequently, the increase (p<0.05) in CO was greater in HL and LL (approximately 3 L/min) than in LBFR (approximately 1 L/min). CONCLUSION: BF during LBFR(sub SBP) was 1/3 of that observed in LL, which supports the hypothesis that local ischemia stimulates the LBFR hypertrophic response. As the cuff did not compress the artery, the ischemia may have occurred

  17. Usefulness of the Diagnosis "Decreased Cardiac Output (00029)" in Patients With Chronic Heart Failure.

    Science.gov (United States)

    Rojas Sánchez, Lyda Zoraya; Hernández Vargas, Juliana Alexandra; Trujillo Cáceres, Silvia Juliana; Roa Díaz, Zayne Milena; Jurado Arenales, Adriana Milena; Toloza Pérez, Yesith Guillermo

    2017-10-01

    To determine the clinical and construct validity of the nursing diagnosis "decreased cardiac output" (DCO) in patients with chronic heart failure. Cross-sectional study. A total of 200 people were studied. The defining characteristics with the highest prevalence were as follows: arrhythmia (62.5%) and fatigue (61.5%). Adjustment measures such as infit and outfit were maintained between 0.50 and 1.56 and the total variance explained by the measures was 29.3%. This study determined the clinical validity of the nursing diagnosis DCO. Regarding construct validity, adjustment of the defining characteristics to the Rasch model was observed. This study improves the evidence-based practice of nursing and strengthened the role of the nurse who leads care to this population. Determinar la validez clínica y de constructo del diagnóstico de enfermería "Disminución del Gasto Cardíaco" en pacientes con falla cardíaca crónica. MÉTODOS: Estudio de corte transversal. Un total de 200 pacientes fueron estudiados. Las características definitorias con las mayores prevalencias fueron: arritmia (62.5%) y fatiga (61.5%). Medidas de ajuste como el infit y outfit se mantuvieron entre 0.50 y 1.56. El total de la varianza explicada por las medidas fue de 29.3%. Este estudio determinó la validez clínica del diagnóstico de enfermería "Disminución del Gasto Cardíaco". En cuanto a la validez de constructo, se observó que 19 de las 21 características definitorias se ajustaron al modelo Rasch. IMPLICACIONES PARA LA PRÁCTICA DE ENFERMERÍA: Este estudio mejora la práctica basada en la evidencia de enfermería y fortalece el rol de las enfermeras que lideran el cuidado en esta población. © 2016 NANDA International, Inc.

  18. Effect of hemorrhage on cardiac output, vasopressin, aldosterone, and diuresis during immersion in men

    Science.gov (United States)

    Greenleaf, J. E.; Simanonok, K.; Bernauer, E. M.; Wade, C. E.; Keil, L. C.

    1992-01-01

    The purpose of this research was to test the hypotesis that a reduction in blood volume would attenuate or eliminate immersion-induced increases in cardiac output (Q(sub co)) and urine excretion, and to investigate accompanying vasoactive and fluid-electrolyte hormonal responses. Eight men (19-23 yr) were supine during a 2-hr control period in air, and then sat for 5-hr test periods in air at 20 C (dry control, DC); water at 34.5 C (wet control, WC); and water (34.5 C) after hemorrhage (WH) of 14.8 plus or minus 0.3 percent of their blood volume. Blood volume was -11.6 plus or minus 0.6 percent at immersion (time 0). Mean (bar-X hrs 1-5) Q(sub co) was unchanged in WC (5.3 plus or minus 0.01 l/min) and in WH (4.5 plus or minus 0.1 l/min), but decreased (P less than 0.05) in DC to 3.6 plus or minus 0.1 l/min. Mean urine excretion rates were 1.0 plus or minus 0.2 ml/min for DC and 1.1 plus or minus 0.2 ml/min for WH; both were lower (P less than 0.05) than that for WC of 2.0 plus or minus 0.4 ml/min. Plasma (Na+) and (Osm) were unchanged in all experiments. Mean plasma vasopressin (PVP) (bar-X hrs 1-5) was 1.1 plus or minus 0.1 pg/ml in WC, and higher (P less than 0.05) in DC (2.1 plus or minus 0.2 pg/ml)and WH (2.1 plus or minus 0.1 pg/ml); it was unchanged during air and water test periods. Thus, hemorrhage attenuated the immersion-induced increase in Q(sub co), eliminated the WC diuresis, maintained plasma renin activity and PVP at DC levels and did not change immersion-induced aldosterone suppression; the osmotic diuresis during control immersion is apparently not due to either aldosterone suppression or vasopressin suppression.

  19. Low cardiac output predicts development of hepatorenal syndrome and survival in patients with cirrhosis and ascites

    DEFF Research Database (Denmark)

    Krag, A; Bendtsen, F; Møller, S

    2010-01-01

    OBJECTIVES: Recent studies suggest that cardiac dysfunction precedes development of the hepatorenal syndrome. In this follow-up study, we aimed to investigate the relation between cardiac and renal function in patients with cirrhosis and ascites and the impact of cardiac systolic function...... (130 (SD 46) vs 78 (SD 29) mumol/l, phepatorenal syndrome type 1 within 3 months was higher in the group with low CI than in the high CI group (43% vs 5%, p = 0.04). Patients with the lowest CI (N = 8) had significantly poorer survival at 3, 9, and 12 months...

  20. Multiple shooting applied to robust reservoir control optimization including output constraints on coherent risk measures

    DEFF Research Database (Denmark)

    Codas, Andrés; Hanssen, Kristian G.; Foss, Bjarne

    2017-01-01

    . In this work, we propose a new formulation for robust optimization of reservoir well controls. It is inspired by the multiple shooting (MS) method which permits a broad range of parallelization opportunities and output constraint handling. This formulation exploits coherent risk measures, a concept...... traditionally used in finance, to bound the risk on constraint violation. We propose a reduced sequential quadratic programming (rSQP) algorithm to solve the underlying optimization problem. This algorithm exploits the structure of the coherent risk measures, thus a large set of constraints are solved within...... sub-problems. Moreover, a variable elimination procedure allows solving the optimization problem in a reduced space and an iterative active-set method helps to handle a large set of inequality constraints. Finally, we demonstrate the application of constraints to bound the risk of water production...

  1. [Comparison of continuous cardiac output measurement methods: non-invasive estimated CCO using pulse wave transit time and CCO using thermodilution].

    Science.gov (United States)

    Tsutsui, Masato; Yamada, Takashige; Sugo, Yoshihiro; Sato, Tetsufumi; Akazawa, Toshimasa; Sato, Nobukazu; Yamashita, Koichi; Ishihara, Hironori; Kazama, Tomiei; Takeda, Junzo

    2012-09-01

    esCCO (estimated continuous cardiac output, Nihon Kohden, esCCO) is a new cardiac output measurement system which uses pulse wave transit time to calculate cardiac output continuously and non-invasively. One of the most commonly used methods to monitor cardiac output is continuous cardiac output CCO (Edwards Lifesciences) which has an accuracy equivalent to that of thermodilution method. We compared esCCO to CCO in 67 operating room patients and 128 intensive care unit patients. CCO and esCCO were measured simultaneously in patients with a pulmonary artery catheter inserted after admission to the operating room or intensive care unit. CCO and esCCO showed a high correlation with a correlation coefficient of 0.84 in 496 total data points, and 95% limits of agreement between these two methods were -2.49 to 2.35 l x min(-1). This result suggests that esCCO could be used to measure cardiac output accurately and non-invasively in different cases.

  2. Low cardiac output as physiological phenomenon in hibernating, free-ranging Scandinavian brown bears (Ursus arctos) - an observational study.

    Science.gov (United States)

    Jørgensen, Peter Godsk; Arnemo, Jon; Swenson, Jon E; Jensen, Jan S; Galatius, Søren; Frøbert, Ole

    2014-09-16

    Despite 5-7 months of physical inactivity during hibernation, brown bears (Ursus arctos) are able to cope with physiological conditions that would be detrimental to humans. During hibernation, the tissue metabolic demands fall to 25% of the active state. Our objective was to assess cardiac function associated with metabolic depression in the hibernating vs. active states in free-ranging Scandinavian brown bears. We performed echocardiography on seven free-ranging brown bears in Dalarna, Sweden, anesthetized with medetomidine-zolazepam-tiletamine-ketamine during winter hibernation in February 2013 and with medetomidine-zolazepam-tiletamine during active state in June 2013. We measured cardiac output noninvasively using estimates of hemodynamics obtained by pulsed wave Doppler echocardiography and 2D imaging. Comparisons were made using paired T-tests. During hibernation, all hemodynamic indices were significantly decreased (hibernating vs. active state): mean heart rate was 26.0 (standard deviation (SD): 5.6) beats per min vs. 75.0 (SD: 17.1) per min (P=0.002), mean stroke volume 32.3 (SD: 5.2) ml vs. 47.1 (SD: 7.9) ml (P=0.008), mean cardiac output 0.86 (SD: 0.31) l/min vs. 3.54 (SD: 1.04) l/min (P=0.003), and mean cardiac index 0.63 (SD: 0.21) l/min/kg vs. 2.45 (SD: 0.52) l/min/ m2 (Pbears during hibernation, despite the absence of atrial arrhythmias and valvular disease. Free-ranging brown bears demonstrate hemodynamics comparable to humans during active state, whereas during hibernation, we documented extremely low-flow hemodynamics. Understanding these physiological changes in bears may help to gain insight into the mechanisms of cardiogenic shock and heart failure in humans.

  3. The thick left ventricular wall of the giraffe heart normalises wall tension, but limits stroke volume and cardiac output.

    Science.gov (United States)

    Smerup, Morten; Damkjær, Mads; Brøndum, Emil; Baandrup, Ulrik T; Kristiansen, Steen Buus; Nygaard, Hans; Funder, Jonas; Aalkjær, Christian; Sauer, Cathrine; Buchanan, Rasmus; Bertelsen, Mads Frost; Østergaard, Kristine; Grøndahl, Carsten; Candy, Geoffrey; Hasenkam, J Michael; Secher, Niels H; Bie, Peter; Wang, Tobias

    2016-02-01

    Giraffes--the tallest extant animals on Earth--are renowned for their high central arterial blood pressure, which is necessary to secure brain perfusion. Arterial pressure may exceed 300 mmHg and has historically been attributed to an exceptionally large heart. Recently, this has been refuted by several studies demonstrating that the mass of giraffe heart is similar to that of other mammals when expressed relative to body mass. It thus remains unexplained how the normal-sized giraffe heart generates such massive arterial pressures. We hypothesized that giraffe hearts have a small intraventricular cavity and a relatively thick ventricular wall, allowing for generation of high arterial pressures at normal left ventricular wall tension. In nine anaesthetized giraffes (495±38 kg), we determined in vivo ventricular dimensions using echocardiography along with intraventricular and aortic pressures to calculate left ventricular wall stress. Cardiac output was also determined by inert gas rebreathing to provide an additional and independent estimate of stroke volume. Echocardiography and inert gas-rebreathing yielded similar cardiac outputs of 16.1±2.5 and 16.4±1.4 l min(-1), respectively. End-diastolic and end-systolic volumes were 521±61 ml and 228±42 ml, respectively, yielding an ejection fraction of 56±4% and a stroke volume of 0.59 ml kg(-1). Left ventricular circumferential wall stress was 7.83±1.76 kPa. We conclude that, relative to body mass, a small left ventricular cavity and a low stroke volume characterizes the giraffe heart. The adaptations result in typical mammalian left ventricular wall tensions, but produce a lowered cardiac output. © 2016. Published by The Company of Biologists Ltd.

  4. Significant correlation of comprehensive Aristotle score with total cardiac output during the early postoperative period after the Norwood procedure.

    Science.gov (United States)

    Li, Jia; Zhang, Gencheng; Holtby, Helen; Cai, Sally; Walsh, Mark; Caldarone, Christopher A; Van Arsdell, Glen S

    2008-07-01

    The comprehensive Aristotle score has been proposed as an individualized measure of the complexity of a given surgical procedure and has been reported to significantly correlate with postoperative morbidity and mortality after the Norwood procedure. An important factor leading to postoperative morbidity and mortality is low cardiac output. We studied the correlation between the comprehensive Aristotle score and cardiac output (CO) in infants after the Norwood procedure. Respiratory mass spectrometry was used to continuously measure systemic oxygen consumption (VO(2)) in 22 infants for 72 hours postoperatively. Arterial, superior vena caval and pulmonary venous blood gases were measured at 2 to 4 hour intervals to calculate CO. The comprehensive Aristotle score was collected. Hospital mortality was 4.5%. The comprehensive Aristotle score ranged from 14.5 to 23.5 and negatively correlated with CO (P = 0.027). Among the patient-adjusted factors, myocardial dysfunction (n = 10), mechanical ventilation to treat cardiorespiratory failure (n = 9) and atrioventricular valve regurgitation (n = 4) (P = 0.01) negatively correlated with CO (P = 0.06 to 0.07). Aortic atresia (n = 9) was associated with a lower CO (P = 0.01) for the first 24 hours which linearly increased overtime (P = 0.0001). No correlation was found between CO and other factors (P > 0.3 for all). Comprehensive Aristotle score significantly negatively correlates with CO after the Norwood procedure. A preoperative estimation of the comprehensive Aristotle score, particularly in association with myocardial dysfunction, mechanical ventilation to treat cardiorespiratory failure, atrioventricular valve regurgitation and aortic atresia may help to anticipate a high postoperative morbidity with low cardiac output syndrome.

  5. Uncalibrated continuous cardiac output measurement in liver transplant patients: LiDCOrapid™ system versus pulmonary artery catheter.

    Science.gov (United States)

    Costa, Maria Gabriella; Chiarandini, Paolo; Scudeller, Luigia; Vetrugno, Luigi; Pompei, Livia; Serena, Giovanni; Buttera, Stefania; Della Rocca, Giorgio

    2014-06-01

    The aim of the study was to assess the level of agreement between continuous cardiac output estimated by uncalibrated pulse-power analysis (PulseCOLiR) and intermittent (ICO) and continuous cardiac output (CCO) obtained using a pulmonary artery catheter (PAC). Prospective cohort study. University hospital intensive care unit. Twenty patients after liver transplantation. Pulmonary artery catheters were placed in all patients, and ICO and CCO were determined using thermodilution. PulseCOLiR measurements were made using a LiDCOrapid(TM) (LiDCO Ltd, Cambridge, UK). ICO data were determined after intensive care unit admission and every 8 hours until the 48th postoperative hour. CCO and PulseCOLiR measurements were recorded simultaneously at these same time intervals as well as hourly. For the 8-hour data set (140 data pairs), the mean bias and percentage errors (PE) were, respectively,-0.10 L/min and 39.2% for ICO versus PulseCOLiR and 0.79 L/min and 34.6% for CCO versus PulseCOLiR. For the hourly comparison of CCO versus PulseCOLiR (980 data pairs), the bias was 0.75 L/min and the PE 37%. To assess the ability to measure change, a 4-quadrant plot was produced for each pair of methods. The performance of PulseCOLiR was moderate in detecting changes in ICO. In conclusion, the uncalibrated PulseCOLir method should not be used as a substitute for the thermodilution technique for the monitoring of cardiac output in liver transplant patients. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Clinical review: Guyton--the role of mean circulatory filling pressure and right atrial pressure in controlling cardiac output.

    Science.gov (United States)

    Henderson, William R; Griesdale, Donald E G; Walley, Keith R; Sheel, A William

    2010-01-01

    Arthur Guyton's concepts of the determinative role of right heart filling in cardiac output continue to be controversial. This paper reviews his seminal experiments in detail and clarifies the often confusing concepts underpinning his model. One primary criticism of Guyton's model is that the parameters describing venous return had not been measured in a functioning cardiovascular system in humans. Thus, concerns have been expressed in regard to the ability of Guyton's simplistic model, with few parameters, to model the complex human circulation. Further concerns have been raised in regard to the artificial experimental preparations that Guyton used. Recently reported measurements in humans support Guyton's theoretical and animal work.

  7. Pulmonary Artery Catheter (PAC Accuracy and Efficacy Compared with Flow Probe and Transcutaneous Doppler (USCOM: An Ovine Cardiac Output Validation

    Directory of Open Access Journals (Sweden)

    Robert A. Phillips

    2012-01-01

    Full Text Available Background. The pulmonary artery catheter (PAC is an accepted clinical method of measuring cardiac output (CO despite no prior validation. The ultrasonic cardiac output monitor (USCOM is a noninvasive alternative to PAC using Doppler ultrasound (CW. We compared PAC and USCOM CO measurements against a gold standard, the aortic flow probe (FP, in sheep at varying outputs. Methods. Ten conscious sheep, with implanted FPs, had measurements of CO by FP, USCOM, and PAC, at rest and during intervention with inotropes and vasopressors. Results. CO measurements by FP, PAC, and USCOM were 4.0±1.2 L/min, 4.8±1.5 L/min, and 4.0±1.4 L/min, respectively, (=280, range 1.9 L/min to 11.7 L/min. Percentage bias and precision between FP and PAC, and FP and USCOM was −17 and 47%, and 1 and 36%, respectively. PAC under-measured Dobutamine-induced CO changes by 20% (relative 66% compared with FP, while USCOM measures varied from FP by 3% (relative 10%. PAC reliably detected −30% but not +40% CO changes, as measured by receiver operating characteristic area under the curve (AUC, while USCOM reliably detected ±5% changes in CO (AUC>0.70. Conclusions. PAC demonstrated poor accuracy and sensitivity as a measure of CO. USCOM provided equivalent measurements to FP across a sixfold range of outputs, reliably detecting ±5% changes.

  8. Prevalence of nursing diagnosis of decreased cardiac output and the predictive value of defining characteristics in patients under evaluation for heart transplant.

    Science.gov (United States)

    Matos, Lígia Neres; Guimarães, Tereza Cristina Felippe; Brandão, Marcos Antônio Gomes; Santoro, Deyse Conceição

    2012-01-01

    The purposes of the study were to identify the prevalence of defining characteristics (DC) of decreased cardiac output (DCO) in patients with cardiac insufficiency under evaluation for heart transplantation, and to ascertain the likelihood of defining characteristics being predictive factors for the existence of reduction in cardiac output. Data was obtained by retrospective documental analysis of the clinical records of right-sided heart catheterizations in 38 patients between 2004 and 2009. The results showed that 71.1% of the patients had decreased cardiac output (measured by cardiac index). The majority of the NANDA-International defining characteristics for DCO were more frequent in individuals with reduced cardiac index levels. The study emphasizes the odds ratio (OR) for increased Systemic Vascular Resistance of OR=4.533, of the third heart sound with OR=3.429 and the reduced ejection fraction with OR=2.850. By obtaining the predictive values for the defining characteristics the study identifies them as diagnostic indicators of decreased cardiac output.

  9. The decrease of cardiac chamber volumes and output during positive-pressure ventilation

    DEFF Research Database (Denmark)

    Kristensen, Kasper Kyhl; Ahtarovski, Kiril Aleksov; Iversen, Kasper

    2013-01-01

    ) ml (P heart rate increased by 7 (±2) beats/min; and CO decreased by 1.0 (±0.4) l/min (P right and left ventricular peak filling rates decreased......Positive-pressure ventilation (PPV) is widely used for treatment of acute cardiorespiratory failure, occasionally at the expense of compromised cardiac function and arterial blood pressure. The explanation why has largely rested on interpretation of intracardiac pressure changes. We evaluated...

  10. Clinical usefulness of the definitions for defining characteristics of activity intolerance, excess fluid volume and decreased cardiac output in decompensated heart failure: a descriptive exploratory study.

    Science.gov (United States)

    de Souza, Vanessa; Zeitoun, Sandra Salloum; Lopes, Camila Takao; de Oliveira, Ana Paula Dias; Lopes, Juliana de Lima; de Barros, Alba Lucia Bottura Leite

    2015-09-01

    To assess the clinical usefulness of the operational definitions for the defining characteristics of the NANDA International nursing diagnoses, activity intolerance, decreased cardiac output and excess fluid volume, and the concomitant presence of those diagnoses in patients with decompensated heart failure. Content validity of the operational definitions for the defining characteristics of activity intolerance, excess fluid volume and decreased cardiac output have been previously validated by experts. Their clinical usefulness requires clinical validation. This was a descriptive exploratory study. Two expert nurses independently assessed 25 patients with decompensated heart failure for the presence or absence of 29 defining characteristics. Interrater reliability was analysed using the Kappa coefficient as a measure of clinical usefulness. The Fisher's exact test was used to test the association of the defining characteristics of activity intolerance and excess fluid volume in the presence of decreased cardiac output, and the correlation between the three diagnoses. Assessments regarding the presence of all defining characteristics reached 100% agreement, except with anxiety. Five defining characteristics of excess fluid volume were significantly associated with the presence of decreased cardiac output. Concomitant presence of the three diagnoses occurred in 80% of the patients. However, there was no significant correlation between the three diagnoses. The operational definitions for the diagnoses had strong interrater reliability, therefore they were considered clinically useful. Only five defining characteristics were representative of the association between excess fluid volume and decreased cardiac output. Therefore, excess fluid volume is related to decreased cardiac output, although these diagnoses are not necessarily associated with activity intolerance. The operational definitions may favour early recognition of the sequence of responses to decompensation

  11. In vitro, in vivo and numerical assessment of the working principle of the truCCOMS continuous cardiac output catheter system.

    Science.gov (United States)

    Claessens, T; Verwilst, P; Missant, C; Claus, P; Verdonck, P; Wouters, P; Segers, P

    2009-12-01

    The truCCOMS cardiac output monitor system provides a continuous and instantaneous measurement of cardiac output, derived from the amount of energy required for heating a filament to maintain a fixed 2 degrees C blood temperature difference between two thermistors located distally on a pulmonary artery catheter. Clinical studies, however, reported relatively poor accuracy of the cardiac output estimation, possibly due to linearly assumed power-cardiac output relationship used for calibration of the catheters. We experimentally studied the shape of the truCCOMS calibration relationship (i) in a hydraulic bench model of the right heart and (ii) in vivo intact animal model. The results showed a nonlinear relationship between the power input into the heating element and the cardiac output; which could satisfactorily be described with an exponential relationship. Comparison of the performance of the same catheters in vitro and in vivo showed that the in vitro determined calibration relationship should not be used for in vivo measurements. Finally, we also simulated the working principle of the catheter using a simplified numerical model of the blood flow and heat transfer around the catheter. The computed results also suggested a pronounced nonlinear relationship between power and cardiac output in pulsatile conditions. We conclude that the observed over- and underestimation of high- and low flows, respectively, by the current truCCOMS system is likely to arise from its linear calibration relationship. An appropriate calibration scheme accounting for the intrinsic nonlinear power-cardiac output relationship and the difference between in vitro and in vivo conditions should improve the clinical performance of the system.

  12. Experience with Mechanical Circulatory Support for Medically Intractable Low Cardiac Output in a Pediatric Intensive Care Unit.

    Science.gov (United States)

    Park, Jung Bin; Kwak, Jae Gun; Lim, Hong-Gook; Kim, Woong-Han; Lee, Jeong Ryul; Kim, Yong Jin

    2017-07-01

    Mechanical circulatory support with extracorporeal membrane oxygenation (ECMO) and ventricular assist device has always been the optimal choice for treating the majority of medically intractable low cardiac output case. We retrospectively investigated our institution's outcomes and variables associated with a high risk of mortality. From 1999 to 2014, 86 patients who were of pediatric age or had grown-up congenital heart disease underwent mechanical circulatory support for medically intractable low cardiac output in our pediatric intensive care unit. Of these, 9 grown-up congenital heart disease patients were over 18 years of age, and the median age of the subject group was 5.82 years (range: 1 day to 41.6 years). A review of all demographic, clinical, and surgical data and survival analysis were performed. A total of 45 (52.3%) patients were successfully weaned from the mechanical assist device, and 25 (29.1%) survivors were able to be discharged. There was no significant difference in results between patients over 18 years and under 18 years of age. Risk factors for mortality were younger age (metabolic acidosis and increased levels of lactate, creatinine, bilirubin, or liver enzyme). The survival rate has improved since 2010 (from 25% before 2010 to 35% after 2010), when we introduced an upgraded oxygenator, activated heart transplantation, and also began to apply ECMO before the end-stage of cardiac dysfunction, even though we could not reveal significant correlations between survival rate and changed strategies associated with ECMO. Mechanical circulatory support has played a critical role and has had a dramatic effect on survival in patients with medically intractable heart failure, particularly in recent years. Meticulous monitoring of acid-base status, laboratory findings, and early and liberal applications are recommended to improve outcomes without critical complication rates, particularly in neonates with single ventricle physiology.

  13. Arterial pressure-based cardiac output in septic patients: different accuracy of pulse contour and uncalibrated pressure waveform devices.

    Science.gov (United States)

    Monnet, Xavier; Anguel, Nadia; Naudin, Brice; Jabot, Julien; Richard, Christian; Teboul, Jean-Louis

    2010-01-01

    We compared the ability of two devices estimating cardiac output from arterial pressure-curve analysis to track the changes in cardiac output measured with transpulmonary thermodilution induced by volume expansion and norepinephrine in sepsis patients. In 80 patients with septic circulatory failure, we administered volume expansion (40 patients) or introduced/increased norepinephrine (40 patients). We measured the pulse contour-derived cardiac index (CI) provided by the PiCCO device (CIpc), the arterial pressure waveform-derived CI provided by the Vigileo device (CIpw), and the transpulmonary thermodilution CI (CItd) before and after therapeutic interventions. The changes in CIpc accurately tracked the changes in CItd induced by volume expansion (bias, -0.20 +/- 0.63 L/min/m2) as well as by norepinephrine (bias, -0.05 +/- 0.74 L/min/m2). The changes in CIpc accurately detected an increase in CItd >or= 15% induced by volume expansion and norepinephrine introduction/increase (area under ROC curves, 0.878 (0.736 to 0.960) and 0.924 (0.795 to 0.983), respectively; P or= 15% induced by volume expansion and norepinephrine introduction/increase (area under ROC curves, 0.564 (0.398 to 0.720) and 0.541 (0.377 to 0.700, respectively, both not significantly different from versus 0.500). The CIpc was reliable and accurate for assessing the CI changes induced by volume expansion and norepinephrine. By contrast, the CIpw poorly tracked the trends in CI induced by those therapeutic interventions.

  14. Cerebral tissue oxygenation index, cardiac output and superior vena cava flow in infants with birth weight less than 1250 grams in the first 48 hours of life.

    Science.gov (United States)

    Sirc, J; Dempsey, E M; Miletin, J

    2013-07-01

    Near-infrared spectroscopy is a non-invasive method of assessing cerebral oxygenation. Functional echocardiography is increasingly used by neonatologists in the assessment of cardiovascular function. To correlate cerebral tissue oxygenation index (cTOI) and cardiac output in infants less than 1250 g at 6, 12, 24 and 48 hours of age. A prospective observational study. Newborns with birth weightoutputs, ductus arteriosus and cTOI were performed at 6, 12, 24 and 48 hours of age. Clinical parameters, including mean blood pressure, mean airway pressure, blood gas parameters and oxygen saturations were recorded. 22 neonates were enrolled following parental consent. The mean birth weight was 851 g (SD±201), mean gestational age was 25.9 weeks (SD±1.7). Mean SVC flow at 6 hours of age was 56.8 ml/kg/min and increased to 68.6 ml/kg/min at 48 hours of age. 9 infants (41%) had at least one measurement of low SVC flow (output increased during first 48 hours of life. cTOI decreased at 12 hours of age with a concomitant increase in fractionated oxygen extraction. These changes reflect transitional changes in both cardiac and cerebral hemodynamics in extremely low gestational age newborns during the first 48 hours. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Plasma volume expansion does not increase maximal cardiac output or VO2 max in lowlanders acclimatized to altitude

    DEFF Research Database (Denmark)

    Calbet, José A L; Rådegran, Göran; Boushel, Robert Christopher

    2004-01-01

    liter of 6% dextran 70 (BV = 6.32 +/- 0.34 liters). PV expansion had no effect on Qmax, maximal O2 consumption (VO2), and exercise capacity. Despite maximal systemic O2 transport being reduced 19% due to hemodilution after PV expansion, whole body VO2 was maintained by greater systemic O2 extraction (P...... VO2 during exercise regardless of PV. Pulmonary ventilation, gas exchange, and acid-base balance were essentially unaffected by PV expansion. Sea......With altitude acclimatization, blood hemoglobin concentration increases while plasma volume (PV) and maximal cardiac output (Qmax) decrease. This investigation aimed to determine whether reduction of Qmax at altitude is due to low circulating blood volume (BV). Eight Danish lowlanders (3 females, 5...

  16. Measurement of cardiac output during exercise in healthy, trained humans using lithium dilution and pulse contour analysis

    International Nuclear Information System (INIS)

    Elliott, Adrian D; Skowno, Justin; Prabhu, Mahesh; Ansley, Les

    2012-01-01

    The aim of this study was to evaluate the use of pulse contour analysis calibrated with lithium dilution in a single device (LiDCO™) for measurement of cardiac output (.Q) during exercise in healthy volunteers. We sought to; (a) compare pulse contour analysis (PulseCO) and lithium indicator dilution (LiDCO) for the measurement of .Q during exercise, and (b) assess the requirement for recalibration of PulseCO with LiDCO during exercise. Ten trained males performed multi-stage cycling exercise at intensities below and above ventilatory threshold before constant load maximal exercise to exhaustion. Uncalibrated PulseCO .Q (.Q raw ) was compared to that calibrated with lithium dilution at baseline (.Q baseline ), during submaximal exercise below (.Q low ) and above (.Q high ) ventilatory threshold, and at each exercise stage individually (.Q exercise ). There was a significant difference between .Q baseline and all other calibration methods during exercise, but not at rest. No significant differences were observed between other methods. Closest agreement with .Q exercise was observed for .Q high (bias ± limits of agreement: 4.8 ± 30.0%). The difference between .Q exercise and both .Q low and .Q raw was characterized by low bias (4–7%) and wide limits of agreement (>±40%). Calibration of pulse contour analysis with lithium dilution prior to exercise leads to a systematic overestimation of exercising cardiac output. A single calibration performed during exercise above the ventilatory threshold provided acceptable limits of agreement with an approach incorporating multiple calibrations throughout exercise. Pulse contour analysis may be used for .Q measurement during exercise providing the system is calibrated during exercise. (paper)

  17. Evaluation of noninvasive exercise cardiac output determination in chronic heart failure patients: a proposal of a new diagnostic and prognostic method.

    Science.gov (United States)

    Cattadori, Gaia; Salvioni, Elisabetta; Gondoni, Erica; Agostoni, Piergiuseppe

    2011-01-01

    Peak oxygen consumption (VO2) and various parameters of cardiopulmonary response to exercise are of important prognostic value in chronic heart failure patients. However, all the available parameters only indirectly reflect left-ventricular dysfunction and hemodynamic adaptation to an increased demand. Noninvasive assessment of cardiac output, especially during an incremental exercise test, would allow the direct measurement of cardiac reserve and may become the gold standard for prognostic evaluation of chronic heart failure patients.

  18. Critical incidents, including cardiac arrest, associated with pediatric anesthesia at a tertiary teaching children's hospital.

    Science.gov (United States)

    Lee, Ji-Hyun; Kim, Eun-Kyung; Song, In-Kyung; Kim, Eun-Hee; Kim, Hee-Soo; Kim, Chong-Sung; Kim, Jin-Tae

    2016-04-01

    Analysis of critical incidents provides valuable information to improve the quality and safety of patient care. This study identified and analyzed pediatric anesthesia-related critical incidents including cardiac arrests in a tertiary teaching children's hospital. All pediatric anesthesia-related critical incidents reported in a voluntary departmental reporting system between January 2008 and August 2013 were included in the analysis. A critical incident was defined as (i) any incident that altered patients' vital signs and affected the management of patients while they were under the care of an anesthesiologist, and (ii) human factor: where patient injury or accidents were as a result of human error. Changes in vital signs that recovered spontaneously were excluded. During the 6-year study period, a total of 229 critical incidents were reported from 49,373 anesthetic procedures. The most frequently reported incidents were associated with the respiratory system (55%), with tracheal tube-related events accounting for 40.9% of respiratory incidents followed by laryngospasm (17.3% of respiratory incidents). Cardiac arrest occurred in 42 cases in this study (8.5 cases per 10,000 anesthetics). Cardiovascular problems were the major causes of cardiac arrest (66.7%), and incidents of cardiogenic shock and hemorrhage/hypotension contributed equally to the cardiac arrest induced by cardiovascular problems (each 16.7%). Human factor-related events accounted for 58.5% of all critical incidents of which 53.7% were respiratory events. Despite recent improvements in safety of pediatric anesthesia, many preventable factors still remain that can lead to critical incidents. © 2016 John Wiley & Sons Ltd.

  19. The Higher the Insulin Resistance the Lower the Cardiac Output in Men with Type 1 Diabetes During the Maximal Exercise Test.

    Science.gov (United States)

    Niedzwiecki, Pawel; Naskret, Dariusz; Pilacinski, Stanislaw; Pempera, Maciej; Uruska, Aleksandra; Adamska, Anna; Zozulinska-Ziolkiewicz, Dorota

    2017-06-01

    The aim of this study was to assess the hemodynamic parameters analyzed in bioimpedance cardiography during maximal exercise in patients with type 1 diabetes differing in insulin resistance. The study group consisted of 40 men with type 1 diabetes. Tissue sensitivity to insulin was assessed on the basis of the glucose disposal rate (GDR) analyzed during hyperinsulinemic-euglycemic clamp. Patients were divided into groups with GDR insulin sensitivity) and GDR ≥4.5 mg/kg/min (G2 group-higher insulin sensitivity). During the exercise test, the heart rate, systolic volume, cardiac output, cardiac index were measured by the impedance meter (PhysioFlow). Compared with the G2 group, the G1 group had a lower cardiac output (CO): during exercise 8.6 (IQR 7.7-10.0) versus 12.8 (IQR 10.8-13.7) L/min; P insulin resistance is associated with cardiac hemodynamic parameters assessed during and after exercise. The higher the insulin resistance the lower the cardiac output during maximal exercise in men with type 1 diabetes.

  20. Cardiac output measurement in ventilated lambs with a significant left-to-right shunt using the modified carbon dioxide fick method.

    NARCIS (Netherlands)

    Boode, W.P. de; Hopman, J.C.W.; Wijnen, M.H.W.A.; Tanke, R.B.; Hoeven, J.G. van der; Liem, K.D.

    2010-01-01

    BACKGROUND: It remains a great challenge to measure systemic blood flow in critically ill newborns. In a former study we validated the modified carbon dioxide Fick (mCO(2)F) method for measurement of cardiac output in a newborn lamb model. In this new study we studied the influence of a

  1. Cardiac output measurement with transpulmonary ultrasound dilution is feasible in the presence of a left-to-right shunt: a validation study in lambs.

    NARCIS (Netherlands)

    Vrancken, S.L.A.G.; Boode, W.P. de; Hopman, J.C.W.; Singh, S.; Liem, K.D.; Heyst, A.F.J. van

    2012-01-01

    BACKGROUND: Cardiac output (CO) monitoring remains complex in newborns as most of the current technologies fail to accurately measure systemic blood flow in the presence of shunts. We validated CO measurements using transpulmonary ultrasound dilution (TPUD) in a neonatal lamb model with a

  2. Changes in Total Cardiac Output and Oxygen Extraction During Exercise in Patients Supported With an HVAD Left Ventricular Assist Device.

    Science.gov (United States)

    Schmidt, Thomas; Bjarnason-Wehrens, Birna; Mommertz, Stephanie; Hannig, Meike; Schulte-Eistrup, Sebastian; Willemsen, Detlev; Reiss, Nils

    2018-02-12

    Following implantation of a left ventricular assist device (LVAD), acceptable functional performance is now being achieved; however, peak VO 2 and peak work load (watts) remain considerably limited. Maximum physical capacity is essentially dependent on generated cardiac output (CO) and arteriovenous oxygen difference (avDO 2 ). We investigated the changes in CO and avDO 2 during exercise in LVAD patients with an HVAD pump (HeartWare Inc., Framingham, MA, USA). Approximately 6 weeks after implantation, 20 patients (100% male, 60.8 ± 7.3 years old, BMI 25.7 ± 3.3) underwent a six-minute walk test (6MWT), a cardiopulmonary exercise test (CPET), and noninvasive hemodynamic measurement. The mean six-minute walking distance (6MWD) was 403 m (68% of predicted), and mean peak VO 2 was 10.9 mL/kg/min (39% of predicted). Mean total CO improved from 3.8 L at rest to 7.0 L at maximum exercise. The mean avDO 2 increased from 7.4 mL/dL (44% of oxygen content) at rest to 13.2 mL/dL (75% of oxygen content) at maximum exercise. There was a significant increase in both total CO (P parameters. © 2018 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  3. Use of cardiac output to improve measurement of input function in quantitative dynamic contrast-enhanced MRI.

    Science.gov (United States)

    Zhang, Jeff L; Rusinek, Henry; Bokacheva, Louisa; Chen, Qun; Storey, Pippa; Lee, Vivian S

    2009-09-01

    To validate a new method for converting MR arterial signal intensity versus time curves to arterial input functions (AIFs). The method constrains AIF with patient's cardiac output (Q). Monte Carlo simulations of MR renography and tumor perfusion protocols were carried out for comparison with two alternative methods: direct measurement and population-averaged input function. MR renography was performed to assess the method's inter- and intraday reproducibility for renal parameters. In simulations of tumor perfusion, the precision of the parameters (K(trans) and v(e)) computed using the proposed method was improved by at least a factor of three compared to direct measurement. Similar improvements were obtained in simulations of MR renography. Volunteer study for testing interday reproducibility confirmed the improvement of precision in renal parameters when using the proposed method compared to conventional methods. In another patient study (two injections within one session), the proposed method significantly increased the correlation coefficient (R) between GFR of the two exams (0.92 vs. 0.83) compared to direct measurement. A new method significantly improves the precision of dynamic contrast-enhanced (DCE) parameters. The method may be especially useful for analyzing repeated DCE examinations, such as monitoring tumor therapy or angiotensin converting enzyme-inhibitor renography.

  4. Corrective effect of diaphragm pacing on the decrease in cardiac output induced by positive pressure mechanical ventilation in anesthetized sheep.

    Science.gov (United States)

    Masmoudi, Hicham; Persichini, Romain; Cecchini, Jérôme; Delemazure, Julie; Dres, Martin; Mayaux, Julien; Demoule, Alexandre; Assouad, Jalal; Similowski, Thomas

    2017-02-01

    Positive pressure ventilation (PPV) is a fundamental life support measure, but it decreases cardiac output (CO). Diaphragmatic contractions produce negative intrathoracic and positive abdominal pressures, promoting splanchnic venous return. We hypothesized that: 1) diaphragm pacing alone could produce adequate ventilation without decreasing CO; 2) diaphragm pacing on top of PPV could improve CO. Of 11 anesthetized and mechanically ventilated ewes (39.6±5.9kg), 3 were discarded from analysis because of hemodynamic instability during the experiment, and 8 retained for analysis. Phrenic stimulation electrodes were inserted in the diaphragm (implanted phrenic nerve stimulation, iPS). CO was measured by the thermodilution technique (pulmonary artery catheter). CO during end-expiratory apnea served as reference. Median CO was 9.77 [6.25-11.25] lmin -1 during end-expiratory apnea, 8.25 [5.06-9.25] lmin -1 during "PPV" (-15%) (pventilation was comparable to its PPV counterpart (median 92% [74-97], NS). Diaphragm pacing alone can produce adequate ventilation without reducing CO. Superimposed onto PPV, diaphragm pacing can reduce the PPV-induced decrease in CO. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Cardiac output-based fluid optimization for kidney transplant recipients: a proof-of-concept trial.

    Science.gov (United States)

    Corbella, Davide; Toppin, Patrick Jason; Ghanekar, Anand; Ayach, Nour; Schiff, Jeffery; Van Rensburg, Adrian; McCluskey, Stuart A

    2018-04-10

    Intravenous fluid management for deceased donor kidney transplantation is an important, modifiable risk factor for delayed graft function (DGF). The primary objective of this study was to determine if goal-directed fluid therapy using esophageal Doppler monitoring (EDM) to optimize stroke volume (SV) would alter the amount of fluid given. This randomized, proof-of-concept trial enrolled 50 deceased donor renal transplant recipients. Data collected included patient characteristics, fluid administration, hemodynamics, and complications. The EDM was used to optimize SV in the EDM group. In the control group, fluid management followed the current standard of practice. The groups were compared for the primary outcome of total intraoperative fluid administered. There was no difference in the mean (standard deviation) volume of intraoperative fluid administered to the 24 control and 26 EDM patients [2,307 (750) mL vs 2,675 (842) mL, respectively; mean difference, 368 mL; 95% confidence interval (CI), - 87 to + 823; P = 0.11]. The incidence of complications in the control and EDM groups was similar (15/24 vs 17/26, respectively; P = 0.99), as was the incidence of delayed graft failure (8/24 vs 11/26, respectively; P = 0.36). Goal-directed fluid therapy did not alter the volume of fluid administered or the incidence of complications. This proof-of-concept trial provides needed data for conducting a larger trial to determine the influence of fluid therapy on the incidence in DGF in deceased donor kidney transplantation. www.clinicaltrials.gov (NCT02512731). Registered 31 July 2015.

  6. Diesel Exhaust Inhalation Increases Cardiac Output, Bradyarrhythmias, and Parasympathetic Tone in Aged Heart Failure-Prone Rats

    Science.gov (United States)

    Acute air pollutant inhalation is linked to adverse cardiac events and death, and hospitalizations for heart failure. Diesel exhaust (DE) is a major air pollutant suspected to exacerbate preexisting cardiac conditions, in part, through autonomic and electrophysiologic disturbance...

  7. Clinical validation of a real-time data processing system for cardiac output and arterial pressure measurement during intraoperative biventricular pacing optimization.

    Science.gov (United States)

    Johnson, Christopher K; Cabreriza, Santos E; Sahar, Rana L; Rusanov, Alexander; Wang, Daniel Y; Cheng, Bin; Gendy, Mira S; Quinn, T Alexander; Spotnitz, Henry Michael

    2012-01-01

    Biventricular pacing (BiVP) improves cardiac output (CO) and mean arterial pressure (MAP) after cardiopulmonary bypass (CPB) in selected patients at risk for acute left heart failure after cardiac surgery. Optimization of atrioventricular delay (AVD) and interventricular delay (VVD) to maximize the hemodynamic effect of pacing requires rapid and accurate data processing. Conventional post hoc data processing (PP) is accurate but time-consuming, and infeasible in the intraoperative setting. We created a customized, real-time data processing (RTP) system to improve data processing efficiency, while maintaining accuracy. Biventricular pacing optimization was performed within 1 hour of the conclusion of CPB in 10 patients enrolled in the Biventricular Pacing After Cardiac Surgery trial. Cardiac output, measured by an electromagnetic flow meter, and arterial pressure were recorded as AVD was randomly varied across seven settings and VVD across nine settings. Post hoc data processing values calculated by two observers were compared to RTP-generated outputs for CO and MAP. Interexaminer reliability coefficients were generated to access the dependability of RTP. Interexaminer reliability coefficient values ranged from 0.997 to 0.999, indicating RTP is as reliable as PP for optimization. Real-time data processing is instantaneous and therefore is more practical in a clinical setting than the PP method. Real-time data processing is useful for guiding intraoperative BiVP optimization and merits further development.

  8. [Effects of application of pulse contour cardiac output monitoring technology in early treatment of patients with large area burns].

    Science.gov (United States)

    Wang, D Y; Xie, W G; Xi, M M; Li, Z; Wang, B

    2018-01-20

    Objective: To analyze the changes and relationship of early hemodynamic indexes of patients with large area burns monitored by pulse contour cardiac output (PiCCO) monitoring technology, so as to assess the guiding value of this technology in the treatment of patients with large area burns during shock period. Methods: Eighteen patients with large area burns, confirming to the study criteria, were admitted to our unit from May 2016 to May 2017. Pulse contour cardiac output index (PCCI), systemic vascular resistance index (SVRI), global end-diastolic volume index (GEDVI), and extravascular lung water index (EVLWI) of patients were monitored by PiCCO instrument from admission to post injury day (PID) 7, and they were calibrated and recorded once every four hours. The fluid infusion coefficients of patients at the first and second 24 hours post injury were calculated. The blood lactic acid values of patients from PID 1 to 7 were also recorded. The correlations among PCCI, SVRI, and GEDVI as well as the correlation between SVRI and blood lactic acid of these 18 patients were analyzed. Prognosis of patients were recorded. Data were processed with one-way analysis of variance, single sample t test and Bonferroni correction, Pearson correlation analysis, and Spearman rank correlation analysis. Results: (1) There was statistically significant difference in PCCI value of patients from post injury hour (PIH) 4 to 168 ( F =7.428, P 0.05). (2) There was statistically significant difference in SVRI value of patients from PIH 4 to 168 ( F =7.863, P 0.05). (3) There was no statistically significant difference in the GEDVI values of patients from PIH 4 to 168 ( F =0.704, P >0.05). The GEDVI values of patients at PIH 8, 12, 16, 20, and 24 were significantly lower than normal value ( t =-3.112, -3.554, -2.969, -2.450, -2.476, P 0.05). (4) There was statistically significant difference in EVLWI value of patients from PIH 4 to 168 ( F =1.859, P 0.05). (5) The fluid infusion

  9. Does obesity affect the non-invasive measurement of cardiac output performed by electrical cardiometry in children and adolescents?

    Science.gov (United States)

    Altamirano-Diaz, Luis; Welisch, Eva; Rauch, Ralf; Miller, Michael; Park, Teresa Sohee; Norozi, Kambiz

    2018-02-01

    Electrical cardiometry (EC) is a non-invasive and inexpensive method for hemodynamic assessment and monitoring. However, its feasibility for widespread clinical use, especially for the obese population, has yet to be determined. In this study, we evaluated the agreement and reliability of EC compared to transthoracic Doppler echocardiography (TTE) in normal, overweight, and obese children and adolescents. We measured stroke volume (SV) and cardiac output (CO) of 131 participants using EC and TTE simultaneously. We further divided these participants according to BMI percentiles for subanalyses: 95% obese (n = 83). Due to small sample size of the overweight group, we combined overweight and obese groups (OW+OB) with no significant change in results (SV and CO) before and after combining groups. There were strong correlations between EC and TTE measurements of SV (r = 0.869 and r = 0.846; p < 0.0001) and CO (r = 0.831 and r = 0.815; p < 0.0001) in normal and OW+OB groups, respectively. Bias and percentage error for CO measurements were 0.240 and 29.7%, and 0.042 and 29.5% in the normal and OW+OB groups, respectively. Indexed values for SV were lower in the OW+OB group than in the normal weight group when measured by EC (p < 0.0001) but no differences were seen when measured by TTE (p = 0.096). In all weight groups, there were strong correlations and good agreement between EC and TTE. However, EC may underestimate hemodynamic measurements in obese participants due to fat tissue.

  10. Assessment of interchangeability rate between 2 methods of measurements: An example with a cardiac output comparison study.

    Science.gov (United States)

    Lorne, Emmanuel; Diouf, Momar; de Wilde, Robert B P; Fischer, Marc-Olivier

    2018-02-01

    The Bland-Altman (BA) and percentage error (PE) methods have been previously described to assess the agreement between 2 methods of medical or laboratory measurements. This type of approach raises several problems: the BA methodology constitutes a subjective approach to interchangeability, whereas the PE approach does not take into account the distribution of values over a range. We describe a new methodology that defines an interchangeability rate between 2 methods of measurement and cutoff values that determine the range of interchangeable values. We used a simulated data and a previously published data set to demonstrate the concept of the method. The interchangeability rate of 5 different cardiac output (CO) pulse contour techniques (Wesseling method, LiDCO, PiCCO, Hemac method, and Modelflow) was calculated, in comparison with the reference pulmonary artery thermodilution CO using our new method. In our example, Modelflow with a good interchangeability rate of 93% and a cutoff value of 4.8 L min, was found to be interchangeable with the thermodilution method for >95% of measurements. Modelflow had a higher interchangeability rate compared to Hemac (93% vs 86%; P = .022) or other monitors (Wesseling cZ = 76%, LiDCO = 73%, and PiCCO = 62%; P < .0001). Simulated data and reanalysis of a data set comparing 5 CO monitors against thermodilution CO showed that, depending on the repeatability of the reference method, the interchangeability rate combined with a cutoff value could be used to define the range of values over which interchangeability remains acceptable.

  11. Inspiratory Muscle Training Is Associated With Improved Inspiratory Muscle Strength, Resting Cardiac Output, and the Ventilatory Efficiency of Exercise in Patients With a Fontan Circulation.

    Science.gov (United States)

    Laohachai, Karina; Winlaw, David; Selvadurai, Hiran; Gnanappa, Ganesh Kumar; d'Udekem, Yves; Celermajer, David; Ayer, Julian

    2017-08-21

    Patients with a Fontan circulation have reduced exercise capacity and respiratory muscle strength. Inspiratory muscle training (IMT) improves exercise capacity and quality of life in adults with heart failure. We assessed whether 6 weeks of a home-based program of IMT improves inspiratory muscle strength and the ventilatory efficiency of exercise in adolescent patients with a Fontan circulation. Twenty-three adolescent participants (aged 16±2 years) with a Fontan circulation underwent 6 weeks of IMT for 30 minutes daily. Respiratory muscle strength (maximal inspiratory pressure and expiratory pressure), lung function, and exercise capacity (cardiopulmonary exercise testing) were assessed. Fourteen of 23 participants also underwent exercise cardiac magnetic resonance imaging to examine the effects of IMT on cardiac output and systemic and pulmonary blood flow. Six weeks of IMT improved maximal inspiratory pressure by 36±24 cm H 2 O (61±46%) with no change in maximal expiratory pressure. Ventilatory efficiency of exercise improved after 6 weeks of IMT (from 34.2±7.8 to 32.2±5.6, P =0.04). In those who underwent exercise cardiac magnetic resonance imaging, IMT increased resting cardiac output (from 4.2±1.2 to 4.5±1.0 L/min, P =0.03) and ejection fraction (from 50.1±4.3 to 52.8±6.1%, P =0.03). Six weeks of IMT is associated with improved inspiratory muscle strength, ventilatory efficiency of exercise, and resting cardiac output in young Fontan patients. IMT may be a simple beneficial addition to the current management of Fontan patients, potentially reducing exercise intolerance and long-term morbidity and mortality. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  12. Cardiac gated ventilation

    Science.gov (United States)

    Hanson, C. William, III; Hoffman, Eric A.

    1995-05-01

    There are several theoretic advantages to synchronizing positive pressure breaths with the cardiac cycle, including the potential for improving distribution of pulmonary and myocardial blood flow and enhancing cardiac output. We evaluated the effects of synchronizing respiration to the cardiac cycle using a programmable ventilator and electron beam CT (EBCT) scanning. The hearts of anesthetized dogs were imaged during cardiac gated respiration with a 50msec scan aperture. Multislice, short axis, dynamic image data sets spanning the apex to base of the left ventricle were evaluated to determine the volume of the left ventricular chamber at end-diastole and end-systole during apnea, systolic and diastolic cardiac gating. We observed an increase in cardiac output of up to 30% with inspiration gated to the systolic phase of the cardiac cycle in a nonfailing model of the heart.

  13. Change in end-tidal carbon dioxide outperforms other surrogates for change in cardiac output during fluid challenge.

    Science.gov (United States)

    Lakhal, K; Nay, M A; Kamel, T; Lortat-Jacob, B; Ehrmann, S; Rozec, B; Boulain, T

    2017-03-01

    During fluid challenge, volume expansion (VE)-induced increase in cardiac output (Δ VE CO) is seldom measured. In patients with shock undergoing strictly controlled mechanical ventilation and receiving VE, we assessed minimally invasive surrogates for Δ VE CO (by transthoracic echocardiography): fluid-induced increases in end-tidal carbon dioxide (Δ VE E'CO2 ); pulse (Δ VE PP), systolic (Δ VE SBP), and mean systemic blood pressure (Δ VE MBP); and femoral artery Doppler flow (Δ VE FemFlow). In the absence of arrhythmia, fluid-induced decrease in heart rate (Δ VE HR) and in pulse pressure respiratory variation (Δ VE PPV) were also evaluated. Areas under the receiver operating characteristic curves (AUC ROC s) reflect the ability to identify a response to VE (Δ VE CO ≥15%). In 86 patients, Δ VE E'CO2 had an AUC ROC =0.82 [interquartile range 0.73-0.90], significantly higher than the AUC ROC for Δ VE PP, Δ VE SBP, Δ VE MBP, and Δ VE FemFlow (AUC ROC =0.61-0.65, all P  value of Δ VE E'CO2  >1 mm Hg (>0.13 kPa) had good positive (5.0 [2.6-9.8]) and fair negative (0.29 [0.2-0.5]) likelihood ratios. The 16 patients with arrhythmia had similar relationships between Δ VE E'CO2 and Δ VE CO to patients with regular rhythm ( r 2 =0.23 in both subgroups). In 60 patients with no arrhythmia, Δ VE E'CO2 (AUC ROC =0.84 [0.72-0.92]) outperformed Δ VE HR (AUC ROC =0.52 [0.39-0.66], P value of Δ VE E'CO2 >1 mm Hg (>0.13 kPa) indicated a likely response to VE. © The Author 2017. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  14. Reduced heart rate and cardiac output differentially affect angiogenesis, growth, and development in early chicken embryos (Gallus domesticus).

    Science.gov (United States)

    Branum, Sylvia R; Yamada-Fisher, Miho; Burggren, Warren

    2013-01-01

    An increase in both vascular circumferential tension and shear stress in the developing vasculature of the chicken embryo has been hypothesized to stimulate angiogenesis in the developing peripheral circulation chorioallantoic membrane (CAM). To test this hypothesis, angiogenesis in the CAM, development, and growth were measured in the early chicken embryo, following acute and chronic topical application of the purely bradycardic drug ZD7288. At hour 56, ZD7288 reduced heart rate (f(H)) by ~30% but had no significant effect on stroke volume (~0.19 ± 0.2 μL), collectively resulting in a significant fall in cardiac output (CO) from ~27 ± 3 to 18 ± 2 μL min(-1). Mean f(H) at 72 h of development was similarly significantly lowered by acute ZD7288 treatment (250 μM) to 128 ± 0.3 beats min(-1), compared with 174.5 ± 0.3 and 174.7 ± 0.8 beats min(-1) in control and Pannett-Compton (P-C) saline-treated embryos, respectively. Chronic dosing with ZD7288-and the attendant decreases in f(H) and CO-did not change eye diameter or cervical flexion (key indicators of development rate) at 120 h but significantly reduced overall growth (wet and dry body mass decreased by 20%). CAM vessel density index (reflecting angiogenesis) measured 200-400 μm from the umbilical stalk was not altered, but ZD7288 reduced vessel numbers-and therefore vessel density-by 13%-16% more distally (500-600 μm from umbilical stalk) in the CAM. In the ZD7288-treated embryos, a decrease in vessel length was found within the second branch order (~300-400 μm from the umbilical stock), while a decrease in vessel diameter was found closer to the umbilical stock, beginning in the first branch order (~200-300 μm). Paradoxically, chronic application of P-C saline also reduced peripheral CAM vessel density index at 500 and 600 μm by 13% and 7%, respectively, likely from washout of local angiogenic factors. In summary, decreased f(H) with reduced CO did not slow development rate but reduced embryonic

  15. Noninvasive cardiac output monitoring during exercise testing: Nexfin pulse contour analysis compared to an inert gas rebreathing method and respired gas analysis.

    Science.gov (United States)

    Bartels, Sebastiaan A; Stok, Wim J; Bezemer, Rick; Boksem, Remco J; van Goudoever, Jeroen; Cherpanath, Thomas G V; van Lieshout, Johannes J; Westerhof, Berend E; Karemaker, John M; Ince, Can

    2011-10-01

    Exercise testing is often used to assess cardiac function during physical exertion to obtain diagnostic information. However, this procedure is limited to measuring the electrical activity of the heart using electrocardiography and intermittent blood pressure (BP) measurements and does not involve the continuous assessment of heart functioning. In this study, we compared continuous beat-to-beat pulse contour analysis to monitor noninvasive cardiac output (CO) during exercise with inert gas rebreathing and respired gas analysis. Nineteen healthy male volunteers were subjected to bicycle ergometry testing with increasing workloads. Cardiac output was deter- mined noninvasively by continuous beat-to-beat pulse contour analysis (Nexfin) and by inert gas rebreathing, and estimated using the respired gas analysis method. The effects of the rebreathing maneuver on heart rate (HR), stroke volume (SV), and CO were evaluated. The CO values derived from the Nexfin- and inert gas rebreathing methods were well correlated (r = 0.88, P measurement bias of 0.4 ± 1.8 L/min. Nexfin- and respired gas analysis-derived CO values correlated even better (r = 0.94, P measurement bias of -0.70 ± 1.6 L/min. At rest, the rebreathing maneuver increased HR by 13 beats/min (P parameters during exercise. Nexfin continuous beat-to-beat pulse contour analysis is an appropriate method for noninvasive assessment of CO during exercise.

  16. Effects of reduced rebreathing time, in spontaneously breathing patients, on respiratory effort and accuracy in cardiac output measurement when using a partial carbon dioxide rebreathing technique: a prospective observational study

    OpenAIRE

    Tachibana, Kazuya; Imanaka, Hideaki; Takeuchi, Muneyuki; Nishida, Tomoyo; Takauchi, Yuji; Nishimura, Masaji

    2005-01-01

    Introduction New technology using partial carbon dioxide rebreathing has been developed to measure cardiac output. Because rebreathing increases respiratory effort, we investigated whether a newly developed system with 35 s rebreathing causes a lesser increase in respiratory effort under partial ventilatory support than does the conventional system with 50 s rebreathing. We also investigated whether the shorter rebreathing period affects the accuracy of cardiac output measurement. Method Once...

  17. Comparing the accuracy of ES-BC, EIS-GS, and ES Oxi on body composition, autonomic nervous system activity, and cardiac output to standardized assessments

    Directory of Open Access Journals (Sweden)

    Lewis JE

    2011-09-01

    Full Text Available John E Lewis1, Stacey L Tannenbaum1, Jinrun Gao3, Angelica B Melillo1, Evan G Long1, Yaima Alonso2, Janet Konefal1, Judi M Woolger2, Susanna Leonard1, Prabjot K Singh1, Lawrence Chen1, Eduard Tiozzo1 1Department of Psychiatry and Behavioral Sciences, 2Department of Medicine, University of Miami Miller School of Medicine, Miami, FL, 3State Farm Insurance, Bloomington, IL, USA Background and purpose: The Electro Sensor Complex (ESC is software that combines three devices using bioelectrical impedance, galvanic skin response, and spectrophotometry: (1 ES-BC (Electro Sensor-Body Composition; LD Technology, Miami, FL to assess body composition, (2 EIS-GS (Electro Interstitial Scan-Galvanic Skin; LD Technology to predict autonomic nervous system activity, and (3 ES Oxi (Electro Sensor Oxi; LD Technology to assess cardiac output. The objective of this study was to compare each to a standardized assessment: ES-BC to dual-energy X-ray absorptiometry (DXA, EIS-GS to heart rate variability, and ES Oxi to BioZ Dx Diagnostic System (BioZ Dx; SonoSite Inc, Bothell, WA. Patients and methods: The study was conducted in two waves. Fifty subjects were assessed for body composition and autonomic nervous system activity. Fifty-one subjects were assessed for cardiac output. Results: We found adequate relative and absolute agreement between ES-BC and DXA for fat mass (r = 0.97, P < 0.001 with ES-BC overestimating fat mass by 0.1 kg and for body fat percentage (r = 0.92, P < 0.001 with overestimation of fat percentage by 0.4%. For autonomic nervous system activity, we found marginal relative agreement between EIS-GS and heart rate variability by using EIS-GS as the predictor in a linear regression equation (adjusted R2 = 0.56, P = 0.03. For cardiac output, adequate relative and absolute agreement was found between ES Oxi and BioZ Dx at baseline (r = 0.60, P < 0.001, after the first exercise stage (r = 0.79, P < 0.001, and after the second exercise stage (r = 0.86, P

  18. Effect of Levosimendan on Low Cardiac Output Syndrome in Patients With Low Ejection Fraction Undergoing Coronary Artery Bypass Grafting With Cardiopulmonary Bypass: The LICORN Randomized Clinical Trial.

    Science.gov (United States)

    Cholley, Bernard; Caruba, Thibaut; Grosjean, Sandrine; Amour, Julien; Ouattara, Alexandre; Villacorta, Judith; Miguet, Bertrand; Guinet, Patrick; Lévy, François; Squara, Pierre; Aït Hamou, Nora; Carillion, Aude; Boyer, Julie; Boughenou, Marie-Fazia; Rosier, Sebastien; Robin, Emmanuel; Radutoiu, Mihail; Durand, Michel; Guidon, Catherine; Desebbe, Olivier; Charles-Nelson, Anaïs; Menasché, Philippe; Rozec, Bertrand; Girard, Claude; Fellahi, Jean-Luc; Pirracchio, Romain; Chatellier, Gilles

    2017-08-08

    Low cardiac output syndrome after cardiac surgery is associated with high morbidity and mortality in patients with impaired left ventricular function. To assess the ability of preoperative levosimendan to prevent postoperative low cardiac output syndrome. Randomized, double-blind, placebo-controlled trial conducted in 13 French cardiac surgical centers. Patients with a left ventricular ejection fraction less than or equal to 40% and scheduled for isolated or combined coronary artery bypass grafting with cardiopulmonary bypass were enrolled from June 2013 until May 2015 and followed during 6 months (last follow-up, November 30, 2015). Patients were assigned to a 24-hour infusion of levosimendan 0.1 µg/kg/min (n = 167) or placebo (n = 168) initiated after anesthetic induction. Composite end point reflecting low cardiac output syndrome with need for a catecholamine infusion 48 hours after study drug initiation, need for a left ventricular mechanical assist device or failure to wean from it at 96 hours after study drug initiation when the device was inserted preoperatively, or need for renal replacement therapy at any time postoperatively. It was hypothesized that levosimendan would reduce the incidence of this composite end point by 15% in comparison with placebo. Among 336 randomized patients (mean age, 68 years; 16% women), 333 completed the trial. The primary end point occurred in 87 patients (52%) in the levosimendan group and 101 patients (61%) in the placebo group (absolute risk difference taking into account center effect, -7% [95% CI, -17% to 3%]; P = .15). Predefined subgroup analyses found no interaction with ejection fraction less than 30%, type of surgery, and preoperative use of β-blockers, intra-aortic balloon pump, or catecholamines. The prevalence of hypotension (57% vs 48%), atrial fibrillation (50% vs 40%), and other adverse events did not significantly differ between levosimendan and placebo. Among patients with low ejection fraction

  19. Effect of Levosimendan on Low Cardiac Output Syndrome in Patients With Low Ejection Fraction Undergoing Coronary Artery Bypass Grafting With Cardiopulmonary Bypass

    Science.gov (United States)

    Caruba, Thibaut; Grosjean, Sandrine; Amour, Julien; Ouattara, Alexandre; Villacorta, Judith; Miguet, Bertrand; Guinet, Patrick; Lévy, François; Squara, Pierre; Aït Hamou, Nora; Carillon, Aude; Boyer, Julie; Boughenou, Marie-Fazia; Rosier, Sebastien; Robin, Emmanuel; Radutoiu, Mihail; Durand, Michel; Guidon, Catherine; Desebbe, Olivier; Charles-Nelson, Anaïs; Menasché, Philippe; Rozec, Bertrand; Girard, Claude; Fellahi, Jean-Luc; Pirracchio, Romain; Chatellier, Gilles

    2017-01-01

    Importance Low cardiac output syndrome after cardiac surgery is associated with high morbidity and mortality in patients with impaired left ventricular function. Objective To assess the ability of preoperative levosimendan to prevent postoperative low cardiac output syndrome. Design, Setting, and Participants Randomized, double-blind, placebo-controlled trial conducted in 13 French cardiac surgical centers. Patients with a left ventricular ejection fraction less than or equal to 40% and scheduled for isolated or combined coronary artery bypass grafting with cardiopulmonary bypass were enrolled from June 2013 until May 2015 and followed during 6 months (last follow-up, November 30, 2015). Interventions Patients were assigned to a 24-hour infusion of levosimendan 0.1 µg/kg/min (n = 167) or placebo (n = 168) initiated after anesthetic induction. Main Outcomes and Measures Composite end point reflecting low cardiac output syndrome with need for a catecholamine infusion 48 hours after study drug initiation, need for a left ventricular mechanical assist device or failure to wean from it at 96 hours after study drug initiation when the device was inserted preoperatively, or need for renal replacement therapy at any time postoperatively. It was hypothesized that levosimendan would reduce the incidence of this composite end point by 15% in comparison with placebo. Results Among 336 randomized patients (mean age, 68 years; 16% women), 333 completed the trial. The primary end point occurred in 87 patients (52%) in the levosimendan group and 101 patients (61%) in the placebo group (absolute risk difference taking into account center effect, −7% [95% CI, −17% to 3%]; P = .15). Predefined subgroup analyses found no interaction with ejection fraction less than 30%, type of surgery, and preoperative use of β-blockers, intra-aortic balloon pump, or catecholamines. The prevalence of hypotension (57% vs 48%), atrial fibrillation (50% vs 40%), and other adverse

  20. The properties of batrachotoxin-modified cardiac Na channels, including state-dependent block by tetrodotoxin.

    Science.gov (United States)

    Huang, L Y; Yatani, A; Brown, A M

    1987-09-01

    Batrachotoxin (BTX) modification and tetrodotoxin (TTX) block of BTX-modified Na channels were studied in single cardiac cells of neonatal rats using the whole-cell patch-clamp recording technique. The properties of BTX-modified Na channels in heart are qualitatively similar to those in nerve. However, quantitative differences do exist between the modified channels of these two tissues. In the heart, the shift of the conductance-voltage curve for the modified channel was less pronounced, the maximal activation rate constant, (tau m)max, of modified channels was considerably slower, and the slow inactivation of the BTX-modified cardiac Na channels was only partially abolished. TTX blocked BTX-modified mammalian cardiac Na channels and the block decreased over the potential range of -80 to -40 mV. The apparent dissociation constant of TTX changed from 0.23 microM at -50 mV to 0.69 microM at 0 mV. No further reduction of block was observed at potentials greater than -40 mV. This is the potential range over which gating from closed to open states occurred. These results were explained by assuming that TTX has a higher affinity for closed BTX-modified channels than for open modified channels. Hence, the TTX-binding rate constants are considered to be state dependent rather than voltage dependent. This differs from the voltage dependence of TTX block reported for BTX-modified Na channels from membrane vesicles incorporated into lipid bilayers and from amphibian node of Ranvier.

  1. Intention, Principle, Outputs and Aims of the Experimental Pavilion Research of Building Envelopes Including Windows for Wooden Buildings

    Science.gov (United States)

    Štaffenová, Daniela; Rybárik, Ján; Jakubčík, Miroslav

    2017-06-01

    The aim of experimental research in the area of exterior walls and windows suitable for wooden buildings was to build special pavilion laboratories. These laboratories are ideally isolated from the surrounding environment, airtight and controlled by the constant internal climate. The principle of experimental research is measuring and recording of required physical parameters (e.g. temperature or relative humidity). This is done in layers of experimental fragment sections in the direction from exterior to interior, as well as in critical places by stable interior and real exterior climatic conditions. The outputs are evaluations of experimental structures behaviour during the specified time period, possibly during the whole year by stable interior and real exterior boundary conditions. The main aim of this experimental research is processing of long-term measurements of experimental structures and the subsequent analysis. The next part of the research consists of collecting measurements obtained with assistance of the experimental detached weather station, analysis, evaluation for later setting up of reference data set for the research locality, from the point of view of its comparison to the data sets from Slovak Hydrometeorological Institute (SHMU) and to localities with similar climate conditions. Later on, the data sets could lead to recommendations for design of wooden buildings.

  2. Effects of reduced rebreathing time, in spontaneously breathing patients, on respiratory effort and accuracy in cardiac output measurement when using a partial carbon dioxide rebreathing technique: a prospective observational study.

    Science.gov (United States)

    Tachibana, Kazuya; Imanaka, Hideaki; Takeuchi, Muneyuki; Nishida, Tomoyo; Takauchi, Yuji; Nishimura, Masaji

    2005-10-05

    New technology using partial carbon dioxide rebreathing has been developed to measure cardiac output. Because rebreathing increases respiratory effort, we investigated whether a newly developed system with 35 s rebreathing causes a lesser increase in respiratory effort under partial ventilatory support than does the conventional system with 50 s rebreathing. We also investigated whether the shorter rebreathing period affects the accuracy of cardiac output measurement. Once a total of 13 consecutive post-cardiac-surgery patients had recovered spontaneous breathing under pressure support ventilation, we applied a partial carbon dioxide rebreathing technique with rebreathing of 35 s and 50 s in a random order. We measured minute ventilation, and arterial and mixed venous carbon dioxide tension at the end of the normal breathing period and at the end of the rebreathing periods. We then measured cardiac output using the partial carbon dioxide rebreathing technique with the two rebreathing periods and using thermodilution. With both rebreathing systems, minute ventilation increased during rebreathing, as did arterial and mixed venous carbon dioxide tensions. The increases in minute ventilation and arterial carbon dioxide tension were less with 35 s rebreathing than with 50 s rebreathing. The cardiac output measures with both systems correlated acceptably with values obtained with thermodilution. When patients breathe spontaneously the partial carbon dioxide rebreathing technique increases minute ventilation and arterial carbon dioxide tension, but the effect is less with a shorter rebreathing period. The 35 s rebreathing period yielded cardiac output measurements similar in accuracy to those with 50 s rebreathing.

  3. Total bile acid levels are associated with left atrial volume and cardiac output in patients with cirrhosis

    DEFF Research Database (Denmark)

    Voiosu, Andrei M; Wiese, Signe; Voiosu, Theodor A

    2018-01-01

    , echocardiographic, and biochemical means. Associations between total serum BA concentrations and markers of systolic or diastolic dysfunction and the presence of cirrhotic cardiomyopathy were tested through univariate and multivariate analyses. RESULTS: Fifty-eight patients with cirrhosis were assessed...... and diastolic dysfunction were rare in the cohort. Total BA levels associated with several echocardiographic parameters of the hyperdynamic syndrome in univariate analysis but only with left atrial volume in multivariate analysis (P=0.007). BA concentrations did not differ according to the presence...... to investigate the association between total BA levels and echocardiographic and biochemical markers of cardiac dysfunction in cirrhotic patients. METHODS: Cirrhotic patients were enrolled prospectively in this hypothesis-generating study and evaluated for cardiac and hemodynamic dysfunction through clinical...

  4. Low cardiac output as physiological phenomenon in hibernating, free-ranging Scandinavian brown bears (Ursus arctos) - an observational study

    DEFF Research Database (Denmark)

    Jørgensen, Peter Godsk; Arnemo, Jon; Swenson, Jon E

    2014-01-01

    BACKGROUND: Despite 5-7 months of physical inactivity during hibernation, brown bears (Ursus arctos) are able to cope with physiological conditions that would be detrimental to humans. During hibernation, the tissue metabolic demands fall to 25% of the active state. Our objective was to assess...... cardiac function associated with metabolic depression in the hibernating vs. active states in free-ranging Scandinavian brown bears. METHODS: We performed echocardiography on seven free-ranging brown bears in Dalarna, Sweden, anesthetized with medetomidine-zolazepam-tiletamine-ketamine during winter.......31) l/min vs. 3.54 (SD: 1.04) l/min (P=0.003), and mean cardiac index 0.63 (SD: 0.21) l/min/kg vs. 2.45 (SD: 0.52) l/min/ m2 (Pbears during hibernation, despite the absence of atrial arrhythmias and valvular disease...

  5. GASTO CARDÍACO MATERNO COMO PREDICTOR DEL SÍNDROME DE PREECLAMPSIA-ECLAMPSIA / Maternal cardiac output as a predictor of preeclampsia-eclampsia syndrome

    Directory of Open Access Journals (Sweden)

    Luis A. Díaz Moreno

    2012-03-01

    Full Text Available Resumen Introducción y objetivos: La hipertensión es la complicación médica más común del embarazo, y puede dejar secuelas permanentes como: alteraciones neurológicas, hepáticas, hematológicas o renales. Cada tres minutos muere una mujer debido a la preeclampsia. Durante el embarazo el gasto cardíaco sufre un incremento de hasta 40 %. Este incremento es secundario al aumento de aproximadamente 30 % del volumen sistólico. El objetivo de la investigación fue predecir la aparición del síndrome de preeclampsia-eclampsia mediante la identificación de alteraciones del gasto cardíaco. Método: Se realizó un estudio observacional, descriptivo, longitudinal y analítico, de cohorte prospectiva, donde se determinó, por ecocardiografía, el gasto cardíaco en 31 embarazadas, entre las semanas 11 y 13,6 de gestación como único valor; y mediante seguimiento prenatal, se observó la aparición o no del síndrome de Preeclampsia-Eclampsia. Resultados: Se logró el seguimiento de 31 embarazadas a las que se le midió el gasto cardíaco, y se encontró una prevalecía de la enfermedad de 12,9 % con un 64,5 % de pacientes correctamente diagnosticados, con una sensibilidad de 75 %, con valor predictivo positivo de 23 %, especificidad de 62 % y valor predictivo negativo de 94%, con un riesgo relativo de 4,1 (intervalo de confianza 95 %, 0,48-35,6. Conclusiones: Es posible establecer la medición de gasto cardíaco como estudio de escrutinio para predecir la aparición del síndrome de Preeclampsia desde el control prenatal, y contribuir así a la disminución de la muerte materna. / Abstract Introduction and Objectives: Hypertension is the most common medical complication of pregnancy, and it can leave permanent sequelae such as neurological, hepatic, hematological or renal disorders. Every three minutes a woman dies due to preeclampsia. During pregnancy, cardiac output suffers an increase of 40%. This increase is secondary to an increase of

  6. External cardiac compression may be harmful in some scenarios of pulseless electrical activity.

    LENUS (Irish Health Repository)

    Hogan, T S

    2012-10-01

    Pulseless electrical activity occurs when organised or semi-organised electrical activity of the heart persists but the product of systemic vascular resistance and the increase in systemic arterial flow generated by the ejection of the left venticular stroke volume is not sufficient to produce a clinically detectable pulse. Pulseless electrical activity encompasses a very heterogeneous variety of severe circulatory shock states ranging in severity from pseudo-cardiac arrest to effective cardiac arrest. Outcomes of cardiopulmonary resuscitation for pulseless electrical activity are generally poor. Impairment of cardiac filling is the limiting factor to cardiac output in many scenarios of pulseless electrical activity, including extreme vasodilatory shock states. There is no evidence that external cardiac compression can increase cardiac output when impaired cardiac filling is the limiting factor to cardiac output. If impaired cardiac filling is the limiting factor to cardiac output and the heart is effectively ejecting all the blood returning to it, then external cardiac compression can only increase cardiac output if it increases venous return and cardiac filling. Repeated cardiac compression asynchronous with the patient\\'s cardiac cycle and raised mean intrathoracic pressure due to chest compression can be expected to reduce rather than to increase cardiac filling and therefore to reduce rather than to increase cardiac output in such circumstances. The hypothesis is proposed that the performance of external cardiac compression will have zero or negative effect on cardiac output in pulseless electrical activity when impaired cardiac filling is the limiting factor to cardiac output. External cardiac compression may be both directly and indirectly harmful to significant sub-groups of patients with pulseless electrical activity. We have neither evidence nor theory to provide comfort that external cardiac compression is not harmful in many scenarios of pulseless

  7. External cardiac compression may be harmful in some scenarios of pulseless electrical activity.

    Science.gov (United States)

    Hogan, T S

    2012-10-01

    Pulseless electrical activity occurs when organised or semi-organised electrical activity of the heart persists but the product of systemic vascular resistance and the increase in systemic arterial flow generated by the ejection of the left venticular stroke volume is not sufficient to produce a clinically detectable pulse. Pulseless electrical activity encompasses a very heterogeneous variety of severe circulatory shock states ranging in severity from pseudo-cardiac arrest to effective cardiac arrest. Outcomes of cardiopulmonary resuscitation for pulseless electrical activity are generally poor. Impairment of cardiac filling is the limiting factor to cardiac output in many scenarios of pulseless electrical activity, including extreme vasodilatory shock states. There is no evidence that external cardiac compression can increase cardiac output when impaired cardiac filling is the limiting factor to cardiac output. If impaired cardiac filling is the limiting factor to cardiac output and the heart is effectively ejecting all the blood returning to it, then external cardiac compression can only increase cardiac output if it increases venous return and cardiac filling. Repeated cardiac compression asynchronous with the patient's cardiac cycle and raised mean intrathoracic pressure due to chest compression can be expected to reduce rather than to increase cardiac filling and therefore to reduce rather than to increase cardiac output in such circumstances. The hypothesis is proposed that the performance of external cardiac compression will have zero or negative effect on cardiac output in pulseless electrical activity when impaired cardiac filling is the limiting factor to cardiac output. External cardiac compression may be both directly and indirectly harmful to significant sub-groups of patients with pulseless electrical activity. We have neither evidence nor theory to provide comfort that external cardiac compression is not harmful in many scenarios of pulseless

  8. Fluid Balance, Change in Serum Creatinine and Urine Output as Markers of Acute Kidney Injury Post Cardiac Surgery: An Observational Study

    Directory of Open Access Journals (Sweden)

    Katrina Chau

    2014-08-01

    Full Text Available Background: Acute kidney injury (AKI is defined as oliguria or rise in serum creatinine but oliguria alone as a diagnostic criterion may over-diagnose AKI. Objectives: Given the association between fluid overload and AKI, we aimed to determine if positive fluid balance can complement the known parameters in assessing outcomes of AKI. Design: Prospective observational study. Setting: Teaching hospital in Vancouver, Canada. Patients: 111 consecutive patients undergoing elective cardiac surgery from January to April 2012. Measurements: Outcomes of cardiac surgery intensive care unit (CSICU and hospital length of stay (LOS in relation to fluid balance, urine output and serum creatinine. Methods: All fluid input and output was recorded for 72 hours post-operatively. Positive fluid balance was defined as >6.5 cc/kg. Daily serum creatinine and hourly urine output were recorded and patients were defined as having AKI according to the AKIN criteria. Results: Of the patients who were oliguric, those with fluid overload trended towards longer LOS than those without fluid overload [CSICU LOS: 62 and 39 hours (unadjusted p-value 0.02, adjusted p-value 0.58; hospital LOS: 13 and 9 days (unadjusted p-value: 0.05, adjusted p-value: 0.16]. Patients with oliguria who were fluid overloaded had similar LOS to patients with overt AKI (change in serum creatinine ≥ 26.5 μmol/L, [CSICU LOS: 62 and 69 hours (adjusted p value: 0.32 and hospital LOS: 13 and 14 days (adjusted p value: 0.19]. Patients with oliguria regardless of fluid balance had longer CSICU LOS (adjusted p value: 0.001 and patients who were fluid overloaded in the absence of AKI had longer hospital LOS (adjusted p value: 0.02. Limitations: Single centre, small sample, LOS as outcome. Conclusions: Oliguria and positive fluid balance is associated with a trend towards longer LOS as compared to oliguria alone. Fluid balance may therefore be a useful marker of AKI, in addition to urine output and serum

  9. Monitoring of cardiac output and lung ventilation by Electrical Impedance Tomography in a porcine model of acute lung injury.

    Science.gov (United States)

    Hochhausen, Nadine; Dohmeier, Henriette; Rossaint, Rolf; Czaplik, Michael

    2017-07-01

    Adequate medical treatment of the Acute Respiratory Distress Syndrome is still challenging since patient-individual aspects have to be taken into account. Lung protective ventilation and hemodynamic stability have always been two of the most crucial aims of intensive care therapy. For both aspects, a continuous - preferably non-invasive - monitoring is desirable that is available at the bedside. Unfortunately, there is no technique clinically established yet, that provides both measurement of cardiac stroke volume and ventilation dynamics in real-time. Electrical Impedance Tomography (EIT) is a promising technique to close this gap. The aim of the study was to investigate if stroke volume can be estimated by a self-developed software using EIT-based image analysis. In addition, two EIT-derived parameters, namely Global Inhomogeneity Index (GII) and Impedance Ratio (IR), were calculated to evaluate homogeneity of air distribution. Experimental acute lung injury (ALI) was provoked in seven female pigs (German Landrace) by lipopolysaccharide (LPS). All animals suffered from experimental ALI 3 to 4 hours after LPS infusion. At defined time points, respiratory and hemodynamic parameters, blood gas analyses and EIT-recordings were performed. Eight hours after ALI, animals were euthanized. Stroke volume, derived from pulmonary artery catheter (PAC), decreased continuously up to four hours after ALI. Then, stroke volume increased slightly. Stroke volume, derived from the self-developed tool, showed the same characteristics (p=0.047, r = 0.365). In addition to the GII and IR individually, both classified scores showed a high correlation with the Horowitz Index, defined as p a O 2 /FiO 2 . To conclude, EIT-derived measures enabled a reliable estimation of cardiac stroke volume and regional distribution of ventilation.

  10. Content validation of the operational definitions of the nursing diagnoses of activity intolerance, excess fluid volume, and decreased cardiac output in patients with heart failure.

    Science.gov (United States)

    de Souza, Vanessa; Zeitoun, Sandra Salloum; Lopes, Camila Takao; de Oliveira, Ana Paula Dias; Lopes, Juliana de Lima; de Barros, Alba Lucia Botura Leite

    2014-06-01

    To consensually validate the operational definitions of the nursing diagnoses activity intolerance, excessive fluid volume, and decreased cardiac output in patients with decompensated heart failure. Consensual validation was performed in two stages: analogy by similarity of defining characteristics, and development of operational definitions and validation with experts. A total of 38 defining characteristics were found. Operational definitions were developed and content-validated. One hundred percent of agreement was achieved among the seven experts after five rounds. "Ascites" was added in the nursing diagnosis excessive fluid volume. The consensual validation improves interpretation of human response, grounding the selection of nursing interventions and contributing to improved nursing outcomes. Support the assessment of patients with decompensated heart failure. © 2013 NANDA International.

  11. Accuracy and precision of the ultrasound cardiac output monitor (USCOM 1A) in pregnancy: comparison with three-dimensional transthoracic echocardiography.

    Science.gov (United States)

    McNamara, H; Barclay, P; Sharma, V

    2014-10-01

    Cardiac output (CO) monitoring is helpful in the assessment of critically ill pregnant women, but invasive monitors are often unsuitable for use. We aimed to measure agreement between the non-invasive ultrasound cardiac output monitor (USCOM) and three-dimensional transthoracic echocardiography (3D-TTE) in pregnant women. Healthy pregnant women from 25 weeks gestation onwards participated. In the left lateral position at rest, CO was measured with the USCOM and 3D-TTE. A single operator performed all USCOM measurements, with a different operator performing all echocardiography. Both were blinded to results from the other device. Each USCOM trace was analysed using two modes: flowtrace (FT) and touchpoint (TP). A second, blinded USCOM reading was taken to assess reproducibility. USCOM readings were obtained in 92, and 3D-TTE images in 85 participants. The mean CO was 5.7, 7.7, and 6.2 litre min(-1) measured by 3D-TTE, USCOM FT, and USCOM TP, respectively. USCOM bias was +2.0 litre min(-1) (FT) and +0.4 litre min(-1) (TP). Limits of agreement were -0.2 to +4.2 litre min(-1) (FT) and -1.4 to +2.3 litre min(-1) (TP). The mean percentage difference was 32.6% (FT) and 31.4% (TP) for CO and 27.0% (FT) and 27.5% (TP) for stroke volume. Intraclass correlation between repeated USCOM readings was 0.9 (FT) and 0.86 (TP). USCOM has acceptable agreement with 3D-TTE for the measurement of CO in pregnancy. The positive bias of the USCOM, particularly in the FT mode, may be due to the hyperdynamic cardiovascular state in pregnancy. We suggest using the TP mode in this patient population. © The Author 2014. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Non-invasive in vivo measurement of cardiac output in C57BL/6 mice using high frequency transthoracic ultrasound: evaluation of gender and body weight effects.

    Science.gov (United States)

    Domínguez, Elisabet; Ruberte, Jesús; Ríos, José; Novellas, Rosa; Del Alamo, Maria Montserrat Rivera; Navarro, Marc; Espada, Yvonne

    2014-10-01

    Even though mice are being increasingly used as models for human cardiovascular diseases, non-invasive monitoring of cardiovascular parameters such as cardiac output (CO) in this species is challenging. In most cases, the effects of gender and body weight (BW) on these parameters have not been studied. The objective of this study was to provide normal reference values for CO in C57BL/6 mice, and to describe possible gender and/or BW associated differences between them. We used 30-MHz transthoracic Doppler ultrasound to measure hemodynamic parameters in the ascending aorta [heart rate (HR), stroke volume (SV), stroke index (SI), CO, and cardiac index (CI)] in ten anesthetized mice of either sex. No differences were found for HR, SV, and CO. Both SI and CI were statistically lower in males. However, after normalization for BW, these differences disappeared. These results suggest that if comparisons of cardiovascular parameters are to be made between male and female mice, values should be standardized for BW.

  13. Uncomplicated human type 2 diabetes is associated with meal-induced blood pressure lowering and cardiac output increase.

    Science.gov (United States)

    Smits, Mark M; Muskiet, Marcel H A; Tushuizen, Maarten E; Kwa, Kelly A A; Karemaker, John M; van Raalte, Daniël H; Diamant, Michaela

    2014-12-01

    Since many type 2 diabetes patients experience postprandial hypotension, the aim of this study was to unravel meal-related changes in systemic hemodynamics and autonomic nervous system (ANS)-balance. Forty-two age-matched males (15 type 2 diabetes; 12 metabolic syndrome; 15 controls) without overt autonomic neuropathy received a standardized high-fat mixed meal after an overnight fast. Hemodynamic variables were measured by finger plethysmography. Fourier analysis was used to calculate the low-/high-frequency (LF/HF)-ratio, a marker of autonomic nervous system-balance, and baroreceptor reflex sensitivity (BRS). Following the meal, diastolic blood pressure (DBP) decreased in type 2 diabetes patients only, paralleled by a significant decrement in systemic vascular resistance (SVR) and an increase in cardiac index. All groups showed an increase in postprandial heart rate. Controls, but not metabolic syndrome or type 2 diabetes patients, showed a meal-related increase in LF/HF-ratio. When combining all study subjects, homeostatic model assessment-insulin resistance (HOMA-IR) was inversely correlated with changes in DBP, SVR, LF/HF-ratio and BRS. Based on these data, we hypothesize that in patients with uncomplicated type 2 diabetes, insulin resistance hampers adequate meal-induced sympathetic activation, leading to a decrease in SVR and resulting in a postprandial drop in DBP. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. Validation of maternal cardiac output assessed by transthoracic echocardiography against pulmonary artery catheterization in severely ill pregnant women: prospective comparative study and systematic review.

    Science.gov (United States)

    Cornette, J; Laker, S; Jeffery, B; Lombaard, H; Alberts, A; Rizopoulos, D; Roos-Hesselink, J W; Pattinson, R C

    2017-01-01

    Most severe pregnancy complications are characterized by profound hemodynamic disturbances, thus there is a need for validated hemodynamic monitoring systems for pregnant women. Pulmonary artery catheterization (PAC) using thermodilution is the clinical gold standard for the measurement of cardiac output (CO), however this reference method is rarely performed owing to its invasive nature. Transthoracic echocardiography (TTE) allows non-invasive determination of CO. We aimed to validate TTE against PAC for the determination of CO in severely ill pregnant women. This study consisted of a meta-analysis combining data from a prospective study and a systematic review. The prospective arm was conducted in Pretoria, South Africa, in 2003. Women with severe pregnancy complications requiring invasive monitoring with PAC according to contemporary guidelines were included. TTE was performed within 15 min of PAC and the investigator was blinded to the PAC measurements. Comparative measurements were extracted from similar studies retrieved from a systematic review of the literature and added to a database. Simultaneous CO measurements by TTE and PAC were compared. Agreement between methods was assessed using Bland-Altman statistics and intraclass correlation coefficients (ICC). Thirty-four comparative measurements were included in the meta-analysis. Mean CO values obtained by PAC and TTE were 7.39 L/min and 7.18 L/min, respectively. The bias was 0.21 L/min with lower and upper limits of agreement of -1.18 L/min and 1.60 L/min, percentage error was 19.1%, and ICC between the two methods was 0.94. CO measurements by TTE show excellent agreement with those obtained by PAC in pregnant women. Given its non-invasive nature and availability, TTE could be considered as a reference for the validation of other CO techniques in pregnant women. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Las complicaciones del embarazo más graves se caracterizan por trastornos hemodin

  15. [Pulse indicator continuous cardiac output measurement-guided treatment aids two pediatric patients with severe acute pancreatitis complicated with acute respiratory distress syndrome].

    Science.gov (United States)

    Yan, Weiyuan; Wang, Lijie

    2014-09-01

    To evaluate the clinical value of the pulse indicator continuous cardiac output (PiCCO) system in patients with severe acute pancreatitis (SAP) complicated with acute respiratory distress syndrome (ARDS). Two cases of SAP with ARDS were monitored using PiCCO during comprehensive management in the Pediatric Intensive Care Unit (PICU) of Shengjing Hospital, China Medical University. To guide fluid management, the cardiac index (CI) was measured to assess cardiac function, the global end-diastolic volume index (GEDVI) was used to evaluate cardiac preload, and the extravascular lung water index (EVLWI) was used to evaluate the pulmonary edema. Case 1 was diagnosed with type L2 acute lymphoblastic leukemia (intermediate risk) and received the sixth maintenance phases of chemotherapy this time. After a 1-week dosage of chemotherapeutic drugs (pegaspargase and mitoxantrone), he suffered SAP combined with ARDS. Except comprehensive treatment (life supporting, antibiotic, etc.) and applying continuous veno-venous hemodiafiltration (CVVHDF) to remove inflammatory mediators. PiCCO monitor was utilized to guide fluid management. During the early stage of PiCCO monitoring, the patient showed no significant manifestations of pulmonary edema in the bedside chest X-ray (bedside ultrasound showed left pleural effusion), and had an oxygenation index 223 mmHg (1 mmHg = 0.133 kPa), GEDVI 450 ml/m², and ELVWI 7 ml/kg. We increased cardiac output to increase tissue perfusion and dehydration speed of CVVHDF was set at 70 ml/h. Two hours later, GEDVI significantly increased to 600 ml/m² and ELVWI significantly increased to 10 ml/kg, the oxygenation index declined to 155 mmHg, the bedside chest X-ray showed a significant decrease of permeability (right lung) and PEEP was adjusted to 5 cmH₂O (1 cmH₂O = 0.098 kPa), indicating circulating overload. ARDS subsequently occurred, upon which the fluid infusion was halted, the dehydration rate of CVVHDF raised (adjusted to 100-200 ml/h). On

  16. Body Image and quality of life of senior citizens included in a cardiac rehabilitation program

    Directory of Open Access Journals (Sweden)

    Fernanda Vargas Amaral

    2013-12-01

    Full Text Available Most people who have to live with some kind of disease tend to adopt healthy habits and create new ways of seeing themselves. The aim of this study is to explore the relationship between the index of quality of life and self perception of patients included in a cardiovascular rehabilitation program in Florianopolis/Brazil. The sample consists of 24 subjects of 62 ± 1.3 years of age, who have coronary artery disease. The Minnesota Living With Heart Failure Questionnaire (MLHFQ was used to assess the quality of life, and to identify the degree of body image discontentment the Stunkard and Sorensen questionnaire (1993 was applied. Statistical analysis was made through statistics programs and the software SPSS 11.0. The degree of association between variables was studied with Kendall test. It was verified that the higher the BMI and the current body shape, the greatest the degree of body image dissatisfaction. The emotional symptoms also appear to be significantly correlated with a desire for a smaller body shape and with indicators of lower quality of life (r = 0474 = 0735, p major 0.05. The physical symptoms were also considerably associated with the emotional symptoms. These results suggest that the variables concerning the quality of life are meaningful to significant body image and satisfaction, which seems to correlate with fewer emotional problems and better facing of the disease. Cardiovascular Rehabilitation Programs that implement physical activity in daily habits proves to be a suitable tool for improving these ailments in this post-acute phase

  17. Improving risk assessment for post-surgical low cardiac output syndrome in patients without severely reduced ejection fraction undergoing open aortic valve replacement. The role of global longitudinal strain and right ventricular free wall strain

    NARCIS (Netherlands)

    Balderas-Munoz, K.; Rodriguez-Zanella, H.; Fritche-Salazar, J. F.; Avila-Vanzzini, N.; Juarez Orozco, L. E.; Arias-Godinez, J. A.; Calvillo-Arguelles, O.; Rivera-Peralta, S.; Sauza-Sosa, J. C.; Ruiz-Esparza, M. E.; Bucio-Reta, E.; Rmero, A.; Espinola-Zavaleta, N.; Dominguez-Mendez, B.; Gaxiola-Macias, M.; Martinez-Rios, M. A.

    2017-01-01

    Low cardiac output syndrome (LCOS) after surgical aortic valve replacement (SAVR) is related to increased mortality and treatment related costs. We aimed to evaluate whether echocardiography-derived left ventricular global longitudinal strain (LV-GLS) relates to the occurrence of postoperative LCOS

  18. Comparison of stroke volume and cardiac output as measured by a single observer using four different ultrasound techniques in six clinically healthy cats.

    Science.gov (United States)

    Biermann, K; Hungerbühler, S; Kästner, S B R

    2012-12-01

    The aim of this study was to assess agreement and repeatability of four ultrasound methods for measuring stroke volume (SV) and cardiac output (CO) in cats. Measurement of SV and CO was performed by the Teichholz method, the Simpson's method (SM), the area length method (ALM) and a volumetric flow method across the aorta (Trace method). For each method, the coefficient of variation (CV) was calculated and agreement was determined by Bland-Altman analysis. The CV was acceptable (parameters, except for SV and CO obtained by SM (28.8% and 22.4%, respectively) and ALM (21.6% and 22.6%, respectively). Narrow limits of agreement were observed between both planimetric methods (SM and ALM). The Trace method was the most repeatable, followed by the Teichholz method. Despite excellent inter-method agreement, neither of the planimetric methods produced results with adequate repeatability. As the Teichholz and Trace methods were acceptably repeatable, and probably gave the most representative values, they appear to be the most useful methods for the measurement of SV and CO in cats. Further investigations are needed to compare the echocardiographic methods described here with a standard technique such as thermodilution. Copyright © 2012. Published by Elsevier Ltd.

  19. Phosphodiesterase inhibitor KMUP-3 displays cardioprotection via protein kinase G and increases cardiac output via G-protein-coupled receptor agonist activity and Ca2+ sensitization

    Directory of Open Access Journals (Sweden)

    Chung-Pin Liu

    2016-02-01

    Full Text Available KMUP-3 (7-{2-[4-(4-nitrobenzene piperazinyl]ethyl}-1, 3-dimethylxanthine displays cardioprotection and increases cardiac output, and is suggested to increase cardiac performance and improve myocardial infarction. To determine whether KMUP-3 improves outcomes in hypoperfused myocardium by inducing Ca2+ sensitization to oppose protein kinase (PKG-mediated Ca2+ blockade, we measured left ventricular systolic blood pressure, maximal rates of pressure development, mean arterial pressure and heart rate in rats, and measured contractility and expression of PKs/RhoA/Rho kinase (ROCKII in beating guinea pig left atria. Hemodynamic changes induced by KMUP-3 (0.5–3.0 mg/kg, intravenously were inhibited by Y27632 [(R-(+-trans-4-1-aminoethyl-N-(4-Pyridyl cyclohexane carboxamide] and ketanserin (1 mg/kg, intravenously. In electrically stimulated left guinea pig atria, positive inotropy induced by KMUP-3 (0.1–100μM was inhibited by the endothelial NO synthase (eNOS inhibitors N-nitro-l-arginine methyl ester (L-NAME and 7-nitroindazole, cyclic AMP antagonist SQ22536 [9-(terahydro-2-furanyl-9H-purin-6-amine], soluble guanylyl cyclase (sGC antagonist ODQ (1H-[1,2,4] oxadiazolo[4,3-a] quinoxalin-1-one, RhoA inhibitor C3 exoenzyme, β-blocker propranolol, 5-hydroxytryptamine 2A antagonist ketanserin, ROCK inhibitor Y27632 and KMUP-1 (7-{2-[4-(2-chlorobenzene piperazinyl]ethyl}-1, 3-dimethylxanthine at 10μM. Western blotting assays indicated that KMUP-3 (0.1–10μM increased PKA, RhoA/ROCKII, and PKC translocation and CIP-17 (an endogenous 17-kDa inhibitory protein activation. In spontaneous right atria, KMUP-3 induced negative chronotropy that was blunted by 7-nitroindazole and atropine. In neonatal myocytes, L-NAME inhibited KMUP-3-induced eNOS phosphorylation and RhoA/ROCK activation. In H9c2 cells, Y-27632 (50μM and PKG antagonist KT5823 [2,3,9,10,11,12-hexahydro-10R- methoxy-2,9-dimethyl-1-oxo-9S,12R-epoxy-1H-diindolo(1,2,3-fg:3′,2′,1

  20. Semi-quantitative metabolic values on FDG PET/CT including extracardiac sites of disease as a predictor of treatment course in patients with cardiac sarcoidosis.

    Science.gov (United States)

    Ishiyama, Mitsutomi; Soine, Laurie A; Vesselle, Hubert J

    2017-08-18

    Cardiac sarcoidosis is associated with major adverse cardiac events including cardiac arrest, for which anti-inflammatory treatment is indicated. Oral corticosteroid is the mainstay among treatment options; however, adverse effects are a major concern with long-term use. It would be beneficial for providers to predict treatment response and prognosis for proper management strategy of sarcoidosis, though it remains challenging. Fluorine (F)-18 fluorodeoxyglucose (FDG)-positron emission tomography(PET)/computed tomography(CT) has an advantage over anatomical imaging in providing semi-quantitative functional parameters such as standard uptake value (SUV), metabolic volume, and total lesion glycolysis (TLG), which are well-established biomarkers in oncology. However, the relationship between these parameters and treatment response has not been fully investigated in cardiac sarcoidosis. Also, the prognostic value of extracardiac active inflammation noted on FDG-PET/CT in the setting of cardiac sarcoidosis is unclear. The aim of this retrospective study was to investigate the prognostic value of semi-quantitative values of both cardiac and extracardiac disease sites derived from FDG-PET/CT in predicting treatment course in cardiac sarcoidosis. Sixteen consecutive patients with suspected cardiac sarcoidosis, who demonstrated abnormal myocardial activity on cardiac-inflammation FDG-PET/CT encompassing the entire chest/upper abdomen and subsequently underwent corticosteroid therapy for diagnosis of active cardiac sarcoidosis, were included. Semi-quantitative values of hypermetabolic lesions were derived from all visualized organ system and were compared to daily corticosteroid dose at 6 months.  Of the 16 patients, 81.3% (13/16) of the patients showed extracardiac involvement. The lesion with the greatest SUV was identified in the heart in 11 patients (68.7%), in the liver in 1 patient (6.3%), and in lymph nodes in 4 patients (25%). The maximum SUV across all visualized

  1. The first missense mutation of NHS gene in a Tunisian family with clinical features of NHS syndrome including cardiac anomaly.

    Science.gov (United States)

    Chograni, Manèl; Rejeb, Imen; Jemaa, Lamia Ben; Châabouni, Myriam; Bouhamed, Habiba Chaabouni

    2011-08-01

    Nance-Horan Syndrome (NHS) or X-linked cataract-dental syndrome is a disease of unknown gene action mechanism, characterized by congenital cataract, dental anomalies, dysmorphic features and, in some cases, mental retardation. We performed linkage analysis in a Tunisian family with NHS in which affected males and obligate carrier female share a common haplotype in the Xp22.32-p11.21 region that contains the NHS gene. Direct sequencing of NHS coding exons and flanking intronic sequences allowed us to identify the first missense mutation (P551S) and a reported SNP-polymorphism (L1319F) in exon 6, a reported UTR-SNP (c.7422 C>T) and a novel one (c.8239 T>A) in exon 8. Both variations P551S and c.8239 T>A segregate with NHS phenotype in this family. Although truncations, frame-shift and copy number variants have been reported in this gene, no missense mutations have been found to segregate previously. This is the first report of a missense NHS mutation causing NHS phenotype (including cardiac defects). We hypothesize also that the non-reported UTR-SNP of the exon 8 (3'-UTR) is specific to the Tunisian population.

  2. A prospective comparison of a noninvasive cardiac output monitor versus esophageal Doppler monitor for goal-directed fluid therapy in colorectal surgery patients.

    Science.gov (United States)

    Waldron, Nathan H; Miller, Timothy E; Thacker, Julie K; Manchester, Amy K; White, William D; Nardiello, John; Elgasim, Magdi A; Moon, Richard E; Gan, Tong J

    2014-05-01

    Goal-directed fluid therapy (GDFT) is associated with improved outcomes after surgery. The esophageal Doppler monitor (EDM) is widely used, but has several limitations. The NICOM, a completely noninvasive cardiac output monitor (Cheetah Medical), may be appropriate for guiding GDFT. No prospective studies have compared the NICOM and the EDM. We hypothesized that the NICOM is not significantly different from the EDM for monitoring during GDFT. One hundred adult patients undergoing elective colorectal surgery participated in this study. Patients in phase I (n = 50) had intraoperative GDFT guided by the EDM while the NICOM was connected, and patients in phase II (n = 50) had intraoperative GDFT guided by the NICOM while the EDM was connected. Each patient's stroke volume was optimized using 250-mL colloid boluses. Agreement between the monitors was assessed, and patient outcomes (postoperative pain, nausea, and return of bowel function), complications (renal, pulmonary, infectious, and wound complications), and length of hospital stay (LOS) were compared. Using a 10% increase in stroke volume after fluid challenge, agreement between monitors was 60% at 5 minutes, 61% at 10 minutes, and 66% at 15 minutes, with no significant systematic disagreement (McNemar P > 0.05) at any time point. The EDM had significantly more missing data than the NICOM. No clinically significant differences were found in total LOS or other outcomes. The mean LOS was 6.56 ± 4.32 days in phase I and 6.07 ± 2.85 days in phase II, and 95% confidence limits for the difference were -0.96 to +1.95 days (P = 0.5016). The NICOM performs similarly to the EDM in guiding GDFT, with no clinically significant differences in outcomes, and offers increased ease of use as well as fewer missing data points. The NICOM may be a viable alternative monitor to guide GDFT.

  3. A comparison of volume clamp method-based continuous noninvasive cardiac output (CNCO) measurement versus intermittent pulmonary artery thermodilution in postoperative cardiothoracic surgery patients.

    Science.gov (United States)

    Wagner, Julia Y; Körner, Annmarie; Schulte-Uentrop, Leonie; Kubik, Mathias; Reichenspurner, Hermann; Kluge, Stefan; Reuter, Daniel A; Saugel, Bernd

    2018-04-01

    The CNAP technology (CNSystems Medizintechnik AG, Graz, Austria) allows continuous noninvasive arterial pressure waveform recording based on the volume clamp method and estimation of cardiac output (CO) by pulse contour analysis. We compared CNAP-derived CO measurements (CNCO) with intermittent invasive CO measurements (pulmonary artery catheter; PAC-CO) in postoperative cardiothoracic surgery patients. In 51 intensive care unit patients after cardiothoracic surgery, we measured PAC-CO (criterion standard) and CNCO at three different time points. We conducted two separate comparative analyses: (1) CNCO auto-calibrated to biometric patient data (CNCO bio ) versus PAC-CO and (2) CNCO calibrated to the first simultaneously measured PAC-CO value (CNCO cal ) versus PAC-CO. The agreement between the two methods was statistically assessed by Bland-Altman analysis and the percentage error. In a subgroup of patients, a passive leg raising maneuver was performed for clinical indications and we present the changes in PAC-CO and CNCO in four-quadrant plots (exclusion zone 0.5 L/min) in order to evaluate the trending ability of CNCO. The mean difference between CNCO bio and PAC-CO was +0.5 L/min (standard deviation ± 1.3 L/min; 95% limits of agreement -1.9 to +3.0 L/min). The percentage error was 49%. The concordance rate was 100%. For CNCOcal, the mean difference was -0.3 L/min (±0.5 L/min; -1.2 to +0.7 L/min) with a percentage error of 19%. In this clinical study in cardiothoracic surgery patients, CNCO cal showed good agreement when compared with PAC-CO. For CNCO bio , we observed a higher percentage error and good trending ability (concordance rate 100%).

  4. No psychological distress in sportsmen aged 45 years and older after cardiovascular screening, including cardiac CT : The Measuring Athlete's Risk of Cardiovascular events (MARC) study

    NARCIS (Netherlands)

    Schurink, M. M.; Braber, T. L.; Prakken, N. H. J.; Doevendans, P. A. F. M.; Backx, F. J. G.; Grobbee, D. E.; Rienks, R.; Nathoe, H. M.; Bots, M. L.; Velthuis, B. K.; Mosterd, A.

    Background Psychological distress caused by cardiovascular pre-participation screening (PPS) may be a reason not to implement a PPS program. We assessed the psychological impact of PPS, including cardiac computed tomography (CT), in 318 asymptomatic sportsmen aged >= 45 years. Methods Coronary

  5. No psychological distress in sportsmen aged 45 years and older after cardiovascular screening, including cardiac CT : The Measuring Athlete’s Risk of Cardiovascular events (MARC) study

    NARCIS (Netherlands)

    Schurink, M. M.; Braber, T. L.; Prakken, N. H J; Doevendans, P. A F M; Backx, F. J G; Grobbee, D. E.; Rienks, R.; Nathoe, H. M.; Bots, M. L.; Velthuis, B. K.; Mosterd, A.

    2017-01-01

    Background Psychological distress caused by cardiovascular pre-participation screening (PPS) may be a reason not to implement a PPS program. We assessed the psychological impact of PPS, including cardiac computed tomography (CT), in 318 asymptomatic sportsmen aged ≥45 years. Methods Coronary artery

  6. Cardiovascular Ultrasound of Neonatal Long Evans Rats Exposed Prenatally to Trichloroacetic Acid: Effects on Heart Rate, Ejection Fraction, and Cardiac Output

    Science.gov (United States)

    This abstract describes the use of a relatively new technology, cardiovascular ultrasound (echocardiography) for evaluating developmental toxicity affecting heart development. The abstract describes the effects of two known cardiac teratogens, trichloroacetic acid and dimethadio...

  7. Use of a Minimally Invasive Cardiac Output Monitor to Optimise Haemodynamics in a Patient with Mitral Valve Disease Undergoing Cerebrovascular Surgery

    Directory of Open Access Journals (Sweden)

    Ali M. Al-Mashani

    2017-08-01

    Full Text Available Patients with mitral valve disease undergoing cerebrovascular surgery face increased inherent risks due to their associated cardiac comorbidities. As such, the anaesthetic management of such patients is distinctly challenging. Simultaneous consideration of both the cerebrovascular and underlying cardiac conditions determines key anaesthetic issues, as fluids and vasopressors or inotropes need to be titrated according to haemodynamic variables in order to optimise cerebral blood flow without compromising cardiac function. We report a 45-yearold female patient with mild mitral stenosis and moderate-to-severe mitral regurgitation who presented to the Khoula Hospital, Muscat, Oman, in 2016 following a ruptured anterior communicating artery aneurysm requiring urgent surgical intervention. As highlighted in this case, the VolumeView EV1000™ (Edwards Lifesciences, Irvine, California, USA system is a minimially invasive haemodynamic monitor that can help immensely in the perioperative management of such patients.

  8. Unit 16 - Output

    OpenAIRE

    Unit 16, CC in GIS; Star, Jeffrey L.

    1990-01-01

    This unit discusses issues related to GIS output, including the different types of output possible and the hardware for producing each. It describes text, graphic and digital data that can be generated by a GIS as well as line printers, dot matrix printers/plotters, pen plotters, optical scanners and cathode ray tubes (CRTs) as technologies for generating the output.

  9. Aortic and Hepatic Contrast Enhancement During Hepatic-Arterial and Portal Venous Phase Computed Tomography Scanning: Multivariate Linear Regression Analysis Using Age, Sex, Total Body Weight, Height, and Cardiac Output.

    Science.gov (United States)

    Masuda, Takanori; Nakaura, Takeshi; Funama, Yoshinori; Higaki, Toru; Kiguchi, Masao; Imada, Naoyuki; Sato, Tomoyasu; Awai, Kazuo

    We evaluated the effect of the age, sex, total body weight (TBW), height (HT) and cardiac output (CO) of patients on aortic and hepatic contrast enhancement during hepatic-arterial phase (HAP) and portal venous phase (PVP) computed tomography (CT) scanning. This prospective study received institutional review board approval; prior informed consent to participate was obtained from all 168 patients. All were examined using our routine protocol; the contrast material was 600 mg/kg iodine. Cardiac output was measured with a portable electrical velocimeter within 5 minutes of starting the CT scan. We calculated contrast enhancement (per gram of iodine: [INCREMENT]HU/gI) of the abdominal aorta during the HAP and of the liver parenchyma during the PVP. We performed univariate and multivariate linear regression analysis between all patient characteristics and the [INCREMENT]HU/gI of aortic- and liver parenchymal enhancement. Univariate linear regression analysis demonstrated statistically significant correlations between the [INCREMENT]HU/gI and the age, sex, TBW, HT, and CO (all P linear regression analysis showed that only the TBW and CO were of independent predictive value (P linear regression analysis only the TBW and CO were significantly correlated with aortic and liver parenchymal enhancement; the age, sex, and HT were not. The CO was the only independent factor affecting aortic and liver parenchymal enhancement at hepatic CT when the protocol was adjusted for the TBW.

  10. Three-dimensional display and measurement of cardiac dynamic indexes from MR images

    International Nuclear Information System (INIS)

    Kono, M.; Matsuo, M.; Yamasaki, K.; Banno, T.; Toriwaki, J.; Yokoi, S.; Oshita, H.

    1986-01-01

    The cardiac dynamic index, to which such variables as cardiac output, ejection fraction, and wall motion contribute, is routinely determined using various modalities such as angiography, radionuclide imaging, US, and x-ray CT. Each of these modalities, however, has some disadvantages in regard to evaluating the cardiac dynamic index. The authors have obtained precise multidirectional projection images of the heart by means of computer graphics and reformatted data of cardiac MR images obtained with cardiac gating. The contiguous coronal MR images of the heart are made at an interimage distance of 5 mm. In each section, five or six cardiac images can be obtained, depending on the systolic or diastolic phase. These images are stored in a computer, and a three-dimensional display of the heart with biocular observation and with multiplex holograms is made possible with computer graphics. Three-dimensional measurement of the cardiac index is now being attempted, including cardiac output, ejection fraction, and wall motion

  11. Impact of a Multidisciplinary Team Approach Including an Intensivist on the Outcomes of Critically Ill Patients in the Cardiac Care Unit.

    Science.gov (United States)

    Fanari, Zaher; Barekatain, Armin; Kerzner, Roger; Hammami, Sumaya; Weintraub, William S; Maheshwari, Vinay

    2016-12-01

    To investigate the impact of integrating a medical intensivist into a cardiac care unit (CCU) multidisciplinary team on the outcomes of CCU patients. We conducted a retrospective cohort study of 2239 CCU admissions between July 1, 2011, and July 1, 2013, which constituted patients admitted in the 12 months before and 12 months after the introduction of intensivists into the CCU multidisciplinary team. This team included a cardiologist, a medical intensivist, medical house staff, nurses, a pharmacist, a dietitian, and physical and respiratory therapists. The primary outcome was CCU mortality. Secondary outcomes included hospital mortality, CCU length of stay, hospital length of stay, and duration of mechanical ventilation. After the implementation of a multidisciplinary team approach, there was a significant decrease in both adjusted CCU mortality (3.5% vs 5.9%; P=.01) and hospital mortality (4.4% vs 11.1%; Pmultidisciplinary team approach in which an intensivist and a cardiologist comanage the critical care of CCU patients is feasible and may result in better patient outcomes. Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  12. Acebutolol in Cardiac Arrhythmias

    African Journals Online (AJOL)

    1974-04-20

    Apr 20, 1974 ... the cardiac output at rest and on exercise is not altered by the administration of acebutolol, and in patients with coronary artery disease, intravenous acebutolol produces a small fall in cardiac index, stroke index and in the parameters which are used to measure left ventricular. contractilityYo. We have used ...

  13. [Experimental Approach to Analysis of the Relationship between Food Environments and Lifestyle-Related Diseases, Including Cardiac Hypertrophy, Fatty Liver, and Fatigue Symptoms].

    Science.gov (United States)

    Horiuchi, Masahisa; Nakakuma, Miwa; Arimura, Emi; Ushikai, Miharu; Yoshida, Goichiro

    2015-01-01

    The food habit is involved in the onset and development of lifestyle-related diseases. In this review I would like to describe a historical case of vitamin B1 deficiency, as well as our case study of fatty acid metabolism abnormality due to carnitine deficiency. In history, the army and navy personnel in Japan at the end of the 19th century received food rations based on a high-carbohydrate diet including white rice, resulting in the onset of beriberi. An epidemiological study by Kenkan Takaki revealed the relationship between the onset of beriberi and rice intake. Then, Takaki was successful in preventing the onset of beriberi by changing the diet. However, the primary cause had yet to be elucidated. Finally, Christian Eijkman established an animal model of beriberi (chickens) showing peripheral neuropathy, and he identified the existence of an anti-beriberi substance, vitamin B1. This is an example of the successful control of a disease by integrating the results of epidemiological and experimental studies. In our study using a murine model of fatty acid metabolism abnormality caused by carnitine deficiency, cardiac abnormality and fatty liver developed depending on the amount of dietary fat. In addition, the mice showed disturbance of orexin neuron activity related to the sleep-arousal system, which is involved in fatigue symptoms under fasting condition, one of the states showing enhanced fatty acid metabolism. These findings suggest that fatty acid toxicity is enhanced when the mice are more dependent on fatty acid metabolism. Almost simultaneously, a human epidemiological study showed that narcolepsy, which is caused by orexin system abnormality, is associated with the polymorphism of the gene coding for carnitine palmitoyltransferase 1B, which is involved in carnitine metabolism. To understand the pathological mechanism of fatty acid toxicity, not only an experimental approach using animal models, but also an epidemiological approach is necessary. The

  14. Blood pressure and heart rate from the arterial blood pressure waveform can reliably estimate cardiac output in a conscious sheep model of multiple hemorrhages and resuscitation using computer machine learning approaches.

    Science.gov (United States)

    Liu, Nehemiah T; Kramer, George C; Khan, Muzna N; Kinsky, Michael P; Salinas, José

    2015-10-01

    This study was a first step to facilitate the development of automated decision support systems using cardiac output (CO) for combat casualty care. Such systems remain a practical challenge in battlefield and prehospital settings. In these environments, reliable CO estimation using blood pressure (BP) and heart rate (HR) may provide additional capabilities for diagnosis and treatment of trauma patients. The aim of this study was to demonstrate that continuous BP and HR from the arterial BP waveform coupled with machine learning (ML) can reliably estimate CO in a conscious sheep model of multiple hemorrhages and resuscitation. Hemodynamic parameters (BPs, HR) were derived from 100-Hz arterial BP waveforms of 10 sheep records, 3 hours to 4 hours long. Two models (mean arterial pressure, Windkessel) were then applied and merged to estimate COVS. ML was used to develop a rule for identifying when models required calibration. All records contained 100-Hz recording of pulmonary arterial blood flow using Doppler transit time (COFP). COFP and COVS were analyzed using equivalence tests and Bland-Altman analysis, as well as waveform and concordance plots. Baseline COFP varied from 3.0 L/min to 5.4 L/min, while posthemorrhage COFP varied from 1.0 L/min to 1.8 L/min. A total of 315,196 pairs of data were obtained. Equivalence tests for individual records showed that COVS was statistically equivalent to COFP (p < 0.05). Smaller equivalence thresholds (<0.3 L/min) indicated an overall high COFP accuracy. The agreement between COFP and COVS was -0.13 (0.69) L/min (Bland-Altman). In an exclusion zone of 12%, trending analysis found a 92% concordance between 5-minute changes in COFP and COVS. This study showed that CO can be reliably estimated using BPs and HR from the arterial BP waveform in combination with ML. A next step will be to test this approach using noninvasive BPs and HR.

  15. Update to the study protocol, including statistical analysis plan for a randomized clinical trial comparing comprehensive cardiac rehabilitation after heart valve surgery with control

    DEFF Research Database (Denmark)

    Sibilitz, Kirstine Laerum; Berg, Selina Kikkenborg; Hansen, Tina Birgitte

    2015-01-01

    , either valve replacement or repair, remains the treatment of choice. However, post-surgery, the transition to daily living may become a physical, mental and social challenge. We hypothesize that a comprehensive cardiac rehabilitation program can improve physical capacity and self-assessed mental health...

  16. Changes in cardiac physiology after severe burn injury.

    Science.gov (United States)

    Williams, Felicia N; Herndon, David N; Suman, Oscar E; Lee, Jong O; Norbury, William B; Branski, Ludwik K; Mlcak, Ronald P; Jeschke, Marc G

    2011-01-01

    Cardiac stress, mediated by increased catecholamines, is the hallmark of severe burn injury typified by marked tachycardia, increased myocardial oxygen consumption, and increased cardiac output (CO). It remains one of the main determinants of survival in large burns. Currently, it is unknown for how long cardiac stress persists after a severe injury. Therefore, the aim of this study was to determine the extent and duration of cardiac stress after a severe burn. To determine persistence of cardiac alteration, the authors determined cardiac parameters of all surviving patients with burns ≥ 40% TBSA from 1998 to 2008. One hundred ninety-four patients were included in this study. Heart rate, mean arterial pressure, CO, stroke volume, cardiac index, and ejection fractions were measured at regular intervals from admission up to 2 years after injury. Rate pressure product was calculated as a correlate of myocardial oxygen consumption. All values were compared with normal nonburned children to validate the findings. Statistical analysis was performed using log transformed analysis of variance with Bonferroni correction and Student's t-test, where applicable. Heart rate, CO, cardiac index, and rate pressure product remained significantly increased in burned children for up to 2 years when compared with normal ranges (P < .05), indicating vastly increased cardiac stress. Ejection fraction was within normal limits for 2 years. Cardiac stress persists for at least 2 years postburn, and the authors suggest that attenuation of these detrimental responses may improve long-term morbidity.

  17. Dynamic NMR cardiac imaging in a piglet

    Energy Technology Data Exchange (ETDEWEB)

    Doyle, M.; Rzedzian, R.; Mansfield, P. (Nottingham Univ. (UK). Dept. of Physics); Coupland, R.E. (Nottingham Univ. (UK). Queen' s Medical Centre)

    1983-12-01

    NMR echo-planar imaging (EPI) has been used in a real-time mode to visualise the thorax of a live piglet. Moving pictures are available on an immediate image display system which demonstrates dynamic cardiac function. Frame rates vary from one per cardiac cycle in a prospective stroboscopic mode with immediate visual output to a maximum of 10 frames per second yielding up to six looks in one piglet heart cycle, but using a visual playback mode. A completely new system has been used to obtain these images, features of which include a probe assembly with 22 cm access and an AP400 array processor for real-time data processing.

  18. Inverter communications using output signal

    Science.gov (United States)

    Chapman, Patrick L.

    2017-02-07

    Technologies for communicating information from an inverter configured for the conversion of direct current (DC) power generated from an alternative source to alternating current (AC) power are disclosed. The technologies include determining information to be transmitted from the inverter over a power line cable connected to the inverter and controlling the operation of an output converter of the inverter as a function of the information to be transmitted to cause the output converter to generate an output waveform having the information modulated thereon.

  19. Anaesthetic management of a rare variety of cardiac myxoma for ...

    African Journals Online (AJOL)

    Primary cardiac tumours are rare. Right ventricular myxomas and a combination of right atrial and ventricular myxomas are very rare. A patient with myxoma has several problems, including haemodynamic compromise in a particular position, embolisation and hypoxaemia because of low output and possible shunts.

  20. Cardiac Pacemakers

    International Nuclear Information System (INIS)

    Fiandra, O.; Espasandin, W.; Fiandra, H.

    1984-01-01

    A complete survey of physiological biophysical,clinical and engineering aspects of cardiac facing,including the history and an assessment of possible future developments.Among the topics studied are: pacemakers, energy search, heart stimulating with pacemakers ,mathematical aspects of the electric cardio stimulation chronic, pacemaker implants,proceeding,treatment and control

  1. Physiologic stress interventions in cardiac imaging

    International Nuclear Information System (INIS)

    Buda, A.J.

    1985-01-01

    Physiologic stress interventions are designed to assess the reserve capability of coronary flow and myocardial function. In the normal individual, a sufficiently intense physiologic stress may increase coronary flow and cardiac output by 500% to 600%. However, in patients with cardiac disease, these reserve responses may be absent, or considerably blunted. Thus, physiologic stress testing has proved extremely helpful in detecting cardiac abnormalities when resting cardiac function appears normal. Although dynamic exercise remains the standard approach to physiologic stress testing, a number of other interventions have been used, including: (1) isometric exercise, (2) atrial pacing, (3) cold pressor testing, (4) postextrasystolic potentiation, (5) volume loading, and (6) negative intrathoracic pressure. Each of these may be considered an alternative physiologic intervention whenever dynamic exercise is not feasible. These alternative approaches are important since, in our experience, 20% to 30% of subjects are unable to perform dynamic exercise, or exercise inadequately to produce a sufficiently intense cardiac stress. This chapter reviews physiologic considerations, indications, contraindications, protocols, and results of these physiologic stress interventions when used in combination with cardiac radionuclide procedures

  2. The incidence of rugby-related catastrophic injuries (including cardiac events) in South Africa from 2008 to 2011: a cohort study.

    Science.gov (United States)

    Brown, James Craig; Lambert, Mike I; Verhagen, Evert; Readhead, Clint; van Mechelen, Willem; Viljoen, Wayne

    2013-01-01

    To establish an accurate and comprehensive injury incidence registry of all rugby union-related catastrophic events in South Africa between 2008 and 2011. An additional aim was to investigate correlates associated with these injuries. Prospective. The South African amateur and professional rugby-playing population. An estimated 529 483 Junior and 121 663 Senior rugby union ('rugby') players (population at risk). Annual average incidences of rugby-related catastrophic injuries by type (cardiac events, traumatic brain and acute spinal cord injuries (ASCIs)) and outcome (full recoveries-fatalities). Playing level (junior and senior levels), position and event (phase of play) were also assessed. The average annual incidence of ASCIs and Traumatic Brain Injuries combined was 2.00 per 100 000 players (95% CI 0.91 to 3.08) from 2008 to 2011. The incidence of ASCIs with permanent outcomes was significantly higher at the Senior level (4.52 per 100 000 players, 95% CI 0.74 to 8.30) than the Junior level (0.24 per 100 000 players, 95% CI 0 to 0.65) during this period. The hooker position was associated with 46% (n=12 of 26) of all permanent ASCI outcomes, the majority of which (83%) occurred during the scrum phase of play. The incidence of rugby-related catastrophic injuries in South Africa between 2008 and 2011 is comparable to that of other countries and to most other collision sports. The higher incidence rate of permanent ASCIs at the Senior level could be related to the different law variations or characteristics (eg, less regular training) compared with the Junior level. The hooker and scrum were associated with high proportions of permanent ASCIs. The BokSmart injury prevention programme should focus efforts on these areas (Senior level, hooker and scrum) and use this study as a reference point for the evaluation of the effectiveness of the programme.

  3. Cardiac function and long-term volume load : Physiological investigations in endurance athletes and in patients operated on for aortic regurgitation

    OpenAIRE

    Hedman, Kristofer

    2016-01-01

    Background and aims. The heart is a remarkably adaptable organ, continuously changing its output to match metabolic demands and haemodynamic load. But also in long-term settings, such as in chronic or repeated volume load, there are changes in cardiac dimensions and mass termed cardiac hypertrophy. Depending on the stimulus imposing the volume load this hypertrophy differs in extent and phenotype. We aimed to study cardiac function in two settings with long-term volume load, including patient...

  4. Regulation of Cardiac Hypertrophy: the nuclear option

    NARCIS (Netherlands)

    D.W.D. Kuster (Diederik)

    2011-01-01

    textabstractCardiac hypertrophy is the response of the heart to an increased workload. After myocardial infarction (MI) the surviving muscle tissue has to work harder to maintain cardiac output. This sustained increase in workload leads to cardiac hypertrophy. Despite its apparent appropriateness,

  5. The incidence of rugby-related catastrophic injuries (including cardiac events) in South Africa from 2008 to 2011: a cohort study

    Science.gov (United States)

    Brown, James Craig; Lambert, Mike I; Verhagen, Evert; Readhead, Clint; van Mechelen, Willem; Viljoen, Wayne

    2013-01-01

    Objectives To establish an accurate and comprehensive injury incidence registry of all rugby union-related catastrophic events in South Africa between 2008 and 2011. An additional aim was to investigate correlates associated with these injuries. Design Prospective. Setting The South African amateur and professional rugby-playing population. Participants An estimated 529 483 Junior and 121 663 Senior rugby union (‘rugby’) players (population at risk). Outcome measures Annual average incidences of rugby-related catastrophic injuries by type (cardiac events, traumatic brain and acute spinal cord injuries (ASCIs)) and outcome (full recoveries—fatalities). Playing level (junior and senior levels), position and event (phase of play) were also assessed. Results The average annual incidence of ASCIs and Traumatic Brain Injuries combined was 2.00 per 100 000 players (95% CI 0.91 to 3.08) from 2008 to 2011. The incidence of ASCIs with permanent outcomes was significantly higher at the Senior level (4.52 per 100 000 players, 95% CI 0.74 to 8.30) than the Junior level (0.24 per 100 000 players, 95% CI 0 to 0.65) during this period. The hooker position was associated with 46% (n=12 of 26) of all permanent ASCI outcomes, the majority of which (83%) occurred during the scrum phase of play. Conclusions The incidence of rugby-related catastrophic injuries in South Africa between 2008 and 2011 is comparable to that of other countries and to most other collision sports. The higher incidence rate of permanent ASCIs at the Senior level could be related to the different law variations or characteristics (eg, less regular training) compared with the Junior level. The hooker and scrum were associated with high proportions of permanent ASCIs. The BokSmart injury prevention programme should focus efforts on these areas (Senior level, hooker and scrum) and use this study as a reference point for the evaluation of the effectiveness of the programme. PMID:23447464

  6. Prevalence of nursing diagnosis of decreased cardiac output and the predictive value of defining characteristics in patients under evaluation for heart transplant Prevalencia del diagnóstico de enfermería de disminución del gasto cardíaco y valor predictivo de las características definidoras en pacientes en fase de evaluación para trasplante cardíaco Prevalência do diagnóstico de enfermagem de débito cardíaco diminuído e valor preditivo das características definidoras em pacientes em avaliação para transplante cardíaco

    OpenAIRE

    Lígia Neres Matos; Tereza Cristina Felippe Guimarães; Marcos Antônio Gomes Brandão; Deyse Conceição Santoro

    2012-01-01

    The purposes of the study were to identify the prevalence of defining characteristics (DC) of decreased cardiac output (DCO) in patients with cardiac insufficiency under evaluation for heart transplantation, and to ascertain the likelihood of defining characteristics being predictive factors for the existence of reduction in cardiac output. Data was obtained by retrospective documental analysis of the clinical records of right-sided heart catheterizations in 38 patients between 2004 and 2009....

  7. De novo 14q24.2q24.3 microdeletion including IFT43 is associated with intellectual disability, skeletal anomalies, cardiac anomalies, and myopia.

    Science.gov (United States)

    Stokman, Marijn F; Oud, Machteld M; van Binsbergen, Ellen; Slaats, Gisela G; Nicolaou, Nayia; Renkema, Kirsten Y; Nijman, Isaac J; Roepman, Ronald; Giles, Rachel H; Arts, Heleen H; Knoers, Nine V A M; van Haelst, Mieke M

    2016-06-01

    We report an 11-year-old girl with mild intellectual disability, skeletal anomalies, congenital heart defect, myopia, and facial dysmorphisms including an extra incisor, cup-shaped ears, and a preauricular skin tag. Array comparative genomic hybridization analysis identified a de novo 4.5-Mb microdeletion on chromosome 14q24.2q24.3. The deleted region and phenotype partially overlap with previously reported patients. Here, we provide an overview of the literature on 14q24 microdeletions and further delineate the associated phenotype. We performed exome sequencing to examine other causes for the phenotype and queried genes present in the 14q24.2q24.3 microdeletion that are associated with recessive disease for variants in the non-deleted allele. The deleted region contains 65 protein-coding genes, including the ciliary gene IFT43. Although Sanger and exome sequencing did not identify variants in the second IFT43 allele or in other IFT complex A-protein-encoding genes, immunocytochemistry showed increased accumulation of IFT-B proteins at the ciliary tip in patient-derived fibroblasts compared to control cells, demonstrating defective retrograde ciliary transport. This could suggest a ciliary defect in the pathogenesis of this disorder. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  8. Treatment approach, delivery, and follow-up evaluation for cardiac rhythm disease management patients receiving radiation therapy: retrospective physician surveys including chart reviews at numerous centers.

    Science.gov (United States)

    Gossman, Michael S; Wilkinson, Jeffrey D; Mallick, Avishek

    2014-01-01

    In a 2-part study, we first examined the results of 71 surveyed physicians who provided responses on how they address the management of patients who maintained either a pacemaker or a defibrillator during radiation treatment. Second, a case review study is presented involving 112 medical records reviewed at 18 institutions to determine whether there was a change in the radiation prescription for the treatment of the target cancer, the method of radiation delivery, or the method of radiation image acquisition. Statistics are provided to illustrate the level of administrative policy; the level of communication between radiation oncologists and heart specialists; American Joint Committee on Cancer (AJCC) staging and classification; National Comprehensive Cancer Network (NCCN) guidelines; tumor site; patient׳s sex; patient׳s age; device type; manufacturer; live monitoring; and the reported decisions for planning, delivery, and imaging. This survey revealed that 37% of patient treatments were considered for some sort of change in this regard, whereas 59% of patients were treated without regard to these alternatives when available. Only 3% of all patients were identified with an observable change in the functionality of the device or patient status in comparison with 96% of patients with normal behavior and operating devices. Documented changes in the patient׳s medical record included 1 device exhibiting failure at 0.3-Gy dose, 1 device exhibiting increased sensor rate during dose delivery, 1 patient having an irregular heartbeat leading to device reprogramming, and 1 patient complained of twinging in the chest wall that resulted in a respiratory arrest. Although policies and procedures should directly involve the qualified medical physicist for technical supervision, their sufficient involvement was typically not requested by most respondents. No treatment options were denied to any patient based on AJCC staging, classification, or NCCN practice standards. Copyright

  9. Treatment approach, delivery, and follow-up evaluation for cardiac rhythm disease management patients receiving radiation therapy: Retrospective physician surveys including chart reviews at numerous centers

    Energy Technology Data Exchange (ETDEWEB)

    Gossman, Michael S., E-mail: MGossman@TSRCC.com [Regulation Directive Medical Physics, Russell, KY (United States); Wilkinson, Jeffrey D. [Medtronic, Inc., Mounds View, MN (United States); Mallick, Avishek [Department of Mathematics, Marshall University, Huntington, WV (United States)

    2014-01-01

    In a 2-part study, we first examined the results of 71 surveyed physicians who provided responses on how they address the management of patients who maintained either a pacemaker or a defibrillator during radiation treatment. Second, a case review study is presented involving 112 medical records reviewed at 18 institutions to determine whether there was a change in the radiation prescription for the treatment of the target cancer, the method of radiation delivery, or the method of radiation image acquisition. Statistics are provided to illustrate the level of administrative policy; the level of communication between radiation oncologists and heart specialists; American Joint Committee on Cancer (AJCC) staging and classification; National Comprehensive Cancer Network (NCCN) guidelines; tumor site; patient's sex; patient's age; device type; manufacturer; live monitoring; and the reported decisions for planning, delivery, and imaging. This survey revealed that 37% of patient treatments were considered for some sort of change in this regard, whereas 59% of patients were treated without regard to these alternatives when available. Only 3% of all patients were identified with an observable change in the functionality of the device or patient status in comparison with 96% of patients with normal behavior and operating devices. Documented changes in the patient's medical record included 1 device exhibiting failure at 0.3-Gy dose, 1 device exhibiting increased sensor rate during dose delivery, 1 patient having an irregular heartbeat leading to device reprogramming, and 1 patient complained of twinging in the chest wall that resulted in a respiratory arrest. Although policies and procedures should directly involve the qualified medical physicist for technical supervision, their sufficient involvement was typically not requested by most respondents. No treatment options were denied to any patient based on AJCC staging, classification, or NCCN practice standards.

  10. Input-output supervisor

    International Nuclear Information System (INIS)

    Dupuy, R.

    1970-01-01

    The input-output supervisor is the program which monitors the flow of informations between core storage and peripheral equipments of a computer. This work is composed of three parts: 1 - Study of a generalized input-output supervisor. With sample modifications it looks like most of input-output supervisors which are running now on computers. 2 - Application of this theory on a magnetic drum. 3 - Hardware requirement for time-sharing. (author) [fr

  11. Stimulating endogenous cardiac regeneration

    Directory of Open Access Journals (Sweden)

    Amanda eFinan

    2015-09-01

    Full Text Available The healthy adult heart has a low turnover of cardiac myocytes. The renewal capacity, however, is augmented after cardiac injury. Participants in cardiac regeneration include cardiac myocytes themselves, cardiac progenitor cells, and peripheral stem cells, particularly from the bone marrow compartment. Cardiac progenitor cells and bone marrow stem cells are augmented after cardiac injury, migrate to the myocardium, and support regeneration. Depletion studies of these populations have demonstrated their necessary role in cardiac repair. However, the potential of these cells to completely regenerate the heart is limited. Efforts are now being focused on ways to augment these natural pathways to improve cardiac healing, primarily after ischemic injury but in other cardiac pathologies as well. Cell and gene therapy or pharmacological interventions are proposed mechanisms. Cell therapy has demonstrated modest results and has passed into clinical trials. However, the beneficial effects of cell therapy have primarily been their ability to produce paracrine effects on the cardiac tissue and recruit endogenous stem cell populations as opposed to direct cardiac regeneration. Gene therapy efforts have focused on prolonging or reactivating natural signaling pathways. Positive results have been demonstrated to activate the endogenous stem cell populations and are currently being tested in clinical trials. A potential new avenue may be to refine pharmacological treatments that are currently in place in the clinic. Evidence is mounting that drugs such as statins or beta blockers may alter endogenous stem cell activity. Understanding the effects of these drugs on stem cell repair while keeping in mind their primary function may strike a balance in myocardial healing. To maximize endogenous cardiac regeneration,a combination of these approaches couldameliorate the overall repair process to incorporate the participation ofmultiple cell players.

  12. Validation of the concept Risk for Decreased Cardiac Output Validación del concepto riesgo de débito cardiaco disminuido Validação do conceito risco de débito cardíaco diminuído

    Directory of Open Access Journals (Sweden)

    Eduarda Ribeiro dos Santos

    2013-02-01

    Full Text Available OBJECTIVES: to validate the concept "risk for decreased cardiac output". METHOD: Six of the eight steps suggested in the technique developed by Walker & Avant were adopted to analyze the concept of the phenomenon under study and the proposal made by Hoskins was used for content validation, taking into account agreement achieved among five experts. RESULTS: the concept "decreased cardiac output" was found in the nursing and medical fields and refers to the heart's pumping capacity while the concept "risk" is found in a large number of disciplines. In regard to the defining attributes, "impaired pumping capacity" was the main attribute of decreased cardiac output and "probability" was the main attribute of risk. The uses and defining attributes of the concepts "decreased cardiac output" and "risk" were analyzed as well as their antecedent and consequent events in order to establish the definition of "risk for decreased cardiac output", which was validated by 100% of the experts. CONCLUSION: The obtained data indicate that the risk for decreased cardiac output phenomenon can be a nursing diagnosis and refining it can contribute to the advancement of nursing classifications in this context.OBJETIVO: Validar el concepto riesgo del débito cardíaco disminuido. MÉTODO: Fue adoptada la técnica de Walker & Avant para analizar la definición del fenómeno enfocado, utilizando seis de las ocho etapas sugeridas y la propuesta de Hoskins para validar el contenido, considerándose la conformidad entre cinco expertos. RESULTADOS: el concepto de debito cardíaco disminuido se encuentra en las áreas enfermería y médica y su atención se centra en la capacidad de bombeo del corazón. Sin embargo, el concepto de riesgo es presente en un gran número de áreas. Las características definitorias de la disminución del gasto cardíaco mostraron como principal atributo deficiencia de la bomba cardiaca y, para el riesgo, el atributo de probabilidad. Analizados

  13. Biomaterials for cardiac regeneration

    CERN Document Server

    Ruel, Marc

    2015-01-01

    This book offers readers a comprehensive biomaterials-based approach to achieving clinically successful, functionally integrated vasculogenesis and myogenesis in the heart. Coverage is multidisciplinary, including the role of extracellular matrices in cardiac development, whole-heart tissue engineering, imaging the mechanisms and effects of biomaterial-based cardiac regeneration, and autologous bioengineered heart valves. Bringing current knowledge together into a single volume, this book provides a compendium to students and new researchers in the field and constitutes a platform to allow for future developments and collaborative approaches in biomaterials-based regenerative medicine, even beyond cardiac applications. This book also: Provides a valuable overview of the engineering of biomaterials for cardiac regeneration, including coverage of combined biomaterials and stem cells, as well as extracellular matrices Presents readers with multidisciplinary coverage of biomaterials for cardiac repair, including ...

  14. Initial Efficacy of a Cardiac Rehabilitation Transition Program: Cardiac TRUST

    OpenAIRE

    Dolansky, Mary A.; Zullo, Melissa; Boxer, Rebecca; Moore, Shirley M.

    2011-01-01

    Patients recovering from cardiac events are increasingly using postacute care, such as home health care and skilled nursing facility services. The purpose of this pilot study was to test the initial efficacy, feasibility, and safety of a specially designed postacute care transitional rehabilitation intervention for cardiac patients. Cardiac Transitional Rehabilitation Using Self- Management Techniques (Cardiac TRUST) is a family-focused intervention that includes progressive low-intensity wal...

  15. Pediatric cardiac postoperative care

    Directory of Open Access Journals (Sweden)

    Auler Jr. José Otávio Costa

    2002-01-01

    Full Text Available The Heart Institute of the University of São Paulo, Medical School is a referral center for the treatment of congenital heart diseases of neonates and infants. In the recent years, the excellent surgical results obtained in our institution may be in part due to modern anesthetic care and to postoperative care based on well-structured protocols. The purpose of this article is to review unique aspects of neonate cardiovascular physiology, the impact of extracorporeal circulation on postoperative evolution, and the prescription for pharmacological support of acute cardiac dysfunction based on our cardiac unit protocols. The main causes of low cardiac output after surgical correction of heart congenital disease are reviewed, and methods of treatment and support are proposed as derived from the relevant literature and our protocols.

  16. Cardiac rehabilitation

    Science.gov (United States)

    ... rehab; Heart failure - cardiac rehab References Anderson L, Taylor RS. Cardiac rehabilitation for people with heart disease: ... of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed ...

  17. Dynamic NMR cardiac imaging in a piglet

    International Nuclear Information System (INIS)

    Doyle, M.; Rzedzian, R.; Mansfield, P.; Coupland, R.E.

    1983-01-01

    NMR echo-planar imaging (EPI) has been used in a real-time mode to visualise the thorax of a live piglet. Moving pictures are available on an immediate image display system which demonstrates dynamic cardiac function. Frame rates vary from one per cardiac cycle in a prospective stroboscopic mode with immediate visual output to a maximum of 10 frames per second yielding up to six looks in one piglet heart cycle, but using a visual playback mode. A completely new system has been used to obtain these images, features of which include a probe assembly with 22 cm access and an AP400 array processor for real-time data processing. (author)

  18. Output hardcopy devices

    CERN Document Server

    Durbeck, Robert

    1988-01-01

    Output Hardcopy Devices provides a technical summary of computer output hardcopy devices such as plotters, computer output printers, and CRT generated hardcopy. Important related technical areas such as papers, ribbons and inks, color techniques, controllers, and character fonts are also covered. Emphasis is on techniques primarily associated with printing, as well as the plotting capabilities of printing devices that can be effectively used for computer graphics in addition to their various printing functions. Comprised of 19 chapters, this volume begins with an introduction to vector and ras

  19. CMAQ Model Output

    Data.gov (United States)

    U.S. Environmental Protection Agency — CMAQ and CMAQ-VBS model output. This dataset is not publicly accessible because: Files too large. It can be accessed through the following means: via EPA's NCC tape...

  20. WRF Model Output

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset contains WRF model output. There are three months of data: July 2012, July 2013, and January 2013. For each month, several simulations were made: A...

  1. VMS forms Output Tables

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These output tables contain parsed and format validated data from the various VMS forms that are sent from any given vessel, while at sea, from the VMS devices on...

  2. Maternal cardiac metabolism in pregnancy

    Science.gov (United States)

    Liu, Laura X.; Arany, Zolt

    2014-01-01

    Pregnancy causes dramatic physiological changes in the expectant mother. The placenta, mostly foetal in origin, invades maternal uterine tissue early in pregnancy and unleashes a barrage of hormones and other factors. This foetal ‘invasion’ profoundly reprogrammes maternal physiology, affecting nearly every organ, including the heart and its metabolism. We briefly review here maternal systemic metabolic changes during pregnancy and cardiac metabolism in general. We then discuss changes in cardiac haemodynamic during pregnancy and review what is known about maternal cardiac metabolism during pregnancy. Lastly, we discuss cardiac diseases during pregnancy, including peripartum cardiomyopathy, and the potential contribution of aberrant cardiac metabolism to disease aetiology. PMID:24448314

  3. Mathematical cardiac electrophysiology

    CERN Document Server

    Colli Franzone, Piero; Scacchi, Simone

    2014-01-01

    This book covers the main mathematical and numerical models in computational electrocardiology, ranging from microscopic membrane models of cardiac ionic channels to macroscopic bidomain, monodomain, eikonal models and cardiac source representations. These advanced multiscale and nonlinear models describe the cardiac bioelectrical activity from the cell level to the body surface and are employed in both the direct and inverse problems of electrocardiology. The book also covers advanced numerical techniques needed to efficiently carry out large-scale cardiac simulations, including time and space discretizations, decoupling and operator splitting techniques, parallel finite element solvers. These techniques are employed in 3D cardiac simulations illustrating the excitation mechanisms, the anisotropic effects on excitation and repolarization wavefronts, the morphology of electrograms in normal and pathological tissue and some reentry phenomena. The overall aim of the book is to present rigorously the mathematica...

  4. Oil output's changing fortunes

    International Nuclear Information System (INIS)

    Eldridge, D.

    1994-01-01

    The Petroleum Economist, previously the Petroleum Press Service, has been making annual surveys of output levels of petroleum in all the oil-producing countries since its founding in 1934. This article documents trends and changes in the major oil-producing countries output from 1934 until the present. This analysis is linked with the political and historical events accompanying these changes, notably the growth of Middle Eastern oil production, the North Sea finds and most recently, Iraq's invasion of Kuwait in 1990. (UK)

  5. Assessing the psychological factors predicting workers' output ...

    African Journals Online (AJOL)

    The study investigated job security, communication skills, interpersonal relationship and emotional intelligence as correlates of workers' output among local government employees in Oyo State. The research adopted descriptive design of an expose facto type. The research instruments used includes Workers' output scale, ...

  6. Multiple myeloma presenting with high-output heart failure and improving with anti-angiogenesis therapy: two case reports and a review of the literature

    Directory of Open Access Journals (Sweden)

    Robin Jason

    2008-07-01

    Full Text Available Abstract Introduction Common manifestations of multiple myeloma include osteolytic lesions, cytopenias, hypercalcemia, and renal insufficiency. Patients may also exhibit heart failure which is often associated with either past therapy or cardiac amyloidosis. A less recognized mechanism is high-output heart failure. Diuretic therapy in this setting has little efficacy in treating the congested state. Furthermore, effective pharmacotherapy has not been established. We report two patients with multiple myeloma and high-output heart failure who failed diuretic therapy. The patients were given dexamethasone in conjunction with lenalidomide and thalidomide, respectively. Shortly thereafter, each patient demonstrated a significant improvement in symptoms. This is the first report of successful treatment of multiple myeloma-induced high-output failure via the utilization of these agents. Case presentation Two patients with multiple myeloma were evaluated for volume overload. The first was a 50-year-old man with refractory disease. Magnetic resonance imaging demonstrated diffuse marrow replacement throughout the pelvis. Cardiac catheterization conveyed elevated filling pressures and a cardiac output of 15 liters/minute. He quickly decompensated and required mechanical ventilation. The second patient was a 61-year-old man recently diagnosed with multiple myeloma and volume overload. Skeletal survey demonstrated numerous lytic lesions throughout the pelvis. His cardiac catheterization also conveyed elevated filling pressures and a cardiac output of 10 liters/minute. Neither patient responded to diuretic therapy and they were subsequently started on dexamethasone plus lenalidomide and thalidomide, respectively. The first patient's brisk diuresis allowed for extubation within 48 hours after the first dose. He had a net negative fluid balance of 15 liters over 10 days. The second patient also quickly diuresed and on repeat cardiac catheterization, his cardiac

  7. Characteristics of a large sample of candidates for permanent ventricular pacing included in the Biventricular Pacing for Atrio-ventricular Block to Prevent Cardiac Desynchronization Study (BioPace).

    Science.gov (United States)

    Funck, Reinhard C; Mueller, Hans-Helge; Lunati, Maurizio; Piorkowski, Christopher; De Roy, Luc; Paul, Vince; Wittenberg, Michael; Wuensch, David; Blanc, Jean-Jacques

    2014-03-01

    The general clinical profile of European pacemaker recipients who require predominant ventricular pacing (VP) is scarcely known. We examined the demographic and clinical characteristics of the 1808 participants (out of 1833 randomized patients) of the ongoing Biventricular Pacing for Atrio-ventricular Block to Prevent Cardiac Desynchronization (BioPace) study. BioPace recruited patients between May 2003 and September 2007 predominantly in European medical centres. We analysed demographic data and described clinical characteristics and electrophysiological parameters prior to device implantation in 1808 enrolled patients. The mean age ± standard deviation (SD) of the 1808 patients was 73.5 ± 9.2 years, 1235 (68%) were men, 654 (36%) presented without structural heart disease, 547 (30%) had ischemic, 355 (20%) hypertensive, 146 (8%) valvular, and 102 (6%) non-ischemic dilated cardiomyopathy. Mean left ventricular ejection fraction was 55.4 ± 12.3%. The main pacing indications were (a) permanent and intermittent atrioventricular (AV) block in 973 (54%), (b) atrial fibrillation with slow ventricular rate in 313 (17%), and (c) miscellaneous bradyarrhythmias in 522 (29%) patients. Mean QRS duration was 118.5 ± 30.5 ms, left bundle branch block was present in 316 (17%), and atrial tachyarrhythmias in 426 (24%) patients. To the best of our knowledge, this sample is a representative source of description of the general profile of European pacemaker recipients who require predominant VP. Patients' characteristics included advanced age, predominantly male gender, preserved left ventricular systolic function, high-grade AV block, narrow QRS complex, and atrial tachyarrhythmias, the latter being present in nearly one-fourth of the cohort.

  8. Cardiac imaging in adults

    International Nuclear Information System (INIS)

    Jaffe, C.C.

    1987-01-01

    This book approaches adult cardiac disease from the correlative imaging perspective. It includes chest X-rays and angiographs, 2-dimensional echocardiograms with explanatory diagrams for clarity, plus details on digital radiology, nuclear medicine techniques, CT and MRI. It also covers the normal heart, valvular heart disease, myocardial disease, pericardial disease, bacterial endocarditis, aortic aneurysm, cardiac tumors, and congenital heart disease of the adult. It points out those aspects where one imaging technique has significant superiority

  9. Cardiac imaging in adults

    Energy Technology Data Exchange (ETDEWEB)

    Jaffe, C.C.

    1987-01-01

    This book approaches adult cardiac disease from the correlative imaging perspective. It includes chest X-rays and angiographs, 2-dimensional echocardiograms with explanatory diagrams for clarity, plus details on digital radiology, nuclear medicine techniques, CT and MRI. It also covers the normal heart, valvular heart disease, myocardial disease, pericardial disease, bacterial endocarditis, aortic aneurysm, cardiac tumors, and congenital heart disease of the adult. It points out those aspects where one imaging technique has significant superiority.

  10. Uncertainty and variability in computational and mathematical models of cardiac physiology.

    Science.gov (United States)

    Mirams, Gary R; Pathmanathan, Pras; Gray, Richard A; Challenor, Peter; Clayton, Richard H

    2016-12-01

    Mathematical and computational models of cardiac physiology have been an integral component of cardiac electrophysiology since its inception, and are collectively known as the Cardiac Physiome. We identify and classify the numerous sources of variability and uncertainty in model formulation, parameters and other inputs that arise from both natural variation in experimental data and lack of knowledge. The impact of uncertainty on the outputs of Cardiac Physiome models is not well understood, and this limits their utility as clinical tools. We argue that incorporating variability and uncertainty should be a high priority for the future of the Cardiac Physiome. We suggest investigating the adoption of approaches developed in other areas of science and engineering while recognising unique challenges for the Cardiac Physiome; it is likely that novel methods will be necessary that require engagement with the mathematics and statistics community. The Cardiac Physiome effort is one of the most mature and successful applications of mathematical and computational modelling for describing and advancing the understanding of physiology. After five decades of development, physiological cardiac models are poised to realise the promise of translational research via clinical applications such as drug development and patient-specific approaches as well as ablation, cardiac resynchronisation and contractility modulation therapies. For models to be included as a vital component of the decision process in safety-critical applications, rigorous assessment of model credibility will be required. This White Paper describes one aspect of this process by identifying and classifying sources of variability and uncertainty in models as well as their implications for the application and development of cardiac models. We stress the need to understand and quantify the sources of variability and uncertainty in model inputs, and the impact of model structure and complexity and their consequences for

  11. Criticality alarm output device

    International Nuclear Information System (INIS)

    Sasaki, Takashi.

    1994-01-01

    The present invention concerns a device used for detection of a critical accident in facilities which handle nuclear fuels, which especially removes the influences of external noises. Namely, a radiation detector outputs logic signals based on trip signals generated by the change of the radiation dose due to occurrence of a critical accident. The logic signal is sent to a logic judging circuit by way of a transmission path present individually in each of radiation detectors. The radiation detector comprises a first inverting means which sends a signal having a level inverted to a logic signal level to the logic judging circuit passing through a transmission path. The logic judging circuit comprises a second reversing means for inverting the level of the signal from the first inverting means and a signal judging means which outputs a conditional signal when the output sent from the second inverting means and the logic signal sent from the radiation detector arrive simultaneously. With such a constitution, influences of external noises intruded to the transmission path can be removed. (I.S.)

  12. Minimal output sets for identifiability.

    Science.gov (United States)

    Anguelova, Milena; Karlsson, Johan; Jirstrand, Mats

    2012-09-01

    Ordinary differential equation models in biology often contain a large number of parameters that must be determined from measurements by parameter estimation. For a parameter estimation procedure to be successful, there must be a unique set of parameters that can have produced the measured data. This is not the case if a model is not uniquely structurally identifiable with the given set of outputs selected as measurements. In designing an experiment for the purpose of parameter estimation, given a set of feasible but resource-consuming measurements, it is useful to know which ones must be included in order to obtain an identifiable system, or whether the system is unidentifiable from the feasible measurement set. We have developed an algorithm that, from a user-provided set of variables and parameters or functions of them assumed to be measurable or known, determines all subsets that when used as outputs give a locally structurally identifiable system and are such that any output set for which the system is structurally identifiable must contain at least one of the calculated subsets. The algorithm has been implemented in Mathematica and shown to be feasible and efficient. We have successfully applied it in the analysis of large signalling pathway models from the literature. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Effects of Exercise Training on Haematology and Maximal Cardiac Output

    DEFF Research Database (Denmark)

    Bonne, Thomas Christian

    -score and the abnormal blood profile score (ABPS) were generated using the official ABP software. After altitude training, six swimmers exceeded the 99% ABP thresholds: Two swimmers exceeded the OFF-score thresholds at day 7; One swimmer exceeded the OFF-score threshold at day 28; One swimmer exceeded the threshold...... = 0.051) and time to complete 3000 m tended (P = 0.09) to increase in LHTH but not after sea level training. In study III haematological parameters were determined weekly three times before and four times after classical altitude and sea level training and ABP thresholds for [Hb], %ret, OFF...... for %ret at day 14; One swimmer surpassed the ABPS threshold at day 7 and one swimmer exceeded the ABPS threshold 28 days after altitude training. No values exceeded the individual thresholds in the control group. In conclusion, this thesis demonstrated that BV is a main determinant of the exercise induced...

  14. Does bronchial thermodilution allow estimation of cardiac output?

    NARCIS (Netherlands)

    Loer, SA; Wietasch, JKG; Scheeren, TWL

    Objective: Transcapillary heat transfer after injections of cold saline into the right atrium generates bronchial thermodilution curves resembling those observed in the aorta. Under the assumption that no indicator is lost or gained within the pulmonary capillary bed and changes in blood temperature

  15. Pediatric Cardiac Surgery In Eritrea.

    African Journals Online (AJOL)

    The teams consisted of volunteer physicians from Germany, Italy and Switzerland including cardiac surgeons, pediatric cardiologists, cardiac anesthesiologists, pediatric intensivists, perfusionists, and other nursing staff. Each mission has routinely included at least 18 health professionals of different category to maximize the.

  16. Cardiac Rehabilitation

    Science.gov (United States)

    ... may also do muscle-strengthening exercises, such as lifting weights or other resistance training exercises, two or three ... health concerns. Education about nutrition, lifestyle and healthy weight ... the most benefits from cardiac rehabilitation, make sure your exercise and ...

  17. Cardiac MRI

    Science.gov (United States)

    ... such as coronary heart disease, heart valve problems, pericarditis, cardiac tumors, or damage from a heart attack. ... Palpitations Heart Valve Disease Implantable Cardioverter Defibrillators Pacemakers Pericarditis Stress Testing RELATED NEWS April 26, 2013 | News ...

  18. Cardiac Angiosarcoma

    Directory of Open Access Journals (Sweden)

    Monique Esteves Cardoso

    2011-01-01

    Full Text Available Despite cardiac metastases are found in about 20% of cancer deaths, the presence of primary cardiac tumors is rare. Most primary tumors are benign, and malignant tumors comprise about 15%. We report a 21-year-old man with fever, dyspnea, and hemoptysis that was diagnosed with angiosarcoma of the right atrium and pulmonary metastasis. Patient was submitted to surgical tumor resection without adjuvant therapy and died four months after diagnosis.

  19. Cardiac Angiosarcoma

    OpenAIRE

    Cardoso, Monique Esteves; Canale, Leonardo Secchin; Ramos, Rosana Grandelle; Salvador Junior, Edson da Silva; Lachtermacher, Stephan

    2011-01-01

    Despite cardiac metastases are found in about 20% of cancer deaths, the presence of primary cardiac tumors is rare. Most primary tumors are benign, and malignant tumors comprise about 15%. We report a 21-year-old man with fever, dyspnea, and hemoptysis that was diagnosed with angiosarcoma of the right atrium and pulmonary metastasis. Patient was submitted to surgical tumor resection without adjuvant therapy and died four months after diagnosis.

  20. Cardiac Angiosarcoma

    Science.gov (United States)

    Cardoso, Monique Esteves; Canale, Leonardo Secchin; Ramos, Rosana Grandelle; Salvador Junior, Edson da Silva; Lachtermacher, Stephan

    2011-01-01

    Despite cardiac metastases are found in about 20% of cancer deaths, the presence of primary cardiac tumors is rare. Most primary tumors are benign, and malignant tumors comprise about 15%. We report a 21-year-old man with fever, dyspnea, and hemoptysis that was diagnosed with angiosarcoma of the right atrium and pulmonary metastasis. Patient was submitted to surgical tumor resection without adjuvant therapy and died four months after diagnosis. PMID:24826214

  1. Complications after cardiac implantable electronic device implantations

    DEFF Research Database (Denmark)

    Kirkfeldt, Rikke Esberg; Johansen, Jens Brock; Nohr, Ellen Aagaard

    2014-01-01

    Complications after cardiac implantable electronic device (CIED) treatment, including permanent pacemakers (PMs), cardiac resynchronization therapy devices with defibrillators (CRT-Ds) or without (CRT-Ps), and implantable cardioverter defibrillators (ICDs), are associated with increased patient...

  2. Relationship between cardiac function and resting cerebral blood flow

    DEFF Research Database (Denmark)

    Henriksen, Otto M; Jensen, Lars T; Krabbe, Katja

    2014-01-01

    Although both impaired cardiac function and reduced cerebral blood flow are associated with ageing, current knowledge of the influence of cardiac function on resting cerebral blood flow (CBF) is limited. The aim of this study was to investigate the potential effects of cardiac function on CBF. CBF......) and 2.4 l min(-1) m(-2), respectively, in females. No effects of cardiac output or cardiac index on CBF or structural signs of brain ageing were observed. However, fractional brain flow defined as the ratio of total brain flow to cardiac output was inversely correlated with cardiac index (r(2) = 0.22, P...... = 0.008) and furthermore lower in males than in females (8.6% versus 12.5%, P = 0.003). Fractional brain flow was also inversely correlated with cerebral white matter lesion grade, although this effect was not significant when adjusted for age. Frequency analysis of heart rate variability showed...

  3. Site compare scripts and output

    Data.gov (United States)

    U.S. Environmental Protection Agency — Monthly site compare scripts and output used to generate the model/ob plots and statistics in the manuscript. The AQS hourly site compare output files are not...

  4. Débito cardíaco diminuído: revisão sistemática das características definidoras Débito cardíaco disminuído: revisión sistemática de las características definidoras Decreased cardiac output: a systematic review of the defining characteristics

    Directory of Open Access Journals (Sweden)

    Vanessa de Souza

    2011-01-01

    explorada. Se constató la importancia del examen físico, la utilización de técnicas menos invasivas y la necesidad de revisar las características definidoras propuestas a fin de proporcionar claridad y objetividad en la identificación de ese diagnóstico de enfermeríaOBJECTIVES: To characterize the scientific articles related to the NANDA-I nursing diagnosis, decreased cardiac output. Verify those articles that describe the behavior of the defining characteristics of this diagnosis, identifying those that occur with the highest frequency. METHODS: A systematic review of literature published between the years 1985 - 2008 was conducted, using the following databases: Lilacs, SciELO, EMBASE, Medline, Pubmed and Cochrane. RESULTS: The sample included 13 articles which identified 50 defining characteristics. Ten characteristics were noted to occur with high frequency: altered heart rate/rhythm, dyspnea, labile blood pressure, rales, oliguria / anuria, edema, cold skin, fatigue / weakness, decreased peripheral pulses and decreased peripheral perfusion. CONCLUSION: This subject has not been explored in depth in the literature. The importance of physical examination, the use of less invasive techniques, and the need to review the proposed defining characteristics to provide clarity and objectivity in the identification of this nursing diagnosis was identified

  5. Teacher Talk and Language Output

    OpenAIRE

    Haiyan Wang

    2014-01-01

    As an important input and teaching media in foreign language teaching classes, teacher talk (TT) has a great effect on language output. This paper explores the problems related to teacher talk (TT) and language output in practical ELT (English Language Teaching) classroom and presents some suggestions for solving the problems which affect learner' effective language output.

  6. Cardiac radiology: centenary review.

    Science.gov (United States)

    de Roos, Albert; Higgins, Charles B

    2014-11-01

    During the past century, cardiac imaging technologies have revolutionized the diagnosis and treatment of acquired and congenital heart disease. Many important contributions to the field of cardiac imaging were initially reported in Radiology. The field developed from the early stages of cardiac imaging, including the use of coronary x-ray angiography and roentgen kymography, to nowadays the widely used echocardiographic, nuclear medicine, cardiac computed tomographic (CT), and magnetic resonance (MR) applications. It is surprising how many of these techniques were not recognized for their potential during their early inception. Some techniques were described in the literature but required many years to enter the clinical arena and presently continue to expand in terms of clinical application. The application of various CT and MR contrast agents for the diagnosis of myocardial ischemia is a case in point, as the utility of contrast agents continues to expand the noninvasive characterization of myocardium. The history of cardiac imaging has included a continuous process of advances in our understanding of the anatomy and physiology of the cardiovascular system, along with advances in imaging technology that continue to the present day.

  7. Cardiac echinococcosis

    Directory of Open Access Journals (Sweden)

    Ivanović-Krstić Branislava A.

    2002-01-01

    Full Text Available Cardiac hydatid disease is rare. We report on an uncommon hydatid cyst localized in the right ventricular wall, right atrial wall tricuspid valve left atrium and pericard. A 33-year-old woman was treated for cough, fever and chest pain. Cardiac echocardiograpic examination revealed a round tumor (5.8 x 4 cm in the right ventricular free wall and two smaller cysts behind that tumor. There were cysts in right atrial wall and tricuspidal valve as well. Serologic tests for hydatidosis were positive. Computed tomography finding was consistent with diagnosis of hydatid cyst in lungs and right hylar part. Surgical treatment was rejected due to great risk of cardiac perforation. Medical treatment with albendazole was unsuccessful and the patient died due to systemic hydatid involvement of the lungs, liver and central nervous system.

  8. [Cardiac amyloidosis].

    Science.gov (United States)

    Boussabah, Elhem; Zakhama, Lilia; Ksontini, Iméne; Ibn Elhadj, Zied; Boukhris, Besma; Naffeti, Sana; Thameur, Moez; Ben Youssef, Soraya

    2008-09-01

    PREREQUIS: Amyloidosis is a rare infiltrative disease characterized by multiple clinical features. Various organs are involved and the cardiovascular system is a common target of amyloidosis. Cardiac involvement may occur with or without clinical manifestations and is considered as a major prognostic factor. To analyze the clinical features of cardiac involvement, to review actual knowledgement concerning echocardiographic diagnostic and to evaluate recent advances in treatment of the disease. An electronic search of the relevant literature was carried out using Medline and Pubmed. Keys words used for the final search were amyloidosis, cardiopathy and echocardiography. We considered for analysis reviews, studies and articles between 1990 and 2007. Amyloidosis represents 5 to 10% of non ischemic cardiomyoparhies. Cardiac involvement is the first cause of restrictive cardiomyopathy witch must be evoked in front of every inexplained cardiopathy after the age of forty. The amyloid nature of cardiopathy is suggered if some manifestations were associated as a peripheric neuropathy, a carpal tunnel sydrome and proteinuria > 3g/day. Echocardiography shows dilated atria, a granular sparkling appearance of myocardium, diastolic dysfunction and thickened left ventricle contrasting with a low electric voltage. The proof of amyloidosis is brought by an extra-cardiac biopsy, the indications of endomyocardial biopsy are very limited. The identification of the amyloid nature of cardiopathy has an direct therapeutic implication: it indicates the use of digitalis, calcium channel blockers and beta-blockers. Today the treatment of amyloidosis remains very unsatisfactory especially in the cardiac involvement. An early diagnosis before the cardiac damage may facilitate therapy and improve prognosis.

  9. Waste treatment in physical input-output analysis

    NARCIS (Netherlands)

    Dietzenbacher, E

    2005-01-01

    When compared to monetary input-output tables (MIOTs), a distinctive feature of physical input-output tables (PIOTs) is that they include the generation of waste as part of a consistent accounting framework. As a consequence, however, physical input-output analysis thus requires that the treatment

  10. Risk factors for low cardiac output syndrome after coronary artery bypass grafting surgery Fatores de risco para síndrome de baixo débito cardíaco após cirurgia de revascularização miocárdica

    Directory of Open Access Journals (Sweden)

    Michel Pompeu Barros de Oliveira Sá

    2012-06-01

    Full Text Available OBJECTIVES: Low cardiac output syndrome (LCOS is a serious complication after cardiac surgery and is associated with significant morbidity and mortality. The aim of this study is to identify risk factors for LCOS in patients undergoing coronary artery bypass grafting (CABG in the Division of Cardiovascular Surgery of Pronto Socorro Cardiológico de Pernambuco - PROCAPE (Recife, PE, Brazil. METHODS: A historical prospective study comprising 605 consecutive patients operated between May 2007 and December 2010. We evaluated 12 preoperative and 7 intraoperative variables. We applied univariate and multivariate logistic regression analysis. RESULTS: The incidence of LCOS was 14.7% (n = 89, with a lethality rate of 52.8% (n = 47. In multivariate analysis by logistic regression, four variables remained as independent risk factors: age > 60 years (OR 2.00, 95% CI 1.20 to 6.14, P = 0.009, on-pump CABG (OR 2.16, 95% CI 1.40 to 7.08, P = 0.006, emergency surgery (OR 4.71, 95% CI 1.34 to 26.55, P = 0.028, incomplete revascularization (OR 2.62, 95% CI 1.32 to 5.86, P = 0.003, and ejection fraction 60 years of off-pump CABG, emergency surgery, incomplete CABG and ejection fraction OBJETIVOS: A síndrome de baixo débito cardíaco (SBDC é uma complicação grave após cirurgias cardíacas, estando associada à significativa morbidade e mortalidade. O objetivo deste estudo é identificar fatores de risco para SBDC em pacientes submetidos à cirurgia de revascularização miocárdica (CRM, na Divisão de Cirurgia Cardiovascular do Pronto Socorro Cardiológico de Pernambuco - PROCAPE (Recife, PE, Brasil. MÉTODOS: Estudo prospectivo histórico compreendendo 605 pacientes consecutivos operados entre maio de 2007 e dezembro de 2010. Avaliaram-se 12 variáveis pré-operatórias e sete variáveis intraoperatórias. Aplicaram-se análises univariada e multivariada por regressão logística. RESULTADOS: A incidência de SBDC foi de 14,7% (n = 89, com taxa de

  11. Mechanisms of Cardiac Regeneration

    Science.gov (United States)

    Uygur, Aysu; Lee, Richard T.

    2016-01-01

    Adult humans fail to regenerate their hearts following injury, and this failure to regenerate myocardium is a leading cause of heart failure and death worldwide. Although all adult mammals appear to lack significant cardiac regeneration potential, some vertebrates can regenerate myocardium throughout life. In addition, new studies indicate that mammals have cardiac regeneration potential during development and very soon after birth. The mechanisms of heart regeneration among model organisms, including neonatal mice, appear remarkably similar. Orchestrated waves of inflammation, matrix deposition and remodeling, and cardiomyocyte proliferation are commonly seen in heart regeneration models. Understanding why adult mammals develop extensive scarring instead of regeneration is a crucial goal for regenerative biology. PMID:26906733

  12. Sudden cardiac death

    DEFF Research Database (Denmark)

    Hougen, H P; Valenzuela, Antonio Jesus Sanchez; Lachica, E

    1992-01-01

    The study deals with the comparison of morphological, histochemical and biochemical methods applied to the detection of myocardial infarction in 150 medico-legal autopsies performed at the Institute of Forensic Pathology in Copenhagen. The study also included an NBT (formazan) test of cardiac cross...

  13. Serial Input Output

    Energy Technology Data Exchange (ETDEWEB)

    Waite, Anthony; /SLAC

    2011-09-07

    Serial Input/Output (SIO) is designed to be a long term storage format of a sophistication somewhere between simple ASCII files and the techniques provided by inter alia Objectivity and Root. The former tend to be low density, information lossy (floating point numbers lose precision) and inflexible. The latter require abstract descriptions of the data with all that that implies in terms of extra complexity. The basic building blocks of SIO are streams, records and blocks. Streams provide the connections between the program and files. The user can define an arbitrary list of streams as required. A given stream must be opened for either reading or writing. SIO does not support read/write streams. If a stream is closed during the execution of a program, it can be reopened in either read or write mode to the same or a different file. Records represent a coherent grouping of data. Records consist of a collection of blocks (see next paragraph). The user can define a variety of records (headers, events, error logs, etc.) and request that any of them be written to any stream. When SIO reads a file, it first decodes the record name and if that record has been defined and unpacking has been requested for it, SIO proceeds to unpack the blocks. Blocks are user provided objects which do the real work of reading/writing the data. The user is responsible for writing the code for these blocks and for identifying these blocks to SIO at run time. To write a collection of blocks, the user must first connect them to a record. The record can then be written to a stream as described above. Note that the same block can be connected to many different records. When SIO reads a record, it scans through the blocks written and calls the corresponding block object (if it has been defined) to decode it. Undefined blocks are skipped. Each of these categories (streams, records and blocks) have some characteristics in common. Every stream, record and block has a name with the condition that each

  14. Moderate-Intensity Exercise Affects Gut Microbiome Composition and Influences Cardiac Function in Myocardial Infarction Mice

    Directory of Open Access Journals (Sweden)

    Zuheng Liu

    2017-09-01

    Full Text Available Physical exercise is commonly regarded as protective against cardiovascular disease (CVD. Recent studies have reported that exercise alters the gut microbiota and that modification of the gut microbiota can influence cardiac function. Here, we focused on the relationships among exercise, the gut microbiota and cardiac function after myocardial infarction (MI. Four-week-old C57BL/6J mice were exercised on a treadmill for 4 weeks before undergoing left coronary artery ligation. Cardiac function was assessed using echocardiography. Gut microbiomes were evaluated post-exercise and post-MI using 16S rRNA gene sequencing on an Illumina HiSeq platform. Exercise training inhibited declines in cardiac output and stroke volume in post-MI mice. In addition, physical exercise and MI led to alterations in gut microbial composition. Exercise training increased the relative abundance of Butyricimonas and Akkermansia. Additionally, key operational taxonomic units were identified, including 24 lineages (mainly from Bacteroidetes, Barnesiella, Helicobacter, Parabacteroides, Porphyromonadaceae, Ruminococcaceae, and Ureaplasma that were closely related to exercise and cardiac function. These results suggested that exercise training improved cardiac function to some extent in addition to altering the gut microbiota; therefore, they could provide new insights into the use of exercise training for the treatment of CVD.

  15. Unstable resonator with multiple outputs

    Science.gov (United States)

    Konopnicki, M. J.; Smithers, M. E.

    1983-03-01

    Two or more unstable optical resonators can be coupled together by sharing optical elements. The result is then a single compound resonator with multiple outputs. For identical coupled cavities, the transverse structure of the outputs would be identical. In general, there will be misalignments and other aberrations that will vary from cavity to cavity. The cumulative effects of such aberrations are treated using both analytical and numerical approaches. It is shown that the average output of a multioutput resonator is the same as the output of a single uncoupled resonator with aberrations equal to the average of those contained in the multioutput resonator.

  16. The use of pneumoperitoneum during laparoscopic surgery as a model to study pathophysiologic phenomena: the correlation of cardiac functionality with computerized acoustic indices--preliminary data.

    Science.gov (United States)

    Bickel, Amitai; Eitan, Arieh; Melnik, Dimitry; Weiss, Atalia; Gavrieli, Noam; Kniaz, David; Intrator, Nathan

    2012-05-01

    Induction of pneumoperitoneum during laparoscopic surgery leads to diverse cardiovascular changes that can be used as a model to study pathophysiologic phenomena. Application of novel signal processing and figure extraction enabled searching for correlation between various signals and pathophysiologic setting. Our aim was to quantitatively correlate cardiac functionality (as expressed by cardiac output) with the spectral energy of the first heart sound (S1) obtained from the phonocardiogram, during laparoscopic surgery. Patients who were scheduled for elective laparoscopic operations were enrolled in the study. Cardiac output was maximally changed during anesthesia and abdominal insufflation and was obtained from the arterial pressure wave (FloTrac™ sensor and Vigileo™ monitor [Edwards Lifesciences Ltd.]). Heart signals were recorded during surgery from each subject by a computerized digital data acquisition system. The automatic analysis of the heart sounds included segmentation that was based on the energy envelope of the heart sounds together with analysis of the electrocardiogram signal. We analyzed the morphology of the sounds using hierarchial cluster analysis to remove those sounds that were not reliably recorded. The magnitude of the amplitude of heart sounds was obtained by using the Hilbert transform for each heartbeat. Statistical analysis was based on linear regression. Following exclusion of 3 patients (mainly because of technical reasons), we were left with 7 patients who demonstrated statistically significant positive correlation between cardiac index and the amplitude of S1 (regression coefficient between 0.4 and 0.9, Pfunctionality, through sophisticated computerized analysis, using the pneumoperitoneum model for changing the cardiac output.

  17. Farm-Level Determinants of output Commercialization:

    African Journals Online (AJOL)

    MARC-AB

    The analytical setup of the determinant factors included in this study has benefited from field observations and the various crop output market participation studies. (Pender and Dawit, 2007; Goitom, 2009; Tufa, et. al., 2014) conducted elsewhere in the country. However, it should be noted that other factors related to the ...

  18. Acupuncture therapy related cardiac injury.

    Science.gov (United States)

    Li, Xue-feng; Wang, Xian

    2013-12-01

    Cardiac injury is the most serious adverse event in acupuncture therapy. The causes include needling chest points near the heart, the cardiac enlargement and pericardial effusion that will enlarge the projected area on the body surface and make the proper depth of needling shorter, and the incorrect needling method of the points. Therefore, acupuncture practitioners must be familiar with the points of the heart projected area on the chest and the correct needling methods in order to reduce the risk of acupuncture therapy related cardiac injury.

  19. Input-output maps are strongly biased towards simple outputs.

    Science.gov (United States)

    Dingle, Kamaludin; Camargo, Chico Q; Louis, Ard A

    2018-02-22

    Many systems in nature can be described using discrete input-output maps. Without knowing details about a map, there may seem to be no a priori reason to expect that a randomly chosen input would be more likely to generate one output over another. Here, by extending fundamental results from algorithmic information theory, we show instead that for many real-world maps, the a priori probability P(x) that randomly sampled inputs generate a particular output x decays exponentially with the approximate Kolmogorov complexity [Formula: see text] of that output. These input-output maps are biased towards simplicity. We derive an upper bound P(x) ≲ [Formula: see text], which is tight for most inputs. The constants a and b, as well as many properties of  P(x), can be predicted with minimal knowledge of the map. We explore this strong bias towards simple outputs in systems ranging from the folding of RNA secondary structures to systems of coupled ordinary differential equations to a stochastic financial trading model.

  20. Débito cardíaco e fração de ejeção fetal por meio do spatio-temporal image correlation (STIC: comparação entre fetos masculinos e femininos Fetal cardiac output and ejection fraction by spatio-temporal image correlation (STIC: comparison between male and female fetuses

    Directory of Open Access Journals (Sweden)

    Christiane Simioni

    2012-06-01

    Full Text Available OBJETIVO: Comparar do débito cardíaco (DC e a fração de ejeção (FE do coração de fetos masculinos e femininos obtidos por meio da ultrassonografia tridimensional, utilizando o spatio-temporal image correlation (STIC. MÉTODOS: Realizou-se um estudo de corte transversal com 216 fetos normais, entre 20 a 34 semanas de gestação, sendo 108 masculinos e 108 femininos. Os volumes ventriculares no final da sístole e diástole foram obtidos por meio do STIC, sendo as avaliações volumétricas realizadas pelo virtual organ computer-aided analysis (VOCAL com rotação de 30º. Para o cálculo do DC utilizou-se a fórmula: DC= volume sistólico/frequência cardíaca fetal, enquanto que para a FE utilizou-se a fórmula: FE= volume sistólico/volume diastólico final. O DC (combinado, feminino e masculino e a FE (masculina e feminina foram comparadas utilizando-se o teste t não pareado e ANCOVA. Foram criados gráficos de dispersão com os percentis 5, 50 e 95. RESULTADOS: A média do DC combinado, DC direito, DC esquerdo, FE direita e FE esquerda, para feminino e masculino, foram 240,07 mL/min; 122,67 mL/min; 123,40 mL/min; 72,84%; 67,22%; 270,56 mL/min; 139,22 mL/min; 131,34 mL/min; 70,73% e 64,76%, respectivamente; sem diferença estatística (P> 0,05. CONCLUSÕES: O DC e a FE fetal obtidos por meio da ultrassonografia tridimensional (STIC não apresentaram diferença significativa em relação ao gênero.OBJECTIVE: To compare the cardiac output (CO and ejection fraction (EF of the heart of male and female fetuses obtained by 3D-ultrasonography using spatio-temporal image correlation (STIC. METHODS: We conducted a cross-sectional study with 216 normal fetuses, between 20 and 34 weeks of gestation, 108 male and 108 female. Ventricular volumes at the end of systole and diastole were obtained by STIC, and the volumetric assessments performed by the virtual organ computer-aided analysis (VOCAL rotated 30º. To calculate the DC used the formula

  1. Estimativa não-invasiva do débito cardíaco durante o exercício a partir de impedância cardiográfica e consumo de oxigênio em idosos Non-invasive estimate of cardiac output during exercise based on impedance cardiography and oxygen uptake in the elderly

    Directory of Open Access Journals (Sweden)

    Maurício Nunes Rodrigues

    2007-01-01

    Full Text Available OBJETIVO: O presente estudo analisou a concordância entre as estimativas do débito cardíaco (Q geradas por dois métodos indiretos e sua aplicabilidade em 54 homens e 77 mulheres (60-90 anos. MÉTODOS: Os indivíduos realizaram um teste cardiopulmonar de exercício progressivo máximo em ciclo-ergômetro. O Q foi estimado a partir do consumo de oxigênio e da impedância cardiográfica a 50% e 100% da carga máxima alcançada no teste (Wmáx. Os limites de concordância e as diferenças médias (vieses foram avaliados segundo a metodologia proposta por Bland e Altman, enquanto a relação entre os métodos foi analisada por regressão linear e correlação intraclasse (ICC. RESULTADOS: Na carga equivalente a 50% Wmáx, a diferença entre as médias dos métodos foi de -0,58 L•min-1 (6,3% menor para a medida da impedância, e o limite de concordância de ± 2,54 L•min-1 (24,7%. Em 100% Wmáx, a diferença foi de 1,03 L•min-1 (8,5% maior para a medida da impedância, com um limite de concordância de ± 3,35 L•min-1 (27,6%. Os valores de ICC e as curvas de regressão obtidas entre os métodos foram: Qimp=1,82+0,75Q VO2 (r²=0,765, pOBJECTIVE: This study assessed the agreement between cardiac output (Q measurements generated by two indirect methods and their applicability in 54 men e 77 women (aged 60-90. METHODS: The subjects performed a cardiopulmonary test with incremental to maximal exercise on a cycle-ergometer. "Q" was estimated based on oxygen uptake and on impedance cardiography at 50% and 100% of the maximal workload (Wmax reached during the test. The limits of agreement and mean differences (biases were estimated using the methodology proposed by Bland-Altman, whereas the relationship between the methods was analyzed by linear regression and intra-class correlation (ICC. RESULTS: For the load equivalent do 50% of Wmax, the bias between the means of the two methods was -0.58 L•min-1 (6.3% smaller for the impedance measurement

  2. [Remifentanil does not increase urine output during oral surgery, contrary to its effect during other surgeries - a cohort study].

    Science.gov (United States)

    Ouchi, Kentaro; Sugiyama, Kazuna

    An increase in urine output by remifentanil injection during laparoscopic procedures and surgeries such as cardiac and gynecological procedures, due to suppression of the stress response to surgery, has been reported. The aim of our prospective, observational, cohort study was to assess the effect of remifentanil analgesia on urine output during dental and minor oral surgery by comparing intraoperative urine output under defined infusion volumes with and without the use of remifentanil. Dental patients aged 16 years or older, American Society of Anesthesiologists physical status 1, with no renal diseases or abnormal blood values of serum creatinine and BUN, not on treatment with diuretic drugs, and undergoing minor oro-maxillofacial surgery or dental treatment under inhalation general anesthesia were included in this study. Urethral catheterization was performed after anesthesia induction, and urine output was measured every 30minutes. We measured urine volume (mL) and rate of urine output (mL.kg -1 .h -1 ) intraoperatively, and compared these parameters between patients who did and did not receive remifentanil during the intraoperative period. Eighty-seven patients were categorized into the remifentanil group (n=43) or remifentanil non-use group (n=44). Both volume of urine (mL) and rate of urine output (mL.kg -1 .h -1 ) were not significantly different between the two groups (remifentanil group, 372.3±273.5mL, 1.8±1.1mL.kg -1 .h -1 ; remifentanil non-use group, 343.3±283.3mL, 1.9±1.2mL.kg -1 .h -1 ; p=0.63; 0.57). Our results show that use of remifentanil during dental and minor oral surgeries does not increase urine output. Copyright © 2016 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

  3. Cardiac conduction system

    Science.gov (United States)

    The cardiac conduction system is a group of specialized cardiac muscle cells in the walls of the heart that send signals to the ... contract. The main components of the cardiac conduction system are the SA node, AV node, bundle of ...

  4. Cardiac tamponade: contrast reflux as an indicator of cardiac chamber equalization

    Directory of Open Access Journals (Sweden)

    Nauta Foeke Jacob

    2012-05-01

    Full Text Available Abstract Background Traumatic hemopericardium remains a rare entity; it does however commonly cause cardiac tamponade which remains a major cause of death in traumatic blunt cardiac injury. Objectives We present a case of blunt chest trauma complicated by cardiac tamponade causing cardiac chamber equalization revealed by reflux of contrast. Case report A 29-year-old unidentified male suffered blunt chest trauma in a motor vehicle collision. Computed tomography (CT demonstrated a periaortic hematoma and hemopericardium. Significant contrast reflux was seen in the inferior vena cava and hepatic veins suggesting a change in cardiac chamber pressures. After intensive treatment including cardiac massage this patient expired of cardiac arrest. Conclusion Reflux of contrast on CT imaging can be an indicator of traumatic cardiac tamponade.

  5. Metoclopramide-induced cardiac arrest

    Directory of Open Access Journals (Sweden)

    Martha M. Rumore

    2011-11-01

    Full Text Available The authors report a case of cardiac arrest in a patient receiving intravenous (IV metoclopramide and review the pertinent literature. A 62-year-old morbidly obese female admitted for a gastric sleeve procedure, developed cardiac arrest within one minute of receiving metoclopramide 10 mg via slow intravenous (IV injection. Bradycardia at 4 beats/min immediately appeared, progressing rapidly to asystole. Chest compressions restored vital function. Electrocardiogram (ECG revealed ST depression indicative of myocardial injury. Following intubation, the patient was transferred to the intensive care unit. Various cardiac dysrrhythmias including supraventricular tachycardia (SVT associated with hypertension and atrial fibrillation occurred. Following IV esmolol and metoprolol, the patient reverted to normal sinus rhythm. Repeat ECGs revealed ST depression resolution without pre-admission changes. Metoclopramide is a non-specific dopamine receptor antagonist. Seven cases of cardiac arrest and one of sinus arrest with metoclopramide were found in the literature. The metoclopramide prescribing information does not list precautions or adverse drug reactions (ADRs related to cardiac arrest. The reaction is not dose related but may relate to the IV administration route. Coronary artery disease was the sole risk factor identified. According to Naranjo, the association was possible. Other reports of cardiac arrest, severe bradycardia, and SVT were reviewed. In one case, five separate IV doses of 10 mg metoclopramide were immediately followed by asystole repeatedly. The mechanism(s underlying metoclopramide’s cardiac arrest-inducing effects is unknown. Structural similarities to procainamide may play a role. In view of eight previous cases of cardiac arrest from metoclopramide having been reported, further elucidation of this ADR and patient monitoring is needed. Our report should alert clinicians to monitor patients and remain diligent in surveillance and

  6. Cardiac cone-beam CT

    International Nuclear Information System (INIS)

    Manzke, Robert

    2005-01-01

    This doctoral thesis addresses imaging of the heart with retrospectively gated helical cone-beam computed tomography (CT). A thorough review of the CT reconstruction literature is presented in combination with a historic overview of cardiac CT imaging and a brief introduction to other cardiac imaging modalities. The thesis includes a comprehensive chapter about the theory of CT reconstruction, familiarizing the reader with the problem of cone-beam reconstruction. The anatomic and dynamic properties of the heart are outlined and techniques to derive the gating information are reviewed. With the extended cardiac reconstruction (ECR) framework, a new approach is presented for the heart-rate-adaptive gated helical cardiac cone-beam CT reconstruction. Reconstruction assessment criteria such as the temporal resolution, the homogeneity in terms of the cardiac phase, and the smoothness at cycle-to-cycle transitions are developed. Several reconstruction optimization approaches are described: An approach for the heart-rate-adaptive optimization of the temporal resolution is presented. Streak artifacts at cycle-to-cycle transitions can be minimized by using an improved cardiac weighting scheme. The optimal quiescent cardiac phase for the reconstruction can be determined automatically with the motion map technique. Results for all optimization procedures applied to ECR are presented and discussed based on patient and phantom data. The ECR algorithm is analyzed for larger detector arrays of future cone-beam systems throughout an extensive simulation study based on a four-dimensional cardiac CT phantom. The results of the scientific work are summarized and an outlook proposing future directions is given. The presented thesis is available for public download at www.cardiac-ct.net

  7. Output

    DEFF Research Database (Denmark)

    Mehlsen, Camilla

    2010-01-01

    Hvad får vi egentlig ud af internationale komparative undersøgelser som PISA, PIRLS og TIMSS? Hvordan påvirker de dansk uddannelsespolitik? Asterisk har talt med tre forskere med ekspertise på området.......Hvad får vi egentlig ud af internationale komparative undersøgelser som PISA, PIRLS og TIMSS? Hvordan påvirker de dansk uddannelsespolitik? Asterisk har talt med tre forskere med ekspertise på området....

  8. Measuring the Technical Efficiency of Farms Producing Environmental Output: Parametric and Semiparametric Estimation of Multi-output Stochastic Ray Production Frontiers

    OpenAIRE

    Tomasz Gerard Czekaj

    2013-01-01

    This paper investigates the technical efficiency of Polish dairy farms producing environmental output using the stochastic ray function to model multi-output – multi-input technology. Two general models are considered. One which neglects the provision of environmental output and one which accounts for such output. Three different proxies of environmental output are discussed: the ratio of permanent grassland (including rough grazing) to total agricultural area, the total area of permanent gra...

  9. Cardiac pacemaker

    International Nuclear Information System (INIS)

    Kolenik, S.A.

    1976-01-01

    The construction of a cardiac pacemaker is described which is characterized by particularly small dimensions, small weight and long life duration. The weight is under 100g, the specific weight under 1.7. Mass inertia forces which occur through acceleration and retardation processes, thus remain below the threshold values, above which one would have to reckon with considerable damaging of the surrounding body tissue. The maintaining of small size and slight weight is achieved by using an oscillator on COSMOS basis, where by considerably lower energy consumption, amongst others the lifetimes of the batteries used - a lithium anode with thionyl chloride electrolyte - is extended to over 5 years. The reliability can be increased by the use of 2 or more batteries. The designed dimension are 20x60x60 mm 3 . (ORU/LH) [de

  10. Selective arterialization of a cardiac vein in a model of cardiac microangiopathy and macroangiopathy in sheep.

    Science.gov (United States)

    Resetar, Michaela Elisabeth; Ullmann, Cris; Broeske, Petra; Ludwig-Schindler, Kristin; Doll, Nicolas K; Salameh, Aida; Dhein, Stefan; Mohr, Friedrich W

    2007-05-01

    Some patients with significant arteriosclerosis of the heart are not amenable to revascularization of a coronary artery because they have a combination of microangiopathy and significant macroangiopathy. We investigated the benefit of arterialization of a cardiac vein under these circumstances in an acute animal model. In the hearts of 8 sheep, microspheres were injected into the left coronary artery; 60 minutes later, a stenosis of the left anterior descending artery was performed. After 45 minutes, retrograde venous revascularization was performed by sewing the left internal thoracic artery to the concomitant vein of the left anterior descending artery in a beating-heart technique. For flow reversal, the vein was ligated proximally to the anastomosis. The efficiency of the bypass graft was evaluated by coronary angiography and flow measurement. Cardiac output, electrocardiography, and mean arterial blood pressure were assessed in each phase of the experiment. The ischemic state of the myocardium was confirmed by a significant decrease of cardiac output, stroke volume, and mean arterial blood pressure, and a significant elevation of the ST segment in the electrocardiography. After retrograde venous revascularization was established, cardiac output and stroke volume increased and ST elevations decreased. The grafts showed adequate flow (26.15 +/- 2.08 mL/min), and reversed blood flow in the grafted vein was proved by coronary angiography. Retrograde venous revascularization is possible and improves cardiac function in a state of acute ischemia caused by a combination of microangiopathy and macroangiopathy.

  11. Research management and research output

    Directory of Open Access Journals (Sweden)

    Anita Bosch

    2011-12-01

    Full Text Available Purpose: A study was conducted at two merged South African higher education institutions to determine which management factors, as identified in a literature study as well as through a factor analysis of survey data, were predictive of the dependent variable 'research output'. Problem investigated: Research output contributes to creating sustainability of knowledge of management sciences and therefore the active management of research is in the interest of progressive universities. Research management related activities are usually associated with measurable targets, detailed plans, rigorous evaluation and decisive action - all of which are observable (perhaps programmable behaviour also referred to as tangible factors. Authors argue that the tangible factors of any successful institution can be copied, technology can be bought, and in theory you should have an instantly thriving research institution. It is, however, clear that although many institutions have exactly the same technology and structure as their successful competitors, they still fail to succeed in increasing research output. Design and Research methodology or approach: A survey was distributed to n=411 and yielded a 49.6% response rate. A confirmatory reliability analysis as well as a factor analysis was conducted. Findings/implications: The empirical model that was derived through a factor analysis strengthens the argument that both tangible and intangible factors exist in a research environment. Tangible and intangible factors play a different role in predicting research output. The tangible factors are predictors of research output for non-research-active academics. The theoretical research output prediction model highlights predictors such as 'professional activities' and 'individual skills and competence' for specific groupings. The theoretical model indicates that the factors that predict research output are largely intrinsic to a researcher but could also be supported by

  12. Simulation data mapping in virtual cardiac model.

    Science.gov (United States)

    Jiquan, Liu; Jingyi, Feng; Duan, Huilong; Siping, Chen

    2004-01-01

    Although 3D heart and torso model with realistic geometry are basis of simulation computation in LFX virtual cardiac model, the simulation results are mostly output in 2D format. To solve such a problem and enhance the virtual reality of LFX virtual cardiac model, the methods of voxel mapping and vertex project mapping were presented. With these methods, excitation isochrone map (EIM) was mapped from heart model with realistic geometry to real visible man heart model, and body surface potential map (BSPM) was mapped from torso model with realistic geometry to real visible man body surface. By visualizing in the 4Dview, which is a real-time 3D medical image visualization platform, the visualization results of EIM and BSPM simulation data before and after mapping were also provided. According to the visualization results, the output format of EIM and BSPM simulation data of LFX virtual cardiac model were extended from 2D to 4D (spatio-temporal) and from cardiac model with realistic geometry to real cardiac model, and more realistic and effective simulation was achieved.

  13. Defence Output Measures: An Economics Perspective

    Science.gov (United States)

    2011-11-01

    is even more challenging. Economic theory simply asserts the concept of defence output without exploring its definition and multi-product nature...It also protects national interests, including independence and ‘appropriate sovereignty’ (e.g. protecting a nation’s interests in a globalised ...of success in delivering protection. “There is no definitive way of knowing what might have happened, but did not happen, because of the activities

  14. Pregnancy as a cardiac stress model

    Science.gov (United States)

    Chung, Eunhee; Leinwand, Leslie A.

    2014-01-01

    Cardiac hypertrophy occurs during pregnancy as a consequence of both volume overload and hormonal changes. Both pregnancy- and exercise-induced cardiac hypertrophy are generally thought to be similar and physiological. Despite the fact that there are shared transcriptional responses in both forms of cardiac adaptation, pregnancy results in a distinct signature of gene expression in the heart. In some cases, however, pregnancy can induce adverse cardiac events in previously healthy women without any known cardiovascular disease. Peripartum cardiomyopathy is the leading cause of non-obstetric mortality during pregnancy. To understand how pregnancy can cause heart disease, it is first important to understand cardiac adaptation during normal pregnancy. This review provides an overview of the cardiac consequences of pregnancy, including haemodynamic, functional, structural, and morphological adaptations, as well as molecular phenotypes. In addition, this review describes the signalling pathways responsible for pregnancy-induced cardiac hypertrophy and angiogenesis. We also compare and contrast cardiac adaptation in response to disease, exercise, and pregnancy. The comparisons of these settings of cardiac hypertrophy provide insight into pregnancy-associated cardiac adaptation. PMID:24448313

  15. Using deflation in the pole assignment problem with output feedback

    Science.gov (United States)

    Miminis, George

    1989-01-01

    A direct algorithm is suggested for the computation of a linear output feedback for a multi input, multi output system such that the resultant closed-loop matrix has eigenvalues that include a specified set of eigenvalues. The algorithm uses deflation based on unitary similarity transformations. Thus researchers hope the algorithm is numerically stable; however, this has not been proven as yet.

  16. Temperate climate - Innovative outputs nexus

    NARCIS (Netherlands)

    Coccia, M.

    2014-01-01

    Technological change is a vital human activity that interacts with geographic factors and environment. The purpose of the study here is to analyse the relationship between geo-climate zones of the globe and technological outputs in order to detect favourable areas that spur higher technological

  17. Remote input/output station

    CERN Multimedia

    1972-01-01

    A general view of the remote input/output station installed in building 112 (ISR) and used for submitting jobs to the CDC 6500 and 6600. The card reader on the left and the line printer on the right are operated by programmers on a self-service basis.

  18. Kilder til output-legitimitet

    DEFF Research Database (Denmark)

    Pedersen, Morten Jarlbæk

    2016-01-01

    Diskussioner om legitimitet i den Europæiske Union bygger ofte på det teoretiske skel mellem output-legitimitet og andre former for legitimitet. Dette skyldes ikke mindst, at netop Unionens evne til at levere reale løsninger på reale problemer er en væsentlig – hvis ikke den væsentligste – kilde ...

  19. World Input-Output Network.

    Directory of Open Access Journals (Sweden)

    Federica Cerina

    Full Text Available Production systems, traditionally analyzed as almost independent national systems, are increasingly connected on a global scale. Only recently becoming available, the World Input-Output Database (WIOD is one of the first efforts to construct the global multi-regional input-output (GMRIO tables. By viewing the world input-output system as an interdependent network where the nodes are the individual industries in different economies and the edges are the monetary goods flows between industries, we analyze respectively the global, regional, and local network properties of the so-called world input-output network (WION and document its evolution over time. At global level, we find that the industries are highly but asymmetrically connected, which implies that micro shocks can lead to macro fluctuations. At regional level, we find that the world production is still operated nationally or at most regionally as the communities detected are either individual economies or geographically well defined regions. Finally, at local level, for each industry we compare the network-based measures with the traditional methods of backward linkages. We find that the network-based measures such as PageRank centrality and community coreness measure can give valuable insights into identifying the key industries.

  20. Molecular nuclear cardiac imaging

    International Nuclear Information System (INIS)

    Lee, Dong Soo; Paeng, Jin Chul

    2004-01-01

    Molecular nuclear cardiac imaging has included Tc-99m Annexin imaging to visualize myocardial apoptosis, but is now usually associated with gene therapy and cell-based therapy. Cardiac gene therapy was not successful so far but cardiac reporter gene imaging was made possible using HSV-TK (herpes simplex virus thymidine kinase) and F-18 FHBG (fluoro-hydroxymethylbutyl guanine) or I-124 FIAU (fluoro-deoxyiodo-arabino-furanosyluracil). Gene delivery was performed by needle injection with or without catheter guidance. TK expression did not last longer than 2 weeks in myocardium. Cell-based therapy of ischemic heart or failing heart looks promising, but biodistribution and differentiation of transplanted cells are not known. Reporter genes can be transfected to the stem/progenitor cells and cells containing these genes can be transplanted to the recipients using catheter-based purging or injection. Repeated imaging should be available and if promoter are varied to let express reporter transgenes, cellular (trans)differentiation can be studied. NIS (sodium iodide symporter) or D2R receptor genes are promising in this aspect

  1. Simulation evaluation of quantitative myocardial perfusion assessment from cardiac CT

    Science.gov (United States)

    Bindschadler, Michael; Modgil, Dimple; Branch, Kelley R.; La Riviere, Patrick J.; Alessio, Adam M.

    2014-03-01

    Contrast enhancement on cardiac CT provides valuable information about myocardial perfusion and methods have been proposed to assess perfusion with static and dynamic acquisitions. There is a lack of knowledge and consensus on the appropriate approach to ensure 1) sufficient diagnostic accuracy for clinical decisions and 2) low radiation doses for patient safety. This work developed a thorough dynamic CT simulation and several accepted blood flow estimation techniques to evaluate the performance of perfusion assessment across a range of acquisition and estimation scenarios. Cardiac CT acquisitions were simulated for a range of flow states (Flow = 0.5, 1, 2, 3 ml/g/min, cardiac output = 3,5,8 L/min). CT acquisitions were simulated with a validated CT simulator incorporating polyenergetic data acquisition and realistic x-ray flux levels for dynamic acquisitions with a range of scenarios including 1, 2, 3 sec sampling for 30 sec with 25, 70, 140 mAs. Images were generated using conventional image reconstruction with additional image-based beam hardening correction to account for iodine content. Time attenuation curves were extracted for multiple regions around the myocardium and used to estimate flow. In total, 2,700 independent realizations of dynamic sequences were generated and multiple MBF estimation methods were applied to each of these. Evaluation of quantitative kinetic modeling yielded blood flow estimates with an root mean square error (RMSE) of ~0.6 ml/g/min averaged across multiple scenarios. Semi-quantitative modeling and qualitative static imaging resulted in significantly more error (RMSE = ~1.2 and ~1.2 ml/min/g respectively). For quantitative methods, dose reduction through reduced temporal sampling or reduced tube current had comparable impact on the MBF estimate fidelity. On average, half dose acquisitions increased the RMSE of estimates by only 18% suggesting that substantial dose reductions can be employed in the context of quantitative myocardial

  2. Cardiac regeneration therapy: connections to cardiac physiology.

    Science.gov (United States)

    Takehara, Naofumi; Matsubara, Hiroaki

    2011-12-01

    Without heart transplantation, a large number of patients with failing hearts worldwide face poor outcomes. By means of cardiomyocyte regeneration, cardiac regeneration therapy is emerging with great promise as a means for restoring loss of cardiac function. However, the limited success of clinical trials using bone marrow-derived cells and myoblasts with heterogeneous constituents, transplanted at a wide range of cell doses, has led to disagreement on the efficacy of cell therapy. It is therefore essential to reevaluate the evidence for the efficacy of cell-based cardiac regeneration therapy, focusing on targets, materials, and methodologies. Meanwhile, the revolutionary innovation of cardiac regeneration therapy is sorely needed to help the millions of people who suffer heart failure from acquired loss of cardiomyocytes. Cardiac regeneration has been used only in limited species or as a developing process in the rodent heart; now, the possibility of cardiomyocyte turnover in the human heart is being revisited. In the pursuit of this concept, the use of cardiac stem/progenitor stem cells in the cardiac niche must be focused to usher in a second era of cardiac regeneration therapy for the severely injured heart. In addition, tissue engineering and cellular reprogramming will advance the next era of treatment that will enable current cell-based therapy to progress to "real" cardiac regeneration therapy. Although many barriers remain, the prevention of refractory heart failure through cardiac regeneration is now becoming a realistic possibility.

  3. Mast Cells: Key Contributors to Cardiac Fibrosis

    Directory of Open Access Journals (Sweden)

    Scott P. Levick

    2018-01-01

    Full Text Available Historically, increased numbers of mast cells have been associated with fibrosis in numerous cardiac pathologies, implicating mast cells in the development of cardiac fibrosis. Subsequently, several approaches have been utilised to demonstrate a causal role for mast cells in animal models of cardiac fibrosis including mast cell stabilising compounds, rodents deficient in mast cells, and inhibition of the actions of mast cell-specific proteases such as chymase and tryptase. Whilst most evidence supports a pro-fibrotic role for mast cells, there is evidence that in some settings these cells can oppose fibrosis. A major gap in our current understanding of cardiac mast cell function is identification of the stimuli that activate these cells causing them to promote a pro-fibrotic environment. This review will present the evidence linking mast cells to cardiac fibrosis, as well as discuss the major questions that remain in understanding how mast cells contribute to cardiac fibrosis.

  4. UFO - The Universal FEYNRULES Output

    Science.gov (United States)

    Degrande, Céline; Duhr, Claude; Fuks, Benjamin; Grellscheid, David; Mattelaer, Olivier; Reiter, Thomas

    2012-06-01

    We present a new model format for automatized matrix-element generators, the so-called Universal FEYNRULES Output (UFO). The format is universal in the sense that it features compatibility with more than one single generator and is designed to be flexible, modular and agnostic of any assumption such as the number of particles or the color and Lorentz structures appearing in the interaction vertices. Unlike other model formats where text files need to be parsed, the information on the model is encoded into a PYTHON module that can easily be linked to other computer codes. We then describe an interface for the MATHEMATICA package FEYNRULES that allows for an automatic output of models in the UFO format.

  5. CSI cardiac prevent 2015

    Directory of Open Access Journals (Sweden)

    S Ramakrishnan

    2015-01-01

    Full Text Available The CSI Cardiac Prevent 2015 was held at Hotel Taj Palace, New Delhi, on September 25-27, 2015. The major challenge was to create interest among cardiologists and physicians on preventive cardiology, a neglected area. The theme of the conference was "Innovations in Heart Disease Prevention.′′ This conference included "CSI at WHF Roadmap Workshop, Inauguration Ceremony, scientific program, plenary sessions, Nursing/Dietician track, Industry Exhibition, Social Events," Great India blood pressure Survey, and CSI Smart Heart App. A total of 848 delegates/faculties attended this conference against a total of 1140 people registered for the meeting.

  6. Multi-model MPC with output feedback

    Directory of Open Access Journals (Sweden)

    J. M. Perez

    2014-03-01

    Full Text Available In this work, a new formulation is presented for the model predictive control (MPC of a process system that is represented by a finite set of models, each one corresponding to a different operating point. The general case is considered of systems with stable and integrating outputs in closed-loop with output feedback. For this purpose, the controller is based on a non-minimal order model where the state is built with the measured outputs and the manipulated inputs of the control system. Therefore, the state can be considered as perfectly known and, consequently, there is no need to include a state observer in the control loop. This property of the proposed modeling approach is convenient to extend previous stability results of the closed loop system with robust MPC controllers based on state feedback. The controller proposed here is based on the solution of two optimization problems that are solved sequentially at the same time step. The method is illustrated with a simulated example of the process industry. The rigorous simulation of the control of an adiabatic flash of a multi-component hydrocarbon mixture illustrates the application of the robust controller. The dynamic simulation of this process is performed using EMSO - Environment Model Simulation and Optimization. Finally, a comparison with a linear MPC using a single model is presented.

  7. Stock assessment model outputs for ICCAT (International) managed species

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Includes outputs from the various models run in the evaluation of stock status for species managed by the International Commission for the Conservation of Atlantic...

  8. Chronic rejection in DLA identical dogs after orthotopic cardiac transplantation

    NARCIS (Netherlands)

    O.C.K.M. Penn

    1979-01-01

    textabstractThe justification for clinical cardiac transplantation is that it should solve end-stage cardiac disease when no other medical or surgical treatment is available (76). However, after cardiac transplantation the main barriers to long-term survival and complete rehabilitation include the

  9. Cardiac sodium channelopathies

    NARCIS (Netherlands)

    Amin, A.S.; Asghari-Roodsari, A.; Tan, H.L.

    2010-01-01

    Cardiac sodium channel are protein complexes that are expressed in the sarcolemma of cardiomyocytes to carry a large inward depolarizing current (I-Na) during phase 0 of the cardiac action potential. The importance of I-Na for normal cardiac electrical activity is reflected by the high incidence of

  10. Perioperative Rosuvastatin in Cardiac Surgery.

    Science.gov (United States)

    Zheng, Zhe; Jayaram, Raja; Jiang, Lixin; Emberson, Jonathan; Zhao, Yan; Li, Qi; Du, Juan; Guarguagli, Silvia; Hill, Michael; Chen, Zhengming; Collins, Rory; Casadei, Barbara

    2016-05-05

    Complications after cardiac surgery are common and lead to substantial increases in morbidity and mortality. Meta-analyses of small randomized trials have suggested that perioperative statin therapy can prevent some of these complications. We randomly assigned 1922 patients in sinus rhythm who were scheduled for elective cardiac surgery to receive perioperative rosuvastatin (at a dose of 20 mg daily) or placebo. The primary outcomes were postoperative atrial fibrillation within 5 days after surgery, as assessed by Holter electrocardiographic monitoring, and myocardial injury within 120 hours after surgery, as assessed by serial measurements of the cardiac troponin I concentration. Secondary outcomes included major in-hospital adverse events, duration of stay in the hospital and intensive care unit, left ventricular and renal function, and blood biomarkers. The concentrations of low-density lipoprotein cholesterol and C-reactive protein after surgery were lower in patients assigned to rosuvastatin than in those assigned to placebo (PSTICS ClinicalTrials.gov number, NCT01573143.).

  11. Exercise-induced cardiac remodeling.

    Science.gov (United States)

    Weiner, Rory B; Baggish, Aaron L

    2012-01-01

    Early investigations in the late 1890s and early 1900s documented cardiac enlargement in athletes with above-normal exercise capacity and no evidence of cardiovascular disease. Such findings have been reported for more than a century and continue to intrigue scientists and clinicians. It is well recognized that repetitive participation in vigorous physical exercise results in significant changes in myocardial structure and function. This process, termed exercise-induced cardiac remodeling (EICR), is characterized by structural cardiac changes including left ventricular hypertrophy with sport-specific geometry (eccentric vs concentric). Associated alterations in both systolic and diastolic functions are emerging as recognized components of EICR. The increasing popularity of recreational exercise and competitive athletics has led to a growing number of individuals exhibiting these findings in routine clinical practice. This review will provide an overview of EICR in athletes. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. HAEMODYNAMIC RESPONSE DURING EXERCISE TESTING IN PATIENTS WITH CORONARY ARTERY DISEASE UNDERGOING A CARDIAC REHABILITATION PROGRAMME

    Directory of Open Access Journals (Sweden)

    J. Siebert

    2011-09-01

    Full Text Available Haemodynamic monitoring during exercise testing is seldom used during cardiac rehabilitation. The aim was to evaluate haemodynamic changes using the cardiac impedance method during exercise testing in patients after percutaneous coronary interventions and coronary artery bypass grafting during cardiac rehabilitation. Thirty (25 M; 5 F patients were included in the programme. The group was divided according to ejection fraction (EF: low – below 50% normal – equal to or above 50%. The exercise test was performed simultaneously with a four-electrode impedance cardiogram before and after rehabilitation. ECG, blood pressure, thoracic impedance, first derivative dz/dt, stroke volume (SV and cardiac output were recorded. Contractility index (Heather index – HI and vascular peripheral resistance were calculated. The pattern of haemodynamic changes was normal in 24 patients. The deflection points for HI and SV trend patterns were observed among patients with low EF. The contractility index decreased 90 s before maximal exercise and after the next 30-60 s a deflection point was observed in SV curve trends. In 24 patients with normal EF the contractility index trends did not decrease and SV trends increased until the end of exercise or a deflection point was not noted. The deflection points of the contractility index and SV curves were observed before the clinical indications for exercise test termination appeared in patients with a low ejection fraction. Impedance cardiography may indicate the threshold of the workload during real-time exercise testing.

  13. Uncertainties in predicting solar panel power output

    Science.gov (United States)

    Anspaugh, B.

    1974-01-01

    The problem of calculating solar panel power output at launch and during a space mission is considered. The major sources of uncertainty and error in predicting the post launch electrical performance of the panel are considered. A general discussion of error analysis is given. Examples of uncertainty calculations are included. A general method of calculating the effect on the panel of various degrading environments is presented, with references supplied for specific methods. A technique for sizing a solar panel for a required mission power profile is developed.

  14. Conventional hemofiltration during cardiopulmonary bypass increases the serum lactate level in adult cardiac surgery

    Directory of Open Access Journals (Sweden)

    Rabie Soliman

    2016-01-01

    Full Text Available Objective: To evaluate the effect of hemofiltration during cardiopulmonary bypass on lactate level in adult patients who underwent cardiac surgery. Design: An observational study. Setting: Prince Sultan cardiac center, Riyadh, Saudi Arabia. Participants: The study included 283 patients classified into two groups: Hemofiltration group (n=138, hemofiltration was done during CPB. Control group (n = 145, patients without hemofiltration. Interventions: Hemofiltration during cardiopulmonary bypass. Measurements and Main Results: Monitors included hematocrit, lactate levels, mixed venous oxygen saturation, amount of fluid removal during hemofiltration and urine output. The lactate elevated in group H than group C (P < 0.05, and the PH showed metabolic acidosis in group H (P < 0.05. The mixed venous oxygen saturation decreased in group H than group C (P < 0.05. The number of transfused packed red blood cells was lower in group H than group C (P < 0.05. The hematocrit was higher in group H than group C (P < 0.05. The urine output was lower in group H than group C (P < 0.05. Conclusions: Hemofiltration during cardiopulmonary bypass leads to hemoconcentration, elevated lactate level and increased inotropic support. There are some recommendations for hemofiltration: First; Hemofiltration should be limited for patients with impaired renal function, positive fluid balance, reduced response to diuretics or prolonged bypass time more than 2 hours. Second; Minimal amount of fluids should be administered to maintain adequate cardiac output and reduction of priming volumes is preferable to maintain controlled hemodilution. Third; it should be done before weaning of or after cardiopulmonary bypass and not during the whole time of cardiopulmonary bypass.

  15. Expanded cardiac rehabilitation reduces cardiac events over five years.

    Science.gov (United States)

    Redfern, Julie

    2011-01-01

    In people with coronary artery disease, does an expanded cardiac rehabilitation program reduce cardiac deaths, myocardial infarctions, and hospital admissions due to cardiovascular disease? Randomised, controlled trial with intention-to-treat analysis. A University hospital in Sweden. People aged less than 75 years who had had a recent myocardial infarction or coronary artery bypass grafts were eligible to participate. Severe co-morbidities were exclusion criteria. Randomisation of 224 participants allocated 111 to undergo expanded cardiac rehabilitation and 113 to a control group. Both groups received standard cardiac rehabilitation, including physical training, education, group and individual counselling, and support to cease smoking. All participants received appropriate preventive medications. In addition, the intervention group received 20 group sessions of stress management, 3 sessions of cooking and diet counselling by a dietician, and a 5-day stay at a 'patient hotel' with several activities including physical training and information. Although other outcomes were reported at the conclusion of 1-year follow-up, the outcomes at the 5-year follow-up were rates of cardiac events: cardiovascular death, acute myocardial infarction, and readmission to a hospital due to other cardiovascular causes. All participants were followed up via national registers of health and mortality. During the 5-year follow-up, 53 (48%) participants in the expanded cardiac rehabilitation group and 68 (60%) participants in the control group had a cardiac event (hazard ratio 0.69, 95% CI 0.48 to 0.99). This difference was mainly due to only 12 (11%) participants having non-fatal myocardial infarctions in the treatment group versus 23 (20%) in the control group (hazard ratio 0.47, 95% CI 0.21 to 0.97). The number of hospitalisations and the number of days of hospitalisation were both significantly fewer in the treatment group than in the control group. Expanded cardiac rehabilitation

  16. Zebrafish heart as a model for human cardiac electrophysiology.

    Science.gov (United States)

    Vornanen, Matti; Hassinen, Minna

    2016-01-01

    The zebrafish (Danio rerio) has become a popular model for human cardiac diseases and pharmacology including cardiac arrhythmias and its electrophysiological basis. Notably, the phenotype of zebrafish cardiac action potential is similar to the human cardiac action potential in that both have a long plateau phase. Also the major inward and outward current systems are qualitatively similar in zebrafish and human hearts. However, there are also significant differences in ionic current composition between human and zebrafish hearts, and the molecular basis and pharmacological properties of human and zebrafish cardiac ionic currents differ in several ways. Cardiac ionic currents may be produced by non-orthologous genes in zebrafish and humans, and paralogous gene products of some ion channels are expressed in the zebrafish heart. More research on molecular basis of cardiac ion channels, and regulation and drug sensitivity of the cardiac ionic currents are needed to enable rational use of the zebrafish heart as an electrophysiological model for the human heart.

  17. Input/Output linearizing control of a nuclear reactor

    International Nuclear Information System (INIS)

    Perez C, V.

    1994-01-01

    The feedback linearization technique is an approach to nonlinear control design. The basic idea is to transform, by means of algebraic methods, the dynamics of a nonlinear control system into a full or partial linear system. As a result of this linearization process, the well known basic linear control techniques can be used to obtain some desired dynamic characteristics. When full linearization is achieved, the method is referred to as input-state linearization, whereas when partial linearization is achieved, the method is referred to as input-output linearization. We will deal with the latter. By means of input-output linearization, the dynamics of a nonlinear system can be decomposed into an external part (input-output), and an internal part (unobservable). Since the external part consists of a linear relationship among the output of the plant and the auxiliary control input mentioned above, it is easy to design such an auxiliary control input so that we get the output to behave in a predetermined way. Since the internal dynamics of the system is known, we can check its dynamics behavior on order of to ensure that the internal states are bounded. The linearization method described here can be applied to systems with one-input/one-output, as well as to systems with multiple-inputs/multiple-outputs. Typical control problems such as stabilization and reference path tracking can be solved using this technique. In this work, the input/output linearization theory is presented, as well as the problem of getting the output variable to track some desired trayectories. Further, the design of an input/output control system applied to the nonlinear model of a research nuclear reactor is included, along with the results obtained by computer simulation. (Author)

  18. Comparação dos efeitos da dobutamina e da milrinona sobre a hemodinâmica e o transporte de oxigênio em pacientes submetidos à cirurgia cardíaca com baixo débito cardíaco após indução anestésica Comparación de los efectos de la dobutamina y de la milrinona sobre la hemodinámica y el transporte de oxígeno en pacientes sometidos a cirugía cardiaca con bajo débito cardiaco después de inducción anestésica Comparison of the effects of dobutamine and milrinone on hemodynamic parameters and oxygen supply in patients undergoing cardiac surgery with low cardiac output after anesthetic induction

    Directory of Open Access Journals (Sweden)

    Maria José Carvalho Carmona

    2010-06-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: Diversas classes de fármacos inotrópicos, com efeitos hemodinâmicos diferentes, são utilizadas no tratamento do baixo débito cardíaco em pacientes com disfunção sistólica submetidos a procedimento cirúrgico cardíaco. O objetivo deste estudo foi comparar o efeito da dobutamina e da milrinona sobre a hemodinâmica e o transporte de oxigênio nessa população de pacientes. MÉTODO: Após aprovação do Comitê de Ética institucional e obtenção do consentimento escrito pós-informado, 20 pacientes submetidos à cirurgia cardíaca e com índice cardíaco JUSTIFICATIVA Y OBJETIVOS: Diversas clases de fármacos inotrópicos con efectos hemodinámicos diferentes, se usan en el tratamiento del bajo débito cardíaco en pacientes con disfunción sistólica sometidos al procedimiento quirúrgico cardíaco. El objetivo de este estudio, fue comparar el efecto de la dobutamina y de la milrinona sobre la hemodinámica y el transporte de oxígeno en esa población de pacientes. MÉTODO: Después de la aprobación del Comité de Ética institucional y de la obtención del consentimiento informado, 20 pacientes sometidos a la cirugía cardíaca y con índice cardíaco BACKGROUND AND OBJECTIVES: Several classes of inotropic drugs with different hemodynamic effects are used in the treatment of low cardiac output in patients with diastolic dysfunction undergoing cardiac surgery. The objective of the present study was to compare the effects of dobutamine and milrinone on hemodynamic parameters and oxygen supply in this population of patients. METHODS: After approval by the Ethics Committee of the institution and signing of the informed consent, 20 patients undergoing cardiac surgery with cardiac index < 2 L.min-1.m2 after anesthetic induction and place ment of a pulmonary artery catheter were randomly divided to receive dobutamine 5 µg.kg-1. min-1 (n = 10, or milrinone 0.5 µg.kg-1.min-1 (n = 10. Hemodynamic parameters were

  19. DOOp: DAOSPEC Output Optimizer pipeline

    Science.gov (United States)

    Cantat-Gaudin, Tristan; Donati, Paolo; Pancino, Elena; Bragaglia, Angela; Vallenari, Antonella; Friel, Eileen D.; Sordo, Rosanna; Jacobson, Heather R.; Magrini, Laura

    2017-09-01

    The DAOSPEC Output Optimizer pipeline (DOOp) runs efficient and convenient equivalent widths measurements in batches of hundreds of spectra. It uses a series of BASH scripts to work as a wrapper for the FORTRAN code DAOSPEC (ascl:1011.002) and uses IRAF (ascl:9911.002) to automatically fix some of the parameters that are usually set by hand when using DAOSPEC. This allows batch-processing of quantities of spectra that would be impossible to deal with by hand. DOOp was originally built for the large quantity of UVES and GIRAFFE spectra produced by the Gaia-ESO Survey, but just like DAOSPEC, it can be used on any high resolution and high signal-to-noise ratio spectrum binned on a linear wavelength scale.

  20. Fetal Primary Cardiac Tumors During Perinatal Period

    Directory of Open Access Journals (Sweden)

    Shi-Min Yuan

    2017-06-01

    Full Text Available Fetal primary cardiac tumors are rare, but they may cause complications, which are sometimes life threatening, including arrhythmias, hydrops fetalis, ventricular outflow/inflow obstruction, cardiac failure, and even sudden death. Among fetal primary cardiac tumors, rhabdomyomas are most common, followed by teratomas, fibromas, hemangiomas, and myxomas. Everolimus, a mammalian target of rapamycin inhibitor, has been reported to be an effective drug to cause tumor remission in three neonates with multiple cardiac rhabdomyomas. Neonatal cardiac surgery for the resection of primary cardiac tumors found by fetal echocardiography has been reported sporadically. However, open fetal surgery for pericardial teratoma resection, which was performed successfully via a fetal median sternotomy in one case report, could be a promising intervention to rescue these patients with large pericardial effusions. These recent achievements undoubtedly encourage further development in early management of fetal cardiac tumors. Owing to the rarity of fetal primary cardiac tumors, relevant information in terms of prenatal diagnosis, treatment, and prognosis remains to be clarified.

  1. Cardiac myofibrillar contractile properties during the progression from hypertension to decompensated heart failure.

    Science.gov (United States)

    Hanft, Laurin M; Emter, Craig A; McDonald, Kerry S

    2017-07-01

    Heart failure arises, in part, from a constellation of changes in cardiac myocytes including remodeling, energetics, Ca 2+ handling, and myofibrillar function. However, little is known about the changes in myofibrillar contractile properties during the progression from hypertension to decompensated heart failure. The aim of the present study was to provide a comprehensive assessment of myofibrillar functional properties from health to heart disease. A rodent model of uncontrolled hypertension was used to test the hypothesis that myocytes in compensated hearts exhibit increased force, higher rates of force development, faster loaded shortening, and greater power output; however, with progression to overt heart failure, we predicted marked depression in these contractile properties. We assessed contractile properties in skinned cardiac myocyte preparations from left ventricles of Wistar-Kyoto control rats and spontaneous hypertensive heart failure (SHHF) rats at ~3, ~12, and >20 mo of age to evaluate the time course of myofilament properties associated with normal aging processes compared with myofilaments from rats with a predisposition to heart failure. In control rats, the myofilament contractile properties were virtually unchanged throughout the aging process. Conversely, in SHHF rats, the rate of force development, loaded shortening velocity, and power all increased at ~12 mo and then significantly fell at the >20-mo time point, which coincided with a decrease in left ventricular fractional shortening. Furthermore, these changes occurred independent of changes in β-myosin heavy chain but were associated with depressed phosphorylation of myofibrillar proteins, and the fall in loaded shortening and peak power output corresponded with the onset of clinical signs of heart failure. NEW & NOTEWORTHY This novel study systematically examined the power-generating capacity of cardiac myofilaments during the progression from hypertension to heart disease. Previously

  2. Probabilistic Output Analysis by Program Manipulation

    DEFF Research Database (Denmark)

    Rosendahl, Mads; Kirkeby, Maja Hanne

    2015-01-01

    The aim of a probabilistic output analysis is to derive a probability distribution of possible output values for a program from a probability distribution of its input. We present a method for performing static output analysis, based on program transformation techniques. It generates a probabilit...

  3. Cardiac sympathetic nervous system imaging with (123)I-meta-iodobenzylguanidine: Perspectives from Japan and Europe

    NARCIS (Netherlands)

    Nakajima, K.; Scholte, A.; Nakata, T.; Dimitriu-Leen, A.C.; Chikamori, T.; Vitola, J.V.; Yoshinaga, K.

    2017-01-01

    Cardiac sympathetic nervous system dysfunction is closely associated with risk of serious cardiac events in patients with heart failure (HF), including HF progression, pump-failure death, and sudden cardiac death by lethal ventricular arrhythmia. For cardiac sympathetic nervous system imaging,

  4. Optical transducers with frequency output

    Science.gov (United States)

    Osadchuk, Oleksandr V.; Osadchuk, Volodymyr S.; Osadchuk, Iaroslav O.; Kolimoldayev, Maksat; Komada, Paweł; Mussabekov, Kanat

    2017-08-01

    In this work the characteristics research of microelectronic transducers of optical radiation with a frequency output signal on the basis of a hybrid integrated circuit consisting of a bipolar and a field-effect transistor with a Schottky barrier is presented. The connection of an external inductance to electrodes a collector - drain allows to implement the auto generating device. The frequency of the device generation depends on power of optical radiation falling on photosensing elements as a photoresistor, photodiode and photosensing transistors switched on in a circuit of the self-excited oscillator. The impedance on electrodes the collector - drain of bipolar and field transistors has capacitive reactive part and negative active resistance, which compensates power losses in a tuning circuit of the device. On the base of a nonlinear equivalent circuit of the transducer on an alternating current the analytical expressions of function of transformation and equation of sensitivity are obtained. The sensitivity of optical transducers lays in a range from 25 kHz/μWt/cm2 up to 150 kHz/μWt/cm2.

  5. Model output: fact or artefact?

    Science.gov (United States)

    Melsen, Lieke

    2015-04-01

    As a third-year PhD-student, I relatively recently entered the wonderful world of scientific Hydrology. A science that has many pillars that directly impact society, for example with the prediction of hydrological extremes (both floods and drought), climate change, applications in agriculture, nature conservation, drinking water supply, etcetera. Despite its demonstrable societal relevance, hydrology is often seen as a science between two stools. Like Klemeš (1986) stated: "By their academic background, hydrologists are foresters, geographers, electrical engineers, geologists, system analysts, physicists, mathematicians, botanists, and most often civil engineers." Sometimes it seems that the engineering genes are still present in current hydrological sciences, and this results in pragmatic rather than scientific approaches for some of the current problems and challenges we have in hydrology. Here, I refer to the uncertainty in hydrological modelling that is often neglected. For over thirty years, uncertainty in hydrological models has been extensively discussed and studied. But it is not difficult to find peer-reviewed articles in which it is implicitly assumed that model simulations represent the truth rather than a conceptualization of reality. For instance in trend studies, where data is extrapolated 100 years ahead. Of course one can use different forcing datasets to estimate the uncertainty of the input data, but how to prevent that the output is not a model artefact, caused by the model structure? Or how about impact studies, e.g. of a dam impacting river flow. Measurements are often available for the period after dam construction, so models are used to simulate river flow before dam construction. Both are compared in order to qualify the effect of the dam. But on what basis can we tell that the model tells us the truth? Model validation is common nowadays, but validation only (comparing observations with model output) is not sufficient to assume that a

  6. Comparative effects of glucose and water drinks on blood pressure and cardiac function in older subjects with and without postprandial hypotension.

    Science.gov (United States)

    Trahair, Laurence G; Rajendran, Sharmalar; Visvanathan, Renuka; Chapman, Matthew; Stadler, Daniel; Horowitz, Michael; Jones, Karen L

    2017-07-01

    Postprandial hypotension (PPH) occurs frequently and is thought to reflect an inadequate increase in cardiac output to compensate for the rise in splanchnic blood flow after a meal. Gastric distension by water attenuates the postprandial fall in blood pressure (BP). Cardiac hemodynamics (stroke volume (SV), cardiac output (CO), and global longitudinal strain (GLS)) have hitherto not been measured in PPH We sought to determine the comparative effects of water and glucose drinks on cardiac hemodynamics in healthy older subjects and individuals with PPH Eight healthy older subjects (age 71.0 ± 1.7 years) and eight subjects with PPH (age 75.5 ± 1.0 years) consumed a 300 mL drink of either water or 75 g glucose (including 150 mg 13 C-acetate) in randomized order. BP and heart rate (HR) were measured using an automatic device, SV, CO, and GLS by transthoracic echocardiography and gastric emptying by measurement of 13 CO 2 In both groups, glucose decreased systolic BP ( P  glucose and the pressor response to water were related ( R  = -0.75, P  glucose is associated with inadequate compensatory increases in CO and HR, whereas the pressor response to water ingestion is maintained and, possibly, exaggerated. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  7. Interferometric output coupling of ring optical oscillators.

    Science.gov (United States)

    Chaitanya Kumar, S; Esteban-Martin, A; Ebrahim-Zadeh, M

    2011-04-01

    We demonstrate the successful deployment of an antiresonant ring (ARR) interferometer within a ring optical resonator and its use for absolute optimization of output power. The integration of the ARR interferometer in a folded arm of the ring oscillator provides continuously variable output coupling over broad spectral range and under any operating conditions. We demonstrate the technique using a picosecond optical parametric oscillator (OPO), where we show continuously adjustable output coupling and optimization of the output power for different pump power conditions, from 3.5 W to 13.5 W. By operating the OPO under an optimized output coupling at 14 W of pump power, we obtain >5 W of extracted signal power, more than 2.6 times that with a ~5% conventional output coupler. We also show that the inclusion of the ARR interferometer has no detrimental effect on the spatial, temporal, and spectral characteristics of OPO output.

  8. Cardiac Rehabilitation Series: Canada

    Science.gov (United States)

    Grace, Sherry L.; Bennett, Stephanie; Ardern, Chris I.; Clark, Alexander

    2015-01-01

    Cardiovascular disease is among the leading causes of mortality and morbidity in Canada. Cardiac rehabilitation (CR) has a long robust history here, and there are established clinical practice guidelines. While the effectiveness of CR in the Canadian context is clear, only 34% of eligible patients participate, and strategies to increase access for under-represented groups (e.g., women, ethnic minority groups) are not yet universally applied. Identified CR barriers include lack of referral and physician recommendation, travel and distance, and low perceived need. Indeed there is now a national policy position recommending systematic inpatient referral to CR in Canada. Recent development of 30 CR Quality Indicators and the burgeoning national CR registry will enable further measurement and improvement of the quality of CR care in Canada. Finally, the Canadian Association of CR is one of the founding members of the International Council of Cardiovascular Prevention and Rehabilitation, to promote CR globally. PMID:24607018

  9. Cardiac sodium channelopathies.

    Science.gov (United States)

    Amin, Ahmad S; Asghari-Roodsari, Alaleh; Tan, Hanno L

    2010-07-01

    Cardiac sodium channel are protein complexes that are expressed in the sarcolemma of cardiomyocytes to carry a large inward depolarizing current (INa) during phase 0 of the cardiac action potential. The importance of INa for normal cardiac electrical activity is reflected by the high incidence of arrhythmias in cardiac sodium channelopathies, i.e., arrhythmogenic diseases in patients with mutations in SCN5A, the gene responsible for the pore-forming ion-conducting alpha-subunit, or in genes that encode the ancillary beta-subunits or regulatory proteins of the cardiac sodium channel. While clinical and genetic studies have laid the foundation for our understanding of cardiac sodium channelopathies by establishing links between arrhythmogenic diseases and mutations in genes that encode various subunits of the cardiac sodium channel, biophysical studies (particularly in heterologous expression systems and transgenic mouse models) have provided insights into the mechanisms by which INa dysfunction causes disease in such channelopathies. It is now recognized that mutations that increase INa delay cardiac repolarization, prolong action potential duration, and cause long QT syndrome, while mutations that reduce INa decrease cardiac excitability, reduce electrical conduction velocity, and induce Brugada syndrome, progressive cardiac conduction disease, sick sinus syndrome, or combinations thereof. Recently, mutation-induced INa dysfunction was also linked to dilated cardiomyopathy, atrial fibrillation, and sudden infant death syndrome. This review describes the structure and function of the cardiac sodium channel and its various subunits, summarizes major cardiac sodium channelopathies and the current knowledge concerning their genetic background and underlying molecular mechanisms, and discusses recent advances in the discovery of mutation-specific therapies in the management of these channelopathies.

  10. Hyperplastic Cardiac Sarcoma Recurrence

    Directory of Open Access Journals (Sweden)

    Masood A. Shariff

    2015-01-01

    Full Text Available Primary cardiac sarcomas are rare tumors with a median survival of 6–12 months. Data suggest that an aggressive multidisciplinary approach may improve patient outcome. We present the case of a male who underwent resection of cardiac sarcoma three times from the age of 32 to 34. This report discusses the malignant nature of cardiac sarcoma and the importance of postoperative multidisciplinary care.

  11. Giant cardiac myxoma.

    Science.gov (United States)

    Barlis, Peter; Lim, Eu Jin; Gow, Paul J; Seevanayagam, Siven; Calafiore, Paul; Chan, Robert K

    2007-10-01

    Although cardiac myxomas remain an uncommon group of malignancies, they are the most common form of primary cardiac tumour. Clinical presentations can be varied with local cardiac haemodynamic consequences, valvular insufficiency or even embolic phenomena. We present a case of a 46-year-old man with chronic abdominal pain and discuss a number of diagnostic challenges that were confronted up until a definitive diagnosis of cardiac myxoma was made. The resultant outcome was excellent with the patient achieving complete recovery from long term disabling symptoms.

  12. Cardiac event monitors

    Science.gov (United States)

    ... ECG) - ambulatory; Continuous electrocardiograms (EKGs); Holter monitors; Transtelephonic event monitors ... attached. You can carry or wear a cardiac event monitor up to 30 days. You carry the ...

  13. The 'icon' of output efficiency

    International Nuclear Information System (INIS)

    Bligh, L.N.; Evans, S.G.; Larcos, G.; Gruenewald, S.M.

    1999-01-01

    Full text: Output efficiency (OE) is a well-validated parameter used in the assessment of hydronephrosis. Current analysis on Microdelta appears to produce few low OE values and occasional inability to produce a result. We sought an OE program which gave a reliable response over the full range of values. The aims of this study were to determine: (1) whether OE results are comparable between two computer systems; (2) a normal range for OE on an ICON; (3) inter-observer reproducibility; and (4) the correlation between the two programs and the residual cortical activity ratio (RCA), an index which assesses tracer washout from the 20 min cortical activity/peak cortical activity. Accordingly, two blinded medical radiation scientists reviewed 41 kidneys (26 native, 15 transplant) and calculated OE for each kidney on the ICON and Microdelta computers The OE on the Microdelta and the ICON had good correspondence (r = 0.6%, SEE = 6.2). The extrapolated normal range for ICON OE was 69-92% (mean 80.9%). The inter-observer reproducibility on the ICON was excellent with a CV of 8.7%. ICON OE and RCA had a strong correlation (r = - 0.77, SEE = 0.09), compared with a weaker correlation for the Microdelta (r = 0.47, SEE = 0.13). Processing on the ICON was almost half that of the Microdelta at 4 min compared with 7 min. We conclude that OE generated by these computer programs has good correlation, an established normal range, excellent interobserver reproducibility, but differing correlation with RCA. The response of the ICON program to low ranges of OE is being investigated further

  14. Relationship between peak cardiac pumping capability and indices of cardio-respiratory fitness in healthy individuals.

    Science.gov (United States)

    Jakovljevic, Djordje G; Popadic-Gacesa, Jelena Z; Barak, Otto F; Nunan, David; Donovan, Gay; Trenell, Michael I; Grujic, Nikola G; Brodie, David A

    2012-09-01

    Cardiac power output (CPO) is a unique and direct measure of overall cardiac function (i.e. cardiac pumping capability) that integrates both flow- and pressure-generating capacities of the heart. The present study assessed the relationship between peak exercise CPO and selected indices of cardio-respiratory fitness. Thirty-seven healthy adults (23 men and 14 women) performed an incremental exercise test to volitional fatigue using the Bruce protocol with gas exchange and ventilatory measurements. Following a 40-min recovery, the subjects performed a constant maximum workload exercise test at or above 95% of maximal oxygen consumption. Cardiac output was measured using the exponential CO(2) rebreathing method. The CPO, expressed in W, was calculated as the product of the mean arterial blood pressure and cardiac output. At peak exercise, CPO was well correlated with cardiac output (r = 0·92, Pcardio-respiratory fitness such as oxygen consumption, anaerobic threshold, oxygen pulse, minute ventilation, carbon dioxide production and heart rate should not be used as surrogates for overall cardiac function and pumping capability of the heart. © 2012 The Authors Clinical Physiology and Functional Imaging © 2012 Scandinavian Society of Clinical Physiology and Nuclear Medicine.

  15. FEL system with homogeneous average output

    Energy Technology Data Exchange (ETDEWEB)

    Douglas, David R.; Legg, Robert; Whitney, R. Roy; Neil, George; Powers, Thomas Joseph

    2018-01-16

    A method of varying the output of a free electron laser (FEL) on very short time scales to produce a slightly broader, but smooth, time-averaged wavelength spectrum. The method includes injecting into an accelerator a sequence of bunch trains at phase offsets from crest. Accelerating the particles to full energy to result in distinct and independently controlled, by the choice of phase offset, phase-energy correlations or chirps on each bunch train. The earlier trains will be more strongly chirped, the later trains less chirped. For an energy recovered linac (ERL), the beam may be recirculated using a transport system with linear and nonlinear momentum compactions M.sub.56, which are selected to compress all three bunch trains at the FEL with higher order terms managed.

  16. Pediatric cardiac emergencies: Children are not small adults

    Directory of Open Access Journals (Sweden)

    Frazier Aisha

    2011-01-01

    Full Text Available Compared with adults, cardiac emergencies are infrequent in children and clinical presentation is often quite variable. In adults, cardiac emergencies are most commonly related to complications of coronary artery disease; however, in pediatric cases, the coronaries are only rarely the underlying problem. Pediatric cardiac emergencies comprise a range of pathology including but not limited to undiagnosed congenital heart disease in the infant; complications of palliated congenital heart disease in children; arrhythmias related to underlying cardiac pathology in the teenager and acquired heart disease. The emergency room physician and pediatric intensivist will usually be the first and second lines of care for pediatric cardiac emergencies and thus it is imperative that they have knowledge of the diverse presentations of cardiac disease in order to increase the likelihood of delivering early appropriate therapy and referral. The objective of this review is to outline cardiac emergencies in the pediatric population and contrast the presentation with adults.

  17. [Penetrating cardiac injury in blunt trauma: a case report].

    Science.gov (United States)

    Dereli, Yüksel; Öncel, Murat

    2015-05-01

    Cardiac injuries may rarely be observed due to blunt thoracic traumas. Cardiac injury often creates a life-threatening condition requiring urgent surgical intervention, and follow-up of these patients should be carefully carried out in the perioperative period. These injuries depend on various factors including clinical presentation, type of injury, the time that passes until the patient reaches the hospital, bleeding, cardiac tamponade, or additional injuries. This article aimed to report a case who suffered penetrating cardiac injury in blunt thoracic trauma. Evaluated in the emergency department due to a motor vehicle accident, the 61-year-old male patient's chest x-ray revealed pulmonary contusion, rib fractures and cardiac tamponade. The patient was operated emergently. Right atrial injury was observed in the operation. The cardiac injury was repaired with primary suture technique. Cardiac injury in patients with blunt thoracic trauma is likely to be observed. In these patients, careful physical examination, early diagnosis, and treatment are very important.

  18. Cardiac Injuries: A Review of Multidetector Computed Tomography Findings

    Science.gov (United States)

    Baxi, Ameya Jagdish; Restrepo, Carlos; Mumbower, Amy; McCarthy, Michael; Rashmi, Katre

    2015-01-01

    Trauma is the leading cause of death in United States in the younger population. Cardiac trauma is common following blunt chest injuries and is associated with high morbidity and mortality. This study discusses various multidetector computed tomography (MDCT) findings of cardiac trauma. Cardiac injuries are broadly categorized into the most commonly occurring blunt cardiac injury and the less commonly occurring penetrating injury. Signs and symptoms of cardiac injury can be masked by the associated injuries. Each imaging modality including chest radiographs, echocardiography, magnetic resonance imaging and MDCT has role in evaluating these patients. However, MDCT is noninvasive; universally available and has a high spatial, contrast, and temporal resolution. It is a one stop shop to diagnose and evaluate complications of cardiac injury. MDCT is an imaging modality of choice to evaluate patients with cardiac injuries especially the injuries capable of causing hemodynamic instability. PMID:26839855

  19. Theoretical analysis of magnetic sensor output voltage

    International Nuclear Information System (INIS)

    Liu Haishun; Dun Chaochao; Dou Linming; Yang Weiming

    2011-01-01

    The output voltage is an important parameter to determine the stress state in magnetic stress measurement, the relationship between the output voltage and the difference in the principal stresses was investigated by a comprehensive application of magnetic circuit theory, magnetization theory, stress analysis as well as the law of electromagnetic induction, and a corresponding quantitative equation was derived. It is drawn that the output voltage is proportional to the difference in the principal stresses, and related to the angle between the principal stress and the direction of the sensor. This investigation provides a theoretical basis for the principle stresses measurement by output voltage. - Research highlights: → A comprehensive investigation of magnetic stress signal. → Derived a quantitative equation about output voltage and the principal stresses. → The output voltage is proportional to the difference of the principal stresses. → Provide a theoretical basis for the principle stresses measurement.

  20. Output order in immediate serial recall.

    Science.gov (United States)

    Tan, Lydia; Ward, Geoff

    2007-07-01

    In two experiments, we examined the effect of output order in immediate serial recall (ISR). In Experiment 1, three groups of participants saw lists of eight words and wrote down the words in the rows corresponding to their serial positions in an eight-row response grid. One group was precued to respond in forward order, a second group was precued to respond in any order, and a third group was postcued for response order. There were significant effects of output order, but not of cue type. Relative to the forward output order, the free output order led to enhanced recency and diminished primacy, with superior performance for words output early in recall. These results were replicated in Experiment 2 using six-item lists, which further suggests that output order plays an important role in the primacy effect in ISR and that the recency items are most highly accessible at recall.

  1. Safety in cardiac surgery

    NARCIS (Netherlands)

    Siregar, S.

    2013-01-01

    The monitoring of safety in cardiac surgery is a complex process, which involves many clinical, practical, methodological and statistical issues. The objective of this thesis was to measure and to compare safety in cardiac surgery in The Netherlands using the Netherlands Association for

  2. [Advances in cardiac pacing].

    Science.gov (United States)

    de Carranza, María-José Sancho-Tello; Fidalgo-Andrés, María Luisa; Ferrer, José Martínez; Mateas, Francisco Ruiz

    2012-01-01

    This article contains a review of the current status of remote monitoring and follow-up involving cardiac pacing devices and of the latest developments in cardiac resynchronization therapy. In addition, the most important articles published in the last year are discussed. Copyright © 2012 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

  3. Cardiac Catheterization (For Kids)

    Science.gov (United States)

    ... First Aid & Safety Doctors & Hospitals Videos Recipes for Kids Kids site Sitio para niños How the Body Works ... Educators Search English Español Cardiac Catheterization KidsHealth / For Kids / Cardiac Catheterization What's in this article? What Is ...

  4. Cardiac surgery in the parturient.

    Science.gov (United States)

    Chandrasekhar, Shobana; Cook, Christopher R; Collard, Charles D

    2009-03-01

    Heart disease is the primary cause of nonobstetric mortality in pregnancy, occurring in 1%-3% of pregnancies and accounting for 10%-15% of maternal deaths. Congenital heart disease has become more prevalent in women of childbearing age, representing an increasing percentage (up to 75%) of heart disease in pregnancy. Untreated maternal heart disease also places the fetus at risk. Independent predictors of neonatal complications include a maternal New York Heart Association heart failure classification >2, anticoagulation use during pregnancy, smoking, multiple gestation, and left heart obstruction. Because cardiac surgical morbidity and mortality in the parturient is higher than nonpregnant patients, most parturients with cardiac disease are first managed medically, with cardiac surgery being reserved when medical management fails. Risk factors for maternal mortality during cardiac surgery include the use of vasoactive drugs, age, type of surgery, reoperation, and maternal functional class. Risk factors for fetal mortality include maternal age >35 yr, functional class, reoperation, emergency surgery, type of myocardial protection, and anoxic time. Nonetheless, acceptable maternal and fetal perioperative mortality rates may be achieved through such measures as early preoperative detection of maternal cardiovascular decompensation, use of fetal monitoring, delivery of a viable fetus before the operation and scheduling surgery on an elective basis during the second trimester. Additionally, fetal morbidity may be reduced during cardiopulmonary bypass by optimizing maternal oxygen-carrying capacity and uterine blood flow. Current maternal bypass recommendations include: 1) maintaining the pump flow rate >2.5 L x min(-1) x m(-2) and perfusion pressure >70 mm Hg; 2) maintaining the hematocrit > 28%; 3) using normothermic perfusion when feasible; 4) using pulsatile flow; and 5) using alpha-stat pH management.

  5. Cardiac image segmentation for contrast agent videodensitometry.

    Science.gov (United States)

    Mischi, Massimo; Kalker, Antonius A C M; Korsten, Hendrikus H M

    2005-02-01

    Indicator dilution techniques are widely used in the intensive care unit and operating room for cardiac parameter measurements. However, the invasiveness of current techniques represents a limitation for their clinical use. The development of stable ultrasound contrast agents allows new applications of the indicator dilution method. Ultrasound contrast agent dilutions permit an echographic noninvasive measurement of cardiac output, ejection fraction, and blood volumes. The indicator dilution curves are measured by videodensitometry of specific regions of interest and processed for the cardiac parameter assessment. Therefore, the major indicator dilution imaging issue is the detection of proper contrast videodensitometry regions that maximize the signal-to-noise ratio of the measured indicator dilution curves. This paper presents an automatic contour detection algorithm for indicator dilution videodensitometry. The algorithm consists of a radial filter combined with an outlier correction. It maximizes the region of interest by excluding cardiac structures that act as interference to the videodensitometric analysis. It is fast, projection independent, and allows the simultaneous detection of multiple contours in real time. The system is compared to manual contour definition on both echographic and magnetic resonance images.

  6. Does trade drive global output growth?

    OpenAIRE

    Leon Podkaminer

    2014-01-01

    Conventional econometric analysis suggests that there has been a longer-term relationship between nominal world output and nominal world exports. The analysis says something about the rules governing adjustments in world output and exports. It appears that GDP plays the first fiddle. Rising world output seems to have pushed up world exports. But rising world exports do not seem to have resulted in positive changes in global GDP. The global growth slowdown, observed since the early 1970s, may ...

  7. The optimal hemodynamics management of post-cardiac arrest shock.

    Science.gov (United States)

    Pellis, Tommaso; Sanfilippo, Filippo; Ristagno, Giuseppe

    2015-12-01

    Patients resuscitated from cardiac arrest develop a pathophysiological state named "post-cardiac arrest syndrome." Post-resuscitation myocardial dysfunction is a common feature of this syndrome, and many patients eventually die from cardiovascular failure. Cardiogenic shock accounts for most deaths in the first 3 days, when post-resuscitation myocardial dysfunction peaks. Thus, identification and treatment of cardiovascular failure is one of the key therapeutic goals during hospitalization of post-cardiac arrest patients. Patients with hemodynamic instability may require advanced cardiac output monitoring. Inotropes and vasopressors should be considered if hemodynamic goals are not achieved despite optimized preload. If these measures fail to restore adequate organ perfusion, a mechanical circulatory assistance device may be considered. Adequate organ perfusion should be ensured in the absence of definitive data on the optimal target pressure goals. Hemodynamic goals should also take into account targeted temperature management and its effect on the cardiovascular function. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Sudden cardiac death

    Directory of Open Access Journals (Sweden)

    Neeraj Parakh

    2015-01-01

    Full Text Available Sudden cardiac death is one of the most common cause of mortality worldwide. Despite significant advances in the medical science, there is little improvement in the sudden cardiac death related mortality. Coronary artery disease is the most common etiology behind sudden cardiac death, in the above 40 years population. Even in the apparently healthy population, there is a small percentage of patients dying from sudden cardiac death. Given the large denominator, this small percentage contributes to the largest burden of sudden cardiac death. Identification of this at risk group among the apparently healthy individual is a great challenge for the medical fraternity. This article looks into the causes and methods of preventing SCD and at some of the Indian data. Details of Brugada syndrome, Long QT syndrome, Genetics of SCD are discussed. Recent guidelines on many of these causes are summarised.

  9. Exercise efficiency of low power output cycling.

    Science.gov (United States)

    Reger, M; Peterman, J E; Kram, R; Byrnes, W C

    2013-12-01

    Exercise efficiency at low power outputs, energetically comparable to daily living activities, can be influenced by homeostatic perturbations (e.g., weight gain/loss). However, an appropriate efficiency calculation for low power outputs used in these studies has not been determined. Fifteen active subjects (seven females, eight males) performed 14, 5-min cycling trials: two types of seated rest (cranks vertical and horizontal), passive (motor-driven) cycling, no-chain cycling, no-load cycling, cycling at low (10, 20, 30, 40 W), and moderate (50, 60, 80, 100, 120 W) power outputs. Mean delta efficiency was 57% for low power outputs compared to 41.3% for moderate power outputs. Means for gross (3.6%) and net (5.7%) efficiencies were low at the lowest power output. At low power outputs, delta and work efficiency values exceeded theoretical values. In conclusion, at low power outputs, none of the common exercise efficiency calculations gave values comparable to theoretical muscle efficiency. However, gross efficiency and the slope and intercept of the metabolic power vs mechanical power output regression provide insights that are still valuable when studying homeostatic perturbations. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Output filters for AC adjustable speed drives

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Hanigovszki, Norbert; Landkildehus, Jorn, Jorn

    2007-01-01

    -phase applications the occurrence of common-mode (CM) voltage is inherent due to asymmetrical output pulses [1]. Consequently, several secondary effects arise at the inverter's output: high-frequency conducted and radiated emissions, leakage current, motor insulation stress due to wave reflection [2], bearing stress...... due to bearing currents, acoustic switching noise. Depending on the specific application, the mitigation of some of these effects (or all) might be necessary. The common solution for mitigating the secondary effects at the output of PWM-VSI is the use of output filters [3],[5],[6]. Several types...

  11. Successful use of levosimendan as a primary inotrope in pediatric cardiac surgery: An observational study in 110 patients

    Directory of Open Access Journals (Sweden)

    Reena Khantwal Joshi

    2016-01-01

    Conclusions: Levosimendan-based inotropic regime offers optimized cardiac output with a well-controlled heart rate and a low incidence of arrhythmias in patients undergoing all categories of congenital heart surgeries.

  12. Effect of cardiac function on aortic peak time and peak enhancement during coronary CT angiography

    International Nuclear Information System (INIS)

    Sakai, Shuji; Yabuuchi, Hidetake; Chishaki, Akiko; Okafuji, Takashi; Matsuo, Yoshio; Kamitani, Takeshi; Setoguchi, Taro; Honda, Hiroshi

    2010-01-01

    Purpose: To examine the manner in which cardiac function affects the magnitude and timing of aortic contrast enhancement during coronary CT angiography (CTA). Materials and methods: Twenty-nine patients (21 men, 8 women; mean age, 64.4 ± 13.4 years; mean weight, 59.4 ± 10.3 kg) underwent measurement of cardiac output within 2 weeks of coronary CTA. The cardiac output of each patient was measured by the thermodilution technique and the cardiac index was calculated from the body surface area. During coronary CTA, attenuation of the descending aorta was measured at the workstation every 3 s. The aortic peak time (APT) and aortic peak enhancement (APE) of each patient were calculated. Pearson's correlation coefficient analysis was used to investigate the relationships between the cardiac output or cardiac index and APT or APE. Furthermore, the relationship between patient factors or parameters on test bolus injection and APT or APE was also evaluated. Results: The range of cardiac output, cardiac index, APT, and APE was 1.55-10.46 L/min (mean: 4.77 ± 2.13), 1.11-5.30 L/(min-m 2 ) (mean: 3.28 ± 1.08), 25-51 s (mean: 38.3 ± 7.5), and 273.1-598.1 HU (mean: 390.4 ± 72.1), respectively. With an increase in the cardiac index, both APT (r = -0.698, p < 0.0001) and APE (r = -0.573, p = 0.0009) decreased. There were significant correlations between the patient body weight and APT and APE with the test bolus injection, and with APT and APE during coronary CTA. Conclusion: The APT and APE during coronary CTA are closely related to cardiac function.

  13. Air medical transport of cardiac patients.

    Science.gov (United States)

    Essebag, Vidal; Halabi, Abdul R; Churchill-Smith, Michael; Lutchmedial, Sohrab

    2003-11-01

    The air medical transport of cardiac patients is a rapidly expanding practice. For various medical, social, and economic indications, patients are being flown longer distances at commercial altitudes, including international and intercontinental flights. There are data supporting the use of short-distance helicopter flights early in the course of a cardiac event for patients needing emergent transfer for percutaneous coronary intervention or aortocoronary bypass. When considering elective long-distance air medical transport of cardiac patients for social or economic reasons, it is necessary to weigh the benefits against the potential risks of flight. A few recent studies suggest that long-distance air medical transport is safe under certain circumstances. Current guidelines for air travel after myocardial infarction do not address the use of medical escorts or air ambulances equipped with intensive care facilities. Further research using larger prospective studies is needed to better define criteria for safe long-distance air medical transport of cardiac patients.

  14. Cardiac myxoma in pregnancy: a comprehensive review.

    Science.gov (United States)

    Yuan, Shi-Min

    2015-01-01

    Cardiac myxoma in pregnancy is rare and the clinical characteristics of this entity have been insufficiently elucidated. This article aims to describe the treatment options and the risk factors responsible for the maternal and feto-neonatal prognoses. A comprehensive search of the literature of cardiac myxoma in pregnancy was conducted and 44 articles with 51 patients were included in the present review. Transthoracic echocardiography was the most common diagnostic tool for the diagnosis of cardiac myxoma during pregnancy. Cardiac myxoma resection was performed in 95.9% (47/49); while no surgical resection was performed in 4.1% (2/49) patients (P=0.000). More patients had an isolated cardiac myxoma resection in comparison to those with a concurrent or staged additional cardiac operation [87.2% (41/47) vs. 12.8% (6/47), P=0.000]. A voluntary termination of the pregnancy was done in 7 (13.7%) cases. In the remaining 31 (60.8%) pregnant patients, cesarean section was the most common delivery mode representing 61.3% and vaginal delivery was more common accounting for 19.4%. Cardiac surgery was performed in the first, second and third trimester in 5 (13.9%), 14 (38.9%) and 17 (47.2%) patients, respectively. No patients died. In the delivery group, 20 (76.9%) neonates were event-free survivals, 4 (15.4%) were complicated and 2 (7.7%) died. Neonatal prognoses did not differ between the delivery modes, treatment options, timing of cardiac surgery and sequence of cardiac myxoma resection in relation to delivery. The diagnosis of cardiac myxoma in pregnancy is important. Surgical treatment of cardiac myxoma in the pregnant patients has brought about favorable maternal and feto-neonatal outcomes in the delivery group, which might be attributable to the shorter operation duration and non-emergency nature of the surgical intervention. Proper timing of cardiac surgery and improved cardiopulmonary bypass conditions may result in even better maternal and feto-neonatal survivals.

  15. Cardiac myxoma in pregnancy: a comprehensive review

    Directory of Open Access Journals (Sweden)

    Shi-Min Yuan

    2015-09-01

    Full Text Available AbstractObjective:Cardiac myxoma in pregnancy is rare and the clinical characteristics of this entity have been insufficiently elucidated. This article aims to describe the treatment options and the risk factors responsible for the maternal and feto-neonatal prognoses.Methods:A comprehensive search of the literature of cardiac myxoma in pregnancy was conducted and 44 articles with 51 patients were included in the present review.Results:Transthoracic echocardiography was the most common diagnostic tool for the diagnosis of cardiac myxoma during pregnancy. Cardiac myxoma resection was performed in 95.9% (47/49; while no surgical resection was performed in 4.1% (2/49 patients (P=0.000. More patients had an isolated cardiac myxoma resection in comparison to those with a concurrent or staged additional cardiac operation [87.2% (41/47 vs. 12.8% (6/47, P=0.000]. A voluntary termination of the pregnancy was done in 7 (13.7% cases. In the remaining 31 (60.8% pregnant patients, cesarean section was the most common delivery mode representing 61.3% and vaginal delivery was more common accounting for 19.4%. Cardiac surgery was performed in the first, second and third trimester in 5 (13.9%, 14 (38.9% and 17 (47.2% patients, respectively. No patients died. In the delivery group, 20 (76.9% neonates were event-free survivals, 4 (15.4% were complicated and 2 (7.7% died. Neonatal prognoses did not differ between the delivery modes, treatment options, timing of cardiac surgery and sequence of cardiac myxoma resection in relation to delivery.Conclusion:The diagnosis of cardiac myxoma in pregnancy is important. Surgical treatment of cardiac myxoma in the pregnant patients has brought about favorable maternal and feto-neonatal outcomes in the delivery group, which might be attributable to the shorter operation duration and non-emergency nature of the surgical intervention. Proper timing of cardiac surgery and improved cardiopulmonary bypass conditions may result in

  16. Cardiac function of the naked mole-rat: ecophysiological responses to working underground.

    Science.gov (United States)

    Grimes, Kelly M; Voorhees, Andrew; Chiao, Ying Ann; Han, Hai-Chao; Lindsey, Merry L; Buffenstein, Rochelle

    2014-03-01

    The naked mole-rat (NMR) is a strictly subterranean rodent with a low resting metabolic rate. Nevertheless, it can greatly increase its metabolic activity to meet the high energetic demands associated with digging through compacted soils in its xeric natural habitat where food is patchily distributed. We hypothesized that the NMR heart would naturally have low basal function and exhibit a large cardiac reserve, thereby mirroring the species' low basal metabolism and large metabolic scope. Echocardiography showed that young (2-4 yr old) healthy NMRs have low fractional shortening (28 ± 2%), ejection fraction (43 ± 2%), and cardiac output (6.5 ± 0.4 ml/min), indicating low basal cardiac function. Histology revealed large NMR cardiomyocyte cross-sectional area (216 ± 10 μm(2)) and cardiac collagen deposition of 2.2 ± 0.4%. Neither of these histomorphometric traits was considered pathological, since biaxial tensile testing showed no increase in passive ventricular stiffness. NMR cardiomyocyte fibers showed a low degree of rotation, contributing to the observed low NMR cardiac contractility. Interestingly, when the exercise mimetic dobutamine (3 μg/g ip) was administered, NMRs showed pronounced increases in fractional shortening, ejection fraction, cardiac output, and stroke volume, indicating an increased cardiac reserve. The relatively low basal cardiac function and enhanced cardiac reserve of NMRs are likely to be ecophysiological adaptations to life in an energetically taxing environment.

  17. Imaging for cardiac electrophysiology

    Directory of Open Access Journals (Sweden)

    Benoit Desjardins

    2016-11-01

    Full Text Available Clinical cardiac electrophysiology is the study of the origin and treatment of arrhythmia. There has been considerable recent development in this field, where imaging has had a transformational impact. In this invited review, we offer a global overview of the most important developments in the use of imaging in cardiac electrophysiology. We first describe the radiological imaging modalities involved in cardiac electrophysiology, to assess cardiac anatomy, function and scar. We then introduce an imaging modality with which readers are probably unfamiliar (electroanatomical mapping [EAM], but which is routinely used by electrophysiologists to plan and guide cardiac mapping and cardiac ablation therapy by catheter, a therapy which can reduce or even cure arrhythmia. We identify the limitations of EAM and describe how radiological imaging modalities can complement this technique. We then describe and illustrate how imaging has helped the diagnosis of arrhythmogenic conditions, and how imaging is used to plan and guide clinical cardiac electrophysiologic procedures and assess their results and complications. We focus on the two most common arrhythmias for which imaging has the greatest impact: atrial fibrillation and ventricular tachycardia.

  18. Cardiac tumors: echo assessment

    Directory of Open Access Journals (Sweden)

    Rekha Mankad MD

    2016-12-01

    Full Text Available Cardiac tumors are exceedingly rare (0.001–0.03% in most autopsy series. They can be present anywhere within the heart and can be attached to any surface or be embedded in the myocardium or pericardial space. Signs and symptoms are nonspecific and highly variable related to the localization, size and composition of the cardiac mass. Echocardiography, typically performed for another indication, may be the first imaging modality alerting the clinician to the presence of a cardiac mass. Although echocardiography cannot give the histopathology, certain imaging features and adjunctive tools such as contrast imaging may aid in the differential diagnosis as do the adjunctive clinical data and the following principles: (1 thrombus or vegetations are the most likely etiology, (2 cardiac tumors are mostly secondary and (3 primary cardiac tumors are mostly benign. Although the finding of a cardiac mass on echocardiography may generate confusion, a stepwise approach may serve well practically. Herein, we will review such an approach and the role of echocardiography in the assessment of cardiac masses.

  19. Endogenous Natural Complement Inhibitor Regulates Cardiac Development

    DEFF Research Database (Denmark)

    Mortensen, Simon A; Skov, Louise L; Kjaer-Sorensen, Kasper

    2017-01-01

    mechanisms during fetal development and adult homeostasis. In this article, we describe the function of an endogenous complement inhibitor, mannan-binding lectin (MBL)-associated protein (MAp)44, in regulating the composition of a serine protease-pattern recognition receptor complex, MBL-associated serine...... of MAp44 caused impaired cardiogenesis, lowered heart rate, and decreased cardiac output. These defects were associated with aberrant neural crest cell behavior. We found that MAp44 competed with MASP-3 for pattern recognition molecule interaction, and knockdown of endogenous MAp44 expression could...

  20. Massage therapy after cardiac surgery.

    Science.gov (United States)

    Wang, Amy T; Sundt, Thoralf M; Cutshall, Susanne M; Bauer, Brent A

    2010-01-01

    Cardiac surgery presents a life-saving and life-enhancing opportunity to hundreds of thousands of patients each year in the United States. However, many patients face significant challenges during the postoperative period, including pain, anxiety, and tension. Mounting evidence demonstrates that such challenges can impair immune function and slow wound healing, in addition to causing suffering for the patient. Finding new approaches to mitigate these challenges is necessary if patients are to experience the full benefits of surgery. Massage therapy is a therapy that has significant evidence to support its role in meeting these needs. This paper looks at the data surrounding the use of massage therapy in cardiac surgery patients, with a special focus on the experience at Mayo Clinic. Copyright © 2010 Elsevier Inc. All rights reserved.

  1. Early-Transition Output Decline Revisited

    Directory of Open Access Journals (Sweden)

    Crt Kostevc

    2016-05-01

    Full Text Available In this paper we revisit the issue of aggregate output decline that took place in the early transition period. We propose an alternative explanation of output decline that is applicable to Central- and Eastern-European countries. In the first part of the paper we develop a simple dynamic general equilibrium model that builds on work by Gomulka and Lane (2001. In particular, we consider price liberalization, interpreted as elimination of distortionary taxation, as a trigger of the output decline. We show that price liberalization in interaction with heterogeneous adjustment costs and non-employment benefits lead to aggregate output decline and surge in wage inequality. While these patterns are consistent with actual dynamics in CEE countries, this model cannot generate output decline in all sectors. Instead sectors that were initially taxed even exhibit output growth. Thus, in the second part we consider an alternative general equilibrium model with only one production sector and two types of labor and distortion in a form of wage compression during the socialist era. The trigger for labor mobility and consequently output decline is wage liberalization. Assuming heterogeneity of workers in terms of adjustment costs and non-employment benefits can explain output decline in all industries.

  2. Exact nonradial input, output, and productivity measurement

    OpenAIRE

    Robert G. Chambers

    2002-01-01

    The use of measures originally suggested by Bennet, Bowley, and Hicks in the context of cost of living, welfare, and consumer surplus measurement to measure inputs, outputs, and productivity is examined. Suitably normalized versions of the Bennet-Bowley measures are shown to be exact and superlative measures of input, output, and productivity indicators.

  3. DIST/AVC Out-Put Definition.

    Science.gov (United States)

    Wilkinson, Gene L.

    The first stage of development of a management information system for DIST/AVC (Division of Instructional Technology/Audio-Visual Center) is the definition of out-put units. Some constraints on the definition of output units are: 1) they should reflect goals of the organization, 2) they should reflect organizational structure and procedures, and…

  4. The Blue Coma: The Role of Methylene Blue in Unexplained Coma After Cardiac Surgery.

    Science.gov (United States)

    Martino, Enrico Antonio; Winterton, Dario; Nardelli, Pasquale; Pasin, Laura; Calabrò, Maria Grazia; Bove, Tiziana; Fanelli, Giovanna; Zangrillo, Alberto; Landoni, Giovanni

    2016-04-01

    Methylene blue commonly is used as a dye or an antidote, but also can be used off label as a vasopressor. Serotonin toxicity is a potentially lethal and often misdiagnosed condition that can result from drug interaction. Mild serotonin toxicity previously was reported in settings in which methylene blue was used as a dye. The authors report 3 cases of life-threatening serotonin toxicity in patients undergoing chronic selective serotonin reuptake inhibitor (SSRI) therapy who also underwent cardiac surgery and received methylene blue to treat vasoplegic syndrome. An observational study. A cardiothoracic intensive care unit (ICU) in a teaching hospital. Three patients who received methylene blue after cardiac surgery, later discovered to be undergoing chronic SSRI therapy. None. All 3 patients received high doses of fentanyl during general anesthesia. They all developed vasoplegic syndrome and consequently were given methylene blue in the ICU. All 3 patients developed serotonin toxicity, including coma, after this administration and diagnostic tests were negative for acute intracranial pathology. Coma lasted between 1 and 5 days. Two patients were discharged from the ICU shortly after awakening, whereas the third patient experienced a complicated postoperative course for concomitant refractory low-cardiac-output syndrome. Patients undergoing chronic SSRI therapy should not be administered methylene blue to treat vasoplegic syndrome. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. The left ventricle as a mechanical engine: from Leonardo da Vinci to the echocardiographic assessment of peak power output-to-left ventricular mass.

    Science.gov (United States)

    Dini, Frank L; Guarini, Giacinta; Ballo, Piercarlo; Carluccio, Erberto; Maiello, Maria; Capozza, Paola; Innelli, Pasquale; Rosa, Gian M; Palmiero, Pasquale; Galderisi, Maurizio; Razzolini, Renato; Nodari, Savina

    2013-03-01

    The interpretation of the heart as a mechanical engine dates back to the teachings of Leonardo da Vinci, who was the first to apply the laws of mechanics to the function of the heart. Similar to any mechanical engine, whose performance is proportional to the power generated with respect to weight, the left ventricle can be viewed as a power generator whose performance can be related to left ventricular mass. Stress echocardiography may provide valuable information on the relationship between cardiac performance and recruited left ventricular mass that may be used in distinguishing between adaptive and maladaptive left ventricular remodeling. Peak power output-to-mass, obtained during exercise or pharmacological stress echocardiography, is a measure that reflects the number of watts that are developed by 100 g of left ventricular mass under maximal stimulation. Power output-to-mass may be calculated as left ventricular power output per 100 g of left ventricular mass: 100× left ventricular power output divided by left ventricular mass (W/100 g). A simplified formula to calculate power output-to-mass is as follows: 0.222 × cardiac output (l/min) × mean blood pressure (mmHg)/left ventricular mass (g). When the integrity of myocardial structure is compromised, a mismatch becomes apparent between maximal cardiac power output and left ventricular mass; when this occurs, a reduction of the peak power output-to-mass index is observed.

  6. Administration of granulocyte-colony stimulating factor accompanied with a balanced diet improves cardiac function alterations induced by high fat diet in mice.

    Science.gov (United States)

    Daltro, Pâmela Santana; Alves, Paula Santana; Castro, Murilo Fagundes; Azevedo, Carine M; Vasconcelos, Juliana Fraga; Allahdadi, Kyan James; de Freitas, Luiz Antônio Rodrigues; de Freitas Souza, Bruno Solano; Dos Santos, Ricardo Ribeiro; Soares, Milena Botelho Pereira; Macambira, Simone Garcia

    2015-12-03

    High fat diet (HFD) is a major contributor to the development of obesity and cardiovascular diseases due to the induction of cardiac structural and hemodynamic abnormalities. We used a model of diabetic cardiomyopathy in C57Bl/6 mice fed with a HFD to investigate the effects of granulocyte-colony stimulating factor (G-CSF), a cytokine known for its beneficial effects in the heart, on cardiac anatomical and functional abnormalities associated with obesity and type 2 diabetes. Groups of C57Bl/6 mice were fed with standard diet (n = 8) or HFD (n = 16). After 36 weeks, HFD animals were divided into a group treated with G-CSF + standard diet (n = 8) and a vehicle control group + standard diet (n = 8). Cardiac structure and function were assessed by electrocardiography, echocardiography and treadmill tests, in addition to the evaluation of body weight, fasting glicemia, insulin and glucose tolerance at different time points. Histological analyses were performed in the heart tissue. HFD consumption induced metabolic alterations characteristic of type 2 diabetes and obesity, as well as cardiac fibrosis and reduced exercise capacity. Upon returning to a standard diet, obese mice body weight returned to non-obese levels. G-CSF administration accelerated the reduction in of body weight in obese mice. Additionally, G-CSF treatment reduced insulin levels, diminished heart fibrosis, increased exercise capacity and reversed cardiac alterations, including bradycardia, elevated QRS amplitude, augmented P amplitude, increased septal wall thickness, left ventricular posterior thickening and cardiac output reduction. Our results indicate that G-CSF administration caused beneficial effects on obesity-associated cardiac impairment.

  7. The ECG Vertigo in Diabetes and Cardiac Autonomic Neuropathy

    OpenAIRE

    Voulgari, Christina; Tentolouris, Nicholas; Stefanadis, Christodoulos

    2011-01-01

    The importance of diabetes in the epidemiology of cardiovascular diseases cannot be overemphasized. About one third of acute myocardial infarction patients have diabetes, and its prevalence is steadily increasing. The decrease in cardiac mortality in people with diabetes is lagging behind that of the general population. Cardiovascular disease is a broad term which includes any condition causing pathological changes in blood vessels, cardiac muscle or valves, and cardiac rhythm. The ECG offers...

  8. [Assessment of professional practices in treating cardiac arrest].

    Science.gov (United States)

    Mazon, Clara; Kerrou, Yamina

    2017-12-01

    An assessment of professional practices was carried out in 2013-2014 with the aim of improving the treatment of cardiac arrest in hospitals. Two methods were used: an assessment by questionnaire to evaluate theoretical knowledge and a practical assessment of external cardiac massage. The results highlight the need for greater knowledge. The use of cardiac massage must be included in continuing professional development. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  9. NUTRITION SUPPORT COMPLICATIONS IN PATIENT WHO UNDERWENT CARDIAC SURGERY

    OpenAIRE

    Krdžalić, Alisa; Kovčić, Jasmina; Krdžalić, Goran; Jahić, Elmir

    2016-01-01

    Background: The nutrition support complications after cardiac surgery should be detected and treated on time. Aim: To show the incidence and type of nutritional support complication in patients after cardiac surgery. Methods: The prospective study included 415 patients who underwent cardiac surgery between 2010 and 2013 in Clinic for Cardiovascular Disease of University Clinical Center Tuzla. Complications of the delivery system for nutrition support (NS) and nutrition itself were analy...

  10. Biatrial Approach Provides Better Outcomes in the Surgical Treatment of Cardiac Myxomas

    Science.gov (United States)

    Yüksel, Ahmet; Saba, Davit; Velioğlu, Yusuf; Ener, Serdar; Özkan, Hayati

    2016-01-01

    Objective We aimed to present clinical features, surgical approaches, importance of surgical technique and long-term outcomes of our patients with cardiac myxoma who underwent surgery. Methods We retrospectively collected data of patients with cardiac myxoma who underwent surgical resection between February 1990 and November 2014. Biatrial approach is the preferred surgical method in a large proportion of patients that are operated due to left atrial myxoma because it provides wider exposure than the uniatrial approach. To prevent recurrence during surgical resection, a large excision is made so as to include at least 5 mm of normal area from clean tissue around the tumor. Moreover, special attention is paid to the excision that is made as a whole, without digesting the fragment of tumor with gentle dissections. Results Forty-three patients (20 males, mean age of 51.7±8.8 years) were included. Most common symptom was dyspnea (48.8%). Tumor was located in the left atrium in 37 (86%) patients. Resections were achieved via biatrial approach in 34 patients, uniatrial approach in 8 patients, and right atriotomy with right ventriculotomy in 1 patient. One patient died due to low cardiac output syndrome in the early postoperative period. Mean follow-up time was 102.3±66.5 months. Actuarial survival rates were 95%, 92% and 78% at five, 10 and 15 years, respectively. Recurrence was observed in none of the patients during follow-up. Conclusion Although myxomas are benign tumors, due to embolic complications and obstructive signs, they should be treated surgically as soon as possible after diagnosis. To prevent recurrence, especially in cardiac myxomas which are located in left atrium, preferred biatrial approach is suggested for wide resection of the tumor and to avoid residual tumor. PMID:27849304

  11. Biatrial Approach Provides Better Outcomes in the Surgical Treatment of Cardiac Myxomas

    Directory of Open Access Journals (Sweden)

    Ahmet Yüksel

    Full Text Available Abstract Objective: We aimed to present clinical features, surgical approaches, importance of surgical technique and long-term outcomes of our patients with cardiac myxoma who underwent surgery. Methods: We retrospectively collected data of patients with cardiac myxoma who underwent surgical resection between February 1990 and November 2014. Biatrial approach is the preferred surgical method in a large proportion of patients that are operated due to left atrial myxoma because it provides wider exposure than the uniatrial approach. To prevent recurrence during surgical resection, a large excision is made so as to include at least 5 mm of normal area from clean tissue around the tumor. Moreover, special attention is paid to the excision that is made as a whole, without digesting the fragment of tumor with gentle dissections. Results: Forty-three patients (20 males, mean age of 51.7±8.8 years were included. Most common symptom was dyspnea (48.8%. Tumor was located in the left atrium in 37 (86% patients. Resections were achieved via biatrial approach in 34 patients, uniatrial approach in 8 patients, and right atriotomy with right ventriculotomy in 1 patient. One patient died due to low cardiac output syndrome in the early postoperative period. Mean follow-up time was 102.3±66.5 months. Actuarial survival rates were 95%, 92% and 78% at five, 10 and 15 years, respectively. Recurrence was observed in none of the patients during follow-up. Conclusion: Although myxomas are benign tumors, due to embolic complications and obstructive signs, they should be treated surgically as soon as possible after diagnosis. To prevent recurrence, especially in cardiac myxomas which are located in left atrium, preferred biatrial approach is suggested for wide resection of the tumor and to avoid residual tumor.

  12. Passive output feedback and observer based autopilots: A comparative study

    Directory of Open Access Journals (Sweden)

    Marit Paulsen

    1996-04-01

    Full Text Available Two methods for course-keeping of a ship are studied where no measurements of the yaw rate are available. The two methods are a passive output feedback controller and a controller-observer structure. A comparison with special attention to stability and wave filtering properties, is provided. Finally, a case study of a ship autopilot is included.

  13. 36 CFR 1193.43 - Output, display, and control functions.

    Science.gov (United States)

    2010-07-01

    ... for the use of the product, through at least one mode in enhanced auditory fashion (i.e., increased... and use the product, including but not limited to, text, static or dynamic images, icons, labels... of audio cutoff. Where a product delivers audio output through an external speaker, provide an...

  14. Socially differentiated cardiac rehabilitation

    DEFF Research Database (Denmark)

    Meillier, Lucette Kirsten; Nielsen, Kirsten Melgaard; Larsen, Finn Breinholt

    2012-01-01

    cardiac rehabilitation programme. Methods: From 1 September 2002 to 31 December 2005, 388 first-incidence MI patients ≤75 years were hospitalised. Register check for newly hospitalised MI patients, screening interview, and systematic referral were conducted by a project nurse. Patients were referred...... to a standard rehabilitation programme (SRP). If patients were identified as socially vulnerable, they were offered an extended version of the rehabilitation programme (ERP). Excluded patients were offered home visits by a cardiac nurse. Concordance principles were used in the individualised programme elements......Aim: The comprehensive cardiac rehabilitation (CR) programme after myocardial infarction (MI) improves quality of life and results in reduced cardiac mortality and recurrence of MI. Hospitals worldwide face problems with low participation rates in rehabilitation programmes. Inequality...

  15. Cardiac Procedures and Surgeries

    Science.gov (United States)

    ... the Procedure Does A stent is a wire mesh tube used to prop open an artery during ... a Heart Attack • Heart Attack Tools & Resources • Support Network Heart Attack Tools & Resources My Cardiac Coach What ...

  16. Defining the Cardiac Fibroblast

    Science.gov (United States)

    Ivey, Malina J.; Tallquist, Michelle D.

    2017-01-01

    Cardiac fibrosis remains an important health concern, but the study of fibroblast biology has been hindered by a lack of effective means for identifying and tracking fibroblasts. Recent advances in fibroblast-specific lineage tags and reporters have permitted a better understanding of these cells. After injury multiple cell types have been implicated as the source for extracellular matrix producing cells, but emerging studies suggest that resident cardiac fibroblasts contribute substantially to the remodeling process. In this review, we discuss recent findings regarding cardiac fibroblast origin and identity. Our understanding of cardiac fibroblast biology and fibrosis is still developing and will expand profoundly in the next few years, with many of the recent findings regarding fibroblast gene expression and behavior laying down the groundwork for interpreting the purpose and utility of these cells before and after injury. PMID:27746422

  17. Cardiac Catheterization (For Parents)

    Science.gov (United States)

    ... cases, the doctor might call for a cardiac magnetic resonance imaging (MRI) scan or a CAT scan . ... first couple of days. This means no heavy lifting (more than 10 pounds) and no sports. After ...

  18. Cardiac Catheterization (For Teens)

    Science.gov (United States)

    ... doctor may also call for a cardiac MRI (magnetic resonance imaging) scan or a CT (computerized tomography) ... first couple of days. This means no heavy lifting (nothing over 10 pounds) and no sports. After ...

  19. Cardiac MRI and CT features of inheritable and congenital conditions associated with sudden cardiac death

    Energy Technology Data Exchange (ETDEWEB)

    Sparrow, Patrick; Merchant, Naeem; Provost, Yves; Doyle, Deirdre; Nguyen, Elsie; Paul, Narinder [University Health Network and Mount Sinai Hospital, Division of Cardiothoracic Imaging, Department of Medical Imaging, Toronto, Ontario (Canada)

    2009-02-15

    Cardiac MRI (CMR) and electrocardiogram (ECG)-gated multi-detector computed tomography (MDCT) are increasingly important tools in the identification and assessment of cardiac-related disease processes, including those associated with sudden cardiac death (SCD). While the commonest cause of SCD is coronary artery disease (CAD), in patients under 35 years inheritable cardiomyopathies such as hypertrophic cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy are important aetiologies. CMR in particular offers both accurate delineation of the morphological abnormalities associated with these and other conditions and the possibility for risk stratification for development of ventricular arrhythmias with demonstration of macroscopic scar by delayed enhancement imaging with intravenous gadolinium. (orig.)

  20. High Output Piezo/Triboelectric Hybrid Generator

    Science.gov (United States)

    Jung, Woo-Suk; Kang, Min-Gyu; Moon, Hi Gyu; Baek, Seung-Hyub; Yoon, Seok-Jin; Wang, Zhong-Lin; Kim, Sang-Woo; Kang, Chong-Yun

    2015-03-01

    Recently, piezoelectric and triboelectric energy harvesting devices have been developed to convert mechanical energy into electrical energy. Especially, it is well known that triboelectric nanogenerators have a simple structure and a high output voltage. However, whereas nanostructures improve the output of triboelectric generators, its fabrication process is still complicated and unfavorable in term of the large scale and long-time durability of the device. Here, we demonstrate a hybrid generator which does not use nanostructure but generates much higher output power by a small mechanical force and integrates piezoelectric generator into triboelectric generator, derived from the simultaneous use of piezoelectric and triboelectric mechanisms in one press-and-release cycle. This hybrid generator combines high piezoelectric output current and triboelectric output voltage, which produces peak output voltage of ~370 V, current density of ~12 μA.cm-2, and average power density of ~4.44 mW.cm-2. The output power successfully lit up 600 LED bulbs by the application of a 0.2 N mechanical force and it charged a 10 μF capacitor to 10 V in 25 s. Beyond energy harvesting, this work will provide new opportunities for developing a small, built-in power source in self-powered electronics such as mobile electronics.

  1. High Output Piezo/Triboelectric Hybrid Generator

    Science.gov (United States)

    Jung, Woo-Suk; Kang, Min-Gyu; Moon, Hi Gyu; Baek, Seung-Hyub; Yoon, Seok-Jin; Wang, Zhong-Lin; Kim, Sang-Woo; Kang, Chong-Yun

    2015-01-01

    Recently, piezoelectric and triboelectric energy harvesting devices have been developed to convert mechanical energy into electrical energy. Especially, it is well known that triboelectric nanogenerators have a simple structure and a high output voltage. However, whereas nanostructures improve the output of triboelectric generators, its fabrication process is still complicated and unfavorable in term of the large scale and long-time durability of the device. Here, we demonstrate a hybrid generator which does not use nanostructure but generates much higher output power by a small mechanical force and integrates piezoelectric generator into triboelectric generator, derived from the simultaneous use of piezoelectric and triboelectric mechanisms in one press-and-release cycle. This hybrid generator combines high piezoelectric output current and triboelectric output voltage, which produces peak output voltage of ~370 V, current density of ~12 μA·cm−2, and average power density of ~4.44 mW·cm−2. The output power successfully lit up 600 LED bulbs by the application of a 0.2 N mechanical force and it charged a 10 μF capacitor to 10 V in 25 s. Beyond energy harvesting, this work will provide new opportunities for developing a small, built-in power source in self-powered electronics such as mobile electronics. PMID:25791299

  2. Cardiac biomarkers in Neonatology

    OpenAIRE

    Vijlbrief, D.C.

    2015-01-01

    In this thesis, the role for cardiac biomarkers in neonatology was investigated. Several clinically relevant results were reported. In term and preterm infants, hypoxia and subsequent adaptation play an important role in cardiac biomarker elevation. The elevated natriuretic peptides are indicative of abnormal function; elevated troponins are suggestive for cardiomyocyte damage. This methodology makes these biomarkers of additional value in the treatment of newborn infants, separate or as a co...

  3. Awareness in cardiac anesthesia.

    LENUS (Irish Health Repository)

    Serfontein, Leon

    2010-02-01

    Cardiac surgery represents a sub-group of patients at significantly increased risk of intraoperative awareness. Relatively few recent publications have targeted the topic of awareness in this group. The aim of this review is to identify areas of awareness research that may equally be extrapolated to cardiac anesthesia in the attempt to increase understanding of the nature and significance of this scenario and how to reduce it.

  4. Role of pharmacotherapy in cardiac ion channelopathies.

    Science.gov (United States)

    El-Sherif, Nabil; Boutjdir, Mohamed

    2015-11-01

    In the last decade, there have been considerable advances in the understanding of the pathophysiology of malignant ventricular tachyarrhythmias (VT) and sudden cardiac death (SCD). Over 80% of SCD occurs in patients with organic heart disease. However, approximately 10%-15% of SCD occurs in the presence of structurally normal heart, and the majority of these patients are young. In this group of patients, changes in genes encoding cardiac ion channels produce modifications of the function of the channel resulting in an electrophysiological substrate of VT and SCD. Collectively, these disorders are referred to as cardiac ion channelopathies. The four major syndromes in this group are: the long QT syndrome (LQTS), the Brugada syndrome (BrS), the short QT syndrome (SQTS), and the catecholaminergic polymorphic ventricular tachycardia (CPVT). Each of these syndromes includes multiple subtypes with different and sometimes complex cardiac ion channel genetic abnormalities. Many are associated with other somatic and neurological abnormalities besides the risk of VT and SCD. The current management of cardiac ion channelopathies can be summarized as follows: (1) in symptomatic patients, the implantable cardioverter defibrillator (ICD) is the only viable option; (2) in asymptomatic patients, risk stratification is necessary, followed by either the ICD, pharmacotherapy, or a combination of both. A genotype-specific approach to pharmacotherapy requires a thorough understanding of the molecular-cellular basis of arrhythmogenesis in cardiac ion channelopathies as well as the specific drug profile. Copyright © 2015. Published by Elsevier Inc.

  5. Role of Circulating Fibrocytes in Cardiac Fibrosis.

    Science.gov (United States)

    Lin, Rong-Jie; Su, Zi-Zhuo; Liang, Shu-Min; Chen, Yu-Yang; Shu, Xiao-Rong; Nie, Ru-Qiong; Wang, Jing-Feng; Xie, Shuang-Lun

    2016-02-05

    It is revealed that circulating fibrocytes are elevated in patients/animals with cardiac fibrosis, and this review aims to provide an introduction to circulating fibrocytes and their role in cardiac fibrosis. This review is based on the data from 1994 to present obtained from PubMed. The search terms were "circulating fibrocytes " and "cardiac fibrosis ". Articles and critical reviews, which are related to circulating fibrocytes and cardiac fibrosis, were selected. Circulating fibrocytes, which are derived from hematopoietic stem cells, represent a subset of peripheral blood mononuclear cells exhibiting mixed morphological and molecular characteristics of hematopoietic and mesenchymal cells (CD34+/CD45+/collagen I+). They can produce extracellular matrix and many cytokines. It is shown that circulating fibrocytes participate in many fibrotic diseases, including cardiac fibrosis. Evidence accumulated in recent years shows that aging individuals and patients with hypertension, heart failure, coronary heart disease, and atrial fibrillation have more circulating fibrocytes in peripheral blood and/or heart tissue, and this elevation of circulating fibrocytes is correlated with the degree of fibrosis in the hearts. Circulating fibrocytes are effector cells in cardiac fibrosis.

  6. Impaired Cardiac Function and Cognitive Brain Aging.

    Science.gov (United States)

    van der Velpen, Isabelle F; Yancy, Clyde W; Sorond, Farzaneh A; Sabayan, Behnam

    2017-12-01

    It is well established that patients with heart failure are at a greater risk for dementia. Recent evidence suggests that the heart-brain link goes beyond advanced heart failure, and even suboptimal cardiac function is associated with brain structural and functional changes leading to cognitive impairment. In this review, we address several pathophysiological mechanisms underlying this association, including hemodynamic stress and cerebral hypoperfusion, neuroinflammation, cardiac arrhythmias, and hypercoagulation. The close link between cardiac function and brain health has numerous clinical and public health implications. Cardiac dysfunction and cognitive impairment are both common in older adults. However, in our current clinical practice, these medical conditions are generally evaluated and treated in isolation. Emerging evidence on the significance of the heart-brain link calls for comprehensive cardiovascular risk assessment in patients with cognitive impairment and a neurocognitive workup in patients with impaired cardiac function. A multidisciplinary approach by cardiologists, neurologists, and geriatricians would benefit the diagnostic process and disease management and ultimately improve the quality of life for patients with cardiac and cognitive dysfunction. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  7. Cardiac ankyrins in health and disease

    Science.gov (United States)

    Hashemi, Seyed M.; Hund, Thomas J.; Mohler, Peter J.

    2009-01-01

    Ankyrins are critical components of ion channel and transporter signaling complexes in the cardiovascular system. Over the past five years, ankyrin dysfunction has been linked with abnormal ion channel and transporter membrane organization and fatal human arrhythmias. Loss-of-function variants in the ankyrin-B gene (ANK2) cause “ankyrin-B syndrome” (previously called type 4 long QT syndrome), manifested by a complex cardiac phenotype including ventricular arrhythmias and sudden cardiac death. More recently, dysfunction in the ankyrin-B-based targeting pathway has been linked with a highly penetrant and severe form of human sinus node disease. Ankyrin-G (a second ankyrin gene product) is required for normal expression, membrane localization, and biophysical function of the primary cardiac voltage-gated sodium channel, Nav1.5. Loss of the ankyrin-G/Nav1.5 interaction is associated with human cardiac arrhythmia (Brugada syndrome). Finally, in the past year ankyrin dysfunction has been associated with more common arrhythmia and cardiovascular disease phenotypes. Specifically, large animal studies reveal striking remodeling of ankyrin-B and associated proteins following myocardial infarction. Additionally, the ANK2 locus has been linked with QTc interval variability in the general human population. Together, these findings identify a host of unanticipated and exciting roles for ankyrin polypeptides in cardiac function. More broadly, these findings illustrate the importance of local membrane organization for normal cardiac physiology. PMID:19394342

  8. Genetic variation for cardiac dysfunction in Drosophila.

    Directory of Open Access Journals (Sweden)

    Karen A Ocorr

    Full Text Available BACKGROUND: Common diseases may be attributed to combinations of variant alleles, but there are few model systems where the interactions among such variants can be studied in controlled genetic crosses. While association studies are designed to detect common polymorphisms of moderate effect, new approaches are required to characterize the impact on disease of interactions among rare alleles. METHODOLOGY/PRINCIPAL FINDINGS: We show that wild populations of Drosophila melanogaster harbor rare polymorphisms of major effect (RAME that predispose flies to a specific disease phenotype, age-dependent cardiac dysfunction. A screen of fifty inbred wild-type lines revealed a continuous spectrum of pacing-induced heart failure that generally increases in frequency with age. High-speed video analysis of the inbred lines with high rates of inducible heart failure indicates specific defects in cardiac function, including arrhythmias and contractile disorders ('cardiomyopathies'. A combination of bulked segregant analysis and single feature polymorphism (SFP detection localizes one of the cardiac susceptibility loci to the 97C interval on the fly genome. CONCLUSIONS/SIGNIFICANCE: Wild-type Drosophila, like humans, are predisposed to cardiac dysfunction. Identification of factors associated with these naturally occurring cardiac traits promises to provide important insights into the epidemiology of cardiac disease.

  9. Radiological characteristics of atrial myxoma in Cardiac Computed Tomography.

    Science.gov (United States)

    Haji, Kawa; Nasis, Arthur

    Although the primary role of Cardiac Computed Tomography (CCT) is assessment of the coronary arteries, the technique also allows detailed examination of cardiac structures and other cardiac pathologies including cardiac myxoma. However, limited data exists regarding the CCT characteristics of cardiac myxoma. To describe the radiological characteristics of a series of cardiac myxomas in CCT. We retrospectively identified all patients at our tertiary urban referral centre with cardiac myxoma on CCT over a seven-year period between July 2008 and July 2015. We describe the CCT characteristics of eight cases. Seven of them had histologically documented myxoma after surgical removal, while one patient had a lesion suggestive of myxoma on echocardiography and CCT. Eight patients were diagnosed with cardiac myxoma, comprising five females and three males. Seven of eight myxomas were located in the left atrium and one in the right atrium. Seven myxomas were polypoid in shape and one myxoma was villous. The average size was 22 × 26 mm. Calcification was present in half of the myxomas and average attenuation was 74 ± 46 Hounsfield Units. CCT has an important role in assessment of cardiac structures. This series highlights the radiological characteristics of cardiac myxoma. Copyright © 2017 Society of Cardiovascular Computed Tomography. All rights reserved.

  10. Neurological complications of cardiac surgery.

    Science.gov (United States)

    Gottesman, Rebecca F; McKhann, Guy M; Hogue, Charles W

    2008-11-01

    Neurological injury resulting from cardiac surgery has a range of manifestations from focal neurological deficit to encephalopathy or coma. As the safety of drug-eluting stents comes into question, more patients will likely undergo coronary artery bypass graft surgery. These projections, along with the growing proportions of elderly patients and those with comorbidities, portend the potential for rising rates of perioperative neurological complications. The risk for neurological injury may be determined by the type of procedure, by patient-specific characteristics, and by the extent of cerebral embolization and hypoperfusion during and after surgery. Changes in surgical techniques, including the use of off-pump surgery, have not decreased rates of brain injury from cardiac surgery. When appropriate, modern neuroimaging techniques should be used in postoperative patients to confirm diagnosis, to provide information on potential etiology, to direct appropriate therapy, and to help in prognostication. Management of postoperative medications and early use of rehabilitation services is a recommended strategy to optimize the recovery for individuals with neurological injury after cardiac surgery.

  11. Clinical application of cardiac SPECT

    International Nuclear Information System (INIS)

    Nishimura, Shigeyuki

    1999-01-01

    Single-photon emission computed tomography (SPECT) has replaced planar imaging techniques for myocardial scintigraphy. Thallium-201 was the dominant agent employed for myocardial perfusion imaging. Today new technetium-99m labelled radionuclides have been used as excellent alternatives to 201 Tl for detection of coronary artery disease, prognostification, and even assessment of myocardial viability. Pharmacologic stress imaging using either dipyridamole, adenosine or dobutamine is a substitute for exercise stress. Accurate determination of myocardial viability is vitally important for clinical decision making for patients with LV dysfunction who will most benefit from revascularization. Stunned and hibernated myocardium may result in profound regional LTV dysfunction in absence of necrosis. The various approach such as stress-redistribution-reinjection imaging, rest-redistribution imaging and stress-redistribution-24 hours delayed imaging has been utilized to assess myocardial viability with 201 Tl. Quantitative assessment of 99m Tc MIBI uptake reflect the degree of viability. 123 I-Metaiodobenzylguanidine (MIBG), an analog of norepinephrine, has been used for scintigraphic assessment of regional cardiac adrenergic innervation. Cardiac sympathetic denervation, assessed by 123 I-MIBG, due to ischemia in non-Q myocardial infarction and unstable angina has been shown. Quantitative cardiac MIBG scintigram was shown to have prognostic value in patients with severe congestive heart failure. 23 I-BMIPP (ρ-methyl-iodophenyl pentadecanoic acid) has been used to assess myocardial fatty acid utilization. BMIPP has the memory function of ischemia in unstable angina, since decreased BMIPP uptake persists several days after ischemic episode. Nuclear cardiology in Japan has experienced an expansion in the techniques including use of new radionuclides, 99m Tc perfusion agents, 123 I-MIBG and 23 I-BMIPP and in associated clinical application to the various cardiac diseases

  12. Clinical application of cardiac SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Shigeyuki [Yokohama Rosai Hospital (Japan)

    1999-07-01

    Single-photon emission computed tomography (SPECT) has replaced planar imaging techniques for myocardial scintigraphy. Thallium-201 was the dominant agent employed for myocardial perfusion imaging. Today new technetium-99m labelled radionuclides have been used as excellent alternatives to {sup 201}Tl for detection of coronary artery disease, prognostification, and even assessment of myocardial viability. Pharmacologic stress imaging using either dipyridamole, adenosine or dobutamine is a substitute for exercise stress. Accurate determination of myocardial viability is vitally important for clinical decision making for patients with LV dysfunction who will most benefit from revascularization. Stunned and hibernated myocardium may result in profound regional LTV dysfunction in absence of necrosis. The various approach such as stress-redistribution-reinjection imaging, rest-redistribution imaging and stress-redistribution-24 hours delayed imaging has been utilized to assess myocardial viability with {sup 201}Tl. Quantitative assessment of {sup 99m}Tc MIBI uptake reflect the degree of viability. {sup 123}I-Metaiodobenzylguanidine (MIBG), an analog of norepinephrine, has been used for scintigraphic assessment of regional cardiac adrenergic innervation. Cardiac sympathetic denervation, assessed by {sup 123}I-MIBG, due to ischemia in non-Q myocardial infarction and unstable angina has been shown. Quantitative cardiac MIBG scintigram was shown to have prognostic value in patients with severe congestive heart failure. {sup 23}I-BMIPP ({rho}-methyl-iodophenyl pentadecanoic acid) has been used to assess myocardial fatty acid utilization. BMIPP has the memory function of ischemia in unstable angina, since decreased BMIPP uptake persists several days after ischemic episode. Nuclear cardiology in Japan has experienced an expansion in the techniques including use of new radionuclides, {sup 99m}Tc perfusion agents, {sup 123}I-MIBG and {sup 23}I-BMIPP and in associated clinical

  13. Design of hydraulic output Stirling engine

    Science.gov (United States)

    Toscano, W. M.; Harvey, A. C.; Lee, K.

    1983-01-01

    A hydraulic output system for the RE-1000 free piston stirling engine (FPSE) was designed. The hydraulic output system can be readily integrated with the existing hot section of RE-1000 FPSE. The system has two simply supported diaphragms which separate the engine gas from the hydraulic fluid, a dynamic balance mechanism, and a novel, null center band hydraulic pump. The diaphragms are designed to endure more than 10 billion cycles, and to withstand the differential pressure load as high as 14 MPa. The projected thermodynamic performance of the hydraulic output version of RE-1000 FPSE is 1.87 kW at 29/7 percent brake efficiency.

  14. Primary Cardiac Lymphoma

    Directory of Open Access Journals (Sweden)

    Shu-Ching Hsueh

    2006-04-01

    Full Text Available Primary cardiac lymphoma (PCL has rarely been reported in Chinese populations. PCL mostly occurs in the right atrium. The clinical manifestations may be variable and are attributed to its location, the presence of congestive heart failure, pericardial effusion, arrhythmia, and cardiomegaly. The prognosis is usually poor because it is usually found too late and therefore, clinicians should be aware of PCL. Imaging examinations are the best methods for initial diagnosis and include echocardiography, computed tomography (CT scan, magnetic resonance imaging (MRI, and radioisotope scan. However, the final diagnosis is made by pathology, such as cytologic examination of the effusive fluid and tissue biopsy. Because the tumors are difficult to resect, the main treatment for the disease is chemotherapy, which can be successful. Here, we report a 58-year-old man who had a tumor measuring 8 × 5 cm in the right atrium. By clinical staging, including chest X-ray, echocardiography, CT scan of the abdomen, MRI of the heart, whole body tumor Gallium scan, and gastrointestinal series, no metastatic lesion or involvement was found in other parts of the body. Pathologic findings including cytology of pericardial effusion and heart tumor biopsy revealed the case as a diffuse large B-cell lymphoma. After chemotherapy with COP (cyclophosphamide + vincristine + prednisone and CHOPBE (COP + doxorubicin + bleomycin + etoposide regimens, the intracardiac tumor had disappeared, but the patient survived for 12 months in total, despite additional radiotherapy over the pericardial lesions. It was presumed that because the tumor was very large and involved all 3 layers of the heart, it did not respond as well to the therapy as expected.

  15. Improving health professionals' self-efficacy to support cardiac patients' emotional recovery: the 'Cardiac Blues Project'.

    Science.gov (United States)

    Murphy, Barbara M; Higgins, Rosemary O; Shand, Lyndel; Page, Karen; Holloway, Elizabeth; Le Grande, Michael R; Jackson, Alun C

    2017-02-01

    Many patients experience the 'cardiac blues' at the time of an acute cardiac event, and one in five go on to develop severe depression. These emotional responses often go undetected and unacknowledged. We initiated the 'Cardiac Blues Project' in order to help support patients' emotional recovery. As part of the project, we developed online training in order to support health professionals in the identification and management of the cardiac blues and depression. The aim of this study was to assess the acceptability of the training and its impacts on health professionals' self-efficacy. In July 2014, a 'cardiac blues' pack of patient resources, including access to health professional online training, was mailed to 606 centres across Australia. In the first 3 months after distribution, 140 health professionals registered to undertake the online training and participated in the present study. Participants provided information via a six-item pre- and post-training self-efficacy scale and on 10 post-training acceptability items. Health professionals' self-efficacy improved significantly after undertaking the online training across the six domains assessed and for the total score. Acceptability of the training was high across all 10 items assessed. Ratings of usefulness of the training in clinical practice were particularly favourable amongst those who worked directly with cardiac patients. The health professional training significantly improves health professionals' confidence in identifying and managing the 'cardiac blues' and depression. Monitoring of uptake is ongoing and future studies will investigate patient outcomes.

  16. Endogenous Money, Output and Prices in India

    OpenAIRE

    Das, Rituparna

    2009-01-01

    This paper proposes to quantify the macroeconometric relationships among the variables broad money, lending by banks, price, and output in India using simultaneous equations system keeping in view the issue of endogeneity.

  17. Multiple Input - Multiple Output (MIMO) SAR

    Data.gov (United States)

    National Aeronautics and Space Administration — This effort will research and implement advanced Multiple-Input Multiple-Output (MIMO) Synthetic Aperture Radar (SAR) techniques which have the potential to improve...

  18. The ECG vertigo in diabetes and cardiac autonomic neuropathy.

    Science.gov (United States)

    Voulgari, Christina; Tentolouris, Nicholas; Stefanadis, Christodoulos

    2011-01-01

    The importance of diabetes in the epidemiology of cardiovascular diseases cannot be overemphasized. About one third of acute myocardial infarction patients have diabetes, and its prevalence is steadily increasing. The decrease in cardiac mortality in people with diabetes is lagging behind that of the general population. Cardiovascular disease is a broad term which includes any condition causing pathological changes in blood vessels, cardiac muscle or valves, and cardiac rhythm. The ECG offers a quick, noninvasive clinical and research screen for the early detection of cardiovascular disease in diabetes. In this paper, the clinical and research value of the ECG is readdressed in diabetes and in the presence of cardiac autonomic neuropathy.

  19. Surgical Critical Care for the Trauma Patient with Cardiac Disease.

    Science.gov (United States)

    Woll, Michael M; Maerz, Linda L

    2016-12-01

    The elderly population is rapidly increasing in number. Therefore, geriatric trauma is becoming more prevalent. All practitioners caring for geriatric trauma patients should be familiar with the structural and functional changes naturally occurring in the aging heart, as well as common preexisting cardiac diseases in the geriatric population. Identification of the shock state related to cardiac dysfunction and targeted assessment of perfusion and resuscitation are important when managing elderly patients. Finally, management of cardiac dysfunction in the trauma patient includes an appreciation of the inherent effects of trauma on cardiac function. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Giant cardiac fibroma: an unusual cause of failure to thrive.

    Science.gov (United States)

    Navarini, Susanne; Latzin, Philipp; Kadner, Alexander; Carrel, Thierry; Hutter, Damian

    2013-06-01

    Cardiac fibromas are extremely rare in the general pediatric population and may present with a wide spectrum of clinical signs, including life-threatening arrhythmias and sudden death. We report a 14-month-old boy who presented with failure to thrive as the only symptom. Echocardiography showed a large cardiac fibroma in the right ventricle. Cardiac magnetic resonance imaging confirmed the diagnosis. After complete surgical tumor resection, the boy showed normal catch-up growth. This case underlines the diversity of clinical features of cardiac tumors, which implies that they should be considered early in the differential diagnosis of infants with failure to thrive.

  1. Developmental origin and lineage plasticity of endogenous cardiac stem cells

    Science.gov (United States)

    Santini, Maria Paola; Forte, Elvira; Harvey, Richard P.; Kovacic, Jason C.

    2016-01-01

    Over the past two decades, several populations of cardiac stem cells have been described in the adult mammalian heart. For the most part, however, their lineage origins and in vivo functions remain largely unexplored. This Review summarizes what is known about different populations of embryonic and adult cardiac stem cells, including KIT+, PDGFRα+, ISL1+ and SCA1+ cells, side population cells, cardiospheres and epicardial cells. We discuss their developmental origins and defining characteristics, and consider their possible contribution to heart organogenesis and regeneration. We also summarize the origin and plasticity of cardiac fibroblasts and circulating endothelial progenitor cells, and consider what role these cells have in contributing to cardiac repair. PMID:27095490

  2. Preoperative Feeding Neonates With Cardiac Disease.

    Science.gov (United States)

    Scahill, Carly J; Graham, Eric M; Atz, Andrew M; Bradley, Scott M; Kavarana, Minoo N; Zyblewski, Sinai C

    2017-01-01

    The potential for necrotizing enterocolitis (NEC) in neonates requiring cardiac surgery has contributed largely to wide feeding practice variations and a hesitation to initiate enteral feeding during the preoperative period, specifically those patients with hypoplastic left heart syndrome. A retrospective chart review of neonates undergoing cardiac surgery at a single institution between July 2011 and July 2013 was performed. The primary objective of this study was to determine if preoperative feeding was associated with NEC in neonates requiring cardiac surgery. Univariable and multivariable analyses were performed to evaluate the relationship between preoperative feeding and NEC. Secondary outcomes including growth failure, total ventilator days, total length of stay, and tube-assisted feeds at discharge were analyzed. One hundred thirty consecutive neonates who required cardiac surgery were included in the analysis. Preoperative feeding occurred in 61% (n = 79). The overall prevalence of NEC was 9% (12/130), including three neonates with surgical NEC. There was no difference in the prevalence of NEC between the preoperative feeding and nil per os (NPO) groups. Preoperative NPO status was associated with longer ventilator-dependent days ( P = .01) but was not associated with worsened growth failure, longer length of stay, or increased prevalence of tube-assisted feeds at discharge. In this study cohort, preoperative feeding was associated with a low prevalence of NEC. Larger prospective studies evaluating the safety and benefits of preoperative feeding in cardiac neonates are warranted.

  3. Cardiac sympathetic imaging with mIBG in cirrhosis and portal hypertension

    DEFF Research Database (Denmark)

    Møller, Søren; Mortensen, Christian; Bendtsen, Flemming

    2012-01-01

    Autonomic and cardiac dysfunction is frequent in cirrhosis and includes increased sympathetic nervous activity, impaired heart rate variability (HRV), and baroreflex sensitivity (BRS). Quantified (123)I-metaiodobenzylguanidine (mIBG) scintigraphy reflects cardiac noradrenaline uptake, and in pati......Autonomic and cardiac dysfunction is frequent in cirrhosis and includes increased sympathetic nervous activity, impaired heart rate variability (HRV), and baroreflex sensitivity (BRS). Quantified (123)I-metaiodobenzylguanidine (mIBG) scintigraphy reflects cardiac noradrenaline uptake...

  4. Assessment of cardiac function and circulatory status in critically ill patients

    Directory of Open Access Journals (Sweden)

    Gorazd Voga

    2007-12-01

    Full Text Available Background: Assessment of cardiac function and circulation is mandatory in almost all critically ill patients. In many patients morphological diagnosis of actual or pre-existing cardiac diseases and their functional consequences should be obtained.Methods: Cardiac function can be assessed by various non-invasive and invasive methods. The value of every method should be assessed according to its ability and reliability to assess preload, cardiac output and the adequacy of flow. In hemodinamically unstable patients frequent reassessment must be performed, because of rapid changes of patients’ conditions. Therefore, all methods for hemodynamic assessment in the ICU must be available on the 24 hours basis. Combined non-invasive and invasive approach to the assessment of cardiac function and circulation is preferred. After initial assessment of cardiac function according to clinical examination, electrocardiogram, chest X-ray and blood gas analysis, echocardiography is routinely used. When continuous monitoring of cardiac function is mandatory, complete invasive monitoring with pulmonary artery catheter and arterial line is employed. Monitoring of pulmonary pressures, continuous cardiac output, mixed venous blood oxygen saturation, and parameters of right ventricular function is the best choice to obtain complete information of hemodynamic situation. In patients with increased pulmonary vascular permeability the monitoring of cardiac output by pulse contour method together with measurement of intrathoracic blood volume and extravascular lung water could be even better choice.Conclusions: Assessment of cardiac function and circulatory status by rational use of various non-invasive and invasive methods is one of the essential components of critical care management.

  5. High-sensitive cardiac troponin T measurements in prediction of non-cardiac complications after major abdominal surgery.

    Science.gov (United States)

    Noordzij, P G; van Geffen, O; Dijkstra, I M; Boerma, D; Meinders, A J; Rettig, T C D; Eefting, F D; van Loon, D; van de Garde, E M W; van Dongen, E P A

    2015-06-01

    Postoperative non-cardiac complication rates are as high as 11-28% after high-risk abdominal procedures. Emerging evidence indicates that postoperative cardiac troponin T elevations are associated with adverse outcome in non-cardiac surgery. The aim of this study was to determine the relationship between postoperative high-sensitive cardiac troponin T elevations and non-cardiac complications in patients after major abdominal surgery. This prospective observational single-centre cohort study included patients at risk for coronary artery disease undergoing elective major abdominal surgery. Cardiac troponin was measured before surgery and at day 1, 3, and 7. Multivariable logistic regression analysis was performed to examine the adjusted association for different cut-off concentrations of postoperative myocardial injury and non-cardiac outcome. In 203 patients, 690 high-sensitive cardiac troponin T measurements were performed. Fifty-three patients (26%) had a non-cardiac complication within 30 days after surgery. Hospital mortality was 4% (8/203). An increase in cardiac troponin T concentration ≥100% compared with baseline was a superior independent predictor of non-cardiac postoperative clinical complications (adjusted odds ratio 4.3, 95% confidence interval 1.8-10.1, Phigh-sensitive cardiac troponin T increase ≥100% is a strong predictor of non-cardiac 30 day complications, increased hospital stay and hospital mortality in patients undergoing major abdominal surgery. NCT02150486. © The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Direct and simultaneous estimation of cardiac four chamber volumes by multioutput sparse regression.

    Science.gov (United States)

    Zhen, Xiantong; Zhang, Heye; Islam, Ali; Bhaduri, Mousumi; Chan, Ian; Li, Shuo

    2017-02-01

    Cardiac four-chamber volume estimation serves as a fundamental and crucial role in clinical quantitative analysis of whole heart functions. It is a challenging task due to the huge complexity of the four chambers including great appearance variations, huge shape deformation and interference between chambers. Direct estimation has recently emerged as an effective and convenient tool for cardiac ventricular volume estimation. However, existing direct estimation methods were specifically developed for one single ventricle, i.e., left ventricle (LV), or bi-ventricles; they can not be directly used for four chamber volume estimation due to the great combinatorial variability and highly complex anatomical interdependency of the four chambers. In this paper, we propose a new, general framework for direct and simultaneous four chamber volume estimation. We have addressed two key issues, i.e., cardiac image representation and simultaneous four chamber volume estimation, which enables accurate and efficient four-chamber volume estimation. We generate compact and discriminative image representations by supervised descriptor learning (SDL) which can remove irrelevant information and extract discriminative features. We propose direct and simultaneous four-chamber volume estimation by the multioutput sparse latent regression (MSLR), which enables jointly modeling nonlinear input-output relationships and capturing four-chamber interdependence. The proposed method is highly generalized, independent of imaging modalities, which provides a general regression framework that can be extensively used for clinical data prediction to achieve automated diagnosis. Experiments on both MR and CT images show that our method achieves high performance with a correlation coefficient of up to 0.921 with ground truth obtained manually by human experts, which is clinically significant and enables more accurate, convenient and comprehensive assessment of cardiac functions. Copyright © 2016 Elsevier

  7. Radiation Dose Estimation for Pediatric Patients Undergoing Cardiac Catheterization

    Science.gov (United States)

    Wang, Chu

    Patients undergoing cardiac catheterization are potentially at risk of radiation-induced health effects from the interventional fluoroscopic X-ray imaging used throughout the clinical procedure. The amount of radiation exposure is highly dependent on the complexity of the procedure and the level of optimization in imaging parameters applied by the clinician. For cardiac catheterization, patient radiation dosimetry, for key organs as well as whole-body effective, is challenging due to the lack of fixed imaging protocols, unlike other common X-ray based imaging modalities. Pediatric patients are at a greater risk compared to adults due to their greater cellular radio-sensitivities as well as longer remaining life-expectancy following the radiation exposure. In terms of radiation dosimetry, they are often more challenging due to greater variation in body size, which often triggers a wider range of imaging parameters in modern imaging systems with automatic dose rate modulation. The overall objective of this dissertation was to develop a comprehensive method of radiation dose estimation for pediatric patients undergoing cardiac catheterization. In this dissertation, the research is divided into two main parts: the Physics Component and the Clinical Component. A proof-of-principle study focused on two patient age groups (Newborn and Five-year-old), one popular biplane imaging system, and the clinical practice of two pediatric cardiologists at one large academic medical center. The Physics Component includes experiments relevant to the physical measurement of patient organ dose using high-sensitivity MOSFET dosimeters placed in anthropomorphic pediatric phantoms. First, the three-dimensional angular dependence of MOSFET detectors in scatter medium under fluoroscopic irradiation was characterized. A custom-made spherical scatter phantom was used to measure response variations in three-dimensional angular orientations. The results were to be used as angular dependence

  8. Dependency of blood pressure upon cardiac filling in patients with severe postural hypotension

    DEFF Research Database (Denmark)

    Mehlsen, J; Haedersdal, C; Stokholm, K H

    1994-01-01

    by vasoconstriction. The reduction in cardiac output resulted from reductions in left ventricular end-diastolic volumes with unchanged left ventricular ejection fractions and only moderate increments in heart rate. The study was demonstrated that blood pressure is strongly dependent upon cardiac filling in severe......Autonomic denervation of the vascular bed results theoretically in a stronger dependency of blood pressure upon intravascular volume, and the study described aimed at an investigation of the relation between cardiac filling and arterial blood pressure in patients with severe postural hypotension....... Seven patients were studied during head-up tilt at three different tilt angles using intra-arterial blood pressure recordings and estimates of left ventricular volumes by radioisotope ventriculography. Blood pressure fell dramatically during head-up tilt due to reductions in cardiac output unopposed...

  9. Power converter using near-load output capacitance, direct inductor contact, and/or remote current sense

    Energy Technology Data Exchange (ETDEWEB)

    Coteus, Paul W.; Ferencz, Andrew; Hall, Shawn A.; Takken, Todd E.; Tian, Shurong; Zhang, Xin

    2017-11-28

    An apparatus includes a first circuit board including first components including a load, and a second circuit board including second components including switching power devices and an output inductor. Ground and output voltage contacts between the circuit boards are made through soldered or connectorized interfaces. Certain components on the first circuit board and certain components, including the output inductor, on the second circuit board act as a DC-DC voltage converter for the load. An output capacitance for the conversion is on the first circuit board with no board-to-board interface between the output capacitance and the load. The inductance of the board-to-board interface functions as part of the output inductor's inductance and not as a parasitic inductance. Sense components for sensing current through the output inductor are located on the first circuit board. Parasitic inductance of the board-to-board interface has less effect on a sense signal provided to a controller.

  10. Power converter using near-load output capacitance, direct inductor contact, and/or remote current sense

    Science.gov (United States)

    Coteus, Paul W.; Ferencz, Andrew; Hall, Shawn A.; Takken, Todd E.; Tian, Shurong; Zhang, Xin

    2017-11-28

    An apparatus includes a first circuit board including first components including a load, and a second circuit board including second components including switching power devices and an output inductor. Ground and output voltage contacts between the circuit boards are made through soldered or connectorized interfaces. Certain components on the first circuit board and certain components, including the output inductor, on the second circuit board act as a DC-DC voltage converter for the load. An output capacitance for the conversion is on the first circuit board with no board-to-board interface between the output capacitance and the load. The inductance of the board-to-board interface functions as part of the output inductor's inductance and not as a parasitic inductance. Sense components for sensing current through the output inductor are located on the first circuit board. Parasitic inductance of the board-to-board interface has less effect on a sense signal provided to a controller.

  11. [Extracorporeal life support for treating cardiac arrest].

    Science.gov (United States)

    Lehot, Jean-Jacques; Long-Him-Nam, Nelly; Bastien, Olivier

    2011-12-01

    Percutaneous extracorporeal life support (ECLS) is now widespread for treating acute cardiac failure. ECLS has been used for treating in-hospital and out of hospital cardiac arrests. A systematic review of literature was performed in order to assess the results. Nine studies of in-hospital cardiac arrests were published between 2003 and January 31, 2011. They included 724 patients, 208 of which survived without significant neurological sequelae (28.7 %). In the other patients, the initial disease and the consequences of low flow brought multiorgan failure, or ECLS resulted in haemorrhage and ischaemia. Low flow lasted between 42 and 105 min (mean 54min). ECLS was used after out of hospital cardiac arrests in 3 studies published between 2008 and January 31, 2011. They included 110 patients of which only 6 survived (4.4 %) despite strict inclusion criteria. Low flow lasted between 60 and 120 min (mean 98 min.) According to these results the use of ECLS should be encouraged after in-hospital cardiac arrest and training in cardiorespiratory resuscitation should be improved in global population and health professionals.

  12. Cardiac contractility, central haemodynamics and blood pressure regulation during semistarvation

    DEFF Research Database (Denmark)

    Stokholm, K H; Breum, L; Astrup, A

    1991-01-01

    and equilibrium technique by [99Tcm]red blood cells). Cardiac output decreased concomitantly with the reduction in oxygen uptake as the calculated systemic arteriovenous difference of oxygen was unaltered. There were no significant decreases in left ventricular contractility indices, i.e. the ejection fraction......Eight obese patients were studied before and after 2 weeks of treatment by a very-low-calorie diet (VLCD). Cardiac output and central blood volume (pulmonary blood volume and left atrial volume) were determined by indicator dilution (125I-albumin) and radionuclide angiocardiography (first pass......, the peak ejection rate and changes in end-systolic volume. Also the diastolic function evaluated by the peak filling rate remained normal. Furthermore, no sign of backward failure could be demonstrated since the central blood volume was not significantly increased. Both systolic and diastolic blood...

  13. Cardiac safety in vascular access surgery and maintenance.

    Science.gov (United States)

    Malik, Jan; Kudlicka, Jaroslav; Tesar, Vladimir; Linhart, Ales

    2015-01-01

    More than 50% of all end-stage renal disease (ESRD) patients die from cardiovascular complications. Among them, heart failure and pulmonary hypertension play a major role, and published studies document significantly higher mortality rates in patients with these two states. Arteriovenous fistulas (AVF) and arteriovenous grafts (AVG) are the preferred types of vascular access (VA). However, both AVF and AVG increase cardiac output and in turn could contribute to (the decompensation of) heart failure or pulmonary hypertension. No really safe access flow volume exists, and the ESRD patients' reactions to it vary considerably. We review the mechanisms involved in the cardiovascular consequences of increased cardiac output and available literary data. The link between access flow volume and increased mortality due to pulmonary hypertension or heart failure probably exists, but still has not been directly evidenced. Regular echocardiography is advisable especially in patients with symptoms or with high VA flow (>1,500 ml/min). © 2015 S. Karger AG, Basel.

  14. Embryonic caffeine exposure acts via A1 adenosine receptors to alter adult cardiac function and DNA methylation in mice.

    Directory of Open Access Journals (Sweden)

    Daniela L Buscariollo

    Full Text Available Evidence indicates that disruption of normal prenatal development influences an individual's risk of developing obesity and cardiovascular disease as an adult. Thus, understanding how in utero exposure to chemical agents leads to increased susceptibility to adult diseases is a critical health related issue. Our aim was to determine whether adenosine A1 receptors (A1ARs mediate the long-term effects of in utero caffeine exposure on cardiac function and whether these long-term effects are the result of changes in DNA methylation patterns in adult hearts. Pregnant A1AR knockout mice were treated with caffeine (20 mg/kg or vehicle (0.09% NaCl i.p. at embryonic day 8.5. This caffeine treatment results in serum levels equivalent to the consumption of 2-4 cups of coffee in humans. After dams gave birth, offspring were examined at 8-10 weeks of age. A1AR+/+ offspring treated in utero with caffeine were 10% heavier than vehicle controls. Using echocardiography, we observed altered cardiac function and morphology in adult mice exposed to caffeine in utero. Caffeine treatment decreased cardiac output by 11% and increased left ventricular wall thickness by 29% during diastole. Using DNA methylation arrays, we identified altered DNA methylation patterns in A1AR+/+ caffeine treated hearts, including 7719 differentially methylated regions (DMRs within the genome and an overall decrease in DNA methylation of 26%. Analysis of genes associated with DMRs revealed that many are associated with cardiac hypertrophy. These data demonstrate that A1ARs mediate in utero caffeine effects on cardiac function and growth and that caffeine exposure leads to changes in DNA methylation.

  15. Embryonic Caffeine Exposure Acts via A1 Adenosine Receptors to Alter Adult Cardiac Function and DNA Methylation in Mice

    Science.gov (United States)

    Greenwood, Victoria; Xue, Huiling; Rivkees, Scott A.; Wendler, Christopher C.

    2014-01-01

    Evidence indicates that disruption of normal prenatal development influences an individual's risk of developing obesity and cardiovascular disease as an adult. Thus, understanding how in utero exposure to chemical agents leads to increased susceptibility to adult diseases is a critical health related issue. Our aim was to determine whether adenosine A1 receptors (A1ARs) mediate the long-term effects of in utero caffeine exposure on cardiac function and whether these long-term effects are the result of changes in DNA methylation patterns in adult hearts. Pregnant A1AR knockout mice were treated with caffeine (20 mg/kg) or vehicle (0.09% NaCl) i.p. at embryonic day 8.5. This caffeine treatment results in serum levels equivalent to the consumption of 2–4 cups of coffee in humans. After dams gave birth, offspring were examined at 8–10 weeks of age. A1AR+/+ offspring treated in utero with caffeine were 10% heavier than vehicle controls. Using echocardiography, we observed altered cardiac function and morphology in adult mice exposed to caffeine in utero. Caffeine treatment decreased cardiac output by 11% and increased left ventricular wall thickness by 29% during diastole. Using DNA methylation arrays, we identified altered DNA methylation patterns in A1AR+/+ caffeine treated hearts, including 7719 differentially methylated regions (DMRs) within the genome and an overall decrease in DNA methylation of 26%. Analysis of genes associated with DMRs revealed that many are associated with cardiac hypertrophy. These data demonstrate that A1ARs mediate in utero caffeine effects on cardiac function and growth and that caffeine exposure leads to changes in DNA methylation. PMID:24475304

  16. Comprehensive cardiac rehabilitation

    DEFF Research Database (Denmark)

    Kruse, Marie; Hochstrasser, Stefan; Zwisler, Ann-Dorthe O

    2006-01-01

    OBJECTIVES: The costs of comprehensive cardiac rehabilitation are established and compared to the corresponding costs of usual care. The effect on health-related quality of life is analyzed. METHODS: An unprecedented and very detailed cost assessment was carried out, as no guidelines existed...... for the situation at hand. Due to challenging circumstances, the cost assessment turned out to be ex-post and top-down. RESULTS: Cost per treatment sequence is estimated to be approximately euro 976, whereas the incremental cost (compared with usual care) is approximately euro 682. The cost estimate is uncertain...... and may be as high as euro 1.877. CONCLUSIONS: Comprehensive cardiac rehabilitation is more costly than usual care, and the higher costs are not outweighed by a quality of life gain. Comprehensive cardiac rehabilitation is, therefore, not cost-effective....

  17. Biomimetic material strategies for cardiac tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Prabhakaran, Molamma P., E-mail: nnimpp@nus.edu.sg [Health Care and Energy Materials Laboratory, Nanoscience and Nanotechnology Initiative, Faculty of Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576 (Singapore); Venugopal, J. [Health Care and Energy Materials Laboratory, Nanoscience and Nanotechnology Initiative, Faculty of Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576 (Singapore); Kai, Dan [NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore (Singapore); Ramakrishna, Seeram [Health Care and Energy Materials Laboratory, Nanoscience and Nanotechnology Initiative, Faculty of Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576 (Singapore)

    2011-04-08

    Cardiovascular disease precedes many serious complications including myocardial infarction (MI) and it remains a major problem for the global community. Adult mammalian heart has limited ability to regenerate and compensate for the loss of cardiomyocytes. Restoration of cardiac function by replacement of diseased myocardium with functional cardiomyocytes is an intriguing strategy because it offers a potential cure for MI. Biomaterials are fabricated in nanometer scale dimensions by combining the chemical, biological, mechanical and electrical aspects of material for potential tissue engineering (TE) applications. Synthetic polymers offer advantageous in their ability to tailor the mechanical properties, and natural polymers offer cell recognition sites necessary for cell, adhesion and proliferation. Cardiac tissue engineering (TE) aim for the development of a bioengineered construct that can provide physical support to the damaged cardiac tissue by replacing certain functions of the damaged extracellular matrix and prevent adverse cardiac remodeling and dysfunction after MI. Electrospun nanofibers are applied as heart muscle patches, while hydrogels serve as a platform for controlled delivery of growth factors, prevent mechanical complications and assist in cell recruitment. This article reviews the applications of different natural and synthetic polymeric materials utilized as cardiac patches, injectables or 3D constructs for cardiac TE. Smart organization of nanoscale assemblies with synergistic approaches of utilizing nanofibers and hydrogels could further advance the field of cardiac tissue engineering. Rapid innovations in biomedical engineering and cell biology will bring about new insights in the development of optimal scaffolds and methods to create tissue constructs with relevant contractile properties and electrical integration to replace or substitute the diseased myocardium.

  18. Cardiac optogenetics : using light to monitor cardiac physiology

    NARCIS (Netherlands)

    Koopman, Charlotte D.|info:eu-repo/dai/nl/41375491X; Zimmermann, Wolfram-Hubertus; Knöpfel, Thomas; de Boer, Teun P.|info:eu-repo/dai/nl/30481878X

    2017-01-01

    Our current understanding of cardiac excitation and its coupling to contraction is largely based on ex vivo studies utilising fluorescent organic dyes to assess cardiac action potentials and signal transduction. Recent advances in optogenetic sensors open exciting new possibilities for cardiac

  19. A Hierarchical Multi-Output Nearest Neighbor Model for Multi-Output Dependence Learning

    OpenAIRE

    Morris, Richard G.; Martinez, Tony; Smith, Michael R.

    2014-01-01

    Multi-Output Dependence (MOD) learning is a generalization of standard classification problems that allows for multiple outputs that are dependent on each other. A primary issue that arises in the context of MOD learning is that for any given input pattern there can be multiple correct output patterns. This changes the learning task from function approximation to relation approximation. Previous algorithms do not consider this problem, and thus cannot be readily applied to MOD problems. To pe...

  20. Quantitative cardiac computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Thelen, M.; Dueber, C.; Wolff, P.; Erbel, R.; Hoffmann, T.

    1985-06-01

    The scope and limitations of quantitative cardiac CT have been evaluated in a series of experimental and clinical studies. The left ventricular muscle mass was estimated by computed tomography in 19 dogs (using volumetric methods, measurements in two axes and planes and reference volume). There was good correlation with anatomical findings. The enddiastolic volume of the left ventricle was estimated in 22 patients with cardiomyopathies; using angiography as a reference, CT led to systematic under-estimation. It is also shown that ECG-triggered magnetic resonance tomography results in improved visualisation and may be expected to improve measurements of cardiac morphology.

  1. Assessment of paediatric hydronephrosis using output efficiency

    International Nuclear Information System (INIS)

    Saundres, C.A.B.; Choong, K.K.L.; Gruenewald, S.M.

    1998-01-01

    Full text: Diuretic renography is an important tool in the evaluation of paediatric hydronephrosis. Recently a newly developed parameter, output efficiency (OE) has allowed normalisation of washout according to renal function. We retrospectively reviewed the diagnostic accuracy of OE in 56 children (70 hydronephrotic kidneys). There were 16 females and 41 males (mean age 1.4 years, range 3 weeks-12 years). Diuretic renography ( 99m Tc-MAG3) was performed using i.v. volume expansion (15 mL/kg), frusemide diuresis (1mg/kg) and urethral catheterisation if VUR was present. Final diagnosis was made using surgery (n = 15) or clinical outcome (n = 42). Clinical follow up exceeded one year and included repeat MAG3 scan (n = 20), resolving hydronephrosis on ultrasound (n = 15) or percutaneous antegrade pyelogram (n = 1). Initial scans were classified as obstructed (n 13), indeterminate (n = 13) or non obstructed (n = 30) based on standard qualitative and quantitative criteria. Using a normal range of >84%, OE correctly predicted 12/13 (92%) obstructed kidneys and 44/44 non-obstructed kidneys (100%). In the indeterminate group, three kidneys developed obstruction at follow -up and 10 became non obstructed. Initial OE predicted outcome in two and four kidneys respectively. Overall, OE sensitivity and specificity were 88% and 89%. In the subgroup of patients (n = 19) with reduced differential function (<40%) the sensitivity of OE was 100% and specificity was 75%. This compares to 83% and 66% for Tl/2 in this subgroup. Therefore OE is a useful marker of renal outflow tract obstruction and maybe superior to other parameters such as Tl/2 particularly when renal function is reduced

  2. Impact of extracorporeal blood flow rate on blood pressure, pulse rate and cardiac output during haemodialysis

    DEFF Research Database (Denmark)

    Schytz, Philip Andreas; Mace, Maria Lerche; Soja, Anne Merete Boas

    2015-01-01

    BACKGROUND: If blood pressure (BP) falls during haemodialysis (HD) [intradialytic hypotension (IDH)] a common clinical practice is to reduce the extracorporeal blood flow rate (EBFR). Consequently the efficacy of the HD (Kt/V) is reduced. However, only very limited knowledge on the effect......, respectively. RESULTS: Mean (SD) age was 71 (11) years. Systolic BP was significantly higher at an EBFR of 200 mL/min as compared with 300 mL/min [133 (23) versus 128 (24) mmHg; P ...L/min diastolic BP, mean arterial pressure, PR and CO remained unchanged. CONCLUSION: Our study does not show any consistent trend in BP changes by a reduction in EBFR. Reduction in EBFR if BP falls during IDH is thus not supported. However, none of the patients experienced IDH. Further studies are required...

  3. Comparison of an Endotracheal Cardiac Output Monitor to a Pulmonary Artery Catheter

    Science.gov (United States)

    2017-12-04

    ile methods of fluid resuscitation remain controversial , maintenance of a patent airway and hemodynamic stabi lity as indicated by invasive...Edwards LifeSciences, Irvine, CA) pulmonary artery catheter (PAC) under hypothermic and hemorrhagic conditions. Methods Power analysis (G*Power...3.1) suggested 8 an imals would be sufficient for comparisons. After induction of anesthesia, instrumentation , and stabilization in experiment 1

  4. Mechanisms of increase in cardiac output during acute weightlessness in humans

    DEFF Research Database (Denmark)

    Petersen, Lonnie G; Damgaard, Morten; Petersen, Johan Casper Grove

    2011-01-01

    by parabolic flight increased CO by 1.7 ± 0.4 l/min (P ... in CO during acute 0 G in seated humans. A Bainbridge-like reflex could be the mechanism for the HR-induced increase in CO during 0 G in particular in supine subjects....

  5. Monitoring cardiac output during hyperbaric oxygen treatment of haemodynamically unstable patients

    DEFF Research Database (Denmark)

    Hansen, Marco Bo; Treschow, Frederik; Skielboe, Martin

    2013-01-01

    Patients suffering from necrotizing fasciitis (NF) are often haemodynamically unstable and require extended monitoring of cardiovascular parameters; yet this is limited during hyperbaric oxygen treatment (HBOT). We aimed to evaluate the use and safety of transoesophageal Doppler (TED) monitoring...

  6. Evaluation of cerebral electrical activity and cardiac output after patent ductus arteriosus ligation in preterm infants.

    LENUS (Irish Health Repository)

    Leslie, A T F S

    2013-11-01

    To characterize and investigate the relationship between systemic blood flow and pre- and postoperative cerebral electrical activity in preterm neonates undergoing patent ductus arteriosus (PDA) ligation.

  7. Assessment of cardiac output with transpulmonary thermodilution during exercise in humans

    DEFF Research Database (Denmark)

    Calbet, José A L; Boushel, Robert

    2015-01-01

    and intrathoracic blood volume, as well as extravascular lung water (EVLW) in resting humans. It remains unknown if this technique is also accurate and reproducible during exercise. Sixteen healthy men underwent catheterization of the right femoral vein (for iced saline injection), an antecubital vein (ICG...

  8. Problems in Modelling Charge Output Accelerometers

    Directory of Open Access Journals (Sweden)

    Tomczyk Krzysztof

    2016-12-01

    Full Text Available The paper presents major issues associated with the problem of modelling change output accelerometers. The presented solutions are based on the weighted least squares (WLS method using transformation of the complex frequency response of the sensors. The main assumptions of the WLS method and a mathematical model of charge output accelerometers are presented in first two sections of this paper. In the next sections applying the WLS method to estimation of the accelerometer model parameters is discussed and the associated uncertainties are determined. Finally, the results of modelling a PCB357B73 charge output accelerometer are analysed in the last section of this paper. All calculations were executed using the MathCad software program. The main stages of these calculations are presented in Appendices A−E.

  9. Bringing home the bacon? The next step in cardiac sodium channelopathies

    NARCIS (Netherlands)

    Wilde, Arthur A. M.; Postema, Pieter G.

    2015-01-01

    Mutations in SCN5A, which encodes the α subunit of the major cardiac sodium channel Na(V)1.5, are associated with multiple cardiac arrhythmias, including Brugada syndrome. It is not clear why mutations in SCN5A result in such a variety of cardiac phenotypes, and introduction of analogous Scn5a

  10. Evidence for increased cardiac compliance during exposure to simulated microgravity.

    Science.gov (United States)

    Koenig, S C; Convertino, V A; Fanton, J W; Reister, C A; Gaffney, F A; Ludwig, D A; Krotov, V P; Trambovetsky, E V; Latham, R D

    1998-10-01

    We measured hemodynamic responses during 4 days of head-down tilt (HDT) and during graded lower body negative pressure (LBNP) in invasively instrumented rhesus monkeys to test the hypotheses that exposure to simulated microgravity increases cardiac compliance and that decreased stroke volume, cardiac output, and orthostatic tolerance are associated with reduced left ventricular peak dP/dt. Six monkeys underwent two 4-day (96 h) experimental conditions separated by 9 days of ambulatory activities in a crossover counterbalance design: 1) continuous exposure to 10 degrees HDT and 2) approximately 12-14 h per day of 80 degrees head-up tilt and 10-12 h supine (control condition). Each animal underwent measurements of central venous pressure (CVP), left ventricular and aortic pressures, stroke volume, esophageal pressure (EsP), plasma volume, alpha1- and beta1-adrenergic responsiveness, and tolerance to LBNP. HDT induced a hypovolemic and hypoadrenergic state with reduced LBNP tolerance compared with the control condition. Decreased LBNP tolerance with HDT was associated with reduced stroke volume, cardiac output, and peak dP/dt. Compared with the control condition, a 34% reduction in CVP (P = 0.010) and no change in left ventricular end-diastolic area during HDT was associated with increased ventricular compliance (P = 0.0053). Increased cardiac compliance could not be explained by reduced intrathoracic pressure since EsP was unaltered by HDT. Our data provide the first direct evidence that increased cardiac compliance was associated with headward fluid shifts similar to those induced by exposure to spaceflight and that reduced orthostatic tolerance was associated with lower cardiac contractility.

  11. Cardiac CT angiography in children with congenital heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Siripornpitak, Suvipaporn, E-mail: ssiripornpitak@yahoo.com [Division of Diagnostic Radiology, Department of Diagnostic and Therapeutic Radiology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok (Thailand); Pornkul, Ratanaporn [Division of Diagnostic Radiology, Department of Diagnostic and Therapeutic Radiology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok (Thailand); Khowsathit, Pongsak [Pediatric Cardiac Unit, Department of Pediatrics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok (Thailand); Layangool, Thanarat; Promphan, Worakan [Pediatric Cardiology Unit, Queen Sirikit National Institute of Child Health, Bangkok (Thailand); Pongpanich, Boonchob [Pediatric Cardiac Unit, Department of Pediatrics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok (Thailand)

    2013-07-15

    Cardiac imaging plays an important role in both congenital and acquired heart diseases. Cardiac computed tomography (angiography) cCT(A) is a non-invasive, increasingly popular, complementary modality to echocardiography in evaluation of congenital heart diseases (CHD) in children. Despite radiation exposure, cCT(A) is now commonly used for evaluation of the complex CHD, giving information of both intra-cardiac and extra-cardiac anatomy, coronary arteries, and vascular structures. This review article will focus on the fundamentals and essentials for performing cCT(A) in children, including radiation dose awareness, basic techniques, and strengths and weaknesses of cCT(A) compared with cardiac magnetic resonance imaging (cMRI), and applications. The limitations of this modality will also be discussed, including the CHD for which cMRI may be substituted.

  12. The light output of BGO crystals

    International Nuclear Information System (INIS)

    Gong Zhufang; Ma Wengan; Lin Zhirong; Wang Zhaomin; Xu Zhizong; Fan Yangmei

    1987-01-01

    The dependence of light output on the surface treatment of BGO crystals has been tested. The results of experiments and Monte Carlo calculation indicate that for a tapered BGO crystal the best way to improve the uniformity and the energy resolution and to obtain higher light output is roughing the surface coupled to photomultiplier tube. The authors also observed that different wrapping method can effect its uniformity and resolutoin. Monte Carlo calculation indicates that the higher one of the 'double peaks' is the photoelectron peak of γ rays

  13. What shapes output of policy reform?

    DEFF Research Database (Denmark)

    Carlsen, Kirsten

    and personal benefits. Rather, the thesis shows how state actors decisions are shaped by a complex inter-relation of circumstances, interests and resources at play during the level of policy implementation. Thesis findings are based on collection and analysis of qualitative data collected from actors within...... and with a particular focus on the factors influencing reform output. The main message is that state actor decisions are central determinants for the ways in which reform output is shaped. It contests political economy theory by showing that these decisions are not only determined by state actors sole pursuit of power...

  14. Practical textbook of cardiac CT and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Tae-Hwan (ed.) [ASAN Medical Center, Seoul (Korea, Republic of). Dept. of Radiology

    2015-04-01

    Guide to the interpretation of cardiac CT and MRI for the purposes of diagnosis, treatment planning, and follow-up. Emphasis on applications in a wide range of real clinical situations. Numerous informative illustrations. Summarizing sections permitting rapid retrieval of information. QR codes allowing access to references, additional figures, and motion pictures from the internet. This up-to-date textbook comprehensively reviews all aspects of cardiac CT and MRI and demonstrates the value of these techniques in clinical practice. A wide range of applications are considered, including imaging of atherosclerotic and non-atherosclerotic coronary artery disease, coronary revascularization, ischemic heart disease, non-ischemic cardiomyopathy, valvular heart disease, cardiac tumors, and pericardial disease. The numerous high-quality images illustrate how to interpret cardiac CT and MRI correctly for the purposes of diagnosis, treatment planning, and follow-up. Helpful summarizing sections in every chapter will facilitate rapid retrieval of information. This book will be of great value to radiologists and cardiologists seeking a reliable guide to the optimal use of cardiac CT and MRI in real clinical situations.

  15. Practical textbook of cardiac CT and MRI

    International Nuclear Information System (INIS)

    Lim, Tae-Hwan

    2015-01-01

    Guide to the interpretation of cardiac CT and MRI for the purposes of diagnosis, treatment planning, and follow-up. Emphasis on applications in a wide range of real clinical situations. Numerous informative illustrations. Summarizing sections permitting rapid retrieval of information. QR codes allowing access to references, additional figures, and motion pictures from the internet. This up-to-date textbook comprehensively reviews all aspects of cardiac CT and MRI and demonstrates the value of these techniques in clinical practice. A wide range of applications are considered, including imaging of atherosclerotic and non-atherosclerotic coronary artery disease, coronary revascularization, ischemic heart disease, non-ischemic cardiomyopathy, valvular heart disease, cardiac tumors, and pericardial disease. The numerous high-quality images illustrate how to interpret cardiac CT and MRI correctly for the purposes of diagnosis, treatment planning, and follow-up. Helpful summarizing sections in every chapter will facilitate rapid retrieval of information. This book will be of great value to radiologists and cardiologists seeking a reliable guide to the optimal use of cardiac CT and MRI in real clinical situations.

  16. An Advanced simulation Code for Modeling Inductive Output Tubes

    Energy Technology Data Exchange (ETDEWEB)

    Thuc Bui; R. Lawrence Ives

    2012-04-27

    During the Phase I program, CCR completed several major building blocks for a 3D large signal, inductive output tube (IOT) code using modern computer language and programming techniques. These included a 3D, Helmholtz, time-harmonic, field solver with a fully functional graphical user interface (GUI), automeshing and adaptivity. Other building blocks included the improved electrostatic Poisson solver with temporal boundary conditions to provide temporal fields for the time-stepping particle pusher as well as the self electric field caused by time-varying space charge. The magnetostatic field solver was also updated to solve for the self magnetic field caused by time changing current density in the output cavity gap. The goal function to optimize an IOT cavity was also formulated, and the optimization methodologies were investigated.

  17. SCALPLO, Plotting of Flux Output from SCALE Program

    International Nuclear Information System (INIS)

    Hersman, A.; De Leege, P.F.A.; Hoogenboom, J.E.

    1993-01-01

    1 - Description of program or function: SCALPLO is a plot program, designed to plot flux, power and spectrum information. Data exchange between SCALE modules and SCALPLO is via CCCC-interface files. As not all modules can produce these files, there are special routines supplied with SCALPLO that can produce CCCC-like files. These routines can be included in the code and for XSDRPM, CITATION, ANISN and DOT, the place to include these routines is supplied. 2 - Method of solution: SCALPLO consists of two sections. Firstly the pre-processor, which selects and reads the required data. Secondly the plot section which produces the plot on the selected output device. 3 - Restrictions on the complexity of the problem: SCALPLO requires DISSPLA version 11.0 or higher. The choice of output device depends on the devices installed

  18. Spectrum of cardiac involvement in neonatal lupus.

    Science.gov (United States)

    Hornberger, L K; Al Rajaa, N

    2010-09-01

    'Neonatal' lupus erythematosus (NLE) describes a clinical spectrum of cardiac and non-cardiac abnormalities observed in neonates and foetuses whose mothers have the auto-antibodies anti-SSA/Ro (anti-Ro) and anti-SSB/La (anti-La). Of the cardiac abnormalities, congenital AVB is the most common cardiovascular abnormality found in affected foetuses and infants. Many other cardiovascular manifestations of NLE have been more recently recognized including atrial and ventricular arrhythmias and other conduction abnormalities, myocarditis, cardiomyopathy often with endocardiofibroelastosis and structural heart disease, particularly valvar lesions. In this report, the spectrum of cardiovascular manifestations observed in foetuses and infants with NLE are reviewed and the pathogenesis, diagnosis and clinical outcomes are briefly discussed.

  19. Neonatal cardiac emergencies

    African Journals Online (AJOL)

    Neonatal cardiac emergencies. The neonatal period is one that fills many generalists with fear – this article will help to dispel these concerns. George A Comitis, MB ChB, DCH (SA), DA (SA), FCPaed (SA), Cert Cardiology (SA) Paed. Consultant, Paediatric Cardiology Service of the Western Cape, Red Cross War Memorial ...

  20. Nonexercise cardiac stress testing

    International Nuclear Information System (INIS)

    Vacek, J.L.; Baldwin, T.

    1989-01-01

    Many patients who require evaluation for coronary artery disease are unable to undergo exercise stress testing because of physiologic or psychological limitations. Drs Vacek and Baldwin describe three alternative methods for assessment of cardiac function in these patients, all of which have high levels of diagnostic sensitivity and specificity. 23 references

  1. Cardiac magnetic resonance imaging

    African Journals Online (AJOL)

    2011-03-06

    Mar 6, 2011 ... Bruce Spottiswoode has a BSc in Electrical Engineering from the University of the Witwatersrand and a PhD in Biomedical Engineering on cardiac MRI from the. University of Cape Town. He has worked on developing electronics for the CSIR, on MRI image reconstruction for Siemens, and on X-ray imaging ...

  2. Cardiac magnetic resonance imaging

    African Journals Online (AJOL)

    2011-03-06

    Mar 6, 2011 ... Cardiac magnetic resonance imaging. Cardiovascular magnetic resonance imaging is becoming a routine diagnostic technique. BRUCE s sPOTTiswOOdE, PhD. MRC/UCT Medical Imaging Research Unit, University of Cape Town, and Division of Radiology, Stellenbosch University. Bruce Spottiswoode ...

  3. Post cardiac injury syndrome

    DEFF Research Database (Denmark)

    Nielsen, S L; Nielsen, F E

    1991-01-01

    The post-pericardiotomy syndrome is a symptom complex which is similar in many respects to the post-myocardial infarction syndrome and these are summarized under the diagnosis of the Post Cardiac Injury Syndrome (PCIS). This condition, which is observed most frequently after open heart surgery...

  4. Early goal-directed therapy in moderate to high-risk cardiac surgery patients

    Directory of Open Access Journals (Sweden)

    Kapoor Poonam

    2008-01-01

    Full Text Available Early goal-directed therapy is a term used to describe the guidance of intravenous fluid and vasopressor/inotropic therapy by using cardiac output or similar parameters in the immediate post-cardiopulmonary bypass in cardiac surgery patients. Early recognition and therapy during this period may result in better outcome. In keeping with this aim in the cardiac surgery patients, we conducted the present study. The study included 30 patients of both sexes, with EuroSCORE ≥3 undergoing coronary artery bypass surgery under cardiopulmonary bypass. The patients were randomly divided into two groups, namely, control and early goal-directed therapy (EGDT groups. All the subjects received standardized care; arterial pressure was monitored through radial artery, central venous pressure through a triple lumen in the right internal jugular vein, electrocardiogram, oxygen saturation, temperature, urine output per hour and frequent arterial blood gas analysis. In addition, cardiac index monitoring using FloTrac™ and continuous central venous oxygen saturation using PreSep™ was used in patients in the EGTD group. Our aim was to maintain the cardiac index at 2.5-4.2 l/min/m 2 , stroke volume index 30-65 ml/beat/m 2 , systemic vascular resistance index 1500-2500 dynes/s/cm 5 /m 2 , oxygen delivery index 450-600 ml/min/m 2 , continuous central venous oximetry more than 70%, stroke volume variation less than 10%; in addition to the control group parameters such as central venous pressure 6-8 mmHg, mean arterial pressure 90-105 mmHg, normal arterial blood gas analysis values, pulse oximetry, hematocrit value above 30% and urine output more than 1 ml/kg/h. The aims were achieved by altering the administration of intravenous fluids and doses of inotropic or vasodilator agents. Three patients were excluded from the study and the data of 27 patients analyzed. The extra volume used (330 ± 160 v/s 80 ± 80 ml, P = 0.043 number of adjustments of inotropic agents (3

  5. Reduced Right Ventricular Function Predicts Long-Term Cardiac Re-Hospitalization after Cardiac Surgery.

    Directory of Open Access Journals (Sweden)

    Leela K Lella

    Full Text Available The significance of right ventricular ejection fraction (RVEF, independent of left ventricular ejection fraction (LVEF, following isolated coronary artery bypass grafting (CABG and valve procedures remains unknown. The aim of this study is to examine the significance of abnormal RVEF by cardiac magnetic resonance (CMR, independent of LVEF in predicting outcomes of patients undergoing isolated CABG and valve surgery.From 2007 to 2009, 109 consecutive patients (mean age, 66 years; 38% female were referred for pre-operative CMR. Abnormal RVEF and LVEF were considered 30 days outcomes included, cardiac re-hospitalization, worsening congestive heart failure and mortality. Mean clinical follow up was 14 months.Forty-eight patients had reduced RVEF (mean 25% and 61 patients had normal RVEF (mean 50% (p<0.001. Fifty-four patients had reduced LVEF (mean 30% and 55 patients had normal LVEF (mean 59% (p<0.001. Patients with reduced RVEF had a higher incidence of long-term cardiac re-hospitalization vs. patients with normal RVEF (31% vs.13%, p<0.05. Abnormal RVEF was a predictor for long-term cardiac re-hospitalization (HR 3.01 [CI 1.5-7.9], p<0.03. Reduced LVEF did not influence long-term cardiac re-hospitalization.Abnormal RVEF is a stronger predictor for long-term cardiac re-hospitalization than abnormal LVEF in patients undergoing isolated CABG and valve procedures.

  6. Reduced Right Ventricular Function Predicts Long-Term Cardiac Re-Hospitalization after Cardiac Surgery.

    Science.gov (United States)

    Lella, Leela K; Sales, Virna L; Goldsmith, Yulia; Chan, Jacqueline; Iskandir, Marina; Gulkarov, Iosif; Tortolani, Anthony; Brener, Sorin J; Sacchi, Terrence J; Heitner, John F

    2015-01-01

    The significance of right ventricular ejection fraction (RVEF), independent of left ventricular ejection fraction (LVEF), following isolated coronary artery bypass grafting (CABG) and valve procedures remains unknown. The aim of this study is to examine the significance of abnormal RVEF by cardiac magnetic resonance (CMR), independent of LVEF in predicting outcomes of patients undergoing isolated CABG and valve surgery. From 2007 to 2009, 109 consecutive patients (mean age, 66 years; 38% female) were referred for pre-operative CMR. Abnormal RVEF and LVEF were considered hospitalizations and early mortaility; long-term (> 30 days) outcomes included, cardiac re-hospitalization, worsening congestive heart failure and mortality. Mean clinical follow up was 14 months. Forty-eight patients had reduced RVEF (mean 25%) and 61 patients had normal RVEF (mean 50%) (plong-term cardiac re-hospitalization vs. patients with normal RVEF (31% vs.13%, plong-term cardiac re-hospitalization (HR 3.01 [CI 1.5-7.9], plong-term cardiac re-hospitalization. Abnormal RVEF is a stronger predictor for long-term cardiac re-hospitalization than abnormal LVEF in patients undergoing isolated CABG and valve procedures.

  7. Psychometric validation of the cardiac rehabilitation barriers scale.

    Science.gov (United States)

    Shanmugasegaram, Shamila; Gagliese, Lucia; Oh, Paul; Stewart, Donna E; Brister, Stephanie J; Chan, Victoria; Grace, Sherry L

    2012-02-01

    The purpose of this study was to investigate the factor structure and psychometric properties of the Cardiac Rehabilitation Barriers Scale (CRBS). In total, 2636 cardiac inpatients from 11 hospitals completed a survey. One year later, participants completed a follow-up survey, which included the CRBS. A subsample of patients also completed a third survey which included the CRBS, the Cardiac Rehabilitation Enrolment Obstacles scale, and the Beliefs About Cardiac Rehabilitation scale three weeks later. The CRBS asked participants to rate 21 cardiac rehabilitation barriers on a five-point Likert scale regardless of cardiac rehabilitation referral or enrolment. Maximum likelihood factor analysis with oblique rotation resulted in a four-factor solution: perceived need/healthcare factors (eigenvalue = 6.13, Cronbach's α = .89), logistical factors (eigenvalue = 5.83, Cronbach's α = .88), work/time conflicts (eigenvalue = 3.78, Cronbach's α = .71), and comorbidities/functional status (eigenvalue = 4.85, Cronbach's α = .83). Mean total perceived barriers were significantly greater among non-enrollees than cardiac rehabilitation enrollees (P scales was also demonstrated. Test-retest reliability of the CRBS was acceptable (intraclass correlation coefficient = .64). The CRBS consists of four subscales and has sound psychometric properties. The extent to which identified barriers can be addressed to facilitate greater cardiac rehabilitation utilization warrants future study.

  8. Overexpression of Catalase Diminishes Oxidative Cysteine Modifications of Cardiac Proteins.

    Directory of Open Access Journals (Sweden)

    Chunxiang Yao

    Full Text Available Reactive protein cysteine thiolates are instrumental in redox regulation. Oxidants, such as hydrogen peroxide (H2O2, react with thiolates to form oxidative post-translational modifications, enabling physiological redox signaling. Cardiac disease and aging are associated with oxidative stress which can impair redox signaling by altering essential cysteine thiolates. We previously found that cardiac-specific overexpression of catalase (Cat, an enzyme that detoxifies excess H2O2, protected from oxidative stress and delayed cardiac aging in mice. Using redox proteomics and systems biology, we sought to identify the cysteines that could play a key role in cardiac disease and aging. With a 'Tandem Mass Tag' (TMT labeling strategy and mass spectrometry, we investigated differential reversible cysteine oxidation in the cardiac proteome of wild type and Cat transgenic (Tg mice. Reversible cysteine oxidation was measured as thiol occupancy, the ratio of total available versus reversibly oxidized cysteine thiols. Catalase overexpression globally decreased thiol occupancy by ≥1.3 fold in 82 proteins, including numerous mitochondrial and contractile proteins. Systems biology analysis assigned the majority of proteins with differentially modified thiols in Cat Tg mice to pathways of aging and cardiac disease, including cellular stress response, proteostasis, and apoptosis. In addition, Cat Tg mice exhibited diminished protein glutathione adducts and decreased H2O2 production from mitochondrial complex I and II, suggesting improved function of cardiac mitochondria. In conclusion, our data suggest that catalase may alleviate cardiac disease and aging by moderating global protein cysteine thiol oxidation.

  9. Overexpression of Catalase Diminishes Oxidative Cysteine Modifications of Cardiac Proteins.

    Science.gov (United States)

    Yao, Chunxiang; Behring, Jessica B; Shao, Di; Sverdlov, Aaron L; Whelan, Stephen A; Elezaby, Aly; Yin, Xiaoyan; Siwik, Deborah A; Seta, Francesca; Costello, Catherine E; Cohen, Richard A; Matsui, Reiko; Colucci, Wilson S; McComb, Mark E; Bachschmid, Markus M

    2015-01-01

    Reactive protein cysteine thiolates are instrumental in redox regulation. Oxidants, such as hydrogen peroxide (H2O2), react with thiolates to form oxidative post-translational modifications, enabling physiological redox signaling. Cardiac disease and aging are associated with oxidative stress which can impair redox signaling by altering essential cysteine thiolates. We previously found that cardiac-specific overexpression of catalase (Cat), an enzyme that detoxifies excess H2O2, protected from oxidative stress and delayed cardiac aging in mice. Using redox proteomics and systems biology, we sought to identify the cysteines that could play a key role in cardiac disease and aging. With a 'Tandem Mass Tag' (TMT) labeling strategy and mass spectrometry, we investigated differential reversible cysteine oxidation in the cardiac proteome of wild type and Cat transgenic (Tg) mice. Reversible cysteine oxidation was measured as thiol occupancy, the ratio of total available versus reversibly oxidized cysteine thiols. Catalase overexpression globally decreased thiol occupancy by ≥1.3 fold in 82 proteins, including numerous mitochondrial and contractile proteins. Systems biology analysis assigned the majority of proteins with differentially modified thiols in Cat Tg mice to pathways of aging and cardiac disease, including cellular stress response, proteostasis, and apoptosis. In addition, Cat Tg mice exhibited diminished protein glutathione adducts and decreased H2O2 production from mitochondrial complex I and II, suggesting improved function of cardiac mitochondria. In conclusion, our data suggest that catalase may alleviate cardiac disease and aging by moderating global protein cysteine thiol oxidation.

  10. Focused cardiac ultrasound is feasible in the general practice setting and alters diagnosis and management of cardiac disease

    Directory of Open Access Journals (Sweden)

    James Yates

    2016-08-01

    Full Text Available Background: Ultrasound-assisted examination of the cardiovascular system with focused cardiac ultrasound by the treating physician is non-invasive and changes diagnosis and management of patient’s with suspected cardiac disease. This has not been reported in a general practice setting. Aim: To determine whether focused cardiac ultrasound performed on patients aged over 50 years changes the diagnosis and management of cardiac disease by a general practitioner. Design and setting: A prospective observational study of 80 patients aged over 50 years and who had not received echocardiography or chest CT within 12 months presenting to a general practice. Method: Clinical assessment and management of significant cardiac disorders in patients presenting to general practitioners were recorded before and after focused cardiac ultrasound. Echocardiography was performed by a medical student with sufficient training, which was verified by an expert. Differences in diagnosis and management between conventional and ultrasound-assisted assessment were recorded. Results and conclusion: Echocardiography and interpretation were acceptable in all patients. Significant cardiac disease was detected in 16 (20% patients, including aortic stenosis in 9 (11% and cardiac failure in 7 (9%, which were missed by clinical examination in 10 (62.5% of these patients. Changes in management occurred in 12 patients (15% overall and 75% of those found to have significant cardiac disease including referral for diagnostic echocardiography in 8 (10%, commencement of heart failure treatment in 3 (4% and referral to a cardiologist in 1 patient (1%. Routine focused cardiac ultrasound is feasible and frequently alters the diagnosis and management of cardiac disease in patients aged over 50 years presenting to a general practice.

  11. A study of potential output and output gap in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Václav Adamec

    2012-01-01

    Full Text Available Analysis of economic cycle is of enormous importance for monitoring economic output and explaining price and wage inflation. It provides essential information for shaping economic and monetary policy of central authorities. Several methods are currently available to estimate potential output and output gap. In the current study, methods of Hodrick-Prescott filter and Cobb-Douglas production function were implemented to estimate potential output, which cannot be empirically observed. For the purpose of comparing the above methods, quarterly and annual time series of real GDP, labour and gross fixed capital starting in 1996 were used for estimation of the output gap. Relative contributions of labour, fixed capital formation and technology improvement factor towards growth of potential output were quantified for the studied series. The Cobb-Douglas production function appears to be superior to Hodrick-Prescott filter in providing quality estimates of potential output. Hodrick-Prescott filter allows estimation of potential output; nevertheless, it fails to identify components of cyclic behaviour of economic activity. Cobb-Douglas production function describes level of potential product assuming average utilization of production factors. A detailed analysis of components of economic growth in the observed period is provided.

  12. Histamine induces postprandian tachycardia through a direct effect on cardiac H2-receptors in pythons

    DEFF Research Database (Denmark)

    Jensen, Nini Skovgaard; Møller, Kate; Gesser, Hans

    2009-01-01

    The intrinsic heart rate of most vertebrates studied, including humans, is elevated during digestion, suggesting that a non-adrenergic-non-cholinergic factor contributes to the postprandial tachycardia. The regulating factor, however, remains elusive and difficult to identify. Pythons can ingest...... very large meals and digestion is associated with a marked rise in metabolism that is sustained for several days. The metabolic rise causes more than a doubling of heart rate and a four-fold rise in cardiac output. This makes the python an interesting model to investigate the postprandial tachycardia....... We measured blood pressure and heart rate in fasting Python regius, and at 24 and 48h after ingestion of a meal amounting to 25% of body weight. Digestion caused heart rate to increase from 25 to 56 min-1 while blood pressure was unchanged. The postprandial rise in heart rate was partially due...

  13. Industrial input-output analysis: implications for industrial ecology.

    Science.gov (United States)

    Duchin, F

    1992-02-01

    Industrial ecology will need to develop fundamentally new approaches to reducing, reusing, and recycling wastes. Industrial ecology will also require an analytic framework for examining the implications for the economic system as a whole of each potential web of industrial changes. A suitable framework is furnished by structural economics, which situates the economy within the physical world. This approach is based on dynamic analysis rather than static concepts of equilibrium, and optimization assumptions are used selectively rather than as the general solution mechanism. Input-output economics, an important formal model within structural economics, can trace the stocks and flows of energy and other materials from extraction through production and consumption to recycling or disposal. An input-output computation, including wastes, is presented; it illustrates the separate but integrated analysis of physical stocks and flows and of prices and costs. This paper also describes the major advances that have been made in the last decade in the extension of input-output economics to address increasingly complex questions, notably the fully dynamic physical/price/income model and the engineering/input-output data base. Economists need to be able to assess the costs of cleaning up and to develop incentive schemes to increase the likelihood this will happen. To do this, economists need to take on the difficult "how" questions that concern industrial ecologists since the cost, and indeed the wider implications, of cleaning up depends upon how it is done. Structural economics, and modern input-output models and data bases, in particular, can help meet this challenge.

  14. Eating marshmallows reduces ileostomy output: a randomized crossover trial.

    Science.gov (United States)

    Clarebrough, E; Guest, G; Stupart, D

    2015-12-01

    Anecdotally, many ostomates believe that eating marshmallows can reduce ileostomy effluent. There is a plausible mechanism for this, as the gelatine contained in marshmallows may thicken small bowel fluid, but there is currently no evidence that this is effective. This was a randomized crossover trial. Adult patients with well-established ileostomies were included. Ileostomy output was measured for 1 week during which three marshmallows were consumed three times daily, and for one control week where marshmallows were not eaten. There was a 2-day washout period. Patients were randomly allocated to whether the control or intervention week occurred first. In addition, a questionnaire was administered regarding patient's subjective experience of their ileostomy function. Thirty-one participants were recruited; 28 completed the study. There was a median reduction in ileostomy output volume of 75 ml per day during the study period (P = 0.0054, 95% confidence interval 23.4-678.3) compared with the control week. Twenty of 28 subjects (71%) experienced a reduction in their ileostomy output, two had no change and six reported an increase. During the study period, participants reported fewer ileostomy bag changes (median five per day vs six in the control period, P = 0.0255). Twenty of 28 (71%) reported that the ileostomy effluent was thicker during the study week (P = 0.023). Overall 19 (68%) participants stated they would use marshmallows in the future if they wanted to reduce or thicken their ileostomy output. Eating marshmallows leads to a small but statistically significant reduction in ileostomy output. Colorectal Disease © 2015 The Association of Coloproctology of Great Britain and Ireland.

  15. Bigger is not better: cortisol-induced cardiac growth and dysfunction in salmonids

    DEFF Research Database (Denmark)

    Johansen, Ida B.; Sandblom, Erik; Skov, Peter Vilhelm

    2017-01-01

    Stress and elevated cortisol levels are associated with pathological heart growth and cardiovascular disease in humans and other mammals. We recently established a link between heritable variation in post-stress cortisol production and cardiac growth in salmonid fish too. A conserved stimulatory...... effect of the otherwise catabolic steroid hormone cortisol is probably implied, but has to date not been established experimentally. Furthermore, whereas cardiac growth is associated with failure of the mammalian heart, pathological cardiac hypertrophy has not previously been described in fish. Here, we...... show that rainbow trout (Oncorhynchus mykiss) treated with cortisol in the diet for 45 days have enlarged hearts with lower maximum stroke volume and cardiac output. In accordance with impaired cardiac performance, overall circulatory oxygen-transporting capacity was diminished as indicated by reduced...

  16. Opening the "Black Box" of efficiency measurement : Input allocation in multi-output settings

    NARCIS (Netherlands)

    Dierynck, B.; Cherchye, L.J.H.; Sabbe, J.; Roodhooft, F.; de Rock, B.

    2013-01-01

    We develop a new data envelopment analysis (DEA)-based methodology for measuring the efficiency of decision-making units (DMUs) characterized by multiple inputs and multiple outputs. The distinguishing feature of our method is that it explicitly includes information about output-specific inputs and

  17. Research Output, Socialization, and the Biglan Model.

    Science.gov (United States)

    Creswell, John W.; Bean, John P.

    1981-01-01

    A test of the Biglan model of faculty subcultures using measures of research output and tests of the model controlling for the effects of faculty socialization are described. The Biglan model is found to be valid, and the distinctiveness of the Biglan groups appears to increase with the socialization of faculty into subject areas. (Author/MLW)

  18. What shapes output of policy reform?

    DEFF Research Database (Denmark)

    Carlsen, Kirsten

    This thesis deals with the factors shaping forest policy output during the stages implementation and bases its main message on empirical findings from the forestry sector in Ghana. Policy and institutional factors are important underlying causes for deforestation, especially in the tropics. Fores...

  19. THE MALARIA BURDEN AND AGRICULTURAL OUTPUT IN ...

    African Journals Online (AJOL)

    iya beji

    This together with evidence from other related studies suggest that the agricultural sector bears about 75 per cent of the direct economic burden of malaria in. Nigeria. This translates to about 3 per cent of the real GDP that is lost annually in agricultural outputs to the malaria disease. This being the case, the government is.

  20. Output formatting in Apple-Soft Basic

    International Nuclear Information System (INIS)

    Navale, A.S.

    1987-01-01

    Personal computers are being used extensively in various fields. BASIC is a very popular and widely used language in personal computers. Apple computer is one of the popular machines used for scientific and engineering applications. Presenting output from computers in a neat and easy to read form is very important. Languages like FORTRAN have utility command 'FORMAT' which takes care of the formatting of the output in user-defined form. In some versions of BASIC a PRINT USING facility is available but it is not as powerful as the FORTRAN statement 'FORMAT'. Applesoft basic does not have even this PRINT USING command. Programmers have to write their own program segments to handle output formatting in Applesoft BASIC. Generally, such user written programs are of limited use as they cannot be used easily with other programs. A general purpose and easily transportable subroutine in Applesoft BASIC is presented here for handling output formatting in user-defined structure. The subroutine is nearly as powerful as the FORMAT statement in FORTRAN. It can also be used in other versions of BASIC with very little modifications. 3 tables, 4 refs. (author)

  1. Explaining output volatility: The case of taxation

    DEFF Research Database (Denmark)

    Posch, Olaf

    This paper studies the effects of taxation on output volatility in OECD countries to shed light on the sources of observed heterogeneity over time and across countries. To this end, we derive tax effects on macro aggregates in a stochastic neoclassical model. As a result, taxes are shown to affect...

  2. H∞ output-feedback fuzzy proportional-integral control of fully delayed input/output systems.

    Science.gov (United States)

    Chiu, Chian-Song; Chiang, Tung-Sheng

    2017-01-01

    This paper presents the output-feedback fuzzy proportional-integral (PI) controller design for uncertain nonlinear systems with both fully delayed input and output. Based on the Takagi-Sugeno (T-S) fuzzy model representation, the output-feedback PI control is realized via parallel distributed PI compensation and novel LMI gain design. Although the T-S fuzzy PI controller is simple, asymptotic output regulation is assured to overcome the effect of uncertainty, state delay, and full input/output delays. When considering disturbance and measurement noise, the control performance is achieved by robust gain design. Furthermore, state observers and bilinear matrix inequality conditions are removed in this paper. Finally, time-delay Chua׳s circuit system and a continuous-time stirred tank reactor are taken as applications to show the expected performance. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  3. Cardiac effects of electrical stun guns: does position of barbs contact make a difference?

    Science.gov (United States)

    Lakkireddy, Dhanunjaya; Wallick, Donald; Verma, Atul; Ryschon, Kay; Kowalewski, William; Wazni, Oussama; Butany, Jagdish; Martin, David; Tchou, Patrick J

    2008-04-01

    The use of electrical stun guns has been rising among law enforcement authorities for subduing violent subjects. Multiple reports have raised concerns over their safety. The cardiovascular safety profile of these devices in relationship to the position of delivery on the torso has not been well studied. We tested 13 adult pigs using a custom device built to deliver neuromuscular incapacitating (NMI) discharge of increasing intensity that matched the waveform of a commercially available stun gun (TASER(R) X-26, TASER International, Scottsdale, AZ, USA). Discharges with increasing multiples of output capacitances were applied in a step-up and step-down fashion, using two-tethered barbs at five locations: (1) Sternal notch to cardiac apex (position-1), (2) sternal notch to supraumbilical area (position-2), (3) sternal notch to infraumbilical area (position-3), (4) side to side on the chest (position-4), and (5) upper to lower mid-posterior torso (position-5). Endpoints included determination of maximum safe multiple (MaxSM), ventricular fibrillation threshold (VFT), and minimum ventricular fibrillation induction multiple (MinVFIM). Standard TASER discharges repeated three times did not cause ventricular fibrillation (VF) at any of the five locations. When the barbs were applied in the axis of the heart (position-1), MaxSM and MinVFIM were significantly lower than when applied away from the heart, on the dorsum (position-5) (4.31 +/- 1.11 vs 40.77 +/- 9.54, P< 0.001 and 8.31 +/- 2.69 vs 50.77 +/- 9.54, P< 0.001, respectively). The values of these endpoints at position-2, position-3, and position-4 were progressively higher and ranged in between those of position-1 and position-5. Presence of ventricular capture at a 2:1 ratio to the delivered TASER impulses correlated with induction of VF. No significant metabolic changes were seen after standard NMI TASER discharge. There was no evidence of myocardial damage based on serum cardiac markers, electrocardiography

  4. Blunt cardiac trauma: lessons learned from the medical examiner.

    Science.gov (United States)

    Teixeira, Pedro G R; Georgiou, Chrysanthos; Inaba, Kenji; Dubose, Joseph; Plurad, David; Chan, Linda S; Toms, Carla; Noguchi, Thomas T; Demetriades, Demetrios

    2009-12-01

    The objective of this study was to analyze autopsy findings after blunt traumatic deaths to identify the incidence of cardiac injuries and describe the patterns of associated injuries. All autopsies performed by the Los Angeles County Forensic Medicine Division for blunt traumatic deaths in 2005 were retrospectively reviewed. Only cases that underwent a full autopsy including internal examination were included in the analysis. The study population was divided into two groups according to the presence or absence of a cardiac injury and compared for differences in baseline characteristics and types of associated injuries. Of the 881 fatal victims of blunt trauma received by the Los Angeles County Forensic Medicine Division, 304 (35%) underwent a full autopsy with internal examination and were included in the analysis. The mean age was 43 years +/- 21 years, patients were more often men (71%) and were intoxicated in 39% of the cases. The most common mechanism was motor vehicle collision (50%), followed by pedestrian struck by auto (37%), and 32% had a cardiac injury. Death at the scene was significantly more common in patients with a cardiac injury (78% vs. 65%, p = 0.02). The right chambers were the most frequently injured (30%, right atrium; 27%, right ventricle). Among the 96 patients with cardiac injuries, 64% had transmural rupture. Multiple chambers were ruptured in 26%, the right atrium in 25%, and the right ventricle in 20% of these patients. Patients with cardiac injuries were significantly more likely to have other associated injuries: thoracic aorta (47% vs. 27%, p = 0.001), hemothorax (81% vs. 59%, p injury (77% vs. 48%, p cardiac injury. Of the 96 patients with a cardiac injury, 78% died at the scene of the crash and 22% died en route or at the hospital. Cardiac injury is a common autopsy finding after blunt traumatic fatalities, with the majority of deaths occurring at the scene. Patients with cardiac injuries are at significantly increased risk for

  5. Hypothyroidism and its rapid correction alter cardiac remodeling.

    Directory of Open Access Journals (Sweden)

    Georges Hajje

    Full Text Available The cardiovascular effects of mild and overt thyroid disease include a vast array of pathological changes. As well, thyroid replacement therapy has been suggested for preserving cardiac function. However, the influence of thyroid hormones on cardiac remodeling has not been thoroughly investigated at the molecular and cellular levels. The purpose of this paper is to study the effect of hypothyroidism and thyroid replacement therapy on cardiac alterations. Thirty Wistar rats were divided into 2 groups: a control (n = 10 group and a group treated with 6-propyl-2-thiouracil (PTU (n = 20 to induce hypothyroidism. Ten of the 20 rats in the PTU group were then treated with L-thyroxine to quickly re-establish euthyroidism. The serum levels of inflammatory markers, such as C-reactive protein (CRP, tumor necrosis factor alpha (TNF-α, interleukin 6 (IL6 and pro-fibrotic transforming growth factor beta 1 (TGF-β1, were significantly increased in hypothyroid rats; elevations in cardiac stress markers, brain natriuretic peptide (BNP and cardiac troponin T (cTnT were also noted. The expressions of cardiac remodeling genes were induced in hypothyroid rats in parallel with the development of fibrosis, and a decline in cardiac function with chamber dilation was measured by echocardiography. Rapidly reversing the hypothyroidism and restoring the euthyroid state improved cardiac function with a decrease in the levels of cardiac remodeling markers. However, this change further increased the levels of inflammatory and fibrotic markers in the plasma and heart and led to myocardial cellular infiltration. In conclusion, we showed that hypothyroidism is related to cardiac function decline, fibrosis and inflammation; most importantly, the rapid correction of hypothyroidism led to cardiac injuries. Our results might offer new insights for the management of hypothyroidism-induced heart disease.

  6. Hypothyroidism and its rapid correction alter cardiac remodeling.

    Science.gov (United States)

    Hajje, Georges; Saliba, Youakim; Itani, Tarek; Moubarak, Majed; Aftimos, Georges; Farès, Nassim

    2014-01-01

    The cardiovascular effects of mild and overt thyroid disease include a vast array of pathological changes. As well, thyroid replacement therapy has been suggested for preserving cardiac function. However, the influence of thyroid hormones on cardiac remodeling has not been thoroughly investigated at the molecular and cellular levels. The purpose of this paper is to study the effect of hypothyroidism and thyroid replacement therapy on cardiac alterations. Thirty Wistar rats were divided into 2 groups: a control (n = 10) group and a group treated with 6-propyl-2-thiouracil (PTU) (n = 20) to induce hypothyroidism. Ten of the 20 rats in the PTU group were then treated with L-thyroxine to quickly re-establish euthyroidism. The serum levels of inflammatory markers, such as C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin 6 (IL6) and pro-fibrotic transforming growth factor beta 1 (TGF-β1), were significantly increased in hypothyroid rats; elevations in cardiac stress markers, brain natriuretic peptide (BNP) and cardiac troponin T (cTnT) were also noted. The expressions of cardiac remodeling genes were induced in hypothyroid rats in parallel with the development of fibrosis, and a decline in cardiac function with chamber dilation was measured by echocardiography. Rapidly reversing the hypothyroidism and restoring the euthyroid state improved cardiac function with a decrease in the levels of cardiac remodeling markers. However, this change further increased the levels of inflammatory and fibrotic markers in the plasma and heart and led to myocardial cellular infiltration. In conclusion, we showed that hypothyroidism is related to cardiac function decline, fibrosis and inflammation; most importantly, the rapid correction of hypothyroidism led to cardiac injuries. Our results might offer new insights for the management of hypothyroidism-induced heart disease.

  7. The pathogenesis of cardiac fibrosis.

    Science.gov (United States)

    Kong, Ping; Christia, Panagiota; Frangogiannis, Nikolaos G

    2014-02-01

    Cardiac fibrosis is characterized by net accumulation of extracellular matrix proteins in the cardiac interstitium, and contributes to both systolic and diastolic dysfunction in many cardiac pathophysiologic conditions. This review discusses the cellular effectors and molecular pathways implicated in the pathogenesis of cardiac fibrosis. Although activated myofibroblasts are the main effector cells in the fibrotic heart, monocytes/macrophages, lymphocytes, mast cells, vascular cells and cardiomyocytes may also contribute to the fibrotic response by secreting key fibrogenic mediators. Inflammatory cytokines and chemokines, reactive oxygen species, mast cell-derived proteases, endothelin-1, the renin/angiotensin/aldosterone system, matricellular proteins, and growth factors (such as TGF-β and PDGF) are some of the best-studied mediators implicated in cardiac fibrosis. Both experimental and clinical evidence suggests that cardiac fibrotic alterations may be reversible. Understanding the mechanisms responsible for initiation, progression, and resolution of cardiac fibrosis is crucial to design anti-fibrotic treatment strategies for patients with heart disease.

  8. NUCLEAR IMAGING IN THE DIAGNOSIS OF CARDIAC AMYLOIDOSIS

    Directory of Open Access Journals (Sweden)

    V. B. Sergienko

    2018-01-01

    Full Text Available Histological analysis of endomyocardial tissue is still the gold standard for the diagnosis of cardiac amyloidosis but has its limitations. Accordingly, there is a need for noninvasive techniques to cardiac amyloidosis diagnostics. Echocardiography and magnetic resonance imaging can show characteristics which may not be very specific for cardiac amyloid. Recently, new opportunities of nuclear imaging in risk stratification and assessment of prognosis for patients with cardiac amyloidosis have appeared. During the last two decades different classes of radiopharmaceuticals have been developed based on compounds tropic to the components of amyloid infiltrates. In this paper we describe the current possibilities and perspectives of nuclear medicine techniques in patients with cardiac amyloidosis, including osteotropic and neurotropic scintigraphy, single-photon and positron emission tomography

  9. [Cardiac sarcoidosis: diagnostics, treatment and follow-up].

    Science.gov (United States)

    Dudziak, Maria; Jankowska, Hanna; Dorniak, Karolina

    2018-03-27

    Sarcoidosis is a generalised granulomatous disorder of unknown aetiology. Cardiac involvement may affect conduction system, myocardium, valvular apparatus and pericardium. Clinical spectrum ranges from asymptomatic involvement to sudden cardiac death. Patients with biopsy-proven extracardiac sarcoidosis should be screened for cardiac involvement (standard ECG, 24-hour Holter ECG, echocardiography) and in case of any abnormalities found on these tests, more advanced diagnostic methods should be used. Steroid treatment is still the mainstay of therapy in cardiac sarcoidosis. Several immunosuppresive agents are also effective and used in different combinations with steroids, as well as heart failure treatment (including ACE inhibitors, angiotensin receptor blockers, beta-blockers and diuretics). Advanced heart block requires pacemaker implantation, and implantable cardioverterdefibrillator is an effective treatment in primary and secondary prophylaxis of sudden cardiac death. Heart transplantation is considered in advanced, drug-resistant heart failure or incessant ventricular arrhythmias unresponsive to other forms of therapy. © 2018 MEDPRESS.

  10. A case of thyroid storm with cardiac arrest

    Directory of Open Access Journals (Sweden)

    Nakashima Y

    2014-05-01

    Full Text Available Yutaka Nakashima,1 Tsuneaki Kenzaka,2 Masanobu Okayama,3 Eiji Kajii31Department for Support of Rural Medicine, Yamaguchi Grand Medical Center, 2Division of General Medicine, Center for Community Medicine, Jichi Medical University School of Medicine, Shimotsuke, Japan; 3Division of Community and Family Medicine, Center for Community Medicine, Jichi Medical University School of Medicine, Shimotsuke, JapanAbstract: A 23-year-old man became unconscious while jogging. He immediately received basic life support from a bystander and was transported to our hospital. On arrival, his spontaneous circulation had returned from a state of ventricular fibrillation and pulseless electrical activity. Following admission, hyperthyroidism led to a suspicion of thyroid storm, which was then diagnosed as a possible cause of the cardiac arrest. Although hyperthyroidism-induced cardiac arrest including ventricular fibrillation is rare, it should be considered when diagnosing the cause of treatable cardiac arrest.Keywords: hyperthyroidism, ventricular fibrillation, treatable cardiac arrest, cardiac arrest, cardiopulmonary arrest

  11. Predictive Models for Normal Fetal Cardiac Structures.

    Science.gov (United States)

    Krishnan, Anita; Pike, Jodi I; McCarter, Robert; Fulgium, Amanda L; Wilson, Emmanuel; Donofrio, Mary T; Sable, Craig A

    2016-12-01

    Clinicians rely on age- and size-specific measures of cardiac structures to diagnose cardiac disease. No universally accepted normative data exist for fetal cardiac structures, and most fetal cardiac centers do not use the same standards. The aim of this study was to derive predictive models for Z scores for 13 commonly evaluated fetal cardiac structures using a large heterogeneous population of fetuses without structural cardiac defects. The study used archived normal fetal echocardiograms in representative fetuses aged 12 to 39 weeks. Thirteen cardiac dimensions were remeasured by a blinded echocardiographer from digitally stored clips. Studies with inadequate imaging views were excluded. Regression models were developed to relate each dimension to estimated gestational age (EGA) by dates, biparietal diameter, femur length, and estimated fetal weight by the Hadlock formula. Dimension outcomes were transformed (e.g., using the logarithm or square root) as necessary to meet the normality assumption. Higher order terms, quadratic or cubic, were added as needed to improve model fit. Information criteria and adjusted R 2 values were used to guide final model selection. Each Z-score equation is based on measurements derived from 296 to 414 unique fetuses. EGA yielded the best predictive model for the majority of dimensions; adjusted R 2 values ranged from 0.72 to 0.893. However, each of the other highly correlated (r > 0.94) biometric parameters was an acceptable surrogate for EGA. In most cases, the best fitting model included squared and cubic terms to introduce curvilinearity. For each dimension, models based on EGA provided the best fit for determining normal measurements of fetal cardiac structures. Nevertheless, other biometric parameters, including femur length, biparietal diameter, and estimated fetal weight provided results that were nearly as good. Comprehensive Z-score results are available on the basis of highly predictive models derived from gestational

  12. Pump apparatus including deconsolidator

    Energy Technology Data Exchange (ETDEWEB)

    Sonwane, Chandrashekhar; Saunders, Timothy; Fitzsimmons, Mark Andrew

    2014-10-07

    A pump apparatus includes a particulate pump that defines a passage that extends from an inlet to an outlet. A duct is in flow communication with the outlet. The duct includes a deconsolidator configured to fragment particle agglomerates received from the passage.

  13. Hemodynamics driven cardiac valve morphogenesis.

    Science.gov (United States)

    Steed, Emily; Boselli, Francesco; Vermot, Julien

    2016-07-01

    Mechanical forces are instrumental to cardiovascular development and physiology. The heart beats approximately 2.6 billion times in a human lifetime and heart valves ensure that these contractions result in an efficient, unidirectional flow of the blood. Composed of endocardial cells (EdCs) and extracellular matrix (ECM), cardiac valves are among the most mechanically challenged structures of the body both during and after their development. Understanding how hemodynamic forces modulate cardiovascular function and morphogenesis is key to unraveling the relationship between normal and pathological cardiovascular development and physiology. Most valve diseases have their origins in embryogenesis, either as signs of abnormal developmental processes or the aberrant re-expression of fetal gene programs normally quiescent in adulthood. Here we review recent discoveries in the mechanobiology of cardiac valve development and introduce the latest technologies being developed in the zebrafish, including live cell imaging and optical technologies, as well as modeling approaches that are currently transforming this field. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel. Copyright © 2015. Published by Elsevier B.V.

  14. Cardiac fusion and complex congenital cardiac defects in thoracopagus twins: diagnostic value of cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Park, Jeong-Jun [University of Ulsan College of Medicine, Asan Medical Center, Department of Pediatric Cardiac Surgery, Seoul (Korea, Republic of); Kim, Ellen Ai-Rhan [University of Ulsan College of Medicine, Asan Medical Center, Division of Neonatology, Department of Pediatrics, Seoul (Korea, Republic of); Won, Hye-Sung [University of Ulsan College of Medicine, Asan Medical Center, Department of Obstetrics and Gynecology, Seoul (Korea, Republic of)

    2014-09-15

    Most thoracopagus twins present with cardiac fusion and associated congenital cardiac defects, and assessment of this anatomy is of critical importance in determining patient care and outcome. Cardiac CT with electrocardiographic triggering provides an accurate and quick morphological assessment of both intracardiac and extracardiac structures in newborns, making it the best imaging modality to assess thoracopagus twins during the neonatal period. In this case report, we highlight the diagnostic value of cardiac CT in thoracopagus twins with an interatrial channel and complex congenital cardiac defects. (orig.)

  15. Output feedback control of a quadrotor UAV using neural networks.

    Science.gov (United States)

    Dierks, Travis; Jagannathan, Sarangapani

    2010-01-01

    In this paper, a new nonlinear controller for a quadrotor unmanned aerial vehicle (UAV) is proposed using neural networks (NNs) and output feedback. The assumption on the availability of UAV dynamics is not always practical, especially in an outdoor environment. Therefore, in this work, an NN is introduced to learn the complete dynamics of the UAV online, including uncertain nonlinear terms like aerodynamic friction and blade flapping. Although a quadrotor UAV is underactuated, a novel NN virtual control input scheme is proposed which allows all six degrees of freedom (DOF) of the UAV to be controlled using only four control inputs. Furthermore, an NN observer is introduced to estimate the translational and angular velocities of the UAV, and an output feedback control law is developed in which only the position and the attitude of the UAV are considered measurable. It is shown using Lyapunov theory that the position, orientation, and velocity tracking errors, the virtual control and observer estimation errors, and the NN weight estimation errors for each NN are all semiglobally uniformly ultimately bounded (SGUUB) in the presence of bounded disturbances and NN functional reconstruction errors while simultaneously relaxing the separation principle. The effectiveness of proposed output feedback control scheme is then demonstrated in the presence of unknown nonlinear dynamics and disturbances, and simulation results are included to demonstrate the theoretical conjecture.

  16. Magnetic resonance imaging in patients with cardiac pacemakers: era of "MR Conditional" designs

    Directory of Open Access Journals (Sweden)

    Shellock Frank G

    2011-10-01

    Full Text Available Abstract Advances in cardiac device technology have led to the first generation of magnetic resonance imaging (MRI conditional devices, providing more diagnostic imaging options for patients with these devices, but also new controversies. Prior studies of pacemakers in patients undergoing MRI procedures have provided groundwork for design improvements. Factors related to magnetic field interactions and transfer of electromagnetic energy led to specific design changes. Ferromagnetic content was minimized. Reed switches were modified. Leads were redesigned to reduce induced currents/heating. Circuitry filters and shielding were implemented to impede or limit the transfer of certain unwanted electromagnetic effects. Prospective multicenter clinical trials to assess the safety and efficacy of the first generation of MR conditional cardiac pacemakers demonstrated no significant alterations in pacing parameters compared to controls. There were no reported complications through the one month visit including no arrhythmias, electrical reset, inhibition of generator output, or adverse sensations. The safe implementation of these new technologies requires an understanding of the well-defined patient and MR system conditions. Although scanning a patient with an MR conditional device following the strictly defined patient and MR system conditions appears straightforward, issues related to patients with pre-existing devices remain complex. Until MR conditional devices are the routine platform for all of these devices, there will still be challenging decisions regarding imaging patients with pre-existing devices where MRI is required to diagnose and manage a potentially life threatening or serious scenario. A range of other devices including ICDs, biventricular devices, and implantable physiologic monitors as well as guidance of medical procedures using MRI technology will require further biomedical device design changes and testing. The development and

  17. Jet and ultrasonic nebuliser output: use of a new method for direct measurement of aerosol output.

    Science.gov (United States)

    Dennis, J H; Stenton, S C; Beach, J R; Avery, A J; Walters, E H; Hendrick, D J

    1990-10-01

    Output from jet nebulisers is calibrated traditionally by weighing them before and after nebulisation, but the assumption that the weight difference is a close measure of aerosol generation could be invalidated by the concomitant process of evaporation. A method has been developed for measuring aerosol output directly by using a solute (fluoride) tracer and aerosol impaction, and this has been compared with the traditional weight loss method for two Wright, six Turbo, and four Micro-Cirrus jet nebulisers and two Microinhaler ultrasonic nebulisers. The weight loss method overestimated true aerosol output for all jet nebulisers. The mean aerosol content, expressed as a percentage of the total weight loss, varied from as little as 15% for the Wright jet nebulisers to 54% (range 45-61%) for the Turbo and Micro-Cirrus jet nebulisers under the operating conditions used. In contrast, there was no discrepancy between weight loss and aerosol output for the ultrasonic nebulisers. These findings, along with evidence of both concentrating and cooling effects from jet nebulisation, confirm that total output from jet nebulisers contains two distinct fractions, vapour and aerosol. The vapour fraction, but not the aerosol fraction, was greatly influenced by reservoir temperature within the nebuliser; so the ratio of aerosol output to total weight loss varied considerably with temperature. It is concluded that weight loss is an inappropriate method of calibrating jet nebuliser aerosol output, and that this should be measured directly.

  18. Regression of Pathological Cardiac Hypertrophy: Signaling Pathways and Therapeutic Targets

    Science.gov (United States)

    Hou, Jianglong; Kang, Y. James

    2012-01-01

    Pathological cardiac hypertrophy is a key risk factor for heart failure. It is associated with increased interstitial fibrosis, cell death and cardiac dysfunction. The progression of pathological cardiac hypertrophy has long been considered as irreversible. However, recent clinical observations and experimental studies have produced evidence showing the reversal of pathological cardiac hypertrophy. Left ventricle assist devices used in heart failure patients for bridging to transplantation not only improve peripheral circulation but also often cause reverse remodeling of the geometry and recovery of the function of the heart. Dietary supplementation with physiologically relevant levels of copper can reverse pathological cardiac hypertrophy in mice. Angiogenesis is essential and vascular endothelial growth factor (VEGF) is a constitutive factor for the regression. The action of VEGF is mediated by VEGF receptor-1, whose activation is linked to cyclic GMP-dependent protein kinase-1 (PKG-1) signaling pathways, and inhibition of cyclic GMP degradation leads to regression of pathological cardiac hypertrophy. Most of these pathways are regulated by hypoxia-inducible factor. Potential therapeutic targets for promoting the regression include: promotion of angiogenesis, selective enhancement of VEGF receptor-1 signaling pathways, stimulation of PKG-1 pathways, and sustention of hypoxia-inducible factor transcriptional activity. More exciting insights into the regression of pathological cardiac hypertrophy are emerging. The time of translating the concept of regression of pathological cardiac hypertrophy to clinical practice is coming. PMID:22750195

  19. Apelin/APJ system: A bifunctional target for cardiac hypertrophy.

    Science.gov (United States)

    Lu, Liqun; Wu, Di; Li, Lanfang; Chen, Linxi

    2017-03-01

    Apelin acts as the endogenous ligand of G protein coupled receptors APJ. The apelin/APJ system is responsible for the occurrence and development of cardiovascular diseases. In recent years, apelin/APJ has been considered to play an important role in cardiac hypertrophy, but whether that role is beneficial or aggravating remains controversial. Apelin/APJ alleviates cardiac hypertrophy which is triggered by angiotensin II, oxidative stress and exercise. However, central administration of apelin induces cardiac hypertrophy. Peripheral administration of apelin also promotes the development of cardiac hypertrophy under non-pathological conditions. Furthermore, our laboratory discovers that apelin/APJ is able to induce hypertrophy of cardiomyocytes in vitro. The exact mechanism of apelin/APJ's dual effects in cardiac hypertrophy requires further study. In this paper, we review the controversies associated with apelin/APJ in cardiac hypertrophy and we elaborate the role of apelin/APJ in cardiac hypertrophy related-diseases including obesity, diabetes, hypertension, myocarditis and myocardial infarction. We conclude that further studies should emphasize more about the relationship between apelin/APJ and pathological hypertrophy especially in clinical patients. Moreover, apelin/APJ can be a promising therapeutic target for cardiac hypertrophy. Copyright © 2016. Published by Elsevier B.V.

  20. Regression of pathological cardiac hypertrophy: signaling pathways and therapeutic targets.

    Science.gov (United States)

    Hou, Jianglong; Kang, Y James

    2012-09-01

    Pathological cardiac hypertrophy is a key risk factor for heart failure. It is associated with increased interstitial fibrosis, cell death and cardiac dysfunction. The progression of pathological cardiac hypertrophy has long been considered as irreversible. However, recent clinical observations and experimental studies have produced evidence showing the reversal of pathological cardiac hypertrophy. Left ventricle assist devices used in heart failure patients for bridging to transplantation not only improve peripheral circulation but also often cause reverse remodeling of the geometry and recovery of the function of the heart. Dietary supplementation with physiologically relevant levels of copper can reverse pathological cardiac hypertrophy in mice. Angiogenesis is essential and vascular endothelial growth factor (VEGF) is a constitutive factor for the regression. The action of VEGF is mediated by VEGF receptor-1, whose activation is linked to cyclic GMP-dependent protein kinase-1 (PKG-1) signaling pathways, and inhibition of cyclic GMP degradation leads to regression of pathological cardiac hypertrophy. Most of these pathways are regulated by hypoxia-inducible factor. Potential therapeutic targets for promoting the regression include: promotion of angiogenesis, selective enhancement of VEGF receptor-1 signaling pathways, stimulation of PKG-1 pathways, and sustention of hypoxia-inducible factor transcriptional activity. More exciting insights into the regression of pathological cardiac hypertrophy are emerging. The time of translating the concept of regression of pathological cardiac hypertrophy to clinical practice is coming. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Cardiac evaluation in children with Prader-Willi syndrome.

    NARCIS (Netherlands)

    Marcus, K.A.; Alfen-van der Velden, J. van; Otten, B.J.; Weijers, G.; Yntema, H.G.; Korte, C.L. de; Kapusta, L.

    2012-01-01

    AIM: To assess cardiac anatomy and myocardial systolic function in children with Prader-Willi syndrome (PWS). METHODS: Physical examination, electrocardiographic (ECG) recordings and transthoracic echocardiograms including two-dimensional speckle tracking echocardiography (2DSTE) were performed and

  2. Exercise-based cardiac rehabilitation in patients with heart failure

    DEFF Research Database (Denmark)

    Lewinter, Christian; Doherty, Patrick; Gale, Christopher P

    2015-01-01

    BACKGROUND: Guidelines recommend exercise-based cardiac rehabilitation (EBCR) for patients with heart failure (HF). However, established research has not investigated the longer-term outcomes including mortality and hospitalisation in light of the contemporary management of HF. METHODS...

  3. Optical modulator including grapene

    Science.gov (United States)

    Liu, Ming; Yin, Xiaobo; Zhang, Xiang

    2016-06-07

    The present invention provides for a one or more layer graphene optical modulator. In a first exemplary embodiment the optical modulator includes an optical waveguide, a nanoscale oxide spacer adjacent to a working region of the waveguide, and a monolayer graphene sheet adjacent to the spacer. In a second exemplary embodiment, the optical modulator includes at least one pair of active media, where the pair includes an oxide spacer, a first monolayer graphene sheet adjacent to a first side of the spacer, and a second monolayer graphene sheet adjacent to a second side of the spacer, and at least one optical waveguide adjacent to the pair.

  4. Changes in left ventricular systolic and diastolic function on serial echocardiography after out-of-hospital cardiac arrest.

    Science.gov (United States)

    Jentzer, Jacob C; Anavekar, Nandan S; Mankad, Sunil V; White, Roger D; Kashani, Kianoush B; Barsness, Gregory W; Rabinstein, Alejandro A; Pislaru, Sorin V

    2018-02-10

    Reversible myocardial dysfunction is common after out-of-hospital cardiac arrest (OHCA). The aim of this study was to determine if changes on serial transthoracic echocardiography (TTE) can predict long-term mortality in OHCA subjects. This is a single-center historical cohort study of OHCA subjects undergoing targeted temperature management who received >1 TTE during hospitalization. Two-dimensional and Doppler parameters of systolic and diastolic function were compared between paired TTE. Univariate analysis was used to determine associations between TTE parameters and all-cause mortality. Fifty-nine patients were included; mean age was 59.4 ± 11.2 years (75% male). Initial rhythm was shockable in 90%. Initial TTE was done a median of 10.4 h after admission and repeat TTE was done 5.7 ± 4.1 days later. Between TTE studies, there were significant increases in left ventricular ejection fraction (LVEF, from 32% to 43%), cardiac output, stroke volume, and other Doppler-derived hemodynamic parameters, while systemic vascular resistance decreased (all p TTE were not associated with follow-up mortality. Patients who died during follow-up (n = 16, 27%) had smaller increases in LVEF and cardiac output-derived hemodynamic parameters than long-term survivors (p TTE after OHCA, consistent with reversible post-arrest myocardial dysfunction. The magnitude of those changes is greater in long-term survivors, emphasizing that the degree of recovery from post-arrest myocardial dysfunction may be more important than its initial severity. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Prototype development of an electrical impedance based simultaneous respiratory and cardiac monitoring system for gated radiotherapy.

    Science.gov (United States)

    Kohli, Kirpal; Liu, Jeff; Schellenberg, Devin; Karvat, Anand; Parameswaran, Ash; Grewal, Parvind; Thomas, Steven

    2014-10-14

    In radiotherapy, temporary translocations of the internal organs and tumor induced by respiratory and cardiac activities can undesirably lead to significantly lower radiation dose on the targeted tumor but more harmful radiation on surrounding healthy tissues. Respiratory and cardiac gated radiotherapy offers a potential solution for the treatment of tumors located in the upper thorax. The present study focuses on the design and development of simultaneous acquisition of respiratory and cardiac signal using electrical impedance technology for use in dual gated radiotherapy. An electronic circuitry was developed for monitoring the bio-impedance change due to respiratory and cardiac motions and extracting the cardiogenic ECG signal. The system was analyzed in terms of reliability of signal acquisition, time delay, and functionality in a high energy radiation environment. The resulting signal of the system developed was also compared with the output of the commercially available Real-time Position Management™ (RPM) system in both time and frequency domains. The results demonstrate that the bioimpedance-based method can potentially provide reliable tracking of respiratory and cardiac motion in humans, alternative to currently available methods. When compared with the RPM system, the impedance-based system developed in the present study shows similar output pattern but different sensitivities in monitoring different respiratory rates. The tracking of cardiac motion was more susceptible to interference from other sources than respiratory motion but also provided synchronous output compared with the ECG signal extracted. The proposed hardware-based implementation was observed to have a worst-case time delay of approximately 33 ms for respiratory monitoring and 45 ms for cardiac monitoring. No significant effect on the functionality of the system was observed when it was tested in a radiation environment with the electrode lead wires directly exposed to high-energy X

  6. Fetal cardiac assessment

    International Nuclear Information System (INIS)

    Greene, K.R.

    1983-01-01

    The better understanding of fetal cardiovascular physiology coupled with improved technology for non-invasive study of the fetus now enable much more detailed assessment of fetal cardiac status than by heart rate alone. Even the latter, relatively simple, measurement contains much more information than was previously realized. It is also increasingly clear that no single measurement will provide the answer to all clinical dilemmas either on cardiac function or the welfare of the fetus as a whole. There are obvious clinical advantages in measuring several variables from one signal and the measurement of heart rate, heart rate variation and waveform from the ECG in labour is a potentially useful combination. Systolic time intervals or flow measurements could easily be added or used separately by combining real-time and Doppler ultrasound probes

  7. Cardiac nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Gerson, M.C.

    1987-01-01

    The book begins with a review of the radionuclide methods available for evaluating cardiac perfusion and function. The authors discuss planar and tomographic thallium myocardial imaging, first-pass and equilibrium radionuclide angiography, and imaging with infarct-avid tracers. Several common but more specialized procedures are then reviewed: nonogemetric measurement of left ventricular volume, phase (Fourier) analysis, stroke volume ratio, right ventricular function, and diastolic function. A separate chapter is devoted to drug interventions and in particular the use of radionuclide ventriculography to monitor doxorubicin toxicity and therapy of congestive heart failure. The subsequent chapters provide a comprehensive guide to test selection, accuracy, and results in acute myocardial infarction, in postmyocardial infarction, in chronic coronary artery disease, before and after medical or surgical revascularization, in valvular heart disease, in cardiomyopathies, and in cardiac trauma.

  8. Use of Follicular Output Rate to Predict Intracytoplasmic Sperm Injection Outcome

    Directory of Open Access Journals (Sweden)

    Rehman Rehana

    2016-07-01

    Full Text Available Background The measurement of follicular output rate (FORT has been proposed as a good indicator for evaluating follicular response to the exogenous recombinant folliclestimulating hormone (rFSH. This places FORT as a promising qualitative marker for ovarian function. The objective of the study was to determine FORT as a predictor of oocyte competence, embryo quality and clinical pregnancy after intracytoplasmic sperm injection (ICSI. Materials and Methods This prospective study was carried out on a group of infer- tile females (n=282 at Islamabad Clinic Serving Infertile Couples, Islamabad, Pakistan, from June 2010 till August 2013. Downregulated females were stimulated in injection gonadotropins and on ovulation induction day, pre-ovulatory follicle count (PFC was determined using transvaginal ultrasound scan (TVUS, and FORT was determined as a ratio of PFC to antral follicle count (AFC×100. Group I consisted of females with a negative pregnancy test, while group II had a positive pregnancy test that was confirmed with the appearance of fetal cardiac activity. Linear regression analyses of categorical variables of clinical pregnancy along with other independent variables, including FORT, were performed using SPSS version 15.0. Results Pregnancy occurred in 101/282 women who were tested, recording a clinical pregnancy rate of about 35.8%. FORT values were higher in group II as compared to group I females (P=0.0001. In multiple regression analysis, 97.7, 87.1, 78.2, and 83.4% variations were explained based on the number of retrieved oocytes per patients, number of metaphase II oocytes retrieved, number of fertilized oocytes, and number of cleaved embryos, respectively, indicating FORT as an independent predictor. Conclusion FORT is a predictor of oocyte competence in terms of a number of retrieved, mature and fertilized oocytes. It also gives information about the number of cleaved embryos and clinical pregnancy rate.

  9. Perioperative hyperoxia and post-operative cardiac complications in adults undergoing non-cardiac surgery

    DEFF Research Database (Denmark)

    Petersen, C; Wetterslev, J; Meyhoff, C S

    2018-01-01

    linked to increased long-term mortality, but cardiac complications are sparsely evaluated. The aim of this review is to summarize current evidence to assess the risk and benefits of perioperative hyperoxia on post-operative cardiac complications. METHODS: This systematic review will include meta-analyses...... and Trial Sequential Analyses. We will include randomized clinical trials with patients undergoing non-cardiac surgery if the allocation separates patients into a target of either higher (above 0.60) or lower (below 0.40) inspired oxygen fraction. To minimize the risk of systematic error, we will assess...... that the risk of myocardial injury and infarction is elevated in patients with hyperoxia due to vasoconstriction and formation of reactive oxygen species. Due to lack of symptoms or silent ischaemia, post-operative myocardial injury may be missed clinically. In some studies, perioperative hyperoxia has been...

  10. Computing multiple-output regression quantile regions

    Czech Academy of Sciences Publication Activity Database

    Paindaveine, D.; Šiman, Miroslav

    2012-01-01

    Roč. 56, č. 4 (2012), s. 840-853 ISSN 0167-9473 R&D Projects: GA MŠk(CZ) 1M06047 Institutional research plan: CEZ:AV0Z10750506 Keywords : halfspace depth * multiple -output regression * parametric linear programming * quantile regression Subject RIV: BA - General Mathematics Impact factor: 1.304, year: 2012 http://library.utia.cas.cz/separaty/2012/SI/siman-0376413.pdf

  11. Galois connection for multiple-output operations

    Czech Academy of Sciences Publication Activity Database

    Jeřábek, Emil

    2018-01-01

    Roč. 79 (2018), č. článku 17. ISSN 0002-5240 EU Projects: European Commission(XE) 339691 - FEALORA Institutional support: RVO:67985840 Keywords : clones and coclones * Galois connection * multiple-output operations Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics Impact factor: 0.625, year: 2016 https://link.springer.com/ article /10.1007%2Fs00012-018-0499-7

  12. Galois connection for multiple-output operations

    Czech Academy of Sciences Publication Activity Database

    Jeřábek, Emil

    2018-01-01

    Roč. 79 (2018), č. článku 17. ISSN 0002-5240 EU Projects: European Commission(XE) 339691 - FEALORA Institutional support: RVO:67985840 Keywords : clones and coclones * Galois connection * multiple-output operations Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics Impact factor: 0.625, year: 2016 https://link.springer.com/article/10.1007%2Fs00012-018-0499-7

  13. Increasing Efficiency by Maximizing Electrical Output

    Science.gov (United States)

    2016-07-27

    turbines whose efficiency decreases with system size driving up costs . The cost in $/W for our system is substantially less than other competitive...basis. That forecast of a $100,000 sales price is based on a detailed analysis of anticipated bill of materials costs when manufacturing and...27-07-2016 Cost and Performance Report 04/01/2012 - 07/01/2016 Increasing Efficiency by Maximizing Electrical Output Ted Eveleth, COO, Ener-G-Rotors

  14. Topical minoxidil: cardiac effects in bald man.

    Science.gov (United States)

    Leenen, F H; Smith, D L; Unger, W P

    1988-01-01

    Systemic cardiovascular effects during chronic treatment with topical minoxidil vs placebo were evaluated using a double-blind, randomized design for two parallel groups (n = 20 for minoxidil, n = 15 for placebo). During 6 months of follow-up, blood pressure did not change, whereas minoxidil increased heart rate by 3-5 beats min-1. Compared with placebo, topical minoxidil caused significant increases in LV end-diastolic volume, in cardiac output (by 0.751 min-1) and in LV mass (by 5 g m-2). We conclude that in healthy subjects short-term use of topical minoxidil is likely not to be detrimental. However, safety needs to be established regarding ischaemic symptoms in patients with coronary artery disease as well as for the possible development of LV hypertrophy in healthy subjects during years of therapy. PMID:3191000

  15. A Statistical Representation of Pyrotechnic Igniter Output

    Science.gov (United States)

    Guo, Shuyue; Cooper, Marcia

    2017-06-01

    The output of simplified pyrotechnic igniters for research investigations is statistically characterized by monitoring the post-ignition external flow field with Schlieren imaging. Unique to this work is a detailed quantification of all measurable manufacturing parameters (e.g., bridgewire length, charge cavity dimensions, powder bed density) and associated shock-motion variability in the tested igniters. To demonstrate experimental precision of the recorded Schlieren images and developed image processing methodologies, commercial exploding bridgewires using wires of different parameters were tested. Finally, a statistically-significant population of manufactured igniters were tested within the Schlieren arrangement resulting in a characterization of the nominal output. Comparisons between the variances measured throughout the manufacturing processes and the calculated output variance provide insight into the critical device phenomena that dominate performance. Sandia National Laboratories is a multi-mission laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's NNSA under contract DE-AC04-94AL85000.

  16. The output mode cleaner of GEO 600

    International Nuclear Information System (INIS)

    Prijatelj, M; Grote, H; Leong, J; Affeldt, C; Lück, H; Slutsky, J; Wittel, H; Strain, K; Danzmann, K; Degallaix, J; Hild, S

    2012-01-01

    The German-British interferometric gravitational wave detector GEO 600 is currently undergoing upgrades within the GEO-HF upgrade program. The goal of this program is to enhance the sensitivity of GEO 600, in particular at frequencies above 500 Hz. At these frequencies, the detector is limited by shot noise. An important element of the upgrade is the implementation of an output mode cleaner (OMC). This filtering cavity suppresses higher order spatial and temporal modes in the interferometer's output beam, thereby reducing the shot noise and enhancing sensitivity. Fully automated lock acquisition for the OMC was developed in order to ensure a high duty cycle of GEO 600. To maintain optimum sensitivity, the resonance condition of the OMC must be matched to the output beam from the interferometer. This requires continuous control of the resonance frequency of the OMC to the light, and alignment of the beam to the OMC. We describe the design and implementation of the OMC with special attention to the control techniques employed. We present results from the experience gained during the S6/VSR3 science run. Furthermore, we describe an upper limit measurement of the internal displacement noise of a piezoelectric actuator. (paper)

  17. Solar Power Station Output Inverter Control Design

    Directory of Open Access Journals (Sweden)

    J. Bauer

    2011-04-01

    Full Text Available The photovoltaic applications spreads in these days fast, therefore they also undergo great development. Because the amount of the energy obtained from the panel depends on the surrounding conditions, as intensity of the sun exposure or the temperature of the solar array, the converter must be connected to the panel output. The Solar system equipped with inverter can supply small loads like notebooks, mobile chargers etc. in the places where the supplying network is not present. Or the system can be used as a generator and it shall deliver energy to the supply network. Each type of the application has different requirements on the converter and its control algorithm. But for all of them the one thing is common – the maximal efficiency. The paper focuses on design and simulation of the low power inverter that acts as output part of the whole converter. In the paper the design of the control algorithm of the inverter for both types of inverter application – for islanding mode and for operation on the supply grid – is discussed. Attention is also paid to the design of the output filter that should reduce negative side effects of the converter on the supply network.

  18. Characterizing detonator output using dynamic witness plates

    International Nuclear Information System (INIS)

    Murphy, Michael John; Adrian, Ronald J.

    2009-01-01

    A sub-microsecond, time-resolved micro-particle-image velocimetry (PIV) system is developed to investigate the output of explosive detonators. Detonator output is directed into a transparent solid that serves as a dynamic witness plate and instantaneous shock and material velocities are measured in a two-dimensional plane cutting through the shock wave as it propagates through the solid. For the case of unloaded initiators (e.g. exploding bridge wires, exploding foil initiators, etc.) the witness plate serves as a surrogate for the explosive material that would normally be detonated. The velocity-field measurements quantify the velocity of the shocked material and visualize the geometry of the shocked region. Furthermore, the time-evolution of the velocity-field can be measured at intervals as small as 10 ns using the PIV system. Current experimental results of unloaded exploding bridge wire output in polydimethylsiloxane (PDMS) witness plates demonstrate 20 MHz velocity-field sampling just 300 ns after initiation of the wire.

  19. Avaliação da correlação entre o dióxido de carbono expirado e o débito cardíaco em pacientes submetidos à cirurgia cardíaca com circulação extracorpórea Evaluación de la correlación entre el dióxido de carbono expirado y el débito cardíaco en pacientes sometidos a la cirugía cardíaca con circulación extracorpórea Correlation between end-tidal carbon dioxide levels and cardiac output during cardiac surgery with cardiopulmonary bypass

    Directory of Open Access Journals (Sweden)

    Karina Takesaki Miyaji

    2004-10-01

    reflects pulmonary blood perfusion, thus cardiac output (CO. This study aimed at evaluating the correlation between P ET CO2 levels and CO during cardiac surgery with cardiopulmonary bypass (CPB. METHODS: Participated in this study 25 patients submitted to coronary artery bypass grafting (CABG with CPB. End-tidal CO2 monitoring started after tracheal intubation. Cardiac output was determined by thermodilution with pulmonary artery catheter (Swan-Ganz. Carbon dioxide partial blood pressure (PaCO2 was obtained with arterial blood gases analysis. Studied parameters were evaluated in the following moments: immediately after general anesthesia induction, before cardiopulmonary bypass, at cardiopulmonary bypass completion and at surgery completion. RESULTS: Statistical analysis has not shown correlation between P ET CO2 and CO2, or between P ET CO2-PaCO2 gradient (Ga-eCO2 and CO. There has been correlation between P ET CO2, Ga-eCO2 and CO values variation as compared to baseline values before CPB, with loss of correlation after CPB until surgery completion. CONCLUSIONS: In this study, where patients submitted to cardiac surgery with CPB were evaluated, ventilation/perfusion changes throughout the procedure might have been the factors determining decreased correlation between cardiac output and end tidal CO2.

  20. Late Ratchet syndrome involving isolated left ventricular lead dislodgement post-cardiac resynchronization therapy defibrillator generator change.

    Science.gov (United States)

    Tan, Vern Hsen; Wong, Kelvin

    2018-04-01

    Lead dislodgement following cardiac implantable electronic device (CIED) generator change is rare. We report a case including the postulate mechanism of an isolated left ventricular lead dislodgement 3 months after cardiac resynchronization therapy defibrillator pulse generator change.

  1. Extreme inputs/outputs for multiple input multiple output linear systems.

    Energy Technology Data Exchange (ETDEWEB)

    Smallwood, David Ora

    2005-09-01

    A linear structure is excited at multiple points with a stationary normal random process. The response of the structure is measured at multiple outputs. If the auto spectral densities of the inputs are specified, the phase relationships between the inputs are derived that will minimize or maximize the trace of the auto spectral density matrix of the outputs. If the autospectral densities of the outputs are specified, the phase relationships between the outputs that will minimize or maximize the trace of the input auto spectral density matrix are derived. It is shown that other phase relationships and ordinary coherence less than one will result in a trace intermediate between these extremes. Least favorable response and some classes of critical response are special cases of the development. It is shown that the derivation for stationary random waveforms can also be applied to nonstationary random, transients, and deterministic waveforms.

  2. Stress-Dose Corticosteroid Versus Placebo in Neonatal Cardiac Operations: A Randomized Controlled Trial.

    Science.gov (United States)

    Suominen, Pertti K; Keski-Nisula, Juho; Ojala, Tiina; Rautiainen, Paula; Jahnukainen, Timo; Hästbacka, Johanna; Neuvonen, Pertti J; Pitkänen, Olli; Niemelä, Jussi; Kaskinen, Anu; Salminen, Jukka; Lapatto, Risto

    2017-10-01

    Corticosteroids can improve the hemodynamic status of neonates with postoperative low cardiac output syndrome after cardiac operations. This study compared a prophylactically administered stress-dose corticosteroid (SDC) regimen against placebo on inflammation, adrenocortical function, and hemodynamic outcome. Forty neonates undergoing elective open heart operations were randomized into two groups. The SDC group received perioperatively 2 mg/kg methylprednisolone, and 6 hours after the operation, a hydrocortisone infusion (0.2 mg/kg/h) was started with tapering doses for 5 days. Placebo was administered in a similar fashion. An adrenocorticotropic hormone stimulation test was performed after the therapy. The primary endpoint of the study was plasma concentration of interleukin (IL-6). Secondary clinical outcomes included plasma cortisol, IL-10, C-reactive protein, echocardiographic systemic ventricle contractility evaluated by the Velocity Vector Imaging program, the inotropic score, and time of delayed sternal closure. The IL-6 values of the SDC group were significantly lower postoperatively than in the placebo group. Significantly lower inotropic scores (p SDC group. The SDC therapy did not suppress the hypothalamic-pituitary-adrenal axis more than placebo. The mean plasma cortisol level did not decline in the placebo group after the operation. The SDC regimen for 5 days postoperatively in neonates was safe and did not cause suppression of the hypothalamic-pituitary-adrenal axis. Furthermore, the open heart operation per se did not lead to adrenal insufficiency in neonates. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  3. Jet and ultrasonic nebuliser output: use of a new method for direct measurement of aerosol output.

    OpenAIRE

    Dennis, J H; Stenton, S C; Beach, J R; Avery, A J; Walters, E H; Hendrick, D J

    1990-01-01

    Output from jet nebulisers is calibrated traditionally by weighing them before and after nebulisation, but the assumption that the weight difference is a close measure of aerosol generation could be invalidated by the concomitant process of evaporation. A method has been developed for measuring aerosol output directly by using a solute (fluoride) tracer and aerosol impaction, and this has been compared with the traditional weight loss method for two Wright, six Turbo, and four Micro-Cirrus je...

  4. A Monte Carlo Study on Multiple Output Stochastic Frontiers

    DEFF Research Database (Denmark)

    Henningsen, Géraldine; Henningsen, Arne; Jensen, Uwe

    In the estimation of multiple output technologies in a primal approach, the main question is how to handle the multiple outputs. Often an output distance function is used, where the classical approach is to exploit its homogeneity property by selecting one output quantity as the dependent variable...

  5. Validation of a definition of excessive postoperative bleeding in infants undergoing cardiac surgery with cardiopulmonary bypass.

    Science.gov (United States)

    Bercovitz, Rachel S; Shewmake, Allison C; Newman, Debra K; Niebler, Robert A; Scott, John P; Stuth, Eckehard; Simpson, Pippa M; Yan, Ke; Woods, Ronald K

    2018-05-01

    To derive and validate an objective definition of postoperative bleeding in neonates and infants undergoing cardiac surgery with cardiopulmonary bypass. Using a retrospective cohort of 124 infants and neonates, we included published bleeding definitions and cumulative chest tube output over different postoperative periods (eg, 2, 12, or 24 hours after intensive care unit admission) in a classification and regression tree model to determine chest tube output volumes that were associated with red blood cell transfusions and surgical re-exploration for bleeding in the first 24 hours after intensive care unit admission. After the definition of excessive bleeding was determined, it was validated via a prospective cohort of 77 infants and neonates. Excessive bleeding was defined as ≥7 mL/kg/h for ≥2 consecutive hours in the first 12 postoperative hours and/or ≥84 mL/kg total for the first 24 postoperative hours and/or surgical re-exploration for bleeding or cardiac tamponade physiology in the first 24 postoperative hours. Excessive bleeding was associated with longer length of hospital stay, increased 30-day readmission rate, and increased transfusions in the postoperative period. The proposed standard definition of excessive bleeding is based on readily obtained objective data and relates to important early clinical outcomes. Application and validation by other institutions will help determine the extent to which our specialty should consider this definition for both clinical investigation and quality improvement initiatives. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  6. Sudden Cardiac Arrest during Participation in Competitive Sports.

    Science.gov (United States)

    Landry, Cameron H; Allan, Katherine S; Connelly, Kim A; Cunningham, Kris; Morrison, Laurie J; Dorian, Paul

    2017-11-16

    The incidence of sudden cardiac arrest during participation in sports activities remains unknown. Preparticipation screening programs aimed at preventing sudden cardiac arrest during sports activities are thought to be able to identify at-risk athletes; however, the efficacy of these programs remains controversial. We sought to identify all sudden cardiac arrests that occurred during participation in sports activities within a specific region of Canada and to determine their causes. In this retrospective study, we used the Rescu Epistry cardiac arrest database (which contains records of every cardiac arrest attended by paramedics in the network region) to identify all out-of-hospital cardiac arrests that occurred from 2009 through 2014 in persons 12 to 45 years of age during participation in a sport. Cases were adjudicated as sudden cardiac arrest (i.e., having a cardiac cause) or as an event resulting from a noncardiac cause, on the basis of records from multiple sources, including ambulance call reports, autopsy reports, in-hospital data, and records of direct interviews with patients or family members. Over the course of 18.5 million person-years of observation, 74 sudden cardiac arrests occurred during participation in a sport; of these, 16 occurred during competitive sports and 58 occurred during noncompetitive sports. The incidence of sudden cardiac arrest during competitive sports was 0.76 cases per 100,000 athlete-years, with 43.8% of the athletes surviving until they were discharged from the hospital. Among the competitive athletes, two deaths were attributed to hypertrophic cardiomyopathy and none to arrhythmogenic right ventricular cardiomyopathy. Three cases of sudden cardiac arrest that occurred during participation in competitive sports were determined to have been potentially identifiable if the athletes had undergone preparticipation screening. In our study involving persons who had out-of-hospital cardiac arrest, the incidence of sudden cardiac

  7. Use of the cardiopulmonary flow index to evaluate cardiac function in thoroughbred horses

    International Nuclear Information System (INIS)

    Guthrie, A.J.; Killeen, V.M.; Grosskopf, J.F.W.

    1991-01-01

    The ratio of the cardiopulmonary blood volume to stroke volume is called the cardiopulmonary flow index (CPFI). The CPFI can be determined indirectly from the simultaneous recording of a radiocardiogram and an electrocardiogram. The CPFI and cardiac output were measured simultaneously in horses that were diagnosed as having cardiac disease. The results obtained from these subjects were compared with those from control animals and significant differences were found between the mean CPFI of the control horses and those with macroscopically visible myocardial fibrosis on post mortem examination. No significant differences were found between the means of the cardiac output measured in either of the groups of horses. The effect of pharmacological acceleration of the heart rate on the CPFI was also studied. Significant differences were found between the mean CPFI and the slopes of the regression lines of CPFI on heart rate of the control and principal groups of horses. These differences were greatest at heart rates near to the resting heart rates of the individuals. The CPFI was found to be a more sensitive measure of cardiac function than cardiac output, in the horses. 16 refs., 2 figs., 2 tabs

  8. Predicting Output Power for Nearshore Wave Energy Harvesting

    Directory of Open Access Journals (Sweden)

    Henock Mamo Deberneh

    2018-04-01

    Full Text Available Energy harvested from a Wave Energy Converter (WEC varies greatly with the location of its installation. Determining an optimal location that can result in maximum output power is therefore critical. In this paper, we present a novel approach to predicting the output power of a nearshore WEC by characterizing ocean waves using floating buoys. We monitored the movement of the buoys using an Arduino-based data collection module, including a gyro-accelerometer sensor and a wireless transceiver. The collected data were utilized to train and test prediction models. The models were developed using machine learning algorithms: SVM, RF and ANN. The results of the experiments showed that measurements from the data collection module can yield a reliable predictor of output power. Furthermore, we found that the predictors work better when the regressors are combined with a classifier. The accuracy of the proposed prediction model suggests that it could be extremely useful in both locating optimal placement for wave energy harvesting plants and designing the shape of the buoys used by them.

  9. Correlation between renew able energy source's energy output and load

    International Nuclear Information System (INIS)

    Ali, G.H.M.; El-Zeftawy, A.A.

    1996-01-01

    The common problem to all renew energy sources (RESs) is the mismatch between their energy output and load demand. In remote areas, the solution of this problem is in general employing a small diesel-generator or a storage battery. But, the storage battery is a major cost element of RESs and small diesel-generator is unreliable and costly. Therefore, a proposed technique has been introduced in this work to determine correlation between the energy output of wind energy systems (WES) and isolated loads. solar photovoltaic power system (PVS) and two of energy storage facilities are used here for this correlation. The proposed technique includes also two models for optimizing the generation and costs of WES accompanied with PVS, storage battery and water storage (reservoir) to accommodate an isolated load. The proposed technique is applied with the dynamic programming to coordinate the energy output of a WES with residential and pumping load in remote area of egypt. The results of this application reveal that minimization of both capacity of the storage battery and the whole power system cost are obtained. 4 figs

  10. Echocardiographic evaluation of cardiac resynchronization therapy

    Directory of Open Access Journals (Sweden)

    Petrović Milan

    2006-01-01

    Full Text Available Introduction: Cardiac resynchronization therapy (CRT is relatively new tool in treatment of chronic heart failure (HF, especially in dilated cardiomyopathy (DCM with the left bundle branch block (LBBB. Objective: The Objective of our study was to assess the success of CRT in treatment of severe HF and the role of echocardiography in the evaluation of Results of such therapy. Method: The group consisted of 19 patients, 13 males and 6 females, mean age 58.0±8.22 years (47-65 years with CRT applied for DCM, severe HF (NYHA III-IV, LBBB and ejection fraction (EF <35%. The mean follow up was 17 months (6.5-30. Standard color Doppler echocardiography examination was performed in all patients before and after CRT. The parameters of systolic and diastolic left ventricular function, mitral insufficiency and the right ventricular pressure were evaluated. Results: Following the CRT, statistically significant improvement of the end-systolic LV dimension, cardiac output, cardiac index, myocardial performance index (p<0.01 and stroke index (p<0.05 was recorded. The mean value of EFLV was increased by 10% and LV fractional shortening improved by 6% in 10/16 (62% patients. CRT resulted in decreased MR (p<0.01, prolonged LV diastolic filling time (p<0.02 and reduced RV pressure (p<0.05. Interventricular mechanical delay was shortened by 28% (18 msec Conclusion: CRT has an important role in improvement of LV function and correction of ventricular asynchrony. The echocardiography is a useful tool for evaluation of HF treatment with CRT.

  11. Silicon central pattern generators for cardiac diseases.

    Science.gov (United States)

    Nogaret, Alain; O'Callaghan, Erin L; Lataro, Renata M; Salgado, Helio C; Meliza, C Daniel; Duncan, Edward; Abarbanel, Henry D I; Paton, Julian F R

    2015-02-15

    Cardiac rhythm management devices provide therapies for both arrhythmias and resynchronisation but not heart failure, which affects millions of patients worldwide. This paper reviews recent advances in biophysics and mathematical engineering that provide a novel technological platform for addressing heart disease and enabling beat-to-beat adaptation of cardiac pacing in response to physiological feedback. The technology consists of silicon hardware central pattern generators (hCPGs) that may be trained to emulate accurately the dynamical response of biological central pattern generators (bCPGs). We discuss the limitations of present CPGs and appraise the advantages of analog over digital circuits for application in bioelectronic medicine. To test the system, we have focused on the cardio-respiratory oscillators in the medulla oblongata that modulate heart rate in phase with respiration to induce respiratory sinus arrhythmia (RSA). We describe here a novel, scalable hCPG comprising physiologically realistic (Hodgkin-Huxley type) neurones and synapses. Our hCPG comprises two neurones that antagonise each other to provide rhythmic motor drive to the vagus nerve to slow the heart. We show how recent advances in modelling allow the motor output to adapt to physiological feedback such as respiration. In rats, we report on the restoration of RSA using an hCPG that receives diaphragmatic electromyography input and use it to stimulate the vagus nerve at specific time points of the respiratory cycle to slow the heart rate. We have validated the adaptation of stimulation to alterations in respiratory rate. We demonstrate that the hCPG is tuneable in terms of the depth and timing of the RSA relative to respiratory phase. These pioneering studies will now permit an analysis of the physiological role of RSA as well as its any potential therapeutic use in cardiac disease. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.

  12. [Hydatidosis simulating a cardiac tumour with pulmonary metastases].

    Science.gov (United States)

    Martín-Izquierdo, Marta; Martín-Trenor, Alejandro

    2016-01-01

    The presence of multiple symptomatic pulmonary nodules and one cardiac tumour in a child requires urgent diagnosis and treatment. Until a few decades ago, the diagnosis of a cardiac tumour was difficult and was based on a high index of suspicion from indirect signs, and required angiocardiography for confirmation. Echocardiography and other imaging techniques have also helped in the detection of cardiac neoplasms. However, it is not always easy to make the correct diagnosis. The case is presented of a 12 year-old boy with pulmonary symptoms, and diagnosed with a cardiac tumour with lung metastases. The presence of numerous pulmonary nodules was confirmed in our hospital. The echocardiogram detected a solid cardiac nodule in the right ventricle. Magnetic resonance imaging confirmed the findings and the diagnosis. Puncture-aspiration of a lung nodule gave the diagnosis of hydatidosis. He underwent open-heart surgery with cardiac cyst resection and treated with anthelmintics. The lung cysts were then excised, and he recovered uneventfully. This child had multiple pulmonary nodules and a solid cardiac nodule, and was suspected of having a cardiac tumour with pulmonary metastases. However, given the clinical history, background and morphology of pulmonary nodules, another possible aetiology for consideration is echinococcosis. The clinical picture of cardiac hydatidosis and its complications is highly variable. The clinical history is essential in these cases, as well as having a high index of suspicion. Hydatidosis should be included in the differential diagnosis of a solid, echogenic, cardiac nodule. The treatment for cardiopulmonary hydatid cysts is surgical, followed by anthelmintics. Copyright © 2015 Academia Mexicana de Cirugía A.C. Published by Masson Doyma México S.A. All rights reserved.

  13. Frequency of Cardiac Arrhythmias in Patients with Aluminum Phosphide Poisoning

    Directory of Open Access Journals (Sweden)

    Umair Aziz

    2015-12-01

    Full Text Available Background: Cardiac failure is the major lethal consequence of aluminum phosphide (AlP poisoning. This study was designed to determine the frequency of cardiac arrhythmias in patients with AlP poisoning. Methods: In this prospective cross-sectional study, patients with definitive history of AlP poisoning treated at emergency department of Allied Hospital Faisalabad, Faisalabad, Pakistan, from July 2013 to November 2014 were included. On admission, twelve-lead electrocardiogram (ECG was performed for all patients. During admission, all patients underwent continuous cardiac monitoring using a cardiac monitor. If an arrhythmia was suspected on the cardiac monitor, another ECG was obtained immediately.  Results: During the study period, 100 patients with AlP poisoning (63% men were treated at Allied Hospital Faisalabad. Mean age of the patients was 26.7 ± 7.9 years ranging from 16 to 54 years. Tachycardia was detected in 68 patients and bradycardia in 12 patients. Hypotension was observed in 75 patients. Eighty patients developed cardiac arrhythmia. The most frequent arrhythmia was atrial fibrillation (31% of patients followed by ventricular fibrillation (20%, ventricular tachycardia (17%, 3rd degree AV block (7% and 2nd degree AV block (5%. In total, 78 patients died, depicting a 78% mortality rate following wheat pill poisoning. Among those who died, seventy-one patients had cardiac arrhythmia. Comparison of death rate between patients with and without cardiac arrhythmia showed a significant difference (71/80 (88.8% vs. 7/20 (35%; P < 0.001.  Conclusion: Wheat pill poisoning causes a very high mortality, and circulatory collapse is the major cause of death among these patients. Most of the patients with AlP poisoning develop cardiac arrhythmias which are invariably life threatening. Early detection of cardiac disorders and proper management of arrhythmias may reduce mortalities.

  14. Programmed evolution for optimization of orthogonal metabolic output in bacteria.

    Directory of Open Access Journals (Sweden)

    Todd T Eckdahl

    Full Text Available Current use of microbes for metabolic engineering suffers from loss of metabolic output due to natural selection. Rather than combat the evolution of bacterial populations, we chose to embrace what makes biological engineering unique among engineering fields - evolving materials. We harnessed bacteria to compute solutions to the biological problem of metabolic pathway optimization. Our approach is called Programmed Evolution to capture two concepts. First, a population of cells is programmed with DNA code to enable it to compute solutions to a chosen optimization problem. As analog computers, bacteria process known and unknown inputs and direct the output of their biochemical hardware. Second, the system employs the evolution of bacteria toward an optimal metabolic solution by imposing fitness defined by metabolic output. The current study is a proof-of-concept for Programmed Evolution applied to the optimization of a metabolic pathway for the conversion of caffeine to theophylline in E. coli. Introduced genotype variations included strength of the promoter and ribosome binding site, plasmid copy number, and chaperone proteins. We constructed 24 strains using all combinations of the genetic variables. We used a theophylline riboswitch and a tetracycline resistance gene to link theophylline production to fitness. After subjecting the mixed population to selection, we measured a change in the distribution of genotypes in the population and an increased conversion of caffeine to theophylline among the most fit strains, demonstrating Programmed Evolution. Programmed Evolution inverts the standard paradigm in metabolic engineering by harnessing evolution instead of fighting it. Our modular system enables researchers to program bacteria and use evolution to determine the combination of genetic control elements that optimizes catabolic or anabolic output and to maintain it in a population of cells. Programmed Evolution could be used for applications in

  15. Characterizing the output settings of dental curing lights.

    Science.gov (United States)

    Harlow, J E; Sullivan, B; Shortall, A C; Labrie, D; Price, R B

    2016-01-01

    For improved inter-study reproducibility and ultimately improved patient care, researchers and dentists need to know what electromagnetic radiation (light) is emitted from the light-curing unit (LCU) they are using and what is received by the resin. This information cannot be obtained from a dental radiometer, even though many studies have used a dental radiometer. The light outputs from six LCUs (two QTH and four broad-spectrum LED units) were collected in real-time using an integrating sphere connected to a fiberoptic spectrometer during different light exposures. It was found that the spectral emissions were unique to each LCU, and there was no standardization in what was emitted on the various ramp (soft-start) settings. Relative to the normal use setting, using the ramp setting reduced the radiant energy (J) delivered from each LCU. For one of the four broad-spectrum LED LCUs, the spectral emissions in the violet range did not increase when the overall radiant power output was increased. In addition, this broad-spectrum LED LCU emitted no light from the violet LED chip for the first 5s and only emitted violet light when the ramp phase finished. A single irradiance value derived from a dental radiometer or from a laboratory grade power meter cannot adequately describe the output from the LCU. Manufacturers should provide more information about the light output from their LCUs. Ideally, future assessments and research publications that include resin photopolymerization should report the spectral radiant power delivered from the LCU throughout the entire exposure cycle. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Programmed evolution for optimization of orthogonal metabolic output in bacteria.

    Science.gov (United States)

    Eckdahl, Todd T; Campbell, A Malcolm; Heyer, Laurie J; Poet, Jeffrey L; Blauch, David N; Snyder, Nicole L; Atchley, Dustin T; Baker, Erich J; Brown, Micah; Brunner, Elizabeth C; Callen, Sean A; Campbell, Jesse S; Carr, Caleb J; Carr, David R; Chadinha, Spencer A; Chester, Grace I; Chester, Josh; Clarkson, Ben R; Cochran, Kelly E; Doherty, Shannon E; Doyle, Catherine; Dwyer, Sarah; Edlin, Linnea M; Evans, Rebecca A; Fluharty, Taylor; Frederick, Janna; Galeota-Sprung, Jonah; Gammon, Betsy L; Grieshaber, Brandon; Gronniger, Jessica; Gutteridge, Katelyn; Henningsen, Joel; Isom, Bradley; Itell, Hannah L; Keffeler, Erica C; Lantz, Andrew J; Lim, Jonathan N; McGuire, Erin P; Moore, Alexander K; Morton, Jerrad; Nakano, Meredith; Pearson, Sara A; Perkins, Virginia; Parrish, Phoebe; Pierson, Claire E; Polpityaarachchige, Sachith; Quaney, Michael J; Slattery, Abagael; Smith, Kathryn E; Spell, Jackson; Spencer, Morgan; Taye, Telavive; Trueblood, Kamay; Vrana, Caroline J; Whitesides, E Tucker

    2015-01-01

    Current use of microbes for metabolic engineering suffers from loss of metabolic output due to natural selection. Rather than combat the evolution of bacterial populations, we chose to embrace what makes biological engineering unique among engineering fields - evolving materials. We harnessed bacteria to compute solutions to the biological problem of metabolic pathway optimization. Our approach is called Programmed Evolution to capture two concepts. First, a population of cells is programmed with DNA code to enable it to compute solutions to a chosen optimization problem. As analog computers, bacteria process known and unknown inputs and direct the output of their biochemical hardware. Second, the system employs the evolution of bacteria toward an optimal metabolic solution by imposing fitness defined by metabolic output. The current study is a proof-of-concept for Programmed Evolution applied to the optimization of a metabolic pathway for the conversion of caffeine to theophylline in E. coli. Introduced genotype variations included strength of the promoter and ribosome binding site, plasmid copy number, and chaperone proteins. We constructed 24 strains using all combinations of the genetic variables. We used a theophylline riboswitch and a tetracycline resistance gene to link theophylline production to fitness. After subjecting the mixed population to selection, we measured a change in the distribution of genotypes in the population and an increased conversion of caffeine to theophylline among the most fit strains, demonstrating Programmed Evolution. Programmed Evolution inverts the standard paradigm in metabolic engineering by harnessing evolution instead of fighting it. Our modular system enables researchers to program bacteria and use evolution to determine the combination of genetic control elements that optimizes catabolic or anabolic output and to maintain it in a population of cells. Programmed Evolution could be used for applications in energy

  17. Modeling and notation of DEA with strong and weak disposable outputs.

    Science.gov (United States)

    Kuntz, Ludwig; Sülz, Sandra

    2011-12-01

    Recent articles published in Health Care Management Science have described DEA applications under the assumption of strong and weak disposable outputs. As we confidently assume that these papers include some methodical deficiencies, we aim to illustrate a revised approach.

  18. Cardiac catheterization laboratory management: the fundamentals.

    Science.gov (United States)

    Newell, Amy

    2012-01-01

    Increasingly, imaging administrators are gaining oversight for the cardiac cath lab as part of imaging services. Significant daily challenges include physician and staff demands, as well as patients who in many cases require higher acuity care. Along with strategic program driven responsibilities, the management role is complex. Critical elements that are the major impacts on cath lab management, as well as the overall success of a cardiac and vascular program, include program quality, patient safety, operational efficiency including inventory management, and customer service. It is critically important to have a well-qualified cath lab manager who acts as a leader by example, a mentor and motivator of the team, and an expert in the organization's processes and procedures. Such qualities will result in a streamlined cath lab with outstanding results.

  19. Descartes, Cardiac Heat, and Alchemy.

    Science.gov (United States)

    Heitsch, Dorothea

    2016-11-01

    René Descartes (1596-1650) insisted on a heat and light theory to explain cardiac movement, and used concepts such as distillation of the vital spirits, fermentation in the digestive process, and fermentation in the circulation of the blood. I argue that his theory of the body as a heat-exchange system was based on alchemical and natural philosophical notions of fire and light expounded by precursors and contemporaries who included Jean D'Espagnet, Jean Fernel, Jan Baptist van Helmont, and Andreas Libavius. Descartes endeavoured to mechanise their approaches, creating a theory in which fire and heat, a legacy from thermal explanations of physiology, were transformed into alchemical fire, and then into mechanistic or physicalist heat.

  20. Fractals analysis of cardiac arrhythmias.

    Science.gov (United States)

    Saeed, Mohammed

    2005-09-06

    Heart rhythms are generated by complex self-regulating systems governed by the laws of chaos. Consequently, heart rhythms have fractal organization, characterized by self-similar dynamics with long-range order operating over multiple time scales. This allows for the self-organization and adaptability of heart rhythms under stress. Breakdown of this fractal organization into excessive order or uncorrelated randomness leads to a less-adaptable system, characteristic of aging and disease. With the tools of nonlinear dynamics, this fractal breakdown can be quantified with potential applications to diagnostic and prognostic clinical assessment. In this paper, I review the methodologies for fractal analysis of cardiac rhythms and the current literature on their applications in the clinical context. A brief overview of the basic mathematics of fractals is also included. Furthermore, I illustrate the usefulness of these powerful tools to clinical medicine by describing a novel noninvasive technique to monitor drug therapy in atrial fibrillation.