[Measurement of cardiac output by thermodilution with a diode as a temperature sensor].

Science.gov (United States)

Díaz Fernández, A; Benítez, D; Sánchez Tello, G; Márquez, L A

1979-01-01

An area integrator for the thermodilution curve in cardiac output measurement is described. A new temperature sensor is used, a diode with some advantages over the thermistor normally used. The main advantages are: easy calibration and replacement, and broad range of linearity. The cardiac output values obtained in dog with the integrator follow a linear relationship with those of the flowmeter. In simultaneous measurements the correlation is R = 0.96. Using a diode as temperature sensor a modification of the Steward Hamilton equation (used for thermistor) is necessary. With this new equation a monogram is performed to calculate the cardiac output from the area given by the numerical integrator.

Fluid challenge: tracking changes in cardiac output with blood pressure monitoring (invasive or non-invasive).

Science.gov (United States)

Lakhal, Karim; Ehrmann, Stephan; Perrotin, Dominique; Wolff, Michel; Boulain, Thierry

2013-11-01

To assess whether invasive and non-invasive blood pressure (BP) monitoring allows the identification of patients who have responded to a fluid challenge, i.e., who have increased their cardiac output (CO). Patients with signs of circulatory failure were prospectively included. Before and after a fluid challenge, CO and the mean of four intra-arterial and oscillometric brachial cuff BP measurements were collected. Fluid responsiveness was defined by an increase in CO ≥10 or ≥15% in case of regular rhythm or arrhythmia, respectively. In 130 patients, the correlation between a fluid-induced increase in pulse pressure (Δ500mlPP) and fluid-induced increase in CO was weak and was similar for invasive and non-invasive measurements of BP: r² = 0.31 and r² = 0.29, respectively (both p area under the receiver-operating curve (AUC) of 0.82 (0.74-0.88), similar (p = 0.80) to that of non-invasive Δ500mlPP [AUC of 0.81 (0.73-0.87)]. Outside large gray zones of inconclusive values (5-23% for invasive Δ500mlPP and 4-35% for non-invasive Δ500mlPP, involving 35 and 48% of patients, respectively), the detection of responsiveness or unresponsiveness to fluid was reliable. Cardiac arrhythmia did not impair the performance of invasive or non-invasive Δ500mlPP. Other BP-derived indices did not outperform Δ500mlPP. As evidenced by large gray zones, BP-derived indices poorly reflected fluid responsiveness. However, in our deeply sedated population, a high increase in invasive pulse pressure (>23%) or even in non-invasive pulse pressure (>35%) reliably detected a response to fluid. In the absence of a marked increase in pulse pressure (<4-5%), a response to fluid was unlikely.

[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

Comparison of dye dilution method to radionuclide techniques for cardiac output determination in dogs

International Nuclear Information System (INIS)

Eng, S.S.; Robayo, J.R.; Porter, W.; Smith, R.E.

1980-01-01

A study was undertaken to identify the most accurate /sup 99m/Tc-labeled radiopharmaceutical and to determine the accuracy of a noninvasive radionuclide technique or cardiac output determinations. Phase I employed sodium pertechnetate, stannous pyrophosphate with sodium pertechnetate, /sup 99m/Tc red blood cells, and /sup 99m/Tc human serum albumin as radionuclide tracers. Cardiac output was determined by the dye dilution method and then by the invasive radionuclide technique. A pairied t test and regression analysis indicated that /sup 99m/Tc human serum albumin was the most accurate radiopharmaceutical for cardiac output determinations, and the results compared favorably to those obtained by the dye dilution method. In Phase II, /sup 99m/Tc human serum albumin was used as the radionuclide tracer for cardiac output determinations with the noninvasive technique. The results compared favorably to those obtained by the dye dilution method

Measurement of cardiac output in man with MR imaging

International Nuclear Information System (INIS)

Lipton, M.J.; Weikl, A.; Mueller, E.; Reinhardt, E.R.

1987-01-01

Multiecho electrocardiogram-triggered imaging sequences were obtained in 15 patients to measure aortic blood flow velocity in a 6-cm thick section. The aortic area was calculated from MR images; cardiac output was calculated as the product of velocity and area and was expressed in liters per minute. MR imaging results were compared with measurements obtained by cardiac catheterization and thermodilution. A good correlation of 0.9 was found, with a slope approaching unity

An update on insertable cardiac monitors

DEFF Research Database (Denmark)

Olsen, Flemming J; Biering-Sørensen, Tor; Krieger, Derk W

2015-01-01

Continuous cardiac rhythm monitoring has undergone compelling progress over the past decades. Cardiac monitoring has emerged from 12-lead electrocardiograms being performed at the discretion of the treating physician to in-hospital telemetry, Holter monitoring, prolonged external event monitoring...... turning point in the field of arrhythmia management. However, their role in the detection of paroxysmal atrial fibrillation after cryptogenic strokes has yet to evolve. This will be the main focus of this review. Issues surrounding patient selection, clinical relevance and determination of cost......-effectiveness for prolonged cardiac monitoring require further studies. Furthermore, insertable cardiac monitoring has not only the potential to augment diagnostic capabilities but also to improve the management of paroxysmal atrial fibrillation....

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......, the estimated pulmonary artery diastolic pressure (ePAD) was analysed. RESULTS: The magnitude of CO response to AVD changes was greater in CRT patients than in controls (0.25 vs. 0.20 L/min, Psize (r=0...

Serum cortisol concentration with exploratory cut-off values do not predict the effects of hydrocortisone administration in children with low cardiac output after cardiac surgery.

Science.gov (United States)

Verweij, E J; Hogenbirk, Karin; Roest, Arno A W; van Brempt, Ronald; Hazekamp, Mark G; de Jonge, Evert

2012-10-01

Low cardiac output syndrome is common after paediatric cardiac surgery. Previous studies suggested that hydrocortisone administration may improve haemodynamic stability in case of resistant low cardiac output syndrome in critically ill children. This study was set up to test the hypothesis that the effects of hydrocortisone on haemodynamics in children with low cardiac output syndrome depend on the presence of (relative) adrenal insufficiency. A retrospective study was done on paediatric patients who received hydrocortisone when diagnosed with resistant low cardiac output syndrome after paediatric cardiac surgery in the period from 1 November 2005 to 31 December 2008. We studied the difference in effects of treatment with hydrocortisone administration between patients with adrenal insufficiency defined as an exploratory cut-off value of total cortisol of cortisol of ≥ 100 nmol/l. A total of 62 of patients were enrolled, meeting the inclusion criteria for low cardiac output syndrome. Thirty-two patients were assigned to Group 1 (cortisol concentration and those with normal baseline cortisol levels. A cortisol value using an exploratory cut-off value of 100 nmol/l for adrenal insufficiency should not be used as a criterion to treat these patients with hydrocortisone.

Serum cortisol concentration with exploratory cut-off values do not predict the effects of hydrocortisone administration in children with low cardiac output after cardiac surgery

NARCIS (Netherlands)

Verweij, E. J.; Hogenbirk, Karin; Roest, Arno A. W.; van Brempt, Ronald; Hazekamp, Mark G.; de Jonge, Evert

2012-01-01

Low cardiac output syndrome is common after paediatric cardiac surgery. Previous studies suggested that hydrocortisone administration may improve haemodynamic stability in case of resistant low cardiac output syndrome in critically ill children. This study was set up to test the hypothesis that the

Validation of an ultrasound dilution technology for cardiac output measurement and shunt detection in infants and children.

Science.gov (United States)

Lindberg, Lars; Johansson, Sune; Perez-de-Sa, Valeria

2014-02-01

To validate cardiac output measurements by ultrasound dilution technology (COstatus monitor) against those obtained by a transit-time ultrasound technology with a perivascular flow probe and to investigate ultrasound dilution ability to estimate pulmonary to systemic blood flow ratio in children. Prospective observational clinical trial. Pediatric cardiac operating theater in a university hospital. In 21 children (6.1 ± 2.6 kg, mean ± SD) undergoing heart surgery, cardiac output was simultaneously recorded by ultrasound dilution (extracorporeal arteriovenous loop connected to existing arterial and central venous catheters) and a transit-time ultrasound probe applied to the ascending aorta, and when possible, the main pulmonary artery. The pulmonary to systemic blood flow ratio estimated from ultrasound dilution curve analysis was compared with that estimated from transit-time ultrasound technology. Bland-Altman analysis of the whole cohort (90 pairs, before and after surgery) showed a bias between transit-time ultrasound (1.01 ± 0.47 L/min) and ultrasound dilution technology (1.03 ± 0.51 L/min) of -0.02 L/min, limits of agreement -0.3 to 0.3 L/min, and percentage error of 31%. In children with no residual shunts, the bias was -0.04 L/min, limits of agreement -0.28 to 0.2 L/min, and percentage error 19%. The pooled co efficient of variation was for the whole cohort 3.5% (transit-time ultrasound) and 6.3% (ultrasound dilution), and in children without shunt, it was 2.9% (transit-time ultrasound) and 4% (ultrasound dilution), respectively. Ultrasound dilution identified the presence of shunts (pulmonary to systemic blood flow ≠ 1) with a sensitivity of 100% and a specificity of 92%. Mean pulmonary to systemic blood flow ratio by transit-time ultrasound was 2.6 ± 1.0 and by ultrasound dilution 2.2 ± 0.7 (not significant). The COstatus monitor is a reliable technique to measure cardiac output in children with high sensitivity and specificity for detecting the

Simultaneous cardiac output and regional myocardial perfusion determination with PET and nitrogen 13 ammonia

DEFF Research Database (Denmark)

Hove, Jens D; Kofoed, Klaus F; Wu, Hsiao M

2003-01-01

The purpose of this study was to evaluate the possibility of measuring cardiac output during positron emission tomography (PET) examination of myocardial perfusion with nitrogen 13 ammonia.......The purpose of this study was to evaluate the possibility of measuring cardiac output during positron emission tomography (PET) examination of myocardial perfusion with nitrogen 13 ammonia....

In Vivo Self-Powered Wireless Cardiac Monitoring via Implantable Triboelectric Nanogenerator.

Science.gov (United States)

Zheng, Qiang; Zhang, Hao; Shi, Bojing; Xue, Xiang; Liu, Zhuo; Jin, Yiming; Ma, Ye; Zou, Yang; Wang, Xinxin; An, Zhao; Tang, Wei; Zhang, Wei; Yang, Fan; Liu, Yang; Lang, Xilong; Xu, Zhiyun; Li, Zhou; Wang, Zhong Lin

2016-07-26

Harvesting biomechanical energy in vivo is an important route in obtaining sustainable electric energy for powering implantable medical devices. Here, we demonstrate an innovative implantable triboelectric nanogenerator (iTENG) for in vivo biomechanical energy harvesting. Driven by the heartbeat of adult swine, the output voltage and the corresponding current were improved by factors of 3.5 and 25, respectively, compared with the reported in vivo output performance of biomechanical energy conversion devices. In addition, the in vivo evaluation of the iTENG was demonstrated for over 72 h of implantation, during which the iTENG generated electricity continuously in the active animal. Due to its excellent in vivo performance, a self-powered wireless transmission system was fabricated for real-time wireless cardiac monitoring. Given its outstanding in vivo output and stability, iTENG can be applied not only to power implantable medical devices but also possibly to fabricate a self-powered, wireless healthcare monitoring system.

Non-invasive cardiac output trending during exercise recovery on a bathroom-scale-based ballistocardiograph

International Nuclear Information System (INIS)

Inan, O T; Etemadi, M; Giovangrandi, L; Kovacs, G T A; Paloma, A

2009-01-01

Cardiac ejection of blood into the aorta generates a reaction force on the body that can be measured externally via the ballistocardiogram (BCG). In this study, a commercial bathroom scale was modified to measure the BCGs of nine healthy subjects recovering from treadmill exercise. During the recovery, Doppler echocardiogram signals were obtained simultaneously from the left ventricular outflow tract of the heart. The percentage changes in root-mean-square (RMS) power of the BCG were strongly correlated with the percentage changes in cardiac output measured by Doppler echocardiography (R 2 = 0.85, n = 275 data points). The correlation coefficients for individually analyzed data ranged from 0.79 to 0.96. Using Bland–Altman methods for assessing agreement, the mean bias was found to be −0.5% (±24%) in estimating the percentage changes in cardiac output. In contrast to other non-invasive methods for trending cardiac output, the unobtrusive procedure presented here uses inexpensive equipment and could be performed without the aid of a medical professional

Non-invasive cardiac output trending during exercise recovery on a bathroom-scale-based ballistocardiograph.

Science.gov (United States)

Inan, O T; Etemadi, M; Paloma, A; Giovangrandi, L; Kovacs, G T A

2009-03-01

Cardiac ejection of blood into the aorta generates a reaction force on the body that can be measured externally via the ballistocardiogram (BCG). In this study, a commercial bathroom scale was modified to measure the BCGs of nine healthy subjects recovering from treadmill exercise. During the recovery, Doppler echocardiogram signals were obtained simultaneously from the left ventricular outflow tract of the heart. The percentage changes in root-mean-square (RMS) power of the BCG were strongly correlated with the percentage changes in cardiac output measured by Doppler echocardiography (R(2) = 0.85, n = 275 data points). The correlation coefficients for individually analyzed data ranged from 0.79 to 0.96. Using Bland-Altman methods for assessing agreement, the mean bias was found to be -0.5% (+/-24%) in estimating the percentage changes in cardiac output. In contrast to other non-invasive methods for trending cardiac output, the unobtrusive procedure presented here uses inexpensive equipment and could be performed without the aid of a medical professional.

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...

Comparing Methods for Cardiac Output: Intraoperatively Doppler-Derived Cardiac Output Measured With 3-Dimensional Echocardiography Is Not Interchangeable With Cardiac Output by Pulmonary Catheter Thermodilution.

Science.gov (United States)

Graeser, Karin; Zemtsovski, Mikhail; Kofoed, Klaus F; Winther-Jensen, Matilde; Nilsson, Jens C; Kjaergaard, Jesper; Møller-Sørensen, Hasse

2018-01-09

Estimation of cardiac output (CO) is essential in the treatment of circulatory unstable patients. CO measured by pulmonary artery catheter thermodilution is considered the gold standard but carries a small risk of severe complications. Stroke volume and CO can be measured by transesophageal echocardiography (TEE), which is widely used during cardiac surgery. We hypothesized that Doppler-derived CO by 3-dimensional (3D) TEE would agree well with CO measured with pulmonary artery catheter thermodilution as a reference method based on accurate measurements of the cross-sectional area of the left ventricular outflow tract. 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 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, 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 (mean difference between methods), limits of agreement (equal to bias ± 2 standard deviations of the bias), and percentage error (limits of agreement divided by the mean of the 2 methods). Precision was determined for the individual methods (equal to 2 standard deviations of the bias between replicate measurements) to determine the acceptable limits of agreement. We found a good precision for Doppler-derived CO measured by 3D TEE, but although the bias for Doppler-derived CO by 3D compared to

High-output cardiac failure secondary to multiple vascular malformations in the liver: case report

International Nuclear Information System (INIS)

Spaner, S.; Demeter, S.; Lien, D.; Shapiro, J.; McCarthy, M.; Raymond, G.

2001-01-01

High-output cardiac failure is associated with several systemic illnesses, including hyperthyroidism, thiamine deficiency, severe anemia, multiple myeloma, Paget's disease of bone and Osler-Weber-Rendu syndrome. We present an unusual case of a woman with high-output cardiac failure as a result of multiple arteriovenous fistulas in the liver, most likely representing an unusual variant of Osler-Weber-Rendu syndrome (i.e., no other telangiectasias or a family history of vascular malformations was demonstrated). (author)

Monitoring radiation use in cardiac fluoroscopy imaging procedures

International Nuclear Information System (INIS)

Stevens, Nathaniel T.; Steiner, Stefan H.; Smith, Ian R.; MacKay, R. Jock

2011-01-01

Purpose: Timely identification of systematic changes in radiation delivery of an imaging system can lead to a reduction in risk for the patients involved. However, existing quality assurance programs involving the routine testing of equipment performance using phantoms are limited in their ability to effectively carry out this task. To address this issue, the authors propose the implementation of an ongoing monitoring process that utilizes procedural data to identify unexpected large or small radiation exposures for individual patients, as well as to detect persistent changes in the radiation output of imaging platforms. Methods: Data used in this study were obtained from records routinely collected during procedures performed in the cardiac catheterization imaging facility at St. Andrew's War Memorial Hospital, Brisbane, Australia, over the period January 2008-March 2010. A two stage monitoring process employing individual and exponentially weighted moving average (EWMA) control charts was developed and used to identify unexpectedly high or low radiation exposure levels for individual patients, as well as detect persistent changes in the radiation output delivered by the imaging systems. To increase sensitivity of the charts, we account for variation in dose area product (DAP) values due to other measured factors (patient weight, fluoroscopy time, and digital acquisition frame count) using multiple linear regression. Control charts are then constructed using the residual values from this linear regression. The proposed monitoring process was evaluated using simulation to model the performance of the process under known conditions. Results: Retrospective application of this technique to actual clinical data identified a number of cases in which the DAP result could be considered unexpected. Most of these, upon review, were attributed to data entry errors. The charts monitoring the overall system radiation output trends demonstrated changes in equipment performance

Monitoring radiation use in cardiac fluoroscopy imaging procedures

Energy Technology Data Exchange (ETDEWEB)

Stevens, Nathaniel T.; Steiner, Stefan H.; Smith, Ian R.; MacKay, R. Jock [Department of Statistics and Actuarial Sciences, Business and Industrial Statistics Research Group, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); St. Andrew' s Medical Institute, St. Andrew' s War Memorial Hospital, Brisbane, Queensland 4000 (Australia); Department of Statistics and Actuarial Sciences, Business and Industrial Statistics Research Group, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

2011-01-15

Purpose: Timely identification of systematic changes in radiation delivery of an imaging system can lead to a reduction in risk for the patients involved. However, existing quality assurance programs involving the routine testing of equipment performance using phantoms are limited in their ability to effectively carry out this task. To address this issue, the authors propose the implementation of an ongoing monitoring process that utilizes procedural data to identify unexpected large or small radiation exposures for individual patients, as well as to detect persistent changes in the radiation output of imaging platforms. Methods: Data used in this study were obtained from records routinely collected during procedures performed in the cardiac catheterization imaging facility at St. Andrew's War Memorial Hospital, Brisbane, Australia, over the period January 2008-March 2010. A two stage monitoring process employing individual and exponentially weighted moving average (EWMA) control charts was developed and used to identify unexpectedly high or low radiation exposure levels for individual patients, as well as detect persistent changes in the radiation output delivered by the imaging systems. To increase sensitivity of the charts, we account for variation in dose area product (DAP) values due to other measured factors (patient weight, fluoroscopy time, and digital acquisition frame count) using multiple linear regression. Control charts are then constructed using the residual values from this linear regression. The proposed monitoring process was evaluated using simulation to model the performance of the process under known conditions. Results: Retrospective application of this technique to actual clinical data identified a number of cases in which the DAP result could be considered unexpected. Most of these, upon review, were attributed to data entry errors. The charts monitoring the overall system radiation output trends demonstrated changes in equipment

Electro-resistive bands for non-invasive cardiac and respiration monitoring, a feasibility study

International Nuclear Information System (INIS)

Gargiulo, Gaetano D; Breen, Paul P; O’Loughlin, Aiden

2015-01-01

Continuous unobtrusive monitoring of tidal volume, particularly for critical care patients (i.e. neonates and patients in intensive care) during sleep studies and during daily activities, is still an unresolved monitoring need. Also a successful monitoring solution is yet to be proposed for continuous non-invasive cardiac stroke volume monitoring that is a novel clinical need. In this paper we present the feasibility study for a wearable, non-invasive, non-contact and unobtrusive sensor (embedded in a standard T-shirt) based on four electro-resistive bands that simultaneously monitors tidal volume and cardiac stroke volume changes. This low power sensor system (requires only 100 mW and accepts a wide power supply range up to ±18 V); thus the sensor can be easily embedded in existing wearable solutions (i.e. Holter monitors). Moreover, being contactless, it can be worn over bandages or electrodes, and as it does not rely over the integrity of the garment to work, it allows practitioners to perform procedures during monitoring. For this preliminary evaluation, one subject has worn the sensor over the period of 24 h (removing it only to shower); the accuracy of the tidal volume tested against a portable spirometer reported a precision of ±10% also during physical activity; accuracy tests for cardiac output (as it may require invasive procedure) have not been carried out in this preliminary trial. (note)

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

the effect of PPV on the central circulation by studying cardiac chamber volumes with cardiac magnetic resonance imaging (CMR). We hypothesized that PPV lowers cardiac output (CO) mainly via the Frank-Starling relationship. In 18 healthy volunteers, cardiac chamber volumes and flow in aorta and the pulmonary...... artery were measured by CMR during PPV levels of 0, 10, and 20 cmH2O applied via a respirator and a face mask. All cardiac chamber volumes decreased in proportion to the level of PPV. Following 20-cmH2O PPV, the total diastolic and systolic cardiac volumes (±SE) decreased from 605 (±29) ml to 446 (±29......) ml (P volume decreased by 27 (±4) ml/beat; heart rate increased by 7 (±2) beats/min; and CO decreased by 1.0 (±0.4) l/min (P

Non-invasive measurement of cardiac output during anaesthesia. An evaluation of the soluble gas uptake method

Energy Technology Data Exchange (ETDEWEB)

Heneghan, C.P.; Branthwaite, M.A.

1981-04-01

A technique for measuring cardiac output which depends on the uptake of an inert soluble gas from the lungs has been evaluated during anesthesia. A respiratory mass spectrometer has been used to follow the concentrations of argon and freon-22 during passive rebreathing in anaesthetized patients before cardiopulmonary bypass. Values for cardiac output obtained with this technique are reproducible, but lower than those recorded using the direct Fick technique before and after the rebreathing manoeuvre. A reduction in cardiac output caused by vigorous rebreathing is the most likely explanation for the discrepancy and, although serial measurements of oxygen consumption may permit application of a correction factor, a method of measurement which causes significant haemodynamic disturbance cannot be recommended for widespread use.

Cardiac Output and Performance during a Marathon Race in Middle-Aged Recreational Runners

OpenAIRE

Billat, Véronique L.; Petot, Hélène; Landrain, Morgan; Meilland, Renaud; Koralsztein, Jean Pierre; Mille-Hamard, Laurence

2012-01-01

Purpose. Despite the increasing popularity of marathon running, there are no data on the responses of stroke volume (SV) and cardiac output (CO) to exercise in this context. We sought to establish whether marathon performance is associated with the ability to sustain high fractional use of maximal SV and CO (i.e, cardiac endurance) and/or CO, per meter (i.e., cardiac cost). Methods. We measured the SV, heart rate (HR), CO, and running speed of 14 recreational runners in an incremental, maxima...

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

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

Directory of Open Access Journals (Sweden)

Amann Matthias

2007-11-01

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

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

Science.gov (United States)

Prasser, Christopher; Bele, Sylvia; Keyl, Cornelius; Schweiger, Stefan; Trabold, Benedikt; Amann, Matthias; Welnhofer, Julia; Wiesenack, Christoph

2007-01-01

Background Several techniques have been discussed as alternatives to the intermittent bolus thermodilution cardiac output (COPAC) measurement by the pulmonary artery catheter (PAC). However, these techniques usually require a central venous line, an additional catheter, or a special calibration procedure. A new arterial pressure-based cardiac output (COAP) device (FloTrac™, Vigileo™; Edwards Lifesciences, Irvine, CA, USA) only requires access to the radial or femoral artery using a standard arterial catheter and does not need an external calibration. We validated this technique in critically ill patients in the intensive care unit (ICU) using COPAC as the method of reference. Methods We studied 20 critically ill patients, aged 16 to 74 years (mean, 55.5 ± 18.8 years), who required both arterial and pulmonary artery pressure monitoring. COPAC measurements were performed at least every 4 hours and calculated as the average of 3 measurements, while COAP values were taken immediately at the end of bolus determinations. Accuracy of measurements was assessed by calculating the bias and limits of agreement using the method described by Bland and Altman. Results A total of 164 coupled measurements were obtained. Absolute values of COPAC ranged from 2.80 to 10.80 l/min (mean 5.93 ± 1.55 l/min). The bias and limits of agreement between COPAC and COAP for unequal numbers of replicates was 0.02 ± 2.92 l/min. The percentage error between COPAC and COAP was 49.3%. The bias between percentage changes in COPAC (ΔCOPAC) and percentage changes in COAP (ΔCOAP) for consecutive measurements was -0.70% ± 32.28%. COPAC and COAP showed a Pearson correlation coefficient of 0.58 (p < 0.01), while the correlation coefficient between ΔCOPAC and ΔCOAP was 0.46 (p < 0.01). Conclusion Although the COAP algorithm shows a minimal bias with COPAC over a wide range of values in an inhomogeneous group of critically ill patients, the scattering of the data remains relative wide. Therefore

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.

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.

Cardiac output by pulse contour analysis does not match the increase measured by rebreathing during human spaceflight.

Science.gov (United States)

Hughson, Richard L; Peterson, Sean D; Yee, Nicholas J; Greaves, Danielle K

2017-11-01

Pulse contour analysis of the noninvasive finger arterial pressure waveform provides a convenient means to estimate cardiac output (Q̇). The method has been compared with standard methods under a range of conditions but never before during spaceflight. We compared pulse contour analysis with the Modelflow algorithm to estimates of Q̇ obtained by rebreathing during preflight baseline testing and during the final month of long-duration spaceflight in nine healthy male astronauts. By Modelflow analysis, stroke volume was greater in supine baseline than seated baseline or inflight. Heart rate was reduced in supine baseline so that there were no differences in Q̇ by Modelflow estimate between the supine (7.02 ± 1.31 l/min, means ± SD), seated (6.60 ± 1.95 l/min), or inflight (5.91 ± 1.15 l/min) conditions. In contrast, rebreathing estimates of Q̇ increased from seated baseline (4.76 ± 0.67 l/min) to inflight (7.00 ± 1.39 l/min, significant interaction effect of method and spaceflight, P < 0.001). Pulse contour analysis utilizes a three-element Windkessel model that incorporates parameters dependent on aortic pressure-area relationships that are assumed to represent the entire circulation. We propose that a large increase in vascular compliance in the splanchnic circulation invalidates the model under conditions of spaceflight. Future spaceflight research measuring cardiac function needs to consider this important limitation for assessing absolute values of Q̇ and stroke volume. NEW & NOTEWORTHY Noninvasive assessment of cardiac function during human spaceflight is an important tool to monitor astronaut health. This study demonstrated that pulse contour analysis of finger arterial blood pressure to estimate cardiac output failed to track the 46% increase measured by a rebreathing method. These results strongly suggest that alternative methods not dependent on pulse contour analysis are required to track cardiac function in spaceflight

The correlation between the first heart sound and cardiac output as measured by using digital esophageal stethoscope under anaesthesia.

Science.gov (United States)

Duck Shin, Young; Hoon Yim, Kyoung; Hi Park, Sang; Wook Jeon, Yong; Ho Bae, Jin; Soo Lee, Tae; Hwan Kim, Myoung; Jin Choi, Young

2014-03-01

The use of an esophageal stethoscope is a basic heart sounds monitoring procedure performed in patients under general anesthesia. As the size of the first heart sound can express the left ventricle function, its correlation with cardiac output should be investigated. The aim of this study was to investigate the effects of cardiac output (CO) on the first heart sound (S1) amplitude. Methods : Six male beagles were chosen. The S1 was obtained with the newly developed esophageal stethoscope system. CO was measured using NICOM, a non-invasive CO measuring device. Ephedrine and beta blockers were administered to the subjects to compare changes in figures, and the change from using an inhalation anesthetic was also compared. The S1 amplitude displayed positive correlation with the change rate of CO (r = 0.935, p < 0.001). The heart rate measured using the esophageal stethoscope and ECG showed considerably close figures through the Bland-Altman plot and showed a high positive correlation (r = 0.988, p < 0,001). In beagles, the amplitude of S1 had a significant correlation with changes in CO in a variety of situations.

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.

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

A comparison of dobutamine and levosimendan on hepatic blood flow in patients with a low cardiac output state after cardiac surgery: a randomised controlled study.

Science.gov (United States)

Alvarez, J; Baluja, A; Selas, S; Otero, P; Rial, M; Veiras, S; Caruezo, V; Taboada, M; Rodriguez, I; Castroagudin, J; Tome, S; Rodriguez, A; Rodriguez, J

2013-11-01

Liver dysfunction due to a low cardiac output state after cardiac surgery is associated with a poor prognosis, but whether one inotrope is superior to another in improving hepatic perfusion remains uncertain. This study compared the systemic and hepatic haemodynamic effects of levosimendan to dobutamine in patients with a low cardiac output state (cardiac index flow (ml/min): 614.0±124.7, 585.9±144.8; pulsatility index: 2.02±0,28, 2.98±0.27 versus the levosimendan group: cardiac index: 3.02± 0.27, 2.98± 0.30; portal vein flow: 723.0± 143.5, 702.9±117.8; pulsatility index: 1.71±0.26, 1.73±0.27). The improvement in portal vein blood flow at 48 hours was significantly better after levosimendan than dobutamine (41% vs. 11% increment from baseline, Pflow through both the hepatic artery and portal venous system, whereas dobutamine can only improve the portal venous blood flow without vasodilating the hepatic artery.

Clinical skills: cardiac rhythm recognition and monitoring.

Science.gov (United States)

Sharman, Joanna

With technological advances, changes in provision of healthcare services and increasing pressure on critical care services, ward patients' severity of illness is ever increasing. As such, nurses need to develop their skills and knowledge to care for their client group. Competency in cardiac rhythm monitoring is beneficial to identify changes in cardiac status, assess response to treatment, diagnosis and post-surgical monitoring. This paper describes the basic anatomy and physiology of the heart and its conduction system, and explains a simple and easy to remember process of analysing cardiac rhythms (Resuscitation Council UK, 2000) that can be used in first-line assessment to assist healthcare practitioners in providing care to their patients.

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.

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

Noninvasive pulse contour analysis for determination of cardiac output in patients with chronic heart failure.

Science.gov (United States)

Roth, Sebastian; Fox, Henrik; Fuchs, Uwe; Schulz, Uwe; Costard-Jäckle, Angelika; Gummert, Jan F; Horstkotte, Dieter; Oldenburg, Olaf; Bitter, Thomas

2018-05-01

Determination of cardiac output (CO) is essential in diagnosis and management of heart failure (HF). The gold standard to obtain CO is invasive assessment via thermodilution (TD). Noninvasive pulse contour analysis (NPCA) is supposed as a new method of CO determination. However, a validation of this method in HF is pending and performed in the present study. Patients with chronic-stable HF and reduced left ventricular ejection fraction (LVEF ≤ 45%; HF-REF) underwent right heart catheterization including TD. NPCA using the CNAP Monitor (V5.2.14, CNSystems Medizintechnik AG) was performed simultaneously. Three standardized TD measurements were compared with simultaneous auto-calibrated NPCA CO measurements. In total, 84 consecutive HF-REF patients were enrolled prospectively in this study. In 4 patients (5%), TD was not successful and for 22 patients (26%, 18 with left ventricular assist device), no NPCA signal could be obtained. For the remaining 58 patients, Bland-Altman analysis revealed a mean bias of + 1.92 L/min (limits of agreement ± 2.28 L/min, percentage error 47.4%) for CO. With decreasing cardiac index, as determined by the gold standard of TD, there was an increasing gap between CO values obtained by TD and NPCA (r = - 0.75, p TD-CI classified 52 (90%) patients to have a reduced CI (REF patients, auto-calibrated NPCA systematically overestimates CO with decrease in cardiac function. Therefore, to date, NPCA cannot be recommended in this cohort.

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....

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...

Electrical Cardiometry to Monitor Cardiac Output in Preterm Infants with Patent Ductus Arteriosus: A Comparison with Echocardiography.

Science.gov (United States)

Hsu, Kai-Hsiang; Wu, Tai-Wei; Wu, I-Hsyuan; Lai, Mei-Yin; Hsu, Shih-Yun; Huang, Hsiao-Wen; Mok, Tze-Yee; Lien, Reyin

2017-01-01

Electrical cardiometry (EC) is an impedance-based monitoring that provides noninvasive cardiac output (CO) assessment. Through comparison to transthoracic echocardiography (Echo), the accuracy of EC has been verified. However, left-to-right patent ductus arteriosus (PDA) shunting is a concern because PDA shunts aortic flow to the pulmonary artery and may interfere with EC in measuring CO. To determine the agreement between EC and Echo in preterm infants with a hemodynamically significant PDA (hsPDA). We reviewed our hemodynamic database in which simultaneous CO measurements by Echo and EC (Aesculon®) were recorded. Preterm infants with left-to-right shunting hsPDA were enrolled. A total of 105 paired measurements in 36 preterm infants were compared. Infants' median (range) age and weight at measurement were 27+2 weeks (24+0-33+1) and 1,015 g (518-1,880), with mean (95% CI) ductal diameter 2.11 mm (1.99-2.22) or 2.15 mm/kg (2.00-2.30). Mean COEC and COEcho were 252 ± 32 and 258 ± 45 mL/kg/min, respectively, which demonstrated a moderate correlation and without a significant between-measurement difference. Bland-Altman analysis showed a bias, limits of agreement, and error percentage of -5.3 mL/kg/min, -78.3 to 67.7 mL/kg/min, and 28.6%, respectively. There was a trend of increased bias and error percentage of infants with high CO ≥280 mL/kg/min and supported with high-frequency ventilator. EC and Echo have a wide but clinically acceptable agreement in measuring CO in preterm infants with hsPDA. However, for infants with high CO or ventilated by high-frequency ventilation, interpretation of COEC should be approached with caution. © 2017 S. Karger AG, Basel.

Relationship between stroke volume, cardiac output and filling of the heart during tilt

DEFF Research Database (Denmark)

Bundgaard-Nielsen, M.; Sorensen, H.; Dalsgaard, M.

2009-01-01

. With the supine resting position as a reference, we assessed stroke volume (SV), cardiac output (CO) and filling of the heart during graded tilt to evaluate whether SV and CO are maintained during an assumed maximal physiological filling of the heart elicited by 90 degrees HDT in healthy resting humans. METHODS...

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.

Remote Monitoring of Cardiac Implantable Electronic Devices.

Science.gov (United States)

Cheung, Christopher C; Deyell, Marc W

2018-01-08

Over the past decade, technological advancements have transformed the delivery of care for arrhythmia patients. From early transtelephonic monitoring to new devices capable of wireless and cellular transmission, remote monitoring has revolutionized device care. In this article, we review the current evolution and evidence for remote monitoring in patients with cardiac implantable electronic devices. From passive transmission of device diagnostics, to active transmission of patient- and device-triggered alerts, remote monitoring can shorten the time to diagnosis and treatment. Studies have shown that remote monitoring can reduce hospitalization and emergency room visits, and improve survival. Remote monitoring can also reduce the health care costs, while providing increased access to patients living in rural or marginalized communities. Unfortunately, as many as two-thirds of patients with remote monitoring-capable devices do not use, or are not offered, this feature. Current guidelines recommend remote monitoring and interrogation, combined with annual in-person evaluation in all cardiac device patients. Remote monitoring should be considered in all eligible device patients and should be considered standard of care. Copyright © 2018 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

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.

Cardiac output and performance during a marathon race in middle-aged recreational runners.

Science.gov (United States)

Billat, Véronique L; Petot, Hélène; Landrain, Morgan; Meilland, Renaud; Koralsztein, Jean Pierre; Mille-Hamard, Laurence

2012-01-01

Despite the increasing popularity of marathon running, there are no data on the responses of stroke volume (SV) and cardiac output (CO) to exercise in this context. We sought to establish whether marathon performance is associated with the ability to sustain high fractional use of maximal SV and CO (i.e, cardiac endurance) and/or CO, per meter (i.e., cardiac cost). We measured the SV, heart rate (HR), CO, and running speed of 14 recreational runners in an incremental, maximal laboratory test and then during a real marathon race (mean performance: 3 hr 30 min ± 45 min). Our data revealed that HR, SV and CO were all in a high but submaximal steady state during the marathon (87.0 ± 1.6%, 77.2 ± 2.6%, and 68.7 ± 2.8% of maximal values, respectively). Marathon performance was inversely correlated with an upward drift in the CO/speed ratio (mL of CO × m(-1)) (r = -0.65, P marathon performance is inversely correlated with cardiac cost and positively correlated with cardiac endurance. The CO response could be a benchmark for race performance in recreational marathon runners.

Consenso brasileiro de monitorização e suporte hemodinâmico - parte III: métodos alternativos de monitorização do débito cardíaco e da volemia Brazilian consensus of monitoring and hemodynamic support - part III: alternative methods for cardiac output monitoring and volemia estimation

Directory of Open Access Journals (Sweden)

Guilherme Schettino

2006-03-01

Full Text Available JUSTIFICATIVA E OBJETIVOS: A interpretação do débito cardíaco e da pré-carga como números absolutos não traz grandes informações sobre a hemodinâmica do paciente crítico. Em contrapartida, a monitorização da resposta do débito cardíaco à expansão volêmica ou suporte inotrópico é uma ferramenta muito útil na unidade de terapia intensiva, quando o paciente apresenta algum sinal de má perfusão tecidual. Apesar do CAP ser considerado como " padrão-ouro" na avaliação destes parâmetros, foram desenvolvidas tecnologias alternativas bastante confiáveis para a sua monitorização. MÉTODO: O processo de desenvolvimento de recomendações utilizou o método Delphi modificado para criar e quantificar o consenso entre os participantes. A AMIB determinou um coordenador para o consenso, o qual escolheu seis especialistas para comporem o comitê consultivo. Outros 18 peritos de diferentes regiões do país foram selecionados para completar o painel de 25 especialistas, médicos e enfermeiros. Um levantamento bibliográfico na MEDLINE de artigos na língua inglesa foi realizado no período de 1966 a 2004. RESULTADOS: Foram apresentadas recomendações referentes à análise da variação da pressão arterial durante ventilação mecânica, débito cardíaco contínuo por contorno de pulso arterial, débito cardíaco por diluição do lítio, Doppler transesofágico, bioimpedância transtorácica, ecocardiografia e reinalação parcial de gás carbônico. CONCLUSÕES: As novas e menos invasivas técnicas para medida do débito cardíaco, pré-carga e fluidoresponsividade apresentam adequada precisão e podem ser uma alternativa ao uso do CAP em pacientes graves.BACKGROUND AND OBJECTIVES: Cardiac output and preload as absolute data do not offer helpful information about the hemodynamic of critically ill patients. However, monitoring the response of these variables to volume challenge or inotropic drugs is a very useful tool in the

Optimizing Cardiac Out-Put to Increase Cerebral Penumbral Perfusion in Large Middle Cerebral Artery Ischemic Lesion—OPTIMAL Study

Directory of Open Access Journals (Sweden)

Hannah Fuhrer

2017-08-01

Full Text Available IntroductionIn unsuccessful vessel recanalization, clinical outcome of acute stroke patients depends on early improvement of penumbral perfusion. So far, mean arterial blood pressure (MAP is the target hemodynamic parameter. However, the correlations of MAP to cardiac output (CO and cerebral perfusion are volume state dependent. In severe subarachnoid hemorrhage, optimizing CO leads to a reduction of delayed ischemic neurological deficits and improvement of clinical outcome. This study aims to investigate the effect of standard versus advanced cardiac monitoring with optimization of CO on the clinical outcome in patients with large ischemic stroke.Methods and analysisThe OPTIMAL study is a prospective, multicenter, open, into two arms (1:1 randomized, controlled trial. Sample size estimate: sample sizes of 150 for each treatment group (300 in total ensure an 80% power to detect a difference of 16% of a dichotomized level of functional clinical outcome at 3 months at a significance level of 0.05. Study outcomes: the primary endpoint is the functional outcome at 3 months. The secondary endpoints include functional outcome at 6 months follow-up, and complications related to hemodynamic monitoring and therapies.DiscussionThe results of this trial will provide data on the safety and efficacy of advanced hemodynamic monitoring on clinical outcome.Ethics and disseminationThe trial was approved by the leading ethics committee of Freiburg University, Germany (438/14, 2015 and the local ethics committees of the participating centers. The study is performed in accordance with the Declaration of Helsinki and the guidelines of Good Clinical Practice. It is registered in the German Clinical Trial register (DRKS; DRKS00007805. Dissemination will include submission to peer-reviewed professional journals and presentation at congresses. Hemodynamic monitoring may be altered in a specific stroke patient cohort if the study shows that advanced monitoring is

Individual differences in episodic memory abilities predict successful prospective memory output monitoring.

Science.gov (United States)

Hunter Ball, B; Pitães, Margarida; Brewer, Gene A

2018-02-07

Output monitoring refers to memory for one's previously completed actions. In the context of prospective memory (PM) (e.g., remembering to take medication), failures of output monitoring can result in repetitions and omissions of planned actions (e.g., over- or under-medication). To be successful in output monitoring paradigms, participants must flexibly control attention to detect PM cues as well as engage controlled retrieval of previous actions whenever a particular cue is encountered. The current study examined individual differences in output monitoring abilities in a group of younger adults differing in attention control (AC) and episodic memory (EM) abilities. The results showed that AC ability uniquely predicted successful cue detection on the first presentation, whereas EM ability uniquely predicted successful output monitoring on the second presentation. The current study highlights the importance of examining external correlates of PM abilities and contributes to the growing body of research on individual differences in PM.

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.

Beat-by-beat analysis of cardiac output and blood pressure responses to short-term barostimulation in different body positions

Science.gov (United States)

Hildebrandt, Wulf; Schütze, Harald; Stegemann, J.

Rapid quantification of the human baro-reflex control of heart rate has been achieved on a beat-by-beat basis using a neck-chamber with quick ECG-triggered pressure changes. Referring to recent findings on heart rate and stroke volume, the present study uses this technique to compare cardiac output as well as blood pressure changes in supine and upright position to investigate feedback effects and to confirm postural reflex modifications not revealed by RR-interval changes. A suction profile starting at +40 mmHg and running 7 steps of pressure decrease down to -65 mmHg was examined in 0° and 90° tilting position while beat-by-beat recordings were done of heart rate, stroke volume (impedance-cardiography) and blood pressure (Finapres tm) (n=16). The percentual heart rate decrease failed to be significantly different between positions. A suction-induced stroke volume increase led to a cardiac output almost maintained when supine and significantly increased when upright. A decrease in all blood pressure values was found during suction, except for systolic values in upright position which increased. Conclusively, (a) it is confirmed that different inotropy accounts for the seen gravitational effect on the cardiac output not represented by heart rate; (b) identical suction levels in different positions lead to different stimuli at the carotid receptor. This interference has to be considered in microgravity studies by beat-by-beat measurement of cardiac output and blood pressure.

Non-invasive measurements of cardiac output in atrial fibrillation: Inert gas rebreathing and impedance cardiography

DEFF Research Database (Denmark)

Osbak, Philip S; Henriksen, Jens Henrik Sahl; Kofoed, Klaus F

2011-01-01

Abstract Background. Atrial fibrillation (AF) is associated with significant morbidity and mortality. To test the effect of interventions, knowledge of cardiac output (CO) is important. However, the irregular heart rate might cause some methods for determination of CO to have inherent weaknesses....

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...

Chronic resuscitation after trauma-hemorrhage and acute fluid replacement improves hepatocellular function and cardiac output.

Science.gov (United States)

Remmers, D E; Wang, P; Cioffi, W G; Bland, K I; Chaudry, I H

1998-01-01

To determine whether prolonged (chronic) resuscitation has any beneficial effects on cardiac output and hepatocellular function after trauma-hemorrhage and acute fluid replacement. Acute fluid resuscitation after trauma-hemorrhage restores but does not maintain the depressed hepatocellular function and cardiac output. Male Sprague-Dawley rats underwent a 5-cm laparotomy (i.e., trauma was induced) and were bled to and maintained at a mean arterial pressure of 40 mmHg until 40% of maximal bleed-out volume was returned in the form of Ringer's lactate (RL). The animals were acutely resuscitated with RL using 4 times the volume of maximum bleed-out over 60 minutes, followed by chronic resuscitation of 0, 5, or 10 mL/kg/hr RL for 20 hours. Hepatocellular function was determined by an in vivo indocyanine green clearance technique. Hepatic microvascular blood flow was assessed by laser Doppler flowmetry. Plasma levels of interleukin-6 (IL-6) were determined by bioassay. Chronic resuscitation with 5 mL/kg/hr RL, but not with 0 or 10 mL/kg/hr RL, restored cardiac output, hepatocellular function, and hepatic microvascular blood flow at 20 hours after hemorrhage. The regimen above also reduced plasma IL-6 levels. Because chronic resuscitation with 5 mL/kg/hr RL after trauma-hemorrhage and acute fluid replacement restored hepatocellular function and hepatic microvascular blood flow and decreased plasma levels of IL-6, we propose that chronic fluid resuscitation in addition to acute fluid replacement should be routinely used in experimental studies of trauma-hemorrhage.

Comparing Methods for Cardiac Output

DEFF Research Database (Denmark)

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

2018-01-01

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...... 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......, 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...

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

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.

Cardiac Output and Performance during a Marathon Race in Middle-Aged Recreational Runners

Directory of Open Access Journals (Sweden)

Véronique L. Billat

2012-01-01

Full Text Available Purpose. Despite the increasing popularity of marathon running, there are no data on the responses of stroke volume (SV and cardiac output (CO to exercise in this context. We sought to establish whether marathon performance is associated with the ability to sustain high fractional use of maximal SV and CO (i.e, cardiac endurance and/or CO, per meter (i.e., cardiac cost. Methods. We measured the SV, heart rate (HR, CO, and running speed of 14 recreational runners in an incremental, maximal laboratory test and then during a real marathon race (mean performance: 3 hr 30 min ± 45 min. Results. Our data revealed that HR, SV and CO were all in a high but submaximal steady state during the marathon (87.0 ± 1.6%, 77.2 ± 2.6%, and 68.7 ± 2.8% of maximal values, respectively. Marathon performance was inversely correlated with an upward drift in the CO/speed ratio (mL of CO×m−1 (r=−0.65, P<0.01 and positively correlated with the runner’s ability to complete the race at a high percentage of the speed at maximal SV (r=0.83, P<0.0002. Conclusion. Our results showed that marathon performance is inversely correlated with cardiac cost and positively correlated with cardiac endurance. The CO response could be a benchmark for race performance in recreational marathon runners.

Study on cardiac output in children with orthostatic disturbances measured by the external dilution method with a radioisotope

Energy Technology Data Exchange (ETDEWEB)

Hattori, K [Nippon Medical School, Tokyo

1975-04-01

As one of the studies on circulation dynamics which possibly contributed to orthostatic disturbance, application to children of the external measurement of cardiac output with /sup 131/I labeled human serum albumin was examined. The effect of orthostatic load was then studied by this method on the children with orthostatic disturbances and the patients improving from other diseases, and the following results were obtained: (1) As in the external method with radioisotope, the head of the scintillation detector was easily oriented, and the diversion of orientation was examined by circulation dilution curve, and the cardiac output was easily and safely measured without causing severe pain to the subjects. This method was performed on 40 children in the recumbent position and 27 in orthostatic load, and it was confirmed that the method was fully applicable to the pediatric field. (2) In half of the 20 patients with orthostatic disturbances and 20 control subjects, the cardiac index in the recumbent position was between 3 l/min/m/sup 2/ and 5 l/min/m/sup 2/. Mean cardiac index was 4.45 l/min/m/sup 2/ in male children, while 4.72 l/min/m/sup 2/ in female children. This mean value was the same or a little higher than the reported adult value.

The effect of halothane on the distribution of cardiac output and organ blood flows in the hemorrhagic, hypotensive dog

International Nuclear Information System (INIS)

Ahlgren, I.; Aronsen, K.F.; Bjoerkman, I.

1978-01-01

Halothane was given to dogs which had been bled to an arterial mean blood pressure of 60 mmHg, and the circulatory effects were studied with the aid of the radioactive microsphere technique. The cardiac output and coronary blood flow were well maintained, whereas the arterial mean blood pressure was slightly, and the stroke volume markedly increased, indicating an improved heart function. The blood flows to the brain, lungs, liver and kidneys were well preserved throughout the anesthesia. The effect of retransfusing the withdrawn blood was also studied, and it resulted in an increased cardiac output, arterial mean blood pressure and increased blood flows to the heart, lungs, spleen, bowel and liver. (author)

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

PURPOSE: To assess the benefits and harms of levosimendan for low cardiac output syndrome in critically ill patients. METHODS: We conducted a systematic review with meta-analyses and trial sequential analyses (TSA) of randomised clinical trials comparing levosimendan with any type of control. Two...... 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...

Decreased 2,3-diphosphoglycerate concentration in low cardiac output patients and its influence on the determination of in vivo p50.

Science.gov (United States)

Piccioni, Marilde A; Cestari, Idágene A; Strunz, Célia M C; Auler, José O

2003-08-01

We investigated whether 2,3-diphosphoglycerate (2,3-DPG) is altered in patients with low cardiac output and the influence of its concentration on the calculation of in vivo P(50). Biochemical and blood gas analysis were performed along with the measurement of cardiac output and body temperature in 13 patients submitted to cardiopulmonary bypass surgeries without the use of donor blood. In vivo P(50) was calculated using the measured (P(50m)) and the estimated 2,3-DPG (P(50e)). 2,3-DPG concentration was lower in these patients when compared to the values obtained in normal volunteers (6.9 +/- 2.2 vs. 11.9 +/- 2.4 microm/gHb). P(50m) was lower than P(50e) (21.6 +/- 1.1 vs. 30.1 +/- 1.2 mm Hg) at all time points. Our data show that in patients with low cardiac output, 2,3-DPG concentration is reduced. Therefore, in these patients, the use of standard values for this variable may introduce an error in the calculation of in vivo P(50).

Monitor of cardiac events implemented in PDA platform

International Nuclear Information System (INIS)

Bustamante, John; Saenz, Jose F; Amaya, Adrian

2007-01-01

Ambulatory monitoring of electrocardiac events constitutes a valuable tool in the diagnosis of cardiac arrhythmias involved in pathologic processes such as myocardiopathies, post-infarction stages, autonomous cardiac system injuries, etc.; unfortunately, its extensive use is not possible yet, due to the high costs that imply the acquisition of these equipment. For this purpose, through the utilization of personal digital assistants, a monitor of cardiac events with pre and post-symptomatic recording capacity, electrocardiographic signal visualization in real time, automatic recording of bradycardias and tachycardias and the possibility of annotation of symptoms by the patient, is designed and developed. It consists of a hardware component for the acquisition and treatment of the signals, software for the monitoring in Palm OSO platform and an appliance for the discharge and analysis of the stored data. Prototype validations were realized through an electrocardiographic simulator, an arrhythmia simulator Based on arrhythmia data base registers of the Massachusetts Institute of Technology and 8eth Israel Hospital and on pilot tests of healthy people and of patients with arrhythmias. In this preliminary report, we show the way in which the developed prototype constitutes a viable alternative for ambulatory monitoring of arrhythmia, taking advantages of the storage capacity, processing and visualization that have the actual digital assistances with the additional advantages that its use is not restricted to only one utility and its economic accessibility is facilitated due to its wide commercial availability

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...

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.

[Design and application of user managing system of cardiac remote monitoring network].

Science.gov (United States)

Chen, Shouqiang; Zhang, Jianmin; Yuan, Feng; Gao, Haiqing

2007-12-01

According to inpatient records, data managing demand of cardiac remote monitoring network and computer, this software was designed with relative database ACCESS. Its interface, operational button and menu were designed in VBA language assistantly. Its design included collective design, amity, practicability and compatibility. Its function consisted of registering, inquiring, statisticing and printing, et al. It could be used to manage users effectively and could be helpful to exerting important action of cardiac remote monitoring network in preventing cardiac-vascular emergency ulteriorly.

Ubiquitous health monitoring and real-time cardiac arrhythmias detection: a case study.

Science.gov (United States)

Li, Jian; Zhou, Haiying; Zuo, Decheng; Hou, Kun-Mean; De Vaulx, Christophe

2014-01-01

As the symptoms and signs of heart diseases that cause sudden cardiac death, cardiac arrhythmia has attracted great attention. Due to limitations in time and space, traditional approaches to cardiac arrhythmias detection fail to provide a real-time continuous monitoring and testing service applicable in different environmental conditions. Integrated with the latest technologies in ECG (electrocardiograph) analysis and medical care, the pervasive computing technology makes possible the ubiquitous cardiac care services, and thus brings about new technical challenges, especially in the formation of cardiac care architecture and realization of the real-time automatic ECG detection algorithm dedicated to care devices. In this paper, a ubiquitous cardiac care prototype system is presented with its architecture framework well elaborated. This prototype system has been tested and evaluated in all the clinical-/home-/outdoor-care modes with a satisfactory performance in providing real-time continuous cardiac arrhythmias monitoring service unlimitedly adaptable in time and space.

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 ...

The non-invasive and continuous estimation of cardiac output using a photoplethysmogram and electrocardiogram during incremental exercise

International Nuclear Information System (INIS)

Wang, L; Poon, C C Y; Zhang, Y T

2010-01-01

Cardiac output (CO) monitoring is not only essential for critically ill patients in the hospital, but also for patients at home and those undergoing cardiopulmonary exercise testing. However, CO is difficult to monitor during daily activities and exercise. In this paper, we aim at developing a novel CO estimation method that can be used under these challenging conditions. The tube model was utilized to derive a CO index, namely the pulse time reflection ratio (PTRR) from an electrocardiogram and photoplethysmogram. After calibration, the PTRR can be used to estimate beat-to-beat CO. The proposed method was verified against CO measured by impedance cardiography on 19 healthy subjects in an incremental intensity exercise test. Results showed that there were strong correlations (r) between the PTRR and reference CO in 18 subjects (mean r: 0.88, n = 245 trials). Two calibration approaches reported in the literature were applied to the proposed method and the corresponding bias ± precisions of estimation errors were 0 ± 1.89 L min −1 and −0.22 ± 2.12 L min −1 , respectively. The percent errors were 21.94% and 24.90%, smaller than the clinical acceptance limit (30%). To conclude, after calibration, this method can be used to monitor CO on healthy subjects during incremental intensity exercise

Continuous Glucose Monitoring in the Cardiac ICU: Current Use and Future Directions.

Science.gov (United States)

Scrimgeour, Laura A; Potz, Brittany A; Sellke, Frank W; Abid, M Ruhul

2017-11-01

Perioperative glucose control is highly important, particularly for patients undergoing cardiac surgery. Variable glucose levels before, during and after cardiac surgery lead to increased post-operative complications and patient mortality. [1] Current methods for intensive monitoring and treating hyperglycemia in the Intensive Care Unit (ICU) usually involve hourly glucose monitoring and continuous intravenous insulin infusions. With the advent of more accurate subcutaneous glucose monitoring systems, the role of improved glucose control with newer systems deserves consideration for widespread adoption.

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...... normothermic is no longer adequate during a heat-stressed-simulated hemorrhage. The absence of a decrease in SVC at a time of profound reductions in MAP suggests that inadequate control of vascular conductance is a primary mechanism compromising blood pressure control during these conditions....

Ventilation and gas exchange management after cardiac arrest.

Science.gov (United States)

Sutherasan, Yuda; Raimondo, Pasquale; Pelosi, Paolo

2015-12-01

For several decades, physicians had integrated several interventions aiming to improve the outcomes in post-cardiac arrest patients. However, the mortality rate after cardiac arrest is still as high as 50%. Post-cardiac arrest syndrome is associated with high morbidity and mortality due to not only poor neurological outcome and cardiovascular failure but also respiratory dysfunction. To minimize ventilator-associated lung injury, protective mechanical ventilation by using low tidal volume ventilation and driving pressure may decrease pulmonary complications and improve survival. Low level of positive end-expiratory pressure (PEEP) can be initiated and titrated with careful cardiac output and respiratory mechanics monitoring. Furthermore, optimizing gas exchange by avoiding hypoxia and hyperoxia as well as maintaining normocarbia may improve neurological and survival outcome. Early multidisciplinary cardiac rehabilitation intervention is recommended. Minimally invasive monitoring techniques, that is, echocardiography, transpulmonary thermodilution method measuring extravascular lung water, as well as transcranial Doppler ultrasound, might be useful to improve appropriate management of post-cardiac arrest patients. Copyright © 2015 Elsevier Ltd. All rights reserved.

STEM promotion through museum exhibits on cardiac monitoring & cardiac rhythm management.

Science.gov (United States)

Countryman, Jordan D; Dow, Douglas E

2014-01-01

Formal education in science, technology, engineering and math (STEM) does not successfully engage all of the students who have potential to become skilled in STEM activities and careers. Museum exhibits may be able to reach and engage a broader range of the public. STEM Exhibits that are both understandable and capture the imagination of viewers may contribute toward increased interest in STEM activities. One such topic for such an exhibit could be cardiac pacemakers and cardioverter defibrillators that sustain life. Although museums have existed for centuries, the available types of exhibit designs has dramatically increased in recent decades due to innovations in technology. Science and technology museums have especially taken advantage of the progression of exhibit design to developed new ways to communicate to their viewers. These novel presentation tools allow museums to more effectively convey to and engage viewers. This paper examines the techniques employed by museums in exhibits and considers the practices of several museums with exhibits related to cardiac monitoring (CM) and cardiac rhythm management (CRM).

Invasive hemodynamic monitoring in the postoperative period of cardiac surgery

Directory of Open Access Journals (Sweden)

Desanka Dragosavac

1999-08-01

Full Text Available OBJETIVE: To assess the hemodynamic profile of cardiac surgery patients with circulatory instability in the early postoperative period (POP. METHODS: Over a two-year period, 306 patients underwent cardiac surgery. Thirty had hemodynamic instability in the early POP and were monitored with the Swan-Ganz catheter. The following parameters were evaluated: cardiac index (CI, systemic and pulmonary vascular resistance, pulmonary shunt, central venous pressure (CVP, pulmonary capillary wedge pressure (PCWP, oxygen delivery and consumption, use of vasoactive drugs and of circulatory support. RESULTS: Twenty patients had low cardiac index (CI, and 10 had normal or high CI. Systemic vascular resistance was decreased in 11 patients. There was no correlation between oxygen delivery (DO2 and consumption (VO2, p=0.42, and no correlation between CVP and PCWP, p=0.065. Pulmonary vascular resistance was decreased in 15 patients and the pulmonary shunt was increased in 19. Two patients with CI < 2L/min/m² received circulatory support. CONCLUSION: Patients in the POP of cardiac surgery frequently have a mixed shock due to the systemic inflammatory response syndrome (SIRS. Therefore, invasive hemodynamic monitoring is useful in handling blood volume, choice of vasoactive drugs, and indication for circulatory support.

Complications after implantation of a new-generation insertable cardiac monitor

DEFF Research Database (Denmark)

Diederichsen, Søren Zöga; Haugan, Ketil Jørgen; Højberg, Søren

2017-01-01

BACKGROUND: Insertable cardiac monitors (ICM) are leadless devices utilized in long-term monitoring of the heart rhythm. The implantation procedure of the new-generation ICMs is minimally invasive, but little experience exists regarding complications. We thus aimed to investigate adverse events (AE...

Monitoring Linear Accelerator Output Constancy Using the PTW Linacheck

International Nuclear Information System (INIS)

McDermott, Garry M.; Buckle, Andrew H.

2011-01-01

The PTW-Linacheck was assessed for its ability to monitor linear accelerator radiation output constancy. The key issues that were considered were the setup for daily output measurements, e.g., requirements for build-up and backscatter material, and the reproducibility and linearity of the device with linear accelerator output. An appropriate measurement setup includes a 10 x 10 cm field at 100 cm FSD, 5 cm backscatter, and no added build-up for 4 MeV electron beams, 1 cm added build-up for 6-16 MeV electron beams and 5 cm added build-up for 6-15 MV photon beams. Using this measurement setup, the dose linearity and short-term reproducibility were acceptable; however, the Linacheck should be recalibrated on a monthly basis to ensure acceptable long-term reproducibility.

Electrocardiographic Patch Devices and Contemporary Wireless Cardiac Monitoring

Directory of Open Access Journals (Sweden)

Erik eFung

2015-05-01

Full Text Available Cardiac electrophysiologic derangements often coexist with disorders of the circulatory system. Capturing and diagnosing arrhythmias and conduction system disease may lead to a change in diagnosis, clinical management and patient outcomes. Standard 12-lead electrocardiogram (ECG, Holter monitors and event recorders have served as useful diagnostic tools over the last few decades. However, their shortcomings are only recently being addressed by emerging technologies. With advances in device miniaturization and wireless technologies, and changing consumer expectations, wearable ‘on-body’ ECG patch devices have evolved to meet contemporary needs. These devices are unobtrusive and easy to use, leading to increased device wear time and diagnostic yield. While becoming the standard for detecting arrhythmias and conduction system disorders in the outpatient setting where continuous ECG monitoring in the short to medium term (days to weeks is indicated, these cardiac devices and related digital mobile health technologies are reshaping the clinician-patient interface with important implications for future healthcare delivery.

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.

Ubiquitous computing for remote cardiac patient monitoring: a survey.

Science.gov (United States)

Kumar, Sunil; Kambhatla, Kashyap; Hu, Fei; Lifson, Mark; Xiao, Yang

2008-01-01

New wireless technologies, such as wireless LAN and sensor networks, for telecardiology purposes give new possibilities for monitoring vital parameters with wearable biomedical sensors, and give patients the freedom to be mobile and still be under continuous monitoring and thereby better quality of patient care. This paper will detail the architecture and quality-of-service (QoS) characteristics in integrated wireless telecardiology platforms. It will also discuss the current promising hardware/software platforms for wireless cardiac monitoring. The design methodology and challenges are provided for realistic implementation.

Cardiac gated ventilation

International Nuclear Information System (INIS)

Hanson, C.W. III; Hoffman, E.A.

1995-01-01

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. The authors 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 50 msec scan aperture. Multi slice, 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. The authors observed an increase in cardiac output of up to 30% with inspiration gated to the systolic phase of the cardiac cycle in a non-failing model of the heart

Nasal continuous positive airway pressure (n-CPAP) does not change cardiac output in preterm infants.

Science.gov (United States)

Moritz, Barbara; Fritz, Michael; Mann, Christian; Simma, Burkhard

2008-02-01

Our objective was to study how invasive mechanical ventilation impairs cardiac output (CO) in children and adults. Although the application of continuous positive airway pressure (CPAP) is widely practiced in neonatal intensive care, its hemodynamic consequences have not yet been investigated. A prospective study to assess the hemodynamic effects was conducted in 21 preterm infants CPAP (n-CPAP). Gestational age was 28.0 +/- 1.9 weeks (mean +/- standard deviation); birthweight, 1000 +/- 238 g; age at study entry, 200 +/- 155 hours; total maintenance fluid, 154 +/- 42 mL/kg/day; and n-CPAP level, 4.4 +/- 0.9 cm H(2)O. None of the infants received inotropic support, and n-CPAP did not cause any significant difference in the parameters measured: stroke volume, 3.1 +/- 1.0 mL (with n-CPAP) versus 3.1 +/- 1.0 mL (without n-CPAP); cardiac output, 487 +/- 156 mL/minute versus 500 +/- 176 mL/minute; left ventricular diastolic diameter, 1.22 +/- 0.15 cm versus 1.24 +/- 0.14 cm; fractional shortening, 0.30 +/- 0.05% versus 0.29 +/- 0.04%; and aortic velocity-time integral, 8.64 +/- 1.80 cm versus 8.70 +/- 1.65 cm. The n-CPAP level did not influence CO; n-CPAP (up to 7 cm H (2)O) has no echocardiographically detectable hemodynamic effect in preterm infants. Our data imply there is no need to withhold n-CPAP support to prevent circulatory compromise in these infants.

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.

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.

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.

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

Indexation of cardiac output to biometric parameters in critically ill patients: A systematic analysis of a transpulmonary thermodilution-derived database.

Science.gov (United States)

Saugel, Bernd; Mair, Sebastian; Götz, Simon Q; Tschirdewahn, Julia; Frank, Johanna; Höllthaler, Josef; Schmid, Roland M; Huber, Wolfgang

2015-10-01

Cardiac output (CO) (liters per minute) is usually normalized (ie, indexed) to the patient's body surface area (BSA) resulting in the hemodynamic variable cardiac index (CI) (liters per minute per square meter). We aimed (1) to evaluate the impact of different body weight-based CO indexations on the resulting CI values and (2) to identify biometric parameters independently associated with CO in critically ill patients. The study is an analysis of a database containing transpulmonary thermodilution-derived hemodynamic variables of 234 medical intensive care unit patients. Cardiac index indexed to actual BSA was statistically significantly lower compared with CI indexed to predicted BSA in the totality of patients and in the subgroups of patients with body mass index greater than or equal to 25 kg/m(2) but less than 30 kg/m(2) and body mass index greater than or equal to 30 kg/m(2) (with a statistically significant difference in the proportion of low and high CI measurements). Multivariate analysis of the first CO measurement of each patient demonstrated that CO was independently associated with age (P biometric factors independently associated with CO. Age was identified as the most important factor with each year of age decreasing CO by 66 mL/min (95% confidence interval, 47-86 mL/min). The indexation of CO to BSA is highly dependent on the body weight estimation formula used to calculate BSA. Cardiac output is independently associated with the biometric factors age, height, and BWact. These factors might be considered for indexation of CO. Copyright © 2015 Elsevier Inc. All rights reserved.

On the Design of an Efficient Cardiac Health Monitoring System Through Combined Analysis of ECG and SCG Signals.

Science.gov (United States)

Sahoo, Prasan Kumar; Thakkar, Hiren Kumar; Lin, Wen-Yen; Chang, Po-Cheng; Lee, Ming-Yih

2018-01-28

Cardiovascular disease (CVD) is a major public concern and socioeconomic problem across the globe. The popular high-end cardiac health monitoring systems such as magnetic resonance imaging (MRI), computerized tomography scan (CT scan), and echocardiography (Echo) are highly expensive and do not support long-term continuous monitoring of patients without disrupting their activities of daily living (ADL). In this paper, the continuous and non-invasive cardiac health monitoring using unobtrusive sensors is explored aiming to provide a feasible and low-cost alternative to foresee possible cardiac anomalies in an early stage. It is learned that cardiac health monitoring based on sole usage of electrocardiogram (ECG) signals may not provide powerful insights as ECG provides shallow information on various cardiac activities in the form of electrical impulses only. Hence, a novel low-cost, non-invasive seismocardiogram (SCG) signal along with ECG signals are jointly investigated for the robust cardiac health monitoring. For this purpose, the in-laboratory data collection model is designed for simultaneous acquisition of ECG and SCG signals followed by mechanisms for the automatic delineation of relevant feature points in acquired ECG and SCG signals. In addition, separate feature points based novel approach is adopted to distinguish between normal and abnormal morphology in each ECG and SCG cardiac cycle. Finally, a combined analysis of ECG and SCG is carried out by designing a Naïve Bayes conditional probability model. Experiments on Institutional Review Board (IRB) approved licensed ECG/SCG signals acquired from real subjects containing 12,000 cardiac cycles show that the proposed feature point delineation mechanisms and abnormal morphology detection methods consistently perform well and give promising results. In addition, experimental results show that the combined analysis of ECG and SCG signals provide more reliable cardiac health monitoring compared to the

On the Design of an Efficient Cardiac Health Monitoring System Through Combined Analysis of ECG and SCG Signals

Directory of Open Access Journals (Sweden)

Prasan Kumar Sahoo

2018-01-01

Full Text Available Cardiovascular disease (CVD is a major public concern and socioeconomic problem across the globe. The popular high-end cardiac health monitoring systems such as magnetic resonance imaging (MRI, computerized tomography scan (CT scan, and echocardiography (Echo are highly expensive and do not support long-term continuous monitoring of patients without disrupting their activities of daily living (ADL. In this paper, the continuous and non-invasive cardiac health monitoring using unobtrusive sensors is explored aiming to provide a feasible and low-cost alternative to foresee possible cardiac anomalies in an early stage. It is learned that cardiac health monitoring based on sole usage of electrocardiogram (ECG signals may not provide powerful insights as ECG provides shallow information on various cardiac activities in the form of electrical impulses only. Hence, a novel low-cost, non-invasive seismocardiogram (SCG signal along with ECG signals are jointly investigated for the robust cardiac health monitoring. For this purpose, the in-laboratory data collection model is designed for simultaneous acquisition of ECG and SCG signals followed by mechanisms for the automatic delineation of relevant feature points in acquired ECG and SCG signals. In addition, separate feature points based novel approach is adopted to distinguish between normal and abnormal morphology in each ECG and SCG cardiac cycle. Finally, a combined analysis of ECG and SCG is carried out by designing a Naïve Bayes conditional probability model. Experiments on Institutional Review Board (IRB approved licensed ECG/SCG signals acquired from real subjects containing 12,000 cardiac cycles show that the proposed feature point delineation mechanisms and abnormal morphology detection methods consistently perform well and give promising results. In addition, experimental results show that the combined analysis of ECG and SCG signals provide more reliable cardiac health monitoring compared to

In vivo validation of cardiac output assessment in non-standard 3D echocardiographic images

Energy Technology Data Exchange (ETDEWEB)

Nillesen, M M; Lopata, R G P; Gerrits, I H; Thijssen, J M; De Korte, C L [Clinical Physics Laboratory-833, Department of Pediatrics, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); De Boode, W P [Neonatology, Department of Pediatrics, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Huisman, H J [Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Kapusta, L [Pediatric Cardiology, Department of Pediatrics, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)], E-mail: m.m.nillesen@cukz.umcn.nl

2009-04-07

Automatic segmentation of the endocardial surface in three-dimensional (3D) echocardiographic images is an important tool to assess left ventricular (LV) geometry and cardiac output (CO). The presence of speckle noise as well as the nonisotropic characteristics of the myocardium impose strong demands on the segmentation algorithm. In the analysis of normal heart geometries of standardized (apical) views, it is advantageous to incorporate a priori knowledge about the shape and appearance of the heart. In contrast, when analyzing abnormal heart geometries, for example in children with congenital malformations, this a priori knowledge about the shape and anatomy of the LV might induce erroneous segmentation results. This study describes a fully automated segmentation method for the analysis of non-standard echocardiographic images, without making strong assumptions on the shape and appearance of the heart. The method was validated in vivo in a piglet model. Real-time 3D echocardiographic image sequences of five piglets were acquired in radiofrequency (rf) format. These ECG-gated full volume images were acquired intra-operatively in a non-standard view. Cardiac blood flow was measured simultaneously by an ultrasound transit time flow probe positioned around the common pulmonary artery. Three-dimensional adaptive filtering using the characteristics of speckle was performed on the demodulated rf data to reduce the influence of speckle noise and to optimize the distinction between blood and myocardium. A gradient-based 3D deformable simplex mesh was then used to segment the endocardial surface. A gradient and a speed force were included as external forces of the model. To balance data fitting and mesh regularity, one fixed set of weighting parameters of internal, gradient and speed forces was used for all data sets. End-diastolic and end-systolic volumes were computed from the segmented endocardial surface. The cardiac output derived from this automatic segmentation was

In vivo validation of cardiac output assessment in non-standard 3D echocardiographic images

International Nuclear Information System (INIS)

Nillesen, M M; Lopata, R G P; Gerrits, I H; Thijssen, J M; De Korte, C L; De Boode, W P; Huisman, H J; Kapusta, L

2009-01-01

Automatic segmentation of the endocardial surface in three-dimensional (3D) echocardiographic images is an important tool to assess left ventricular (LV) geometry and cardiac output (CO). The presence of speckle noise as well as the nonisotropic characteristics of the myocardium impose strong demands on the segmentation algorithm. In the analysis of normal heart geometries of standardized (apical) views, it is advantageous to incorporate a priori knowledge about the shape and appearance of the heart. In contrast, when analyzing abnormal heart geometries, for example in children with congenital malformations, this a priori knowledge about the shape and anatomy of the LV might induce erroneous segmentation results. This study describes a fully automated segmentation method for the analysis of non-standard echocardiographic images, without making strong assumptions on the shape and appearance of the heart. The method was validated in vivo in a piglet model. Real-time 3D echocardiographic image sequences of five piglets were acquired in radiofrequency (rf) format. These ECG-gated full volume images were acquired intra-operatively in a non-standard view. Cardiac blood flow was measured simultaneously by an ultrasound transit time flow probe positioned around the common pulmonary artery. Three-dimensional adaptive filtering using the characteristics of speckle was performed on the demodulated rf data to reduce the influence of speckle noise and to optimize the distinction between blood and myocardium. A gradient-based 3D deformable simplex mesh was then used to segment the endocardial surface. A gradient and a speed force were included as external forces of the model. To balance data fitting and mesh regularity, one fixed set of weighting parameters of internal, gradient and speed forces was used for all data sets. End-diastolic and end-systolic volumes were computed from the segmented endocardial surface. The cardiac output derived from this automatic segmentation was

In vivo validation of cardiac output assessment in non-standard 3D echocardiographic images

Science.gov (United States)

Nillesen, M. M.; Lopata, R. G. P.; de Boode, W. P.; Gerrits, I. H.; Huisman, H. J.; Thijssen, J. M.; Kapusta, L.; de Korte, C. L.

2009-04-01

Automatic segmentation of the endocardial surface in three-dimensional (3D) echocardiographic images is an important tool to assess left ventricular (LV) geometry and cardiac output (CO). The presence of speckle noise as well as the nonisotropic characteristics of the myocardium impose strong demands on the segmentation algorithm. In the analysis of normal heart geometries of standardized (apical) views, it is advantageous to incorporate a priori knowledge about the shape and appearance of the heart. In contrast, when analyzing abnormal heart geometries, for example in children with congenital malformations, this a priori knowledge about the shape and anatomy of the LV might induce erroneous segmentation results. This study describes a fully automated segmentation method for the analysis of non-standard echocardiographic images, without making strong assumptions on the shape and appearance of the heart. The method was validated in vivo in a piglet model. Real-time 3D echocardiographic image sequences of five piglets were acquired in radiofrequency (rf) format. These ECG-gated full volume images were acquired intra-operatively in a non-standard view. Cardiac blood flow was measured simultaneously by an ultrasound transit time flow probe positioned around the common pulmonary artery. Three-dimensional adaptive filtering using the characteristics of speckle was performed on the demodulated rf data to reduce the influence of speckle noise and to optimize the distinction between blood and myocardium. A gradient-based 3D deformable simplex mesh was then used to segment the endocardial surface. A gradient and a speed force were included as external forces of the model. To balance data fitting and mesh regularity, one fixed set of weighting parameters of internal, gradient and speed forces was used for all data sets. End-diastolic and end-systolic volumes were computed from the segmented endocardial surface. The cardiac output derived from this automatic segmentation was

Cardiac output and regional blood flow following trauma

International Nuclear Information System (INIS)

Malik, A.B.; Loegering, D.J.; Saba, T.M.; Kaplan, J.E.

1978-01-01

The changes in cardiac output (2), regional blood blow (2r) and regional vascular resistance, and arterial pressure were studied in rats subjected to moderate (LD0) or severe (LD50) traumatic shock. 2 and 2r were determined using microspheres at 15, 60 and 180 min posttrauma. Arterial pressure decreased in both groups at 15 min and recovered by 3 h after sublethal (LD0) trauma, while arterial pressure did not return to control levels after LD50 trauma. 2 decreased in both groups at 15 min and returned to control only in the LD0 trauma group by 3 h. Cerebral, coronary, and hepatic arterial flows and resistances were maintained in both groups. Renal, intestinal, and splenic flows decreased and resistances were maintained in both groups. Renal, intestinal, and splenic flows decreased and resistances increased in both groups by 15 min and returned to control levels by 3 h only in the LD0 trauma group. Total hepatic and hepatic portal flows decreased at 60 min and returned to control levels at 3 h after LD0 trauma, while there was significant depression in these parameters 3 h after LD50 trauma. Therefore, sublethal and severe trauma resulted in early redistribution of flow favoring the coronary, cerebral, and hepatic arterial beds. However, renal, intestinal, splenic, and portal flows remained depressed only in severely traumatized rats, suggesting that continued hypofusion is a factor in the multiple organ failure and death following severe traumatic injury

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.

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.

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

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

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...

Cardiodynamicsgram: a novel tool for monitoring cardiac function in exercise training.

Science.gov (United States)

Wen, Xu; Guo, Bokai; Gong, Yinglan; Xia, Ling; Yu, Jie

2018-04-27

This study evaluated the feasibility of cardiodynamicsgram (CDG) for monitoring the cardiac functions of athletes and exercisers. CDG could provide an effective, simple, and economical tool for exercise training. Seventeen middle-distance race athletes aged 14-28 years old were recruited. CDG tests and blood test including creatine kinase (CK), CK-MB isoenzyme, and high-sensitivity troponin I (hsTnI) were performed before a high-intensity prolonged training, as well as 2 and 14 h after training, respectively. The CDG test result was unsatisfactory when the CK test result was used as standard. However, the accuracy of CDG test was about 80% when CK-MB and hsTnI were used as standards. Thus, CDG offers a noninvasive, simple, and economical approach for monitoring the cardiac function of athletes and exercisers during exercise training. Nonetheless, the applicability of CDG needs further investigation.

Advanced hemodynamic monitoring in intensive care medicine : A German web-based survey study.

Science.gov (United States)

Saugel, B; Reese, P C; Wagner, J Y; Buerke, M; Huber, W; Kluge, S; Prondzinsky, R

2018-04-01

Advanced hemodynamic monitoring is recommended in patients with complex circulatory shock. To evaluate the current attitudes and beliefs among German intensivists, regarding advanced hemodynamic monitoring, the actual hemodynamic management in clinical practice, and the barriers to using it. Web-based survey among members of the German Society of Medical Intensive Care and Emergency Medicine. Of 284 respondents, 249 (87%) agreed that further hemodynamic assessment is needed to determine the type of circulatory shock if no clear clinical diagnosis can be made. In all, 281 (99%) agreed that echocardiography is helpful for this purpose (transpulmonary thermodilution: 225 [79%]; pulmonary artery catheterization: 126 [45%]). More than 70% of respondents agreed that blood flow variables (cardiac output, stroke volume) should be measured in patients with hemodynamic instability. The parameters most respondents agreed should be assessed in a patient with hemodynamic instability were mean arterial pressure, cardiac output, and serum lactate. Echocardiography is available in 99% of ICUs (transpulmonary thermodilution: 91%; pulmonary artery catheter: 63%). The respondents stated that, in clinical practice, invasive arterial pressure measurements and serum lactate measurements are performed in more than 90% of patients with hemodynamic instability (cardiac output monitoring in about 50%; transpulmonary thermodilution in about 40%). The respondents did not feel strong barriers to the use of advanced hemodynamic monitoring in clinical practice. This survey study shows that German intensivists deem advanced hemodynamic assessment necessary for the differential diagnosis of circulatory shock and to guide therapy with fluids, vasopressors, and inotropes in ICU patients.

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

False alarm reduction in BSN-based cardiac monitoring using signal quality and activity type information.

Science.gov (United States)

Tanantong, Tanatorn; Nantajeewarawat, Ekawit; Thiemjarus, Surapa

2015-02-09

False alarms in cardiac monitoring affect the quality of medical care, impacting on both patients and healthcare providers. In continuous cardiac monitoring using wireless Body Sensor Networks (BSNs), the quality of ECG signals can be deteriorated owing to several factors, e.g., noises, low battery power, and network transmission problems, often resulting in high false alarm rates. In addition, body movements occurring from activities of daily living (ADLs) can also create false alarms. This paper presents a two-phase framework for false arrhythmia alarm reduction in continuous cardiac monitoring, using signals from an ECG sensor and a 3D accelerometer. In the first phase, classification models constructed using machine learning algorithms are used for labeling input signals. ECG signals are labeled with heartbeat types and signal quality levels, while 3D acceleration signals are labeled with ADL types. In the second phase, a rule-based expert system is used for combining classification results in order to determine whether arrhythmia alarms should be accepted or suppressed. The proposed framework was validated on datasets acquired using BSNs and the MIT-BIH arrhythmia database. For the BSN dataset, acceleration and ECG signals were collected from 10 young and 10 elderly subjects while they were performing ADLs. The framework reduced the false alarm rate from 9.58% to 1.43% in our experimental study, showing that it can potentially assist physicians in diagnosing a vast amount of data acquired from wireless sensors and enhance the performance of continuous cardiac monitoring.

Correction of time resolution of an ambulatory cardiac monitor (VEST)

International Nuclear Information System (INIS)

Kumita, Shin-ichiro; Nishimura, Tsunehiko; Hayashida, Kohei; Uehara, Toshiisa

1990-01-01

Using ambulatory cardiac monitor (VEST) at exercise study, its time resolution is very important factor. We evaluated the time resolution of VEST using pulsate cardiac baloon phantom. Four analysis were carried out; no smoothing (NS) method, 3 points smoothing (3S) method, short sampling interval (SS) method, and digital filter (DF) method. By comparison of |ΔEF| (|EF:HR120-EF: HR60|) among 4 analysis methods, |ΔEF| by DF method was significant small (NS:3.58±3.01, 3S: 4.46±0.95, SS: 3.35±3.26, DF: 1.11±1.28%). We conclude that correction of time resolution by digital filter is necessary when we use VEST during exercise. (author)

Engineered hybrid cardiac patches with multifunctional electronics for online monitoring and regulation of tissue function

Science.gov (United States)

Feiner, Ron; Engel, Leeya; Fleischer, Sharon; Malki, Maayan; Gal, Idan; Shapira, Assaf; Shacham-Diamand, Yosi; Dvir, Tal

2016-06-01

In cardiac tissue engineering approaches to treat myocardial infarction, cardiac cells are seeded within three-dimensional porous scaffolds to create functional cardiac patches. However, current cardiac patches do not allow for online monitoring and reporting of engineered-tissue performance, and do not interfere to deliver signals for patch activation or to enable its integration with the host. Here, we report an engineered cardiac patch that integrates cardiac cells with flexible, freestanding electronics and a 3D nanocomposite scaffold. The patch exhibited robust electronic properties, enabling the recording of cellular electrical activities and the on-demand provision of electrical stimulation for synchronizing cell contraction. We also show that electroactive polymers containing biological factors can be deposited on designated electrodes to release drugs in the patch microenvironment on demand. We expect that the integration of complex electronics within cardiac patches will eventually provide therapeutic control and regulation of cardiac function.

Engineered hybrid cardiac patches with multifunctional electronics for online monitoring and regulation of tissue function

Science.gov (United States)

Feiner, Ron; Engel, Leeya; Fleischer, Sharon; Malki, Maayan; Gal, Idan; Shapira, Assaf; Shacham-Diamand, Yosi; Dvir, Tal

2016-01-01

In cardiac tissue engineering approaches to treat myocardial infarction, cardiac cells are seeded within three-dimensional porous scaffolds to create functional cardiac patches. However, current cardiac patches do not allow for online monitoring and reporting of engineered-tissue performance, and do not interfere to deliver signals for patch activation or to enable its integration with the host. Here, we report an engineered cardiac patch that integrates cardiac cells with flexible, free-standing electronics and a 3D nanocomposite scaffold. The patch exhibited robust electronic properties, enabling the recording of cellular electrical activities and the on-demand provision of electrical stimulation for synchronizing cell contraction. We also show that electroactive polymers containing biological factors can be deposited on designated electrodes to release drugs in the patch microenvironment on-demand. We expect that the integration of complex electronics within cardiac patches will eventually provide therapeutic control and regulation of cardiac function. PMID:26974408

The Evolution and Application of Cardiac Monitoring for Occult Atrial Fibrillation in Cryptogenic Stroke and TIA.

Science.gov (United States)

Miller, Daniel J; Shah, Kavit; Modi, Sumul; Mahajan, Abhimanyu; Zahoor, Salman; Affan, Muhammad

2016-04-01

The evaluation of the stroke and transient ischemic attack (TIA) patient has been historically predominated by the initial evaluation in the hospital setting. As the etiology of stroke has eluded us in approximately one third of all acute events, the medical community has been eager to seek the answer to this mystery. In recent years, we have seen an explosion of innovations and trends allowing for a more detailed post stroke assessment strategy aimed at the identification of occult atrial fibrillation as the etiologic cause for the cryptogenic event. This has been achieved through the evolution and aggressive application and study of prolonged and advanced cardiac monitoring. This review is aimed to clarify and elucidate the standard and novel cardiac monitoring methods that have become available for use by the medical community and expected in the higher level care of cryptogenic stroke and TIA patients. These cardiac monitoring methods and devices are as heterogeneous as our patient population and have their own advantages and disadvantages. Many factors may be taken into consideration in choosing the appropriate cardiac monitoring method and are highlighted for consideration in this review. With a judicious approach to investigating the cryptogenic stroke population, and applying a wealth of novel treatment options, we may move forward into a new era of stroke prevention.

False Alarm Reduction in BSN-Based Cardiac Monitoring Using Signal Quality and Activity Type Information

Directory of Open Access Journals (Sweden)

Tanatorn Tanantong

2015-02-01

Full Text Available False alarms in cardiac monitoring affect the quality of medical care, impacting on both patients and healthcare providers. In continuous cardiac monitoring using wireless Body Sensor Networks (BSNs, the quality of ECG signals can be deteriorated owing to several factors, e.g., noises, low battery power, and network transmission problems, often resulting in high false alarm rates. In addition, body movements occurring from activities of daily living (ADLs can also create false alarms. This paper presents a two-phase framework for false arrhythmia alarm reduction in continuous cardiac monitoring, using signals from an ECG sensor and a 3D accelerometer. In the first phase, classification models constructed using machine learning algorithms are used for labeling input signals. ECG signals are labeled with heartbeat types and signal quality levels, while 3D acceleration signals are labeled with ADL types. In the second phase, a rule-based expert system is used for combining classification results in order to determine whether arrhythmia alarms should be accepted or suppressed. The proposed framework was validated on datasets acquired using BSNs and the MIT-BIH arrhythmia database. For the BSN dataset, acceleration and ECG signals were collected from 10 young and 10 elderly subjects while they were performing ADLs. The framework reduced the false alarm rate from 9.58% to 1.43% in our experimental study, showing that it can potentially assist physicians in diagnosing a vast amount of data acquired from wireless sensors and enhance the performance of continuous cardiac monitoring.

Prolonged Cardiac Monitoring to Detect Atrial Fibrillation after Cryptogenic Stroke or Transient Ischemic Attack: A Meta-Analysis of Randomized Controlled Trials.

Science.gov (United States)

Dahal, Khagendra; Chapagain, Bikas; Maharjan, Raju; Farah, Hussam W; Nazeer, Ayesha; Lootens, Robert J; Rosenfeld, Alan

2016-07-01

The cause of ischemic stroke or transient ischemic attack (TIA) remains unclear after initial cardiac monitoring in approximately one-third of patients. Randomized controlled trials (RCTs) showed that the prolonged cardiac monitoring of patients with cryptogenic stroke or TIA increased detection of atrial fibrillation (AF). We aimed to perform a meta-analysis of all RCTs that evaluated the prolonged monitoring ≥7 days in patients with cryptogenic stroke or TIA. We searched PubMed, EMBASE, Cochrane CENTRAL, and relevant references for RCTs without language restriction (inception through December 2014) and performed meta-analysis using random effects model. Detection of AF, use of anticoagulation at follow-up, recurrent stroke or TIA, and mortality were major outcomes. Four RCTs with 1149 total patients were included in the meta-analysis. Prolonged cardiac monitoring ≥7 days compared to shorter cardiac monitoring of ≤48 hours duration increased the detection of AF (≥30 seconds duration) in patients after cryptogenic stroke or TIA (13.8% vs. 2.5%; odds ratio [OR], 6.4; 95% confidence interval [CI], 3.50-11.73; P vs. 5.2%; 5.68[3.3-9.77]; P stroke or TIA (0.78[0.40-1.55]; P = 0.48; I(2) , 0%) and mortality (1.33[0.29-6.00]; P = 0.71; I(2) , 0%] were observed between two strategies. Prolonged cardiac monitoring improves detection of atrial fibrillation and anti-coagulation use after cryptogenic stroke or TIA and therefore should be considered instead of shorter duration of cardiac monitoring. © 2015 Wiley Periodicals, Inc.

Preferential cephalic redistribution of left ventricular cardiac output during therapeutic hypothermia for perinatal hypoxic-ischemic encephalopathy.

Science.gov (United States)

Hochwald, Ori; Jabr, Mohammad; Osiovich, Horacio; Miller, Steven P; McNamara, Patrick J; Lavoie, Pascal M

2014-05-01

To determine the relationship between left ventricular cardiac output (LVCO), superior vena cava (SVC) flow, and brain injury during whole-body therapeutic hypothermia. Sixteen newborns with moderate or severe hypoxic-ischemic encephalopathy were studied using echocardiography during and immediately after therapeutic hypothermia. Measures were also compared with 12 healthy newborns of similar postnatal age. Newborns undergoing therapeutic hypothermia also had cerebral magnetic resonance imaging as part of routine clinical care on postnatal day 3-4. LVCO was markedly reduced (mean ± SD 126 ± 38 mL/kg/min) during therapeutic hypothermia, whereas SVC flow was maintained within expected normal values (88 ± 27 mL/kg/min) such that SVC flow represented 70% of the LVCO. The reduction in LVCO during therapeutic hypothermia was mainly accounted by a reduction in heart rate (99 ± 13 vs 123 ± 17 beats/min; P newborns without brain injury (P = .013). Newborns with perinatal hypoxic-ischemic encephalopathy showed a preferential systemic-to-cerebral redistribution of cardiac blood flow during whole-body therapeutic hypothermia, which may reflect a lack of cerebral vascular adaptation in newborns with more severe brain injury. Copyright © 2014 Elsevier Inc. All rights reserved.

Clinical review: Update on hemodynamic monitoring - a consensus of 16.

NARCIS (Netherlands)

Vincent, J.L.; Rhodes, A.; Perel, A.; Martin, G.S.; Rocca, G.D.; Vallet, B.; Pinsky, M.R.; Hofer, C.K.; Teboul, J.L.; Boode, W.P. de; Scolletta, S.; Viellard-Baron, A.; Backer, D. de; Walley, K.R.; Maggiorini, M.; Singer, M.

2011-01-01

Hemodynamic monitoring plays a fundamental role in the management of acutely ill patients. With increased concerns about the use of invasive techniques, notably the pulmonary artery catheter, to measure cardiac output, recent years have seen an influx of new, less-invasive means of measuring

Engineered hybrid cardiac patches with multifunctional electronics for online monitoring and regulation of tissue function.

Science.gov (United States)

Feiner, Ron; Engel, Leeya; Fleischer, Sharon; Malki, Maayan; Gal, Idan; Shapira, Assaf; Shacham-Diamand, Yosi; Dvir, Tal

2016-06-01

In cardiac tissue engineering approaches to treat myocardial infarction, cardiac cells are seeded within three-dimensional porous scaffolds to create functional cardiac patches. However, current cardiac patches do not allow for online monitoring and reporting of engineered-tissue performance, and do not interfere to deliver signals for patch activation or to enable its integration with the host. Here, we report an engineered cardiac patch that integrates cardiac cells with flexible, freestanding electronics and a 3D nanocomposite scaffold. The patch exhibited robust electronic properties, enabling the recording of cellular electrical activities and the on-demand provision of electrical stimulation for synchronizing cell contraction. We also show that electroactive polymers containing biological factors can be deposited on designated electrodes to release drugs in the patch microenvironment on demand. We expect that the integration of complex electronics within cardiac patches will eventually provide therapeutic control and regulation of cardiac function.

Pulmonary diffusing capacity, capillary blood volume, and cardiac output during sustained microgravity

Science.gov (United States)

Prisk, G. K.; Guy, Harold J. B.; Elliott, Ann R.; Deutschman, Robert A., III; West, John B.

1993-01-01

We measured pulmonary diffusing capacity (DL), diffusing capacity per unit lung volume, pulmonary capillary blood volume (Vc), membrane diffusing capacity (Dm), pulmonary capillary blood flow or cardiac output (Qc), and cardiac stroke volume (SV) in four subjects exposed to nine days of microgravity. DL in microgravity was elevated compared with preflight standing values and was higher than preflight supine because of the elevation of both Vc and Dm. The elevation in Vc was comparable to that measured supine in 1 G, but the increase in Dm was in sharp contrast to the supine value. We postulate that, in 0 G, pulmonary capillary blood is evenly distributed throughout the lung, providing for uniform capillary filling, leading to an increase in the surface area available for diffusion. By contrast, in the supine 1-G state, the capillaries are less evenly filled, and although a similar increase in blood volume is observed, the corresponding increase in surface area does not occur. DL and its subdivisions showed no adaptive changes from the first measurement 24 h after the start of 0 G to eight days later. Similarly, there were no trends in the postflight data, suggesting that the principal mechanism of these changes was gravitational. The increase in Dm suggests that subclinical pulmonary edema did not result from exposure to 0 G. Qc was modestly increased inflight and decreased postflight compared with preflight standing. Compared with preflight standing, SV was increased 46 percent inflight and decreased 14 percent in the 1st week postflight. There were temporal changes in Qc and SV during 0 G, with the highest values recorded at the first measurement, 24 h into the flight. The lowest values of Qc and SV occurred on the day of return.

The novel application of Benford's second order analysis for monitoring radiation output in interventional radiology.

Science.gov (United States)

Cournane, S; Sheehy, N; Cooke, J

2014-06-01

Benford's law is an empirical observation which predicts the expected frequency of digits in naturally occurring datasets spanning multiple orders of magnitude, with the law having been most successfully applied as an audit tool in accountancy. This study investigated the sensitivity of the technique in identifying system output changes using simulated changes in interventional radiology Dose-Area-Product (DAP) data, with any deviations from Benford's distribution identified using z-statistics. The radiation output for interventional radiology X-ray equipment is monitored annually during quality control testing; however, for a considerable portion of the year an increased output of the system, potentially caused by engineering adjustments or spontaneous system faults may go unnoticed, leading to a potential increase in the radiation dose to patients. In normal operation recorded examination radiation outputs vary over multiple orders of magnitude rendering the application of normal statistics ineffective for detecting systematic changes in the output. In this work, the annual DAP datasets complied with Benford's first order law for first, second and combinations of the first and second digits. Further, a continuous 'rolling' second order technique was devised for trending simulated changes over shorter timescales. This distribution analysis, the first employment of the method for radiation output trending, detected significant changes simulated on the original data, proving the technique useful in this case. The potential is demonstrated for implementation of this novel analysis for monitoring and identifying change in suitable datasets for the purpose of system process control. Copyright © 2013 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Diagnostic Yield of Extended Cardiac Patch Monitoring in Patients with Stroke or TIA

Directory of Open Access Journals (Sweden)

Christie E Tung

2015-01-01

Full Text Available Background: It is important to evaluate patients with TIA or stroke for atrial fibrillation (AF because the detection of AF changes the recommended anti-thrombotic regimen from treatment with an antiplatelet agent to oral anticoagulation. This study describes the diagnostic yield of a patch-based, single-use, and water-resistant 14-day continuous cardiac rhythm monitor (ZIO Patch in patients with stroke or TIA.Methods: We obtained data from the manufacturer and servicer of the ZIO Patch (iRhythm Technologies. Patients who were monitored between January 2012 and June 2013 and whose indication for monitoring was TIA or stroke were included. The duration of monitoring, the number and type of arrhythmias, and the time to first arrhythmia were documented. Results: 1,171 monitoring reports were analyzed. The mean monitor wear time was 10.9 days and the median wear time was 13.0 days (interquartile range 7.2-14.0. The median analyzable time relative to the total wear time was 98.7% (IQR 96.0-99.5%. AF was present in 5.0% of all reports. The mean duration before the first episode of paroxysmal AF (PAF was 1.5 days and the median duration was 0.4 days. 14.3% of first PAF episodes occurred after 48 hours. The mean PAF burden was 12.7% of the total monitoring duration. Conclusion: Excellent quality of the recordings and very good patient compliance coupled with a substantial proportion of AF detection beyond the first 48 hours of monitoring suggest that the cardiac patch is superior to conventional 48-hour Holter monitors for AF detection in patients with stroke or TIA.

Diagnostic Yield of Extended Cardiac Patch Monitoring in Patients with Stroke or TIA.

Science.gov (United States)

Tung, Christie E; Su, Derek; Turakhia, Mintu P; Lansberg, Maarten G

2014-01-01

It is important to evaluate patients with transient ischemic attack (TIA) or stroke for atrial fibrillation (AF) because the detection of AF changes the recommended anti-thrombotic regimen from treatment with an antiplatelet agent to oral anticoagulation. This study describes the diagnostic yield of a patch-based, single-use, and water-resistant 14-day continuous cardiac rhythm monitor (ZIO Patch) in patients with stroke or TIA. We obtained data from the manufacturer and servicer of the ZIO Patch (iRhythm Technologies). Patients who were monitored between January 2012 and June 2013 and whose indication for monitoring was TIA or stroke were included. The duration of monitoring, the number and type of arrhythmias, and the time to first arrhythmia were documented. One thousand one hundred seventy-one monitoring reports were analyzed. The mean monitor wear time was 10.9 days and the median wear time was 13.0 days (interquartile range 7.2-14.0). The median analyzable time relative to the total wear time was 98.7% (IQR 96.0-99.5%). AF was present in 5.0% of all reports. The mean duration before the first episode of paroxysmal AF (PAF) was 1.5 days and the median duration was 0.4 days. 14.3% of first PAF episodes occurred after 48 h. The mean PAF burden was 12.7% of the total monitoring duration. Excellent quality of the recordings and very good patient compliance coupled with a substantial proportion of AF detection beyond the first 48 h of monitoring suggest that the cardiac patch is superior to conventional 48-h Holter monitors for AF detection in patients with stroke or TIA.

Pilot Study: Estimation of Stroke Volume and Cardiac Output from Pulse Wave Velocity.

Directory of Open Access Journals (Sweden)

Yurie Obata

Full Text Available Transesophageal echocardiography (TEE is increasingly replacing thermodilution pulmonary artery catheters to assess hemodynamics in patients at high risk for cardiovascular morbidity. However, one of the drawbacks of TEE compared to pulmonary artery catheters is the inability to measure real time stroke volume (SV and cardiac output (CO continuously. The aim of the present proof of concept study was to validate a novel method of SV estimation, based on pulse wave velocity (PWV in patients undergoing cardiac surgery.This is a retrospective observational study. We measured pulse transit time by superimposing the radial arterial waveform onto the continuous wave Doppler waveform of the left ventricular outflow tract, and calculated SV (SVPWV using the transformed Bramwell-Hill equation. The SV measured by TEE (SVTEE was used as a reference.A total of 190 paired SV were measured from 28 patients. A strong correlation was observed between SVPWV and SVTEE with the coefficient of determination (R2 of 0.71. A mean difference between the two (bias was 3.70 ml with the limits of agreement ranging from -20.33 to 27.73 ml and a percentage error of 27.4% based on a Bland-Altman analysis. The concordance rate of two methods was 85.0% based on a four-quadrant plot. The angular concordance rate was 85.9% with radial limits of agreement (the radial sector that contained 95% of the data points of ± 41.5 degrees based on a polar plot.PWV based SV estimation yields reasonable agreement with SV measured by TEE. Further studies are required to assess its utility in different clinical situations.

An Interoperable System toward Cardiac Risk Stratification from ECG Monitoring

Directory of Open Access Journals (Sweden)

Cristina Soguero-Ruiz

2018-03-01

Full Text Available Many indices have been proposed for cardiovascular risk stratification from electrocardiogram signal processing, still with limited use in clinical practice. We created a system integrating the clinical definition of cardiac risk subdomains from ECGs and the use of diverse signal processing techniques. Three subdomains were defined from the joint analysis of the technical and clinical viewpoints. One subdomain was devoted to demographic and clinical data. The other two subdomains were intended to obtain widely defined risk indices from ECG monitoring: a simple-domain (heart rate turbulence (HRT, and a complex-domain (heart rate variability (HRV. Data provided by the three subdomains allowed for the generation of alerts with different intensity and nature, as well as for the grouping and scrutinization of patients according to the established processing and risk-thresholding criteria. The implemented system was tested by connecting data from real-world in-hospital electronic health records and ECG monitoring by considering standards for syntactic (HL7 messages and semantic interoperability (archetypes based on CEN/ISO EN13606 and SNOMED-CT. The system was able to provide risk indices and to generate alerts in the health records to support decision-making. Overall, the system allows for the agile interaction of research and clinical practice in the Holter-ECG-based cardiac risk domain.

An Interoperable System toward Cardiac Risk Stratification from ECG Monitoring

Science.gov (United States)

Mora-Jiménez, Inmaculada; Ramos-López, Javier; Quintanilla Fernández, Teresa; García-García, Antonio; Díez-Mazuela, Daniel; García-Alberola, Arcadi

2018-01-01

Many indices have been proposed for cardiovascular risk stratification from electrocardiogram signal processing, still with limited use in clinical practice. We created a system integrating the clinical definition of cardiac risk subdomains from ECGs and the use of diverse signal processing techniques. Three subdomains were defined from the joint analysis of the technical and clinical viewpoints. One subdomain was devoted to demographic and clinical data. The other two subdomains were intended to obtain widely defined risk indices from ECG monitoring: a simple-domain (heart rate turbulence (HRT)), and a complex-domain (heart rate variability (HRV)). Data provided by the three subdomains allowed for the generation of alerts with different intensity and nature, as well as for the grouping and scrutinization of patients according to the established processing and risk-thresholding criteria. The implemented system was tested by connecting data from real-world in-hospital electronic health records and ECG monitoring by considering standards for syntactic (HL7 messages) and semantic interoperability (archetypes based on CEN/ISO EN13606 and SNOMED-CT). The system was able to provide risk indices and to generate alerts in the health records to support decision-making. Overall, the system allows for the agile interaction of research and clinical practice in the Holter-ECG-based cardiac risk domain. PMID:29494497

Clinical experience in extended cardiac monitoring with the SEEQ™ satellite wireless system

Directory of Open Access Journals (Sweden)

Diego Vanegas-Cadavid

2018-05-01

Full Text Available Objectives: To present the clinical experience with a new extended (for 15 days, wireless, and satellite cardiac monitoring system in a group of patients with suspicion of cardiac arrhythmia. Method: The study included a cohort of 100 patients seen in the Cardiovascular Electrophysiology Unit of a reference hospital. They were suspected of having a cardiac arrhythmia, with no electrocardiographic diagnosis of the cause, despite previous examinations. They were subjected to SEEQ-type (Medtronic external cardiac monitoring for 15 days, with the outcomes recorded. Results: Of the total of 100 subjects studied, 51% were male, and the median age was 60 years (range: 5 - 91 years. The main symptoms were palpitation, and the most prevalent comorbidity was arterial hypertension (47%. Almost all (98% of them had a previous Holter study, and 46% had two studies, which were inconclusive in explaining the symptoms. The SEEQ monitoring recorded a significant electrocardiographic abnormality in 22% of the patients. A pacemaker implant was the treatment most applied and atrial fibrillation was the most frequent arrhythmia in 50% of the positive findings. There was a higher and significant percentage of positive diagnoses in males. Conclusions: External, satellite, wireless cardiac monitoring extended for 15 days, is a novel tool that can increase the probability of documenting a clinically significant electrocardiographic abnormality in those patients who suffer recurrent cardiovascular symptoms. Resumen: Objetivos: Dar a conocer la experiencia clínica con un nuevo sistema de monitorización cardiaca extendida (por 15 días, inalámbrica y satelital en un grupo de pacientes con sospecha de arritmias cardíacas. Metodología: Cohorte de 100 pacientes atendidos en la unidad de Electrofisiología cardiovascular de un centro de referencia, con sospecha de arritmia cardíaca, sin diagnóstico electrocardiográfico causal, a pesar de exámenes previos. Se les aplic

Remote monitoring of implantable cardiac devices: current state and future directions.

Science.gov (United States)

Ganeshan, Raj; Enriquez, Alan D; Freeman, James V

2018-01-01

Recent evidence has demonstrated substantial benefits associated with remote monitoring of cardiac implantable electronic devices (CIEDs), and treatment guidelines have endorsed the use of remote monitoring. Familiarity with the features of remote monitoring systems and the data supporting its use are vital for physicians' care for patients with CEIDs. Remote monitoring remains underutilized, but its use is expanding including in new practice settings including emergency departments. Patient experience and outcomes are positive, with earlier detection of clinical events such as atrial fibrillation, reductions in inappropriate implantable cardioverter-defibrillator (ICD) shocks and potentially a decrease in mortality with frequent remote monitoring utilizaiton. Rates of hospitalization are reduced among remote monitoring users, and the replacement of outpatient follow-up visits with remote monitoring transmissions has been shown to be well tolerated. In addition, health resource utilization is lower and remote monitoring has been associated with considerable cost savings. A dose relationship exists between use of remote monitoring and patient outcomes, and those with early and high transmission rates have superior outcomes. Remote monitoring provides clinicians with the ability to provide comprehensive follow-up care for patients with CIEDs. Patient outcomes are improved, and resource utilization is decreased with appropriate use of remote monitoring. Future efforts must focus on improving the utilization and efficiency of remote monitoring.

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.

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

Relationship between cardiac function and resting cerebral blood flow

DEFF Research Database (Denmark)

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

2014-01-01

) 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...

System for the diagnosis and monitoring of coronary artery disease, acute coronary syndromes, cardiomyopathy and other cardiac conditions

Science.gov (United States)

Schlegel, Todd T. (Inventor); Arenare, Brian (Inventor)

2008-01-01

Cardiac electrical data are received from a patient, manipulated to determine various useful aspects of the ECG signal, and displayed and stored in a useful form using a computer. The computer monitor displays various useful information, and in particular graphically displays various permutations of reduced amplitude zones and kurtosis that increase the rapidity and accuracy of cardiac diagnoses. New criteria for reduced amplitude zones are defined that enhance the sensitivity and specificity for detecting cardiac abnormalities.

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

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...

Monitor de eventos electrocardiacos implementado en plataforma PDA Monitor of cardiac events implemented in PDA platform

Directory of Open Access Journals (Sweden)

John Bustamante

Full Text Available El monitoreo ambulatorio de eventos electrocardiacos es una herramienta valiosa en el diagnóstico de arritmias cardiacas, involucradas en procesos patológicos como miocardiopatías, estadios post-infarto, lesiones del sistema autónomo cardiaco, etc.; infortunadamente aún no es posible su uso extensivo debido a los altos costos que implica la adquisición de estos equipos. Con este propósito, se diseña y desarrolla mediante el uso de asistentes digitales personales, un monitor de eventos cardiacos con capacidad de grabación pre-sintomática y post-sintomática, visualización de señal electrocardiográfica en tiempo real, grabación automática de bradicardias y taquicardias, y posibilidad de anotación de síntomas por parte del paciente. Para ello se desarrolló un componente de hardware para la adquisición y tratamiento de las señales, un software para el monitoreo en plataforma Palm OS® y una aplicación para la descarga y análisis de los datos almacenados. Las validaciones del prototipo se realizaron mediante un simulador electrocardiográfico, un simulador de arritmias basado en registros de la base de datos de arritmias del Massachusetts Institute of Technology y Beth Israel Hospital, y pruebas piloto con personas sanas y pacientes con arritmias. En este reporte preliminar se enseña cómo el prototipo desarrollado, constituye una alternativa viable para el monitoreo ambulatorio de arritmias aprovechando las capacidades de almacenamiento, procesamiento y visualización con que cuentan los asistentes digitales actuales, con la ventaja adicional de que su uso no está restringido a una sola utilidad y su accesibilidad económica se facilita debido a su amplia disponibilidad comercial.Ambulatory monitoring of electro-cardiac events constitutes a valuable tool in the diagnosis of cardiac arrhythmias involved in pathologic processes such as myocardiopathies, post-infarction stages, autonomous cardiac system injuries, etc

Design of a cardiac monitor in terms of parameters of QRS complex.

Science.gov (United States)

Chen, Zhen-cheng; Ni, Li-li; Su, Ke-ping; Wang, Hong-yan; Jiang, Da-zong

2002-08-01

Objective. To design a portable cardiac monitor system based on the available ordinary ECG machine and works on the basis of QRS parameters. Method. The 80196 single chip microcomputer was used as the central microprocessor and real time electrocardiac signal was collected and analyzed [correction of analysized] in the system. Result. Apart from the performance of an ordinary monitor, this machine possesses also the following functions: arrhythmia analysis, HRV analysis, alarm, freeze, and record of automatic papering. Convenient in carrying, the system is powered by AC or DC sources. Stability, low power and low cost are emphasized in the hardware design; and modularization method is applied in software design. Conclusion. Popular in usage and low cost made the portable monitor system suitable for use under simple conditions.

Enabling social listening for cardiac safety monitoring: Proceedings from a drug information association-cardiac safety research consortium cosponsored think tank.

Science.gov (United States)

Seifert, Harry A; Malik, Raleigh E; Bhattacharya, Mondira; Campbell, Kevin R; Okun, Sally; Pierce, Carrie; Terkowitz, Jeffrey; Turner, J Rick; Krucoff, Mitchell W; Powell, Gregory E

2017-12-01

This white paper provides a summary of the presentations and discussions from a think tank on "Enabling Social Listening for Cardiac Safety Monitoring" trials that was cosponsored by the Drug Information Association and the Cardiac Safety Research Consortium, and held at the White Oak headquarters of the US Food and Drug Administration on June 3, 2016. The meeting's goals were to explore current methods of collecting and evaluating social listening data and to consider their applicability to cardiac safety surveillance. Social listening is defined as the act of monitoring public postings on the Internet. It has several theoretical advantages for drug and device safety. First, these include the ability to detect adverse events that are "missed" by traditional sources and the ability to detect adverse events sooner than would be allowed by traditional sources, both by affording near-real-time access to data from culturally and geographically diverse sources. Social listening can also potentially introduce a novel patient voice into the conversation about drug safety, which could uniquely augment understanding of real-world medication use obtained from more traditional methodologies. Finally, it can allow for access to information about drug misuse and diversion. To date, the latter 2 of these have been realized. Although regulators from the Food and Drug Administration and the United Kingdom's Medicines and Healthcare Products Regulatory Agency participated in the think tank along with representatives from industry, academia, and patient groups, this article should not be construed to constitute regulatory guidance. Copyright © 2017 Elsevier Inc. All rights reserved.

Current and Emerging Uses of Insertable Cardiac Monitors: Evaluation of Syncope and Monitoring for Atrial Fibrillation.

Science.gov (United States)

Tomson, Todd T; Passman, Rod

Insertable cardiac monitors (ICMs) have provided clinicians with a superb tool for assessing infrequent or potentially asymptomatic arrhythmias. ICMs have shown their usefulness in the evaluation of unexplained syncope, providing high diagnostic yields in a cost-effective manner. While unexplained syncope continues to be the most common reason for their use, ICMs are increasingly being used for the monitoring of atrial fibrillation (AF). Recent trials have demonstrated that a substantial proportion of patients with cryptogenic stroke have AF detected only by the prolonged monitoring provided by ICMs. A particularly promising and emerging use for ICMs is in the management of anticoagulation in patients with known paroxysmal AF. The introduction in recent years of ICMs with automatic AF detection algorithms and continuous remote monitoring in combination with novel oral anticoagulants have opened the door for targeted anticoagulation guided by remote monitoring, a strategy that has recently shown promise in pilot studies of this technique. While further research is needed before official recommendations can be given, this use of ICMs opens exciting new possibilities for personalized medicine that could potentially reduce bleeding risk and improve quality of life in patients with atrial fibrillation.

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

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.

Electrical velocimetry for non-invasive monitoring of the closure of the ductus arteriosus in preterm infants.

Science.gov (United States)

Rodríguez Sánchez de la Blanca, Ana; Sánchez Luna, M; González Pacheco, N; Arriaga Redondo, M; Navarro Patiño, N

2018-02-01

Closure of a patent ductus arteriosus (PDA) in preterm infants modifies cardiac output and induces adaptive changes in the hemodynamic situation. The present study aims to analyze those changes, through a non-invasive cardiac output monitor based on blood electrical velocimetry, in preterm babies. A prospective observational study of preterm infants with a gestational age of less than 28 weeks, and a hemodynamic significant PDA, requires intravenous ibuprofen or surgical closure. All patients were monitored with electrical velocimetry before treatment and through the following 72 h. Two groups were defined, ibuprofen and surgical closure. Variations of cardiac output were analyzed from the basal situation and at 1, 8, 24, 48, and 72 h on each group. During a 12-month period, 18 patients were studied. The median gestational age in the ibuprofen group (12/18) was 26 +5  weeks (25 +5 -27 +3 ) with a median birth weight of 875 (670-1010) g. The cardiac output index (CI) value was 0.29 l/kg/min (0.24-0.34). Among the patients with confirmed ductus closure (50%), a significant CI decrease was shown (0.24 vs 0.29 l/kg/min; P 0.03) after 72 h (three ibuprofen doses). A statistically significant decrease in systolic volume (SVI) was found: 1.62 vs 1.88 ml/kg, P 0.03 with a decrease in contractility (ICON), 85 vs 140, P 0.02. The gestational age in the surgical group (6/18) was 25 +2  weeks (24-26 +3 ) with a median weight of 745 (660-820) g. All patients in this group showed a decrease in the immediate postoperative CI (1 h after surgery) 0.24 vs 0.30 l/kg/min, P 0.05, and a significant decrease in contractility (ICON 77 vs 147, P 0.03). In addition, a no statistically significant decrease in SVI (1.54 vs 1.83 ml/kg, P 0.06), as well as an increase in systemic vascular resistance (10,615 vs 8797 dyn/cm 2 , P 0.08), were detected. This deterioration was transient without significant differences in the remaining periods of time evaluated. The surgical closure

Oral Consumption of Vitamin K2 for 8 Weeks Associated With Increased Maximal Cardiac Output During Exercise.

Science.gov (United States)

McFarlin, Brian K; Henning, Andrea L; Venable, Adam S

2017-07-01

Background • Vitamin K1 and K2 are not typically common in a Western diet because they are found in a variety of fermented foods. Vitamin K2 in particular has been demonstrated to restore mitochondrial function and has a key role in production of mitochondrial adenosine triphosphate. Thus, it is reasonable to speculate that dietary supplementation with vitamin K2 could increase the function of muscle with high mitochondrial content (ie, skeletal and cardiac muscle). Objective • The purpose of this study was to determine if 8 wk of dietary supplementation with Vitamin K2 could alter cardiovascular responses to a graded cycle ergometer test. Design • The study was a randomized controlled trial. Setting • The study took place in the Applied Physiology Laboratory of the Department of Biological Sciences at the University of North Texas (Denton, TX, USA). Participants • Participants were aerobically trained males and female athletes (N = 26). Intervention • Participants were randomly assigned either to a control group that received a rice flour placebo or to an intervention group that received vitamin K2. For weeks 1 to 4, participants received 300 mg/d; for weeks 5 to 8, they received 150 mg/d. Subjects assigned to the control group received similar doses to mirror the intervention group. Subjects consumed the supplements during an 8-wk period while they maintained their typical exercise habits. Outcome Measures • At baseline and postintervention, participants completed a standard, graded exercise test on an electronically braked cycle ergometer. Before the test, participants were fitted with a mouth piece, and their oxygen consumption, carbon dioxide production, respiratory rate, and respiratory exchange ratio were measured. In addition, participants were fitted with skin-mounted electrodes that measured noninvasive cardiac output, stroke volume, and heart rate. To assess the cumulative exercise change, an area-under-the-curve (AUC) value was calculated

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

CARDIAC FUNCTION AND IRON CHELATION IN THALASSEMIA MAJOR AND INTERMEDIA: A REVIEW OF THE UNDERLYING PATHOPHYSIOLOGY AND APPROACH TO CHELATION MANAGEMENT

Directory of Open Access Journals (Sweden)

Athanasios Aessopos

2009-07-01

Full Text Available Heart disease is the leading cause of mortality and one of the main causes of morbidity in beta-thalassemia. Patients with homozygous thalassemia may have either a severe phenotype which is usually transfusion dependent or a milder form that is thalassemia intermedia.  The two main factors that determine cardiac disease in homozygous β thalassemia are the high output state that results from chronic tissue hypoxia, hypoxia-induced compensatory reactions and iron overload.  The high output state playing a major role in thalassaemia intermedia and the iron load being more significant in the major form. Arrhythmias, vascular involvement that leads to an increased pulmonary vascular resistance and an increased systemic vascular stiffness and valvular abnormalities also contribute to the cardiac dysfunction in varying degrees according to the severity of the phenotype.  Endocrine abnormalities, infections, renal function and medications can also play a role in the overall cardiac function.  For thalassaemia major, regular and adequate blood transfusions and iron chelation therapy are the mainstays of management. The approach to thalassaemia intermedia, today, is aimed at monitoring for complications and initiating, timely, regular transfusions and/or iron chelation therapy.  Once the patients are on transfusions, then they should be managed in the same way as the thalassaemia major patients.  If cardiac manifestations of dysfunction are present in either form of thalassaemia, high pre transfusion Hb levels need to be maintained in order to reduce cardiac output and appropriate intensive chelation therapy needs to be instituted.  In general recommendations on chelation, today, are usually made according to the Cardiac Magnetic Resonance findings, if available.  With the advances in the latter technology and the ability to tailor chelation therapy according to the MRI findings as well as the availability of three iron chelators, together with

Intraoperative hemodynamic monitoring during liver transplantation: goals and devices

DEFF Research Database (Denmark)

Nissen, Peter; Frederiksen, H J; Secher, N H

2010-01-01

With the introduction of orthotopic liver transplantation (OLT) almost 40 years ago, changes in the cardiovascular system that manifest during the different phases of the operation combined, sometimes with massive hemorrhage in likely critically ill patients have been a challenge. Here hemodynamic...... monitoring of the patients during OLT is addressed with focus on maintaining the patients' central blood volume (CBV) and methods and devices that can serve that purpose are listed. It is considered that a stable CBV maintains cerebral blood flow and oxygenation and thereby the well-being of the patient......, while even a small reduction in blood pressure affects cerebral blood flow and oxygenation if it reflects a reduced CBV and thereby cardiac output. In that regard it is accepted that for the patient going through OLT cardiac output (~8 L/min-1) and also venous oxygen saturation (~85%) are larger than...

Influence of heart motion on cardiac output estimation by means of electrical impedance tomography: a case study

International Nuclear Information System (INIS)

Proença, Martin; Braun, Fabian; Rapin, Michael; Solà, Josep; Lemay, Mathieu; Adler, Andy; Grychtol, Bartłomiej; Bohm, Stephan H; Thiran, Jean-Philippe

2015-01-01

Electrical impedance tomography (EIT) is a non-invasive imaging technique that can measure cardiac-related intra-thoracic impedance changes. EIT-based cardiac output estimation relies on the assumption that the amplitude of the impedance change in the ventricular region is representative of stroke volume (SV). However, other factors such as heart motion can significantly affect this ventricular impedance change. In the present case study, a magnetic resonance imaging-based dynamic bio-impedance model fitting the morphology of a single male subject was built. Simulations were performed to evaluate the contribution of heart motion and its influence on EIT-based SV estimation. Myocardial deformation was found to be the main contributor to the ventricular impedance change (56%). However, motion-induced impedance changes showed a strong correlation (r = 0.978) with left ventricular volume. We explained this by the quasi-incompressibility of blood and myocardium. As a result, EIT achieved excellent accuracy in estimating a wide range of simulated SV values (error distribution of 0.57 ± 2.19 ml (1.02 ± 2.62%) and correlation of r = 0.996 after a two-point calibration was applied to convert impedance values to millilitres). As the model was based on one single subject, the strong correlation found between motion-induced changes and ventricular volume remains to be verified in larger datasets. (paper)

The Association Between Urine Output, Creatinine Elevation, and Death.

Science.gov (United States)

Engoren, Milo; Maile, Michael D; Heung, Michael; Jewell, Elizabeth S; Vahabzadeh, Christie; Haft, Jonathan W; Kheterpal, Sachin

2017-04-01

Acute kidney injury can be defined by a fall in urine output, and urine output criteria may be more sensitive in identifying acute kidney injury than traditional serum creatinine criteria. However, as pointed out in the Kidney Disease Improving Global Outcome guidelines, the association of urine output with subsequent creatinine elevations and death is poorly characterized. The purpose of this study was to determine what degrees of reduced urine output are associated with subsequent creatinine elevation and death. This was a retrospective cohort study of adult patients (age ≥18 years) cared for in a cardiovascular intensive care unit after undergoing cardiac operations in a tertiary care university medical center. All adult patients who underwent cardiac operations and were not receiving dialysis preoperatively were studied. The development of acute kidney injury was defined as an increase in creatinine of more than 0.3 mg/dL or by more than 50% above baseline by postoperative day 3. Acute kidney injury developed in 1,061 of 4,195 patients (25%). Urine output had moderate discrimination in predicting subsequent acute kidney injury (C statistic = .637 ± .054). Lower urine output and longer duration of low urine output were associated with greater odds of developing acute kidney injury and death. We found that there is similar accuracy in using urine output corrected for actual, ideal, or adjusted weight to discriminate future acute kidney injury by creatinine elevation and recommend using actual weight for its simplicity. We also found that low urine output is associated with subsequent acute kidney injury and that the association is greater for lower urine output and for low urine output of longer durations. Low urine output (creatinine elevation, is independently associated with mortality. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

A New Device to Automate the Monitoring of Critical Patients’ Urine Output

Directory of Open Access Journals (Sweden)

Abraham Otero

2014-01-01

Full Text Available Urine output (UO is usually measured manually each hour in acutely ill patients. This task consumes a substantial amount of time. Furthermore, in the literature there is evidence that more frequent (minute-by-minute UO measurement could impact clinical decision making and improve patient outcomes. However, it is not feasible to manually take minute-by-minute UO measurements. A device capable of automatically monitoring UO could save precious time of the healthcare staff and improve patient outcomes through a more precise and continuous monitoring of this parameter. This paper presents a device capable of automatically monitoring UO. It provides minute by minute measures and it can generate alarms that warn of deviations from therapeutic goals. It uses a capacitive sensor for the measurement of the UO collected within a rigid container. When the container is full, it automatically empties without requiring any internal or external power supply or any intervention by the nursing staff. In vitro tests have been conducted to verify the proper operation and accuracy in the measures of the device. These tests confirm the viability of the device to automate the monitoring of UO.

Therapeutic drug monitoring of digoxin in cardiac heart failure outpatients: comparisons of two analytical methods

Directory of Open Access Journals (Sweden)

Isabel Cristina Medeiros Barros

2014-01-01

Full Text Available Objective: To compare two analytical techniques used in the determination of plasma digoxin (LC-MS/MS and immunoassay and to verify which one better answer the need of the clinical monitoring routine of patients with cardiac heart failure. Method: The clinical findings in 15 cardiac heart failure (CHF outpatients of the Cardiac Heart Service of the Goias Federal University Clinical Hospital were investigated. Blood samples of the patients were collected and analysed by Immunoassay and by Liquid Chromatography coupled to Mass Spectrometry (LC-MS/MS. Results: The results of the statistic test (Student p = 0,05 showed a significant difference between the analytical methods: immunoassay concentrations were higher than the concentrations determined by LCMS/ MS. The explanation may be because immunoassay method measures digoxin plus other metabolites and endogenous substances, while the LC-MS/MS method measures only the digoxin molecule. None of the patients, showed relevant clinical data suggestive of digitalis intoxication, even several drugs with potential interaction were associated with treatment. Conclusion: It was concluded, therefore, that LC-MS/MS me thod is safer, more selective and specific than immunoassay, being an option for therapeutic drug monitoring of digoxin, since the reference values would be obtain for digoxinemia by LC-MS/MS.

The effect of garden designs on mood and heart output in older adults residing in an assisted living facility.

Science.gov (United States)

Goto, Seiko; Park, Bum-Jin; Tsunetsugu, Yuko; Herrup, Karl; Miyazaki, Yoshifumi

2013-01-01

The objective of this study is to trace short-term changes in mood and heart function in elderly individuals in response to exposure to different landscaped spaces. Nineteen elderly but cognitively intact residents of an assisted living facility participated in the study. They were exposed to three landscaped spaces: a Japanese style garden, an herb garden, and a simple landscaped area planted with a single tree. To assess the effect of different landscaped spaces on older adults, individuals were monitored for mood and cardiac function in response to short exposures to spaces. Mood state was assessed using Profile of Mood States (POMS) before and after viewing the spaces. Cardiac output was assessed using a portable electrocardiograph monitor before and during the viewing. We found that the structured gardens evoked greater responses in all outcome measures. Scores on the POMS improved after observation of the two organized gardens compared to responses to the simple landscaped space with a single tree. During the observation period, heart rate was significantly lower in the Japanese garden than in the other environments, and sympathetic function was significantly lower as well. We conclude that exposure to organized gardens can affect both the mood and cardiac physiology of elderly individuals. Our data further suggest that these effects can differ depending on the types of landscape to which an individual is exposed. Elderly, Japanese garden, herb garden, heart rate, mood, healing environmentPreferred Citation: Goto, S., Park, B-J., Tsunetsugu, Y., Herrup, K., & Miyazaki, Y. (2013). The effect of garden designs on mood and heart output in older adults residing in an assisted living facility. Health Environments Research & Design Journal 6(2), pp 27-42.

Relationship between cardiac function and resting cerebral blood flow: MRI measurements in healthy elderly subjects.

Science.gov (United States)

Henriksen, Otto M; Jensen, Lars T; Krabbe, Katja; Larsson, Henrik B W; Rostrup, Egill

2014-11-01

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 cardiac output were measured in 31 healthy subjects 50-75 years old using magnetic resonance imaging techniques. Mean values of CBF, cardiac output and cardiac index were 43.6 ml per 100 g min(-1), 5.5 l min(-1) and 2.7 l min(-1) m(-2), respectively, in males, and 53.4 ml per 100 g min(-1), 4.3 l min(-1) 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 a gender-related inverse association of increased low-to-high-frequency power ratio with CBF and fractional brain flow. The findings do not support a direct effect of cardiac function on CBF, but demonstrates gender-related differences in cardiac output distribution. We propose fractional brain flow as a novel index that may be a useful marker of adequate brain perfusion in the context of ageing as well as cardiovascular disease. © 2013 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

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

Directory of Open Access Journals (Sweden)

Ole Broch

2016-01-01

Full Text Available 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 (COTPTD and by nine pulse contour algorithms (COX1–9. 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 COTPTD and COX1–9 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.

Implementing an institution-wide quality improvement policy to ensure appropriate use of continuous cardiac monitoring: a mixed-methods retrospective data analysis and direct observation study.

Science.gov (United States)

Rayo, Michael F; Mansfield, Jerry; Eiferman, Daniel; Mignery, Traci; White, Susan; Moffatt-Bruce, Susan D

2016-10-01

Hospitals have been slow to adopt guidelines from the American Heart Association (AHA) limiting the use of continuous cardiac monitoring for fear of missing important patient cardiac events. A new continuous cardiac monitoring policy was implemented at a tertiary-care hospital seeking to monitor only those patients who were clinically indicated and decrease the number of false alarms in order to improve overall alarm response. Leadership support was secured, a cross-functional alarm management task force was created, and a system-wide policy was developed based on current AHA guidelines. Process measures, including cardiac monitoring rate, monitored transport rate, emergency department (ED) boarding rate and the percentage of false, unnecessary and true alarms, were measured to determine the policy's impact on patient care. Outcome measures, including length of stay and mortality rate, were measured to determine the impact on patient outcomes. Cardiac monitoring rate decreased 53.2% (0.535 to 0.251 per patient day, pimprovements in process measures coupled with no adverse effects to patient outcomes suggest that the overall system became more resilient to current and emerging demands. This study indicates that when collaboration across a diverse team is coupled with strong leadership support, policies and procedures such as this one can improve clinical practice and patient care. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

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 HIIT + SIT (39.8 ± 7.3 mL·kg·min to 43.6 ± 6.1 mL·kg·min), HIIT + HIITHI (41.1 ± 4.9 mL·kg·min to 44.6 ± 7.0 mL·kg·min), and HIIT + PER (39.5 ± 5.6 mL·kg·min to 44.1 ± 5.4 mL·kg·min) occurred which were mediated by significant increases in maximal CO (20.0 ± 3.1 L·min to 21.7 ± 3.2 L·min, P = 0.04). Maximal stroke volume was increased with HIIT (P = 0.04), although there was no change in maximal HR (P = 0.88) or arteriovenous O2 difference (P = 0.36). These CO data are accurate and represent the mean changes from pre- to post-HIIT across all three training groups. Increases in V˙O2max exhibited in response to different HIIT regimes are due to improvements in oxygen delivery.

Effects of cardiac output on the onset of rocuronium-induced neuromuscular block in elderly patients.

Science.gov (United States)

Shiraishi, Naoki; Aono, Mayu; Kameyama, Yasuhito; Yamamoto, Mai; Kitajima, Osamu; Suzuki, Takahiro

2018-05-21

The aim of this study was to elucidate the relationship between the onset of rocuronium-induced neuromuscular block and arterial pressure-based cardiac output (CO) in elderly patients. Forty elderly patients aged 65-83 years were enrolled in this study. After induction of anesthesia, contractions of the adductor pollicis muscle to ulnar nerve train-of-four stimulation were acceleromyographically evaluated and 1 mg/kg rocuronium was administered following CO measurement. The correlation between onset of rocuronium action and CO was analyzed. The mean [SD] CO reduced after induction of anesthesia from 5.1 [1.8] L/min to 3.8 [1.1] L/min. The onset time of rocuronium-induced neuromuscular block was 110.3 [23.9] s (range 60-165). There was a statistically significant inverse correlation between the onset time of rocuronium and CO [onset time (s) = - 13.2·CO + 159.7, R 2  = 0.376]. In the elderly, CO influences the onset of action of rocuronium.

Increased cardiac output and maximal oxygen uptake in response to ten sessions of high intensity interval training.

Science.gov (United States)

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

2018-01-01

Increases in maximal oxygen uptake (VO2max) are widely reported in response to completion of high intensity interval training (HIIT), yet the mechanism explaining this result is poorly understood. This study examined changes in VO2max and cardiac output (CO) in response to 10 sessions of low-volume HIIT. Participants included 30 active men and women (mean age and VO2max=22.9±5.4 years and 39.6±5.6 mL/kg/min) who performed HIIT and 30 men and women (age and VO2max=25.7±4.5 years and 40.7±5.2 mL/kg/min) who served as non-exercising controls (CON). High intensity interval training consisted of 6-10 s bouts of cycling per session at 90-110 percent peak power output (PPO) interspersed with 75 s recovery. Before and after training, progressive cycling to exhaustion was completed during which CO, stroke volume (SV), and heart rate (HR) were estimated using thoracic impedance. To confirm VO2max attainment, a verification test was completed after progressive cycling at a work rate equal to 110%PPO. Data demonstrated significant improvements in VO2max (2.71±0.63 L/min to 2.86±0.63 L/min, Psessions of HIIT is due to improvements in oxygen delivery.

Toll-Like Receptor 9 Promotes Cardiac Inflammation and Heart Failure during Polymicrobial Sepsis

Directory of Open Access Journals (Sweden)

Ralph Lohner

2013-01-01

Full Text Available Background. Aim was to elucidate the role of toll-like receptor 9 (TLR9 in cardiac inflammation and septic heart failure in a murine model of polymicrobial sepsis. Methods. Sepsis was induced via colon ascendens stent peritonitis (CASP in C57BL/6 wild-type (WT and TLR9-deficient (TLR9-D mice. Bacterial load in the peritoneal cavity and cardiac expression of inflammatory mediators were determined at 6, 12, 18, 24, and 36 h. Eighteen hours after CASP cardiac function was monitored in vivo. Sarcomere length of isolated cardiomyocytes was measured at 0.5 to 10 Hz after incubation with heat-inactivated bacteria. Results. CASP led to continuous release of bacteria into the peritoneal cavity, an increase of cytokines, and differential regulation of receptors of innate immunity in the heart. Eighteen hours after CASP WT mice developed septic heart failure characterised by reduction of end-systolic pressure, stroke volume, cardiac output, and parameters of contractility. This coincided with reduced cardiomyocyte sarcomere shortening. TLR9 deficiency resulted in significant reduction of cardiac inflammation and a sustained heart function. This was consistent with reduced mortality in TLR9-D compared to WT mice. Conclusions. In polymicrobial sepsis TLR9 signalling is pivotal to cardiac inflammation and septic heart failure.

The effects of malnutrition on cardiac function in African children.

Science.gov (United States)

Silverman, Jonathan A; Chimalizeni, Yamikani; Hawes, Stephen E; Wolf, Elizabeth R; Batra, Maneesh; Khofi, Harriet; Molyneux, Elizabeth M

2016-02-01

Cardiac dysfunction may contribute to high mortality in severely malnourished children. Our objective was to assess the effect of malnutrition on cardiac function in hospitalised African children. Prospective cross-sectional study. Public referral hospital in Blantyre, Malawi. We enrolled 272 stable, hospitalised children ages 6-59 months, with and without WHO-defined severe acute malnutrition. Cardiac index, heart rate, mean arterial pressure, stroke volume index and systemic vascular resistance index were measured by the ultrasound cardiac output monitor (USCOM, New South Wales, Australia). We used linear regression with generalised estimating equations controlling for age, sex and anaemia. Our primary outcome, cardiac index, was similar between those with and without severe malnutrition: difference=0.22 L/min/m(2) (95% CI -0.08 to 0.51). No difference was found in heart rate or stroke volume index. However, mean arterial pressure and systemic vascular resistance index were lower in children with severe malnutrition: difference=-8.6 mm Hg (95% CI -12.7 to -4.6) and difference=-200 dyne s/cm(5)/m(2) (95% CI -320 to -80), respectively. In this largest study to date, we found no significant difference in cardiac function between hospitalised children with and without severe acute malnutrition. Further study is needed to determine if cardiac function is diminished in unstable malnourished children. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Human technology after cardiac epigenesis. Artificial heart versus cardiac transplantation.

Science.gov (United States)

Losman, J G

1977-09-24

Cardiovascular disease is the chief cause of death in technologically advanced countries and accounts for more than 50% of all deaths in the USA. For a patient with end-stage cardiac failure the only treatment presently available is organ replacement, either by transplantation or by the use of a mechanical heart. Transplantation has demonstrated its value: survival of more than 8 years and restoration of a normal quality of life to patients who were in end-stage cardiac decompensation. However, the prospect of routine clinical application of an artificial heart remains distant. The development of a totally implantable artificial heart still presents a series of challenging engineering problems with regard to strict constraints of size, weight, blood-material compatibility, adaptability of output to demand, efficiency and reliability of the power supply, and safety if nuclear fuel is used. The totally artificial heart is presently not an alternative to the cardiac allograft, but could provide short-term support for patients awaiting cardiac transplantation.

Urine Biochemistry in the Early Postoperative Period after Cardiac Surgery: Role in Acute Kidney Injury Monitoring

Directory of Open Access Journals (Sweden)

Alexandre Toledo Maciel

2013-01-01

Full Text Available We have recently suggested that sequential urine electrolyte measurement in critically ill patients may be useful in monitoring kidney function. Cardiac surgery is one of the leading causes of acute kidney injury (AKI in the intensive care unit (ICU. In this paper, we describe the sequential behavior of urine electrolytes in three patients in the early (first 60 hours postoperative period after cardiac surgery according to AKI status: no AKI, transient AKI, and persistent AKI. We have found that the patient with no AKI had stable and high concentrations of sodium (NaU and chloride (ClU in sequential spot samples of urine. AKI development was characterized in the other two patients by decreases in NaU and ClU, which have started early after ICU admission. Transient AKI was marked by also transient and less severe decreases in NaU and ClU. Persistent AKI was marked by the less favorable clinical course with abrupt and prolonged declines in NaU and ClU values. These electrolytes in urine had a behavior like a “mirror image” in comparison with that of serum creatinine. We suggest that sequential urine electrolytes are useful in monitoring acute kidney injury development in the early postoperative period after cardiac surgery.

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

[Meta-analyses on measurement precision of non-invasive hemodynamic monitoring technologies in adults].

Science.gov (United States)

Pestel, G; Fukui, K; Higashi, M; Schmidtmann, I; Werner, C

2018-06-01

An ideal non-invasive monitoring system should provide accurate and reproducible measurements of clinically relevant variables that enables clinicians to guide therapy accordingly. The monitor should be rapid, easy to use, readily available at the bedside, operator-independent, cost-effective and should have a minimal risk and side effect profile for patients. An example is the introduction of pulse oximetry, which has become established for non-invasive monitoring of oxygenation worldwide. A corresponding non-invasive monitoring of hemodynamics and perfusion could optimize the anesthesiological treatment to the needs in individual cases. In recent years several non-invasive technologies to monitor hemodynamics in the perioperative setting have been introduced: suprasternal Doppler ultrasound, modified windkessel function, pulse wave transit time, radial artery tonometry, thoracic bioimpedance, endotracheal bioimpedance, bioreactance, and partial CO 2 rebreathing have been tested for monitoring cardiac output or stroke volume. The photoelectric finger blood volume clamp technique and respiratory variation of the plethysmography curve have been assessed for monitoring fluid responsiveness. In this manuscript meta-analyses of non-invasive monitoring technologies were performed when non-invasive monitoring technology and reference technology were comparable. The primary evaluation criterion for all studies screened was a Bland-Altman analysis. Experimental and pediatric studies were excluded, as were all studies without a non-invasive monitoring technique or studies without evaluation of cardiac output/stroke volume or fluid responsiveness. Most studies found an acceptable bias with wide limits of agreement. Thus, most non-invasive hemodynamic monitoring technologies cannot be considered to be equivalent to the respective reference method. Studies testing the impact of non-invasive hemodynamic monitoring technologies as a trend evaluation on outcome, as well as

Cardiac contractility, central haemodynamics and blood pressure regulation during semistarvation

DEFF Research Database (Denmark)

Stokholm, K H; Breum, L; Astrup, A

1991-01-01

pressure (BP) declined. The fall in BP was caused by the reduction in cardiac output as the total peripheral resistance was unchanged. Finally, the decline in total blood volume was not significant. These findings together with a reduction in heart rate indicated that a reduced sympathetic tone via......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...... 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...

Incidence of major vascular events after cardiac surgery: impact of preoperative monitoring with troponin and electrocardiogram

International Nuclear Information System (INIS)

Sandra M Quiroga; Juan C Villar; Luz X, Martinez

2009-01-01

Recent demographic changes have led to an increased risk of major vascular events among patients undergoing non-cardiac surgery. Troponin and electrocardiogram monitoring would further identify these major vascular events. Methods: we prospectively collected data on eligible patients (non-selected individuals aged 45 or older undergoing non-cardiac surgery under general or regional anesthesia in two hospitals in Bucaramanga, with expected length of stay longer than 24 hours) during a time-interrupted series,before and after postoperative diagnostic monitoring (blinded assessment of troponin T and electrocardiograms ignoring clinical data). For the period before the intervention (usual clinical care),two independent reviewers extracted clinical information from clinical histories (of all eligible patients from 3 randomly-selected months of 2005). For the period after diagnostic monitoring, we followed 100 consecutive eligible patients. Primary outcome was a composite of major vascular events within hospital, including myocardial infarction (defined as any troponin elevation associated with electrocardiographic changes suggesting ischemia, regardless of symptoms). Results: we included 534 clinical charts and 100 prospective surgical patients (mean age 62.2, SD 12.9 years; 56% women). The more frequent surgical procedures were orthopedics (26.8%) followed by abdominal (20.2%).The incidence of major vascular events recorded in clinical charts was 2.8%, compared with 7% among monitored patients (p=0,071). All four myocardial infarctions identified among the later group were silent. Conclusion: postoperative monitoring with troponin and electrocardiography identified a higher proportion of major vascular events, mainly silent myocardial infarctions.

Feasibility of Stereo-Infrared Tracking to Monitor Patient Motion During Cardiac SPECT Imaging

OpenAIRE

Beach, Richard D.; Pretorius, P. Hendrik; Boening, Guido; Bruyant, Philippe P.; Feng, Bing; Fulton, Roger R.; Gennert, Michael A.; Nadella, Suman; King, Michael A.

2004-01-01

Patient motion during cardiac SPECT imaging can cause diagnostic imaging artifacts. We investigated the feasibility of monitoring patient motion using the Polaris motion-tracking system. This system uses passive infrared reflection from small spheres to provide real-time position data with vendor stated 0.35 mm accuracy and 0.2 mm repeatability. In our configuration, the Polaris system views through the SPECT gantry toward the patient's head. List-mode event data was temporally synchronized w...

Association of HeartMate II left ventricular assist device flow estimate with thermodilution cardiac output.

Science.gov (United States)

Hasin, Tal; Huebner, Marianne; Li, Zhuo; Brown, Daniel; Stulak, John M; Boilson, Barry A; Joyce, Lyle; Pereira, Naveen L; Kushwaha, Sudhir S; Park, Soon J

2014-01-01

Cardiac output (CO) assessment is important in treating patients with heart failure. Durable left ventricular assist devices (LVADs) provide essentially all CO. In currently used LVADs, estimated device flow is generated by a computerized algorithm. However, LVAD flow estimate may be inaccurate in tracking true CO. We correlated LVAD (HeartMate II) flow with thermodilution CO during postoperative care (day 2-10 after implant) in 81 patients (5,616 paired measurements). Left ventricular assist device flow and CO correlated with a low correlation coefficient (r = 0.42). Left ventricular assist device readings were lower than CO measurements by approximately 0.36 L/min, trending for larger difference with higher values. Left ventricular assist device flow measurements showed less temporal variability compared with CO. Grouping for simultaneous measured blood pressure (BP device flow generally trends with measured CO, but large variability exists, hence flow measures should not be assumed to equal with CO. Clinicians should take into account variables such as high CO, BP, and opening of the aortic valve when interpreting LVAD flow readout. Direct flow sensors incorporated in the LVAD system may allow for better estimation.

Clip-on wireless wearable microwave sensor for ambulatory cardiac monitoring.

Science.gov (United States)

Fletcher, Richard R; Kulkarni, Sarang

2010-01-01

We present a new type of non-contact sensor for use in ambulatory cardiac monitoring. The sensor operation is based on a microwave Doppler technique; however, instead of detecting the heart activity from a distance, the sensor is placed on the patient's chest over the clothing. The microwave sensor directly measures heart movement rather than electrical activity, and is thus complementary to ECG. The primary advantages of the microwave sensor includes small size, light weight, low power, low-cost, and the ability to operate through clothing. We present a sample sensor design that incorporates a 2.4 GHz Doppler circuit, integrated microstrip patch antenna, and microntroller with 12-bit ADC data sampling. The prototype sensor also includes a wireless data link for sending data to a remote PC or mobile phone. Sample data is shown for several subjects and compared to data from a commercial portable ECG device. Data collected from the microwave sensor exhibits a significant amount of features, indicating possible use as a tool for monitoring heart mechanics and detection of abnormalities such as fibrillation and akinesia.

Cerebral oxygenation monitoring in patients with bilateral carotid stenosis undergoing urgent cardiac surgery: Observational case series

Directory of Open Access Journals (Sweden)

Dincer Aktuerk

2016-01-01

Full Text Available Background: Patients with significant bilateral carotid artery stenosis requiring urgent cardiac surgery have an increased risk of stroke and death. The optimal management strategy remains inconclusive, and the available evidence does not support the superiority of one strategy over another. Materials and Methods: A number of noninvasive strategies have been developed for minimizing perioperative stroke including continuous real-time monitoring of cerebral oxygenation with near-infrared spectroscopy (NIRS. The number of patients presenting with this combination (bilateral significant carotid stenosis requiring urgent cardiac surgery in any single institution will be small and hence there is a lack of large randomized studies. Results: This case series describes our early experience with NIRS in a select group of patients with significant bilateral carotid stenosis undergoing urgent cardiac surgery (n = 8. In contrast to other studies, this series is a single surgeon, single center study, where the entire surgery (both distal ends and proximal ends was performed during single aortic clamp technique, which effectively removes several confounding variables. NIRS monitoring led to the early recognition of decreased cerebral oxygenation, and corrective steps (increased cardiopulmonary bypass flow, increased pCO 2 , etc., were taken. Conclusion: The study shows good clinical outcome with the use of NIRS. This is our "work in progress," and we aim to conduct a larger study.

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.

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

A remote monitor of bed patient cardiac vibration, respiration and movement.

Science.gov (United States)

Mukai, Koji; Yonezawa, Yoshiharu; Ogawa, Hidekuni; Maki, Hiromichi; Caldwell, W Morton

2009-01-01

We have developed a remote system for monitoring heart rate, respiration rate and movement behavior of at-home elderly people who are living alone. The system consists of a 40 kHz ultrasonic transmitter and receiver, linear integrated circuits, a low-power 8-bit single chip microcomputer and an Internet server computer. The 40 kHz ultrasonic transmitter and receiver are installed into a bed mattress. The transmitted signal diffuses into the bed mattress, and the amplitude of the received ultrasonic wave is modulated by the shape of the mattress and parameters such as respiration, cardiac vibration and movement. The modulated ultrasonic signal is received and demodulated by an envelope detection circuit. Low, high and band pass filters separate the respiration, cardiac vibration and movement signals, which are fed into the microcontroller and digitized at a sampling rate of 50 Hz by 8-bit A/D converters. The digitized data are sent to the server computer as a serial signal. This computer stores the data and also creates a graphic chart of the latest hour. The person's family or caregiver can download this chart via the Internet at any time.

Benefit of neurophysiologic monitoring for pediatric cardiac surgery.

Science.gov (United States)

Austin, E H; Edmonds, H L; Auden, S M; Seremet, V; Niznik, G; Sehic, A; Sowell, M K; Cheppo, C D; Corlett, K M

1997-11-01

Pediatric patients undergoing repair of congenital cardiac abnormalities have a significant risk of an adverse neurologic event. Therefore this retrospective cohort study examined the potential benefit of interventions based on intraoperative neurophysiologic monitoring in decreasing both postoperative neurologic sequelae and length of hospital stay as a cost proxy. With informed parental consent approved by the institutional review board, electroencephalography, transcranial Doppler ultrasonic measurement of middle cerebral artery blood flow velocity, and transcranial near-infrared cerebral oximetry were monitored in 250 patients. An interventional algorithm was used to detect and correct specific deficiencies in cerebral perfusion or oxygenation or to increase cerebral tolerance to ischemia or hypoxia. Noteworthy changes in brain perfusion or metabolism were observed in 176 of 250 (70%) patients. Intervention that altered patient management was initially deemed appropriate in 130 of 176 (74%) patients with neurophysiologic changes. Obvious neurologic sequelae (i.e., seizure, movement, vision or speech disorder) occurred in five of 74 (7%) patients without noteworthy change, seven of 130 (6%) patients with intervention, and 12 of 46 (26%) patients without intervention (p = 0.001). Survivors' median length of stay was 6 days in the no-change and intervention groups but 9 days in the no-intervention group. In addition, the percentage of patients in the no-intervention group discharged from the hospital within 1 week (32%) was significantly less than that in either the intervention (51%, p = 0.05) or no-change (58%, p = 0.01) groups. On the basis of an estimated hospital neurologic complication cost of $1500 per day, break-even analysis justified a hospital expenditure for neurophysiologic monitoring of $2142 per case. Interventions based on neurophysiologic monitoring appear to decrease the incidence of postoperative neurologic sequelae and reduce the length of stay

Milrinone ameliorates cardiac mechanical dysfunction after hypothermia in an intact rat model.

Science.gov (United States)

Dietrichs, Erik Sveberg; Kondratiev, Timofei; Tveita, Torkjel

2014-12-01

Rewarming from hypothermia is often complicated by cardiac dysfunction, characterized by substantial reduction in stroke volume. Previously we have reported that inotropic agents, working via cardiac β-receptor agonism may exert serious side effects when applied to treat cardiac contractile dysfunction during rewarming. In this study we tested whether Milrinone, a phosphodiesterase III inhibitor, is able to ameliorate such dysfunction when given during rewarming. A rat model designed for circulatory studies during experimental hypothermia with cooling to a core temperature of 15°C, stable hypothermia at this temperature for 3h and subsequent rewarming was used, with a total of 3 groups: (1) a normothermic group receiving Milrinone, (2) a hypothermic group receiving Milrinone the last hour of hypothermia and during rewarming, and (3) a hypothermic saline control group. Hemodynamic function was monitored using a conductance catheter introduced to the left ventricle. After rewarming from 15°C, stroke volume and cardiac output returned to within baseline values in Milrinone treated animals, while these variables were significantly reduced in saline controls. Milrinone ameliorated cardiac dysfunction during rewarming from 15°C. The present results suggest that at low core temperatures and during rewarming from such temperatures, pharmacologic efforts to support cardiovascular function is better achieved by substances preventing cyclic AMP breakdown rather than increasing its formation via β-receptor stimulation. Copyright © 2014 Elsevier Inc. All rights reserved.

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

Systemic arteriovenous malformations as a cause of cardiac failure: Treatment with embolization

International Nuclear Information System (INIS)

Smith, E.J.; Hemingway, A.P.; Allison, D.J.

1987-01-01

Massive cogenital systemic arteriovenous malformations (AVMs) present considerable management problems for clinicians. Their size, position, and vascularity make successful surgical reaction impossible. Attempts at resection produce only temporary relief of symptoms and cause further disfigurement. Large AVMs give rise to pain, swelling, and distal ischaemia, can erode bone, and give rise to life-threatening hemorrhage, and a massive left or right shunt causes high-output cardiac failure and death. Ten patients (age range, 5-50 years; mean 26 years) have massive AVMs giving rise to high-output cardiac failure (26-28 liters). These patients (seven male, three female), have undergone a total of 43 embolization procedures. The advent of nonionic contrast media, digital subtraction angiography, steel coils, and balloons allows us to successfully treat these patients who until recently were condemned to die in high-output cardiac failure

Differential-output B-dot and D-dot monitors for current and voltage measurements on a 20-MA, 3-MV pulsed-power accelerator

Directory of Open Access Journals (Sweden)

T. C. Wagoner

2008-10-01

Full Text Available We have developed a system of differential-output monitors that diagnose current and voltage in the vacuum section of a 20-MA 3-MV pulsed-power accelerator. The system includes 62 gauges: 3 current and 6 voltage monitors that are fielded on each of the accelerator’s 4 vacuum-insulator stacks, 6 current monitors on each of the accelerator’s 4 outer magnetically insulated transmission lines (MITLs, and 2 current monitors on the accelerator’s inner MITL. The inner-MITL monitors are located 6 cm from the axis of the load. Each of the stack and outer-MITL current monitors comprises two separate B-dot sensors, each of which consists of four 3-mm-diameter wire loops wound in series. The two sensors are separately located within adjacent cavities machined out of a single piece of copper. The high electrical conductivity of copper minimizes penetration of magnetic flux into the cavity walls, which minimizes changes in the sensitivity of the sensors on the 100-ns time scale of the accelerator’s power pulse. A model of flux penetration has been developed and is used to correct (to first order the B-dot signals for the penetration that does occur. The two sensors are designed to produce signals with opposite polarities; hence, each current monitor may be regarded as a single detector with differential outputs. Common-mode-noise rejection is achieved by combining these signals in a 50-Ω balun. The signal cables that connect the B-dot monitors to the balun are chosen to provide reasonable bandwidth and acceptable levels of Compton drive in the bremsstrahlung field of the accelerator. A single 50-Ω cable transmits the output signal of each balun to a double-wall screen room, where the signals are attenuated, digitized (0.5-ns/sample, numerically compensated for cable losses, and numerically integrated. By contrast, each inner-MITL current monitor contains only a single B-dot sensor. These monitors are fielded in opposite-polarity pairs. The two

Do interindividual differences in cardiac output during submaximal exercise explain differences in exercising muscle oxygenation and ratings of perceived exertion?

Science.gov (United States)

Bentley, Robert F; Jones, Joshua H; Hirai, Daniel M; Zelt, Joel T; Giles, Matthew D; Raleigh, James P; Quadrilatero, Joe; Gurd, Brendon J; Neder, J Alberto; Tschakovsky, Michael E

2018-01-01

Considerable interindividual differences in the Q˙-V˙O2 relationship during exercise have been documented but implications for submaximal exercise tolerance have not been considered. We tested the hypothesis that these interindividual differences were associated with differences in exercising muscle deoxygenation and ratings of perceived exertion (RPE) across a range of submaximal exercise intensities. A total of 31 (21 ± 3 years) healthy recreationally active males performed an incremental exercise test to exhaustion 24 h following a resting muscle biopsy. Cardiac output (Q˙ L/min; inert gas rebreathe), oxygen uptake (V˙O2 L/min; breath-by-breath pulmonary gas exchange), quadriceps saturation (near infrared spectroscopy) and exercise tolerance (6-20; Borg Scale RPE) were measured. The Q˙-V˙O2 relationship from 40 to 160 W was used to partition individuals post hoc into higher (n = 10; 6.3 ± 0.4) versus lower (n = 10; 3.7 ± 0.4, P exercise (all P > 0.4). Lower cardiac responders had greater leg (P = 0.027) and whole body (P = 0.03) RPE only at 185 W, but this represented a higher %peak V˙O2 in lower cardiac responders (87 ± 15% vs. 66 ± 12%, P = 0.005). Substantially lower Q˙-V˙O2 in the lower responder group did not result in altered RPE or exercising muscle deoxygenation. This suggests substantial recruitment of blood flow redistribution in the lower responder group as part of protecting matching of exercising muscle oxygen delivery to demand. © 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

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

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.

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.

Monitoring the consistency of the dynalyser output via digital display unit and calculated practical peak voltage

International Nuclear Information System (INIS)

Wan Hazlinda Ismail; Muhammad Jamal Mohd Isa; Abdul Aziz Mohd Ramli; Shahrul Azlan Azizan

2010-01-01

This study was carried out to ensure the adequacy and accuracy of the Dynalyser Digital Display unit for measuring the true kVp from the invasive kVp meter unit during calibration of non-invasive kVp meters. An invasive high voltage divider (dynalyser) coupled to the x-ray system measures the true kilo voltage supplied to the x-ray tube. The kVp output measured was displayed via its digital display unit while its waveform was acquired using a calibrated oscilloscope. The waveform was used to calculate the Practical Peak Voltage (PPV) using the International Standard method adapted from IEC 61676 and treated as the true kVp value. The kVp output was measured at 9 points ranging between 40 kV-120 kV with interval steps of 10 kV and monitored every day. The test result was evaluated for variation of output, intrinsic error and limit of variation in compliance with the IEC standard. Results showed that kVp output measured by the display unit everyday is consistent with variations of not more than ±0.45 kV, intrinsic error of not more than ±0.009 kV and limits of variation of less than 1% which comply with the IEC standard requirement. The kVp output via digital display unit has a total uncertainty of not more than 2.8 kV (k=2) while the PPV output via oscilloscope has total uncertainty of not more than 0.75 kV (k=2). As a conclusion, the dynalyser digital display unit complies with standard requirement and can be used to measure the true kVp output during the calibration of non-invasive kVp meters. (author)

Remote Monitoring of the Heart Condition of Athletes by Measuring the Cardiac Action Potential Propagation Time Using a Wireless Sensor Network

Directory of Open Access Journals (Sweden)

Amang Sudarsono

2016-04-01

Full Text Available Highly performing athletes are susceptible to cardiac damage of several kinds which may be irreversible. The monitoring of heart rate and ECG waveforms from such subjects by wireless sensor networks has been reported in health and sports care documents. However, a more decisive parameter for instant to instant changes would be the time of Cardiac Action Potential Propagation. This time, which can be between 15-20 ms would shoot suddenly in acute stress in highly performing athletes for short durations. Repeated incidents of such rising values will tend to cause irreversible damage to the heart. We developed the technique of measuring this time and reporting it through a wireless sensor network to monitoring station.

Comparison of cardiac output optimization with an automated closed-loop goal-directed fluid therapy versus non standardized manual fluid administration during elective abdominal surgery: first prospective randomized controlled trial.

Science.gov (United States)

Lilot, Marc; Bellon, Amandine; Gueugnon, Marine; Laplace, Marie-Christine; Baffeleuf, Bruno; Hacquard, Pauline; Barthomeuf, Felicie; Parent, Camille; Tran, Thomas; Soubirou, Jean-Luc; Robinson, Philip; Bouvet, Lionel; Vassal, Olivia; Lehot, Jean-Jacques; Piriou, Vincent

2018-01-27

An intraoperative automated closed-loop system for goal-directed fluid therapy has been successfully tested in silico, in vivo and in a clinical case-control matching. This trial compared intraoperative cardiac output (CO) in patients managed with this closed-loop system versus usual practice in an academic medical center. The closed-loop system was connected to a CO monitoring system and delivered automated colloid fluid boluses. Moderate to high-risk abdominal surgical patients were randomized either to the closed-loop or the manual group. Intraoperative final CO was the primary endpoint. Secondary endpoints were intraoperative overall mean cardiac index (CI), increase from initial to final CI, intraoperative fluid volume and postoperative outcomes. From January 2014 to November 2015, 46 patients were randomized. There was a lower initial CI (2.06 vs. 2.51 l min -1 m -2 , p = 0.042) in the closed-loop compared to the control group. No difference in final CO and in overall mean intraoperative CI was observed between groups. A significant relative increase from initial to final CI values was observed in the closed-loop but not the control group (+ 28.6%, p = 0.006 vs. + 1.2%, p = 0.843). No difference was found for intraoperative fluid management and postoperative outcomes between groups. There was no significant impact on the primary study endpoint, but this was found in a context of unexpected lower initial CI in the closed-loop group.Trial registry number ID-RCB/EudraCT: 2013-A00770-45. ClinicalTrials.gov Identifier NCT01950845, date of registration: 17 September 2013.

Omega-3 fatty acid supplementation enhances stroke volume and cardiac output during dynamic exercise.

Science.gov (United States)

Walser, Buddy; Stebbins, Charles L

2008-10-01

Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) have beneficial effects on cardiovascular function. We tested the hypotheses that dietary supplementation with DHA (2 g/day) + EPA (3 g/day) enhances increases in stroke volume (SV) and cardiac output (CO) and decreases in systemic vascular resistance (SVR) during dynamic exercise. Healthy subjects received DHA + EPA (eight men, four women) or safflower oil (six men, three women) for 6 weeks. Both groups performed 20 min of bicycle exercise (10 min each at a low and moderate work intensity) before and after DHA + EPA or safflower oil treatment. Mean arterial pressure (MAP), heart rate (HR), SV, CO, and SVR were assessed before exercise and during both workloads. HR was unaffected by DHA + EPA and MAP was reduced, but only at rest (88 +/- 5 vs. 83 +/- 4 mm Hg). DHA + EPA augmented increases in SV (14.1 +/- 6.3 vs. 32.3 +/- 8.7 ml) and CO (8.5 +/- 1.0 vs. 10.3 +/- 1.2 L/min) and tended to attenuate decreases in SVR (-7.0 +/- 0.6 vs. -10.1 +/- 1.6 mm Hg L(-1) min(-1)) during the moderate workload. Safflower oil treatment had no effects on MAP, HR, SV, CO or SVR at rest or during exercise. DHA + EPA-induced increases in SV and CO imply that dietary supplementation with these fatty acids can increase oxygen delivery during exercise, which may have beneficial clinical implications for individuals with cardiovascular disease and reduced exercise tolerance.

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

Consumer sleep monitors: is there a baby in the bathwater?

Directory of Open Access Journals (Sweden)

Russo K

2015-11-01

Full Text Available Kathryn Russo,1 Balaji Goparaju,1 Matt T Bianchi1,2 1Department of Neurology, Massachusetts General Hospital, 2Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA Abstract: The rapid expansion of consumer sleep devices is outpacing the validation data necessary to assess the potential use of these devices in clinical and research settings. Common sleep monitoring devices utilize a variety of sensors to track movement as well as cardiac and respiratory physiology. The variety of sensors and user-specific factors offer the potential, at least theoretically, for clinically relevant information. We describe the current challenges for interpretation of consumer sleep monitoring data, since the devices are mainly used in nonmedical contexts (consumer use although medically-definable sleep disorders may commonly occur in this setting. A framework for addressing questions of how certain devices might be useful is offered. We suggest that multistage validation efforts are crucially needed, from the level of sensor data and algorithm output, to extrapolations beyond healthy adults and into other populations and real-world environments. Keywords: movement, cardiac and respiratory physiology, sensor, consumer sleep monitoring data

Endothelial Function as a Possible Significant Determinant of Cardiac Function during Exercise in Patients with Structural Heart Disease

Directory of Open Access Journals (Sweden)

Bonpei Takase

2009-01-01

Full Text Available This study was investigated the role that endothelial function and systemic vascular resistance (SVR play in determining cardiac function reserve during exercise by a new ambulatory radionuclide monitoring system (VEST in patients with heart disease. The study population consisted of 32 patients. The patients had cardiopulmonary stress testing using the treadmill Ramp protocol and the VEST. The anaerobic threshold (AT was autodetermined using the V-slope method. The SVR was calculated by determining the mean blood pressure/cardiac output. Flow-mediated vasodilation (FMD was measured in the brachial artery to evaluate endotheilial function. FMD and the percent change f'rom rest to AT in SVR correlated with those from rest to AT in ejection fraction and peak ejection ratio by VEST, respectively. Our findings suggest that FMD in the brachial artery and the SVR determined by VEST in patients with heart disease can possibly reflect cardiac function reserve during aerobic exercise.

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...

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

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...... 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...

An integrated bioimpedance—ECG gating technique for respiratory and cardiac motion compensation in cardiac PET

International Nuclear Information System (INIS)

Koivumäki, Tuomas; Nekolla, Stephan G; Fürst, Sebastian; Loher, Simone; Schwaiger, Markus; Vauhkonen, Marko; Hakulinen, Mikko A

2014-01-01

Respiratory motion may degrade image quality in cardiac PET imaging. Since cardiac PET studies often involve cardiac gating by ECG, a separate respiratory monitoring system is required increasing the logistic complexity of the examination, in case respiratory gating is also needed. Thus, we investigated the simultaneous acquisition of both respiratory and cardiac gating signals using II limb lead mimicking electrode configuration during cardiac PET scans of 11 patients. In addition to conventional static and ECG-gated images, bioimpedance technique was utilized to generate respiratory- and dual-gated images. The ability of the bioimpedance technique to monitor intrathoracic respiratory motion was assessed estimating cardiac displacement between end-inspiration and -expiration. The relevance of dual gating was evaluated in left ventricular volume and myocardial wall thickness measurements. An average 7.6  ±  3.3 mm respiratory motion was observed in the study population. Dual gating showed a small but significant increase (4 ml, p = 0.042) in left ventricular myocardial volume compared to plain cardiac gating. In addition, a thinner myocardial wall was observed in dual-gated images (9.3  ±  1.3 mm) compared to cardiac-gated images (11.3  ±  1.3 mm, p = 0.003). This study shows the feasibility of bioimpedance measurements for dual gating in a clinical setting. The method enables simultaneous acquisition of respiratory and cardiac gating signals using a single device with standard ECG electrodes. (paper)

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.

Validation, optimisation, and application data in support of the development of a targeted selected ion monitoring assay for degraded cardiac troponin T

Directory of Open Access Journals (Sweden)

Alexander S. Streng

2016-06-01

Full Text Available Cardiac troponin T (cTnT fragmentation in human serum was investigated using a newly developed targeted selected ion monitoring assay, as described in the accompanying article: “Development of a targeted selected ion monitoring assay for the elucidation of protease induced structural changes in cardiac troponin T” [1]. This article presents data describing aspects of the validation and optimisation of this assay. The data consists of several figures, an excel file containing the results of a sequence identity search, and a description of the raw mass spectrometry (MS data files, deposited in the ProteomeXchange repository with id PRIDE: http://www.ebi.ac.uk/pride/archive/projects/PXD003187.

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

Evaluation of the cardiac efficiency by means of functional radiocardiography

Energy Technology Data Exchange (ETDEWEB)

Scheibe, J; Stoll, W [Friedrich-Schiller-Universitaet, Jena (German Democratic Republic). Bereich Medizin

1982-01-01

A new method of evaluating the cardiac efficiency by means of radiocardiography performed on exertion with /sup 113m/InCl is reported. Analysis of stroke volume, end diastolic volume and of the quotient of cardiac output to end diastolic volume on exertion enables an adequate evaluation of the actual myocardial efficiency.

Cardiac function studies

International Nuclear Information System (INIS)

Horn, H.J.

1986-01-01

A total of 27 patients were subjected tointramyocardial sequential scintiscanning (first pass) using 99m-Tc human serum albumin. A refined method is described that is suitable to analyse clinically relevant parameters like blood volume, cardiac output, ejection fraction, stroke volume, enddiastolic and endsystolic volumes as well as pulmonal transition time and uses a complete camaracomputer system adapted to the requirements of a routine procedure. Unless there is special hardware available, the method does not yet appear mature enough to be put into general practice. Its importance recently appeared in a new light due to the advent of particularly shortlived isotopes. For the time being, however, ECG-triggered equilibrium studies are to be preferred for cardiac function tests. (TRV) [de

Cardiac failure due to arteriovenous fistula with brachiocephalic stenosis: a gated heart case study

International Nuclear Information System (INIS)

Abel, G.; Irish, A.; Henderson, A.; Lenzo, N.

2003-01-01

Full text: There are numerous causes of cardiac failure of which the commonest in our community include ischaemic cardiomyopathy, post-viral cardiomyopathy, alcohol-induced cardiomyopathy and drug-induced cardiomyopathy. All these entities cause low output cardiac failure however high output cardiac failure is also well recognised. This includes heart failure related to such conditions as hyperthyroidism, anaemia, pregnancy, beri-beri, and Paget's disease. A rare cause of high output cardiac failure is an arteriovenous fistula. We present an unusual case of a patient with end-stage renal failure on haemodialysis who developed extensive dilatation of their left arm arteriovenous fistula secondary to bachiocephalic vein stenosis. The labelled red blood cell gated heart blood pool study demonstrated decreased left ventricular function and extensive pooling of blood within the tortuous dilated left arm vessels. A follow-up study post-ligation of the arteriovenous fistula showed improvement of the left ventricular ejection fraction. The associated contrast venography findings are also demonstrated. Copyright (2003) The Australian and New Zealand Society of Nuclear Medicine Inc

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...

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

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...

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

(130 (SD 46) vs 78 (SD 29) mumol/l, psyndrome 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......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...

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.

Comparative cardiac toxicity of anthracyclines in vitro and in vivo in the mouse.

Directory of Open Access Journals (Sweden)

Stefano Toldo

Full Text Available PURPOSE: The antineoplastic efficacy of anthracyclines is limited by their cardiac toxicity. In this study, we evaluated the toxicity of doxorubicin, non-pegylated liposomal-delivered doxorubicin, and epirubicin in HL-1 adult cardiomyocytes in culture as well as in the mouse in vivo. METHODS: The cardiomyocytes were incubated with the three anthracyclines (1 µM to assess reactive oxygen generation, DNA damage and apoptotic cell death. CF-1 mice (10/group received doxorubicin, epirubicin or non-pegylated liposomal-doxorubicin (10 mg/kg and cardiac function was monitored by Doppler echocardiography to measure left ventricular ejection fraction (LVEF, heart rate (HR and cardiac output (CO both prior to and 10 days after drug treatment. RESULTS: In HL-1 cells, non-pegylated liposomal-doxorubicin generated significantly less reactive oxygen species (ROS, as well as less DNA damage and apoptosis activation when compared with doxorubicin and epirubicin. Cultured breast tumor cells showed similar sensitivity to the three anthracyclines. In the healthy mouse, non-pegylated liposomal doxorubicin showed a minimal and non-significant decrease in LVEF with no change in HR or CO, compared to doxorubicin and epirubicin. CONCLUSION: This study provides evidence for reduced cardiac toxicity of non-pegylated-liposomal doxorubicin characterized by attenuation of ROS generation, DNA damage and apoptosis in comparison to epirubicin and doxorubicin.

Cardiotoxicity and Cardiac Monitoring During Adjuvant Trastuzumab in Daily Dutch Practice: A Study of the Southeast Netherlands Breast Cancer Consortium

NARCIS (Netherlands)

Seferina, S.C.; Boer, M. de; Derksen, M.W.J.; Berkmortel, F. van den; Kampen, R.J. van; Wouw, A.J. van de; Joore, M.; Peer, P.G.M.; Voogd, A.C.; Tjan-Heijnen, V.C.

2016-01-01

INTRODUCTION: We assessed the incidence and timing of first cardiac events, impact on trastuzumab prescription, and role of left ventricular ejection fraction (LVEF) monitoring in daily practice of trastuzumab-treated patients with human epidermal growth receptor 2 (HER2)-positive early breast

Preliminary application of a novel algorithm to monitor changes in pre-flight total peripheral resistance for prediction of post-flight orthostatic intolerance in astronauts

Science.gov (United States)

Arai, Tatsuya; Lee, Kichang; Stenger, Michael B.; Platts, Steven H.; Meck, Janice V.; Cohen, Richard J.

2011-04-01

Orthostatic intolerance (OI) is a significant challenge for astronauts after long-duration spaceflight. Depending on flight duration, 20-80% of astronauts suffer from post-flight OI, which is associated with reduced vascular resistance. This paper introduces a novel algorithm for continuously monitoring changes in total peripheral resistance (TPR) by processing the peripheral arterial blood pressure (ABP). To validate, we applied our novel mathematical algorithm to the pre-flight ABP data previously recorded from twelve astronauts ten days before launch. The TPR changes were calculated by our algorithm and compared with the TPR value estimated using cardiac output/heart rate before and after phenylephrine administration. The astronauts in the post-flight presyncopal group had lower pre-flight TPR changes (1.66 times) than those in the non-presyncopal group (2.15 times). The trend in TPR changes calculated with our algorithm agreed with the TPR trend calculated using measured cardiac output in the previous study. Further data collection and algorithm refinement are needed for pre-flight detection of OI and monitoring of continuous TPR by analysis of peripheral arterial blood pressure.

Robotic cardiac surgery: an anaesthetic challenge.

Science.gov (United States)

Wang, Gang; Gao, Changqing

2014-08-01

Robotic cardiac surgery with the da Vinci robotic surgical system offers the benefits of a minimally invasive procedure, including a smaller incision and scar, reduced risk of infection, less pain and trauma, less bleeding and blood transfusion requirements, shorter hospital stay and decreased recovery time. Robotic cardiac surgery includes extracardiac and intracardiac procedures. Extracardiac procedures are often performed on a beating heart. Intracardiac procedures require the aid of peripheral cardiopulmonary bypass via a minithoracotomy. Robotic cardiac surgery, however, poses challenges to the anaesthetist, as the obligatory one-lung ventilation (OLV) and CO2 insufflation may reduce cardiac output and increase pulmonary vascular resistance, potentially resulting in hypoxaemia and haemodynamic compromise. In addition, surgery requires appropriate positioning of specialised cannulae such as an endopulmonary vent, endocoronary sinus catheter, and endoaortic clamp catheter under the guidance of transoesophageal echocardiography. Therefore, cardiac anaesthetists should have a working knowledge of these systems, OLV and haemodynamic support. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Roles of PDE1 in Pathological Cardiac Remodeling and Dysfunction.

Science.gov (United States)

Chen, Si; Knight, Walter E; Yan, Chen

2018-04-23

Pathological cardiac hypertrophy and dysfunction is a response to various stress stimuli and can result in reduced cardiac output and heart failure. Cyclic nucleotide signaling regulates several cardiac functions including contractility, remodeling, and fibrosis. Cyclic nucleotide phosphodiesterases (PDEs), by catalyzing the hydrolysis of cyclic nucleotides, are critical in the homeostasis of intracellular cyclic nucleotide signaling and hold great therapeutic potential as drug targets. Recent studies have revealed that the inhibition of the PDE family member PDE1 plays a protective role in pathological cardiac remodeling and dysfunction by the modulation of distinct cyclic nucleotide signaling pathways. This review summarizes recent key findings regarding the roles of PDE1 in the cardiac system that can lead to a better understanding of its therapeutic potential.

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.

Cardiac Acceleration at the Onset of Exercise : A Potential Parameter for Monitoring Progress During Physical Training in Sports and Rehabilitation

NARCIS (Netherlands)

Hettinga, Florentina J.; Monden, Paul G.; van Meeteren, Nico L. U.; Daanen, Hein A. M.

There is a need for easy-to-use methods to assess training progress in sports and rehabilitation research. The present review investigated whether cardiac acceleration at the onset of physical exercise (HRonset) can be used as a monitoring variable. The digital databases of Scopus and PubMed were

Cardiac acceleration at the onset of exercise: A potential parameter for monitoring progress during physical training in sports and rehabilitation

NARCIS (Netherlands)

Hettinga, F.J.; Monden, P.G.; Meeteren, N.L.U. van; Daanen, H.A.M.

2014-01-01

There is a need for easy-to-use methods to assess training progress in sports and rehabilitation research. The present review investigated whether cardiac acceleration at the onset of physical exercise (HRonset) can be used as a monitoring variable. The digital databases of Scopus and PubMed were

Traction force microscopy of engineered cardiac tissues.

Science.gov (United States)

Pasqualini, Francesco Silvio; Agarwal, Ashutosh; O'Connor, Blakely Bussie; Liu, Qihan; Sheehy, Sean P; Parker, Kevin Kit

2018-01-01

Cardiac tissue development and pathology have been shown to depend sensitively on microenvironmental mechanical factors, such as extracellular matrix stiffness, in both in vivo and in vitro systems. We present a novel quantitative approach to assess cardiac structure and function by extending the classical traction force microscopy technique to tissue-level preparations. Using this system, we investigated the relationship between contractile proficiency and metabolism in neonate rat ventricular myocytes (NRVM) cultured on gels with stiffness mimicking soft immature (1 kPa), normal healthy (13 kPa), and stiff diseased (90 kPa) cardiac microenvironments. We found that tissues engineered on the softest gels generated the least amount of stress and had the smallest work output. Conversely, cardiomyocytes in tissues engineered on healthy- and disease-mimicking gels generated significantly higher stresses, with the maximal contractile work measured in NRVM engineered on gels of normal stiffness. Interestingly, although tissues on soft gels exhibited poor stress generation and work production, their basal metabolic respiration rate was significantly more elevated than in other groups, suggesting a highly ineffective coupling between energy production and contractile work output. Our novel platform can thus be utilized to quantitatively assess the mechanotransduction pathways that initiate tissue-level structural and functional remodeling in response to substrate stiffness.

Application of transpulmonary thermodilution monitoring (PiCCO in patient with neurogenic pulmonary edema and acute obstructive hydrocephalus due to a central neurocytoma: A case report

Directory of Open Access Journals (Sweden)

Ryoichi Iwata

2017-06-01

Full Text Available Neurogenic pulmonary edema (NPE is an acute life-threatening complication associated with many forms of central nervous system injury. Its pathophysiology is still debated. We report a patient with acute obstructive hydrocephalus due to a central neurocytoma who also had NPE, for which serial transpulmonary thermodilution monitoring (PiCCO was performed. Insertion of the PiCCO, which provides information about the patient's cardiac output, preload status and amount of lung water, revealed a high pulmonary vascular permeability index (PVPI and low global end-diastolic volume (GEDV without cardiac dysfunction, indicating permeability edema, which led to our changing the therapeutic strategy. Using PiCCO monitoring to balance the preload and extent of pulmonary edema enabled achievement of an optimal cardiac preload for organ perfusion, resulting in normalization of pulmonary edema by day 2. PiCCO facilitates understanding of the mechanism of NPE, guiding the management of fluid balance and the choice of vasopressors in patients with life-threatening NPE.

Chronic hydrocephalus-induced changes in cerebral blood flow: mediation through cardiac effects.

Science.gov (United States)

Dombrowski, Stephen M; Schenk, Soren; Leichliter, Anna; Leibson, Zack; Fukamachi, Kiyotaka; Luciano, Mark G

2006-10-01

Decreased cerebral blood flow (CBF) in hydrocephalus is believed to be related to increased intracranial pressure (ICP), vascular compression as the result of enlarged ventricles, or impaired metabolic activity. Little attention has been given to the relationship between cardiac function and systemic blood flow in chronic hydrocephalus (CH). Using an experimental model of chronic obstructive hydrocephalus developed in our laboratory, we investigated the relationship between the duration and severity of hydrocephalus and cardiac output (CO), CBF, myocardial tissue perfusion (MTP), and peripheral blood flow (PBF). Blood flow measures were obtained using the microsphere injection method under controlled hemodynamic conditions in experimental CH (n=23) and surgical control (n=8) canines at baseline and at 2, 4, 8, 12, and 16 weeks. Cardiac output measures were made using the Swan-Ganz thermodilution method. Intracranial compliance (ICC) via cerebrospinal fluid (CSF) bolus removal and infusion, and oxygen delivery in CSF and prefrontal cortex (PFC) were also investigated. We observed an initial surgical effect relating to 30% CO reduction and approximately 50% decrease in CBF, MTP, and PBF in both groups 2 weeks postoperatively, which recovered in control animals but continued to decline further in CH animals at 16 weeks. Cerebral blood flow, which was positively correlated with CO (P=0.028), showed no significant relationship with either CSF volume or pressure. Decreased CBF correlated with oxygen deprivation in PFC (P=0.006). Cardiac output was inversely related with ventriculomegaly (P=0.019), but did not correlate with ICP. Decreased CO corresponded to increased ICC, as measured by CSF infusion (P=0.04). Our results suggest that CH may have more of an influence on CO and CBF in the chronic stage than in the early condition, which was dominated by surgical effect. The cause of this late deterioration of cardiac function in hydrocephalus is uncertain, but may reflect

Factors influencing the development of low output state in patients with right ventricular infarction

Energy Technology Data Exchange (ETDEWEB)

Goto, Yoichi; Kanno, Kazuji; Saito, Muneyasu; Haze, Kazuo; Sumiyoshi, Tetsuya; Fukami, Kenichi; Fujiwara, Yasushi; Hiramori, Katsuhiko; Ikeda, Masao [National Cardiovascular Center, Suita, Osaka (Japan)

1984-06-01

Right ventricular infarction is frequently accompanied by a low output state, but the factors influencing the development of this state remain unknown. To elucidate these factors, clinical findings, hemodynamic findings and left ventricular infarct size (Tl-score) calculated from thallium-201 myocardial scintigrams by a circumferential profile method were evaluated in 147 consecutive patients with acute transmural inferior myocardial infarction. They were divided into two groups: 44 patients with right ventricular involvement (RVI group) and 103 patients without right ventricular involvement (IMI group). A low cardiac output state was defined when the cardiac index was less than 2.2 L/min/M/sup 2/. There was a good correlation between Tl-score and any of peak value of serum creatine phosphokinase (CPKmax), total released CPK (CPKr) and left ventricular ejection fraction (LVEF) (r=o.66, 0.74 and -0.54, respectively), indicating the usefulness of Tl-score as an index of left ventricular damage. Compared to the IMI group, the RVI group showed a higher average of age (p < 0.01), lower systemic blood pressure (p < 0.01), higher right atrial pressure (p < 0.001) and lower cardiac index (p < 0.01). Furthermore, the incidence of a low output state (RVI group:47.7% vs IMI group:14.6%, p < 0.001) and mortality (25.0% vs 7.8%, p < 0.01) were higher in the RVI group. However, CPKmax, CPKr, LVEF and Tl-score, which were considered to reflect the severity of left ventricular damage, were not different between the two groups. Tl-score was inversely correlated with cardiac index in the RVI group (r=-0.49, p < 0.05), and with left ventricular stroke work index in the both groups (RVI group; r=-0.46, p < 0.01, IMI group; r=-0.64, p < 0.01).

A randomized controlled trial of levosimendan to reduce mortality in high-risk cardiac surgery patients (CHEETAH): Rationale and design.

Science.gov (United States)

Zangrillo, Alberto; Alvaro, Gabriele; Pisano, Antonio; Guarracino, Fabio; Lobreglio, Rosetta; Bradic, Nikola; Lembo, Rosalba; Gianni, Stefano; Calabrò, Maria Grazia; Likhvantsev, Valery; Grigoryev, Evgeny; Buscaglia, Giuseppe; Pala, Giovanni; Auci, Elisabetta; Amantea, Bruno; Monaco, Fabrizio; De Vuono, Giovanni; Corcione, Antonio; Galdieri, Nicola; Cariello, Claudia; Bove, Tiziana; Fominskiy, Evgeny; Auriemma, Stefano; Baiocchi, Massimo; Bianchi, Alessandro; Frontini, Mario; Paternoster, Gianluca; Sangalli, Fabio; Wang, Chew-Yin; Zucchetti, Maria Chiara; Biondi-Zoccai, Giuseppe; Gemma, Marco; Lipinski, Michael J; Lomivorotov, Vladimir V; Landoni, Giovanni

2016-07-01

Patients undergoing cardiac surgery are at risk of perioperative low cardiac output syndrome due to postoperative myocardial dysfunction. Myocardial dysfunction in patients undergoing cardiac surgery is a potential indication for the use of levosimendan, a calcium sensitizer with 3 beneficial cardiovascular effects (inotropic, vasodilatory, and anti-inflammatory), which appears effective in improving clinically relevant outcomes. Double-blind, placebo-controlled, multicenter randomized trial. Tertiary care hospitals. Cardiac surgery patients (n = 1,000) with postoperative myocardial dysfunction (defined as patients with intraaortic balloon pump and/or high-dose standard inotropic support) will be randomized to receive a continuous infusion of either levosimendan (0.05-0.2 μg/[kg min]) or placebo for 24-48 hours. The primary end point will be 30-day mortality. Secondary end points will be mortality at 1 year, time on mechanical ventilation, acute kidney injury, decision to stop the study drug due to adverse events or to start open-label levosimendan, and length of intensive care unit and hospital stay. We will test the hypothesis that levosimendan reduces 30-day mortality in cardiac surgery patients with postoperative myocardial dysfunction. This trial is planned to determine whether levosimendan could improve survival in patients with postoperative low cardiac output syndrome. The results of this double-blind, placebo-controlled randomized trial may provide important insights into the management of low cardiac output in cardiac surgery. Copyright © 2016 Elsevier Inc. All rights reserved.

Implanted near-infrared spectroscopy for cardiac monitoring

Science.gov (United States)

Bhunia, Sourav K.; Cinbis, Can

2011-02-01

Implanted Cardioverter Defibrillator (ICD) provides one of the most effective therapies for the prevention of sudden cardiac death, but also delivers some high voltage shocks inappropriately, causing morbidity and mortality. Implanted near-infrared spectroscopy (NIRS) may augment ICD arrhythmia detection by monitoring skeletal muscle perfusion. A two-wavelength, single-distance, continuous-wave implanted NIRS has been evaluated in-vivo. A weighted difference of the changes in attenuation at two wavelengths, across the isobestic point of the hemoglobin spectra, was taken to be the microvascular oxygenation trend indicator (O2 Index). Although the exact weight depends on the local vascular distribution and their oxygen levels, the hypothesis that a constant weight may be adequate for hemodynamic trending during short arrhythmic episodes, was tested. The sensor was implanted subcutaneously both on fresh tissue and inside scar tissue that formed around a pre-existing implant, in 3 animals each. Attenuations were recorded at 660 and 890 nm during normal sinus rhythm (NSR) and induced ventricular fibrillation (VF). The slope of the O2 Index over 10 seconds was computed for 7 NSR and 8 VF episodes in fresh and 13 NSR and 15 VF episodes in scar tissue pockets. The mean O2 Index slope was significantly different (p<0.0001) between NSR and VF rhythms for both the fresh and scar tissue pockets. Therefore implanted NIRS may be useful for preventing inappropriate detection of VF during electromagnetic interference, double counting of ECG T-wave as an R-wave, ICD lead failure, electrocardiographic aberrancy etc.

Dexmedetomidine decreases inhibitory but not excitatory neurotransmission to cardiac vagal neurons in the nucleus ambiguus.

Science.gov (United States)

Sharp, Douglas B; Wang, Xin; Mendelowitz, David

2014-07-29

Dexmedetomidine, an α2 adrenergic agonist, is a useful sedative but can also cause significant bradycardia. This decrease in heart rate may be due to decreased central sympathetic output as well as increased parasympathetic output from brainstem cardiac vagal neurons. In this study, using whole cell voltage clamp methodology, the actions of dexmedetomidine on excitatory glutamatergic and inhibitory GABAergic and glycinergic neurotransmission to parasympathetic cardiac vagal neurons in the rat nucleus ambiguus was determined. The results indicate that dexmedetomidine decreases both GABAergic and glycinergic inhibitory input to cardiac vagal neurons, with no significant effect on excitatory input. These results provide a mechanism for dexmedetomidine induced bradycardia and has implications for the management of this potentially harmful side effect. Copyright © 2014 Elsevier B.V. All rights reserved.

Fetal Cardiac Doppler Signal Processing Techniques: Challenges and Future Research Directions

Directory of Open Access Journals (Sweden)

Saeed Abdulrahman Alnuaimi

2017-12-01

Full Text Available The fetal Doppler Ultrasound (DUS is commonly used for monitoring fetal heart rate and can also be used for identifying the event timings of fetal cardiac valve motions. In early-stage fetuses, the detected Doppler signal suffers from noise and signal loss due to the fetal movements and changing fetal location during the measurement procedure. The fetal cardiac intervals, which can be estimated by measuring the fetal cardiac event timings, are the most important markers of fetal development and well-being. To advance DUS-based fetal monitoring methods, several powerful and well-advanced signal processing and machine learning methods have recently been developed. This review provides an overview of the existing techniques used in fetal cardiac activity monitoring and a comprehensive survey on fetal cardiac Doppler signal processing frameworks. The review is structured with a focus on their shortcomings and advantages, which helps in understanding fetal Doppler cardiogram signal processing methods and the related Doppler signal analysis procedures by providing valuable clinical information. Finally, a set of recommendations are suggested for future research directions and the use of fetal cardiac Doppler signal analysis, processing, and modeling to address the underlying challenges.

Characterization of Glutamatergic Neurons in the Rat Atrial Intrinsic Cardiac Ganglia that Project to the Cardiac Ventricular Wall

Science.gov (United States)

Wang, Ting; Miller, Kenneth E.

2016-01-01

The intrinsic cardiac nervous system modulates cardiac function by acting as an integration site for regulating autonomic efferent cardiac output. This intrinsic system is proposed to be composed of a short cardio-cardiac feedback control loop within the cardiac innervation hierarchy. For example, electrophysiological studies have postulated the presence of sensory neurons in intrinsic cardiac ganglia for regional cardiac control. There is still a knowledge gap, however, about the anatomical location and neurochemical phenotype of sensory neurons inside intrinsic cardiac ganglia. In the present study, rat intrinsic cardiac ganglia neurons were characterized neurochemically with immunohistochemistry using glutamatergic markers: vesicular glutamate transporters 1 and 2 (VGLUT1; VGLUT2), and glutaminase (GLS), the enzyme essential for glutamate production. Glutamatergic neurons (VGLUT1/VGLUT2/GLS) in the ICG that have axons to the ventricles were identified by retrograde tracing of wheat germ agglutinin-horseradish peroxidase (WGA-HRP) injected in the ventricular wall. Co-labeling of VGLUT1, VGLUT2, and GLS with the vesicular acetylcholine transporter (VAChT) was used to evaluate the relationship between post-ganglionic autonomic neurons and glutamatergic neurons. Sequential labeling of VGLUT1 and VGLUT2 in adjacent tissue sections was used to evaluate the co-localization of VGLUT1 and VGLUT2 in ICG neurons. Our studies yielded the following results: (1) intrinsic cardiac ganglia contain glutamatergic neurons with GLS for glutamate production and VGLUT1 and 2 for transport of glutamate into synaptic vesicles; (2) atrial intrinsic cardiac ganglia contain neurons that project to ventricle walls and these neurons are glutamatergic; (3) many glutamatergic ICG neurons also were cholinergic, expressing VAChT. (4) VGLUT1 and VGLUT2 co-localization occurred in ICG neurons with variation of their protein expression level. Investigation of both glutamatergic and cholinergic ICG

Bayesian Sensitivity Analysis of a Cardiac Cell Model Using a Gaussian Process Emulator

Science.gov (United States)

Chang, Eugene T Y; Strong, Mark; Clayton, Richard H

2015-01-01

Models of electrical activity in cardiac cells have become important research tools as they can provide a quantitative description of detailed and integrative physiology. However, cardiac cell models have many parameters, and how uncertainties in these parameters affect the model output is difficult to assess without undertaking large numbers of model runs. In this study we show that a surrogate statistical model of a cardiac cell model (the Luo-Rudy 1991 model) can be built using Gaussian process (GP) emulators. Using this approach we examined how eight outputs describing the action potential shape and action potential duration restitution depend on six inputs, which we selected to be the maximum conductances in the Luo-Rudy 1991 model. We found that the GP emulators could be fitted to a small number of model runs, and behaved as would be expected based on the underlying physiology that the model represents. We have shown that an emulator approach is a powerful tool for uncertainty and sensitivity analysis in cardiac cell models. PMID:26114610

Hemodynamic monitoring and management in patients undergoing high risk surgery: a survey among North American and European anesthesiologists.

Science.gov (United States)

Cannesson, Maxime; Pestel, Gunther; Ricks, Cameron; Hoeft, Andreas; Perel, Azriel

2011-08-15

Several studies have demonstrated that perioperative hemodynamic optimization has the ability to improve postoperative outcome in high-risk surgical patients. All of these studies aimed at optimizing cardiac output and/or oxygen delivery in the perioperative period. We conducted a survey with the American Society of Anesthesiologists (ASA) and the European Society of Anaesthesiology (ESA) to assess current hemodynamic management practices in patients undergoing high-risk surgery in Europe and in the United States. A survey including 33 specific questions was emailed to 2,500 randomly selected active members of the ASA and to active ESA members. Overall, 368 questionnaires were completed, 57.1% from ASA and 42.9% from ESA members. Cardiac output is monitored by only 34% of ASA and ESA respondents (P = 0.49) while central venous pressure is monitored by 73% of ASA respondents and 84% of ESA respondents (P < 0.01). Specifically, the pulmonary artery catheter is being used much more frequently in the US than in Europe in the setup of high-risk surgery (85.1% vs. 55.3% respectively, P < 0.001). Clinical experience, blood pressure, central venous pressure, and urine output are the most widely indicators of volume expansion. Finally, 86.5% of ASA respondents and 98.1% of ESA respondents believe that their current hemodynamic management could be improved. In conclusion, these results point to a considerable gap between the accumulating evidence about the benefits of perioperative hemodynamic optimization and the available technologies that may facilitate its clinical implementation, and clinical practices in both Europe and the United States.

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.

Neuromuscular blockade in cardiac surgery: An update for clinicians

Directory of Open Access Journals (Sweden)

Hemmerling Thomas

2008-01-01

Full Text Available There have been great advancements in cardiac surgery over the last two decades; the widespread use of off-pump aortocoronary bypass surgery, minimally invasive cardiac surgery, and robotic surgery have also changed the face of cardiac anaesthesia. The concept of "Fast-track anaesthesia" demands the use of nondepolarising neuromuscular blocking drugs with short duration of action, combining the ability to provide (if necessary sufficiently profound neuromuscular blockade during surgery and immediate re-establishment of normal neuromuscular transmission at the end of surgery. Postoperative residual muscle paralysis is one of the major hurdles for immediate or early extubation after cardiac surgery. Nondepolarising neuromuscular blocking drugs for cardiac surgery should therefore be easy to titrate, of rapid onset and short duration of action with a pathway of elimination independent from hepatic or renal dysfunction, and should equally not affect haemodynamic stability. The difference between repetitive bolus application and continuous infusion is outlined in this review, with the pharmacodynamic and pharmacokinetic characteristics of vecuronium, pancuronium, rocuronium, and cisatracurium. Kinemyography and acceleromyography are the most important currently used neuromuscular monitoring methods. Whereas monitoring at the adductor pollicis muscle is appropriate at the end of surgery, monitoring of the corrugator supercilii muscle better reflects neuromuscular blockade at more central, profound muscles, such as the diaphragm, larynx, or thoraco-abdominal muscles. In conclusion, cisatracurium or rocuronium is recommended for neuromuscular blockade in modern cardiac surgery.

Neonatal Hemodynamics: From Developmental Physiology to Comprehensive Monitoring

Directory of Open Access Journals (Sweden)

Sabine L. Vrancken

2018-04-01

Full Text Available Maintenance of neonatal circulatory homeostasis is a real challenge, due to the complex physiology during postnatal transition and the inherent immaturity of the cardiovascular system and other relevant organs. It is known that abnormal cardiovascular function during the neonatal period is associated with increased risk of severe morbidity and mortality. Understanding the functional and structural characteristics of the neonatal circulation is, therefore, essential, as therapeutic hemodynamic interventions should be based on the assumed underlying (pathophysiology. The clinical assessment of systemic blood flow (SBF by indirect parameters, such as blood pressure, capillary refill time, heart rate, urine output, and central-peripheral temperature difference is inaccurate. As blood pressure is no surrogate for SBF, information on cardiac output and systemic vascular resistance should be obtained in combination with an evaluation of end organ perfusion. Accurate and reliable hemodynamic monitoring systems are required to detect inadequate tissue perfusion and oxygenation at an early stage before this result in irreversible damage. Also, the hemodynamic response to the initiated treatment should be re-evaluated regularly as changes in cardiovascular function can occur quickly. New insights in the understanding of neonatal cardiovascular physiology are reviewed and several methods for current and future neonatal hemodynamic monitoring are discussed.

A Real-Time Health Monitoring System for Remote Cardiac Patients Using Smartphone and Wearable Sensors

Directory of Open Access Journals (Sweden)

Priyanka Kakria

2015-01-01

Full Text Available Online telemedicine systems are useful due to the possibility of timely and efficient healthcare services. These systems are based on advanced wireless and wearable sensor technologies. The rapid growth in technology has remarkably enhanced the scope of remote health monitoring systems. In this paper, a real-time heart monitoring system is developed considering the cost, ease of application, accuracy, and data security. The system is conceptualized to provide an interface between the doctor and the patients for two-way communication. The main purpose of this study is to facilitate the remote cardiac patients in getting latest healthcare services which might not be possible otherwise due to low doctor-to-patient ratio. The developed monitoring system is then evaluated for 40 individuals (aged between 18 and 66 years using wearable sensors while holding an Android device (i.e., smartphone under supervision of the experts. The performance analysis shows that the proposed system is reliable and helpful due to high speed. The analyses showed that the proposed system is convenient and reliable and ensures data security at low cost. In addition, the developed system is equipped to generate warning messages to the doctor and patient under critical circumstances.

A Real-Time Health Monitoring System for Remote Cardiac Patients Using Smartphone and Wearable Sensors.

Science.gov (United States)

Kakria, Priyanka; Tripathi, N K; Kitipawang, Peerapong

2015-01-01

Online telemedicine systems are useful due to the possibility of timely and efficient healthcare services. These systems are based on advanced wireless and wearable sensor technologies. The rapid growth in technology has remarkably enhanced the scope of remote health monitoring systems. In this paper, a real-time heart monitoring system is developed considering the cost, ease of application, accuracy, and data security. The system is conceptualized to provide an interface between the doctor and the patients for two-way communication. The main purpose of this study is to facilitate the remote cardiac patients in getting latest healthcare services which might not be possible otherwise due to low doctor-to-patient ratio. The developed monitoring system is then evaluated for 40 individuals (aged between 18 and 66 years) using wearable sensors while holding an Android device (i.e., smartphone under supervision of the experts). The performance analysis shows that the proposed system is reliable and helpful due to high speed. The analyses showed that the proposed system is convenient and reliable and ensures data security at low cost. In addition, the developed system is equipped to generate warning messages to the doctor and patient under critical circumstances.

G16R single nucleotide polymorphism but not haplotypes of the ß2-adrenergic receptor gene alters cardiac output in humans

DEFF Research Database (Denmark)

Rokamp, Kim Z; Staalsø, Jonatan M; Gartmann, Martin

2013-01-01

Variation in genes encoding the ß2-adrenergic receptor (ADRB2) and angiotensin-converting enzyme (ACE) may influence Q¿ (cardiac output). The 46G>A (G16R) SNP (single nucleotide polymorphism) has been associated with ß2-mediated vasodilation, but the effect of ADRB2 haplotypes on Q¿ has not been...... studied. Five SNPs within ADRB2 (46G>A, 79C>G, 491C>T, 523C>A and 1053G>C by a pairwise tagging principle) and the I/D (insertion/deletion) polymorphism in ACE were genotyped in 143 subjects. Cardiovascular variables were evaluated by the Model flow method at rest and during incremental cycling exercise...... V¿O2 (oxygen uptake) in G16G subjects, but the increase was 0.5 (0.0-0.9) l/min lower in Arg16 carriers (P=0.035). A similar effect size was observed for the Arg16 haplotypes ACCCG and ACCCC. No interaction was found between ADRB2 and ACE polymorphisms. During exercise, the increase in Q¿ was 0...

The use of an improved technique to reduce the variability of output voltage in real-time Fibre Bragg Grating based monitoring system

Science.gov (United States)

Vorathin, E.; Hafizi, Z. M.; Che Ghani, S. A.; Lim, K. S.; Aizzuddin, A. M.

2017-10-01

Fibre Bragg Grating (FBG) sensors have been widely utilized in the structural health monitoring (SHM) of structures. However, one of the main challenges of FBGs is the existence of inconsistency in output voltage during wavelength intensity demodulation utilizing photodetector (PD) to convert the light signal into digital voltage readings. Thus, the designation of this experimental work is to develop a robust FBG real-time monitoring system with the benefit of MATLAB graphical user interface (GUI) and voltage normalization algorithm to scale down the voltage inconsistency. Low-cost edge filter interrogation system has been practiced in the experimentation and splitter optical component is make use to reduce the intensity of the high power light source that leads to the formation of noise due to unwanted reflected wavelengths. The results revealed that with the advancement of the proposed monitoring system, the sensitivity of the FBG has been increased from 2.4 mV/N to 3.8 mV/N across the range of 50 N. The redundancy in output voltage variation data points has been reduced from 26 data/minute to 17 data/minute. The accuracy of the FBG in detecting the load induced falls in the acceptable range of total average error which is 1.38 %.

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�

Consumer sleep monitors: is there a baby in the bathwater?

Science.gov (United States)

Russo, Kathryn; Goparaju, Balaji; Bianchi, Matt T

2015-01-01

The rapid expansion of consumer sleep devices is outpacing the validation data necessary to assess the potential use of these devices in clinical and research settings. Common sleep monitoring devices utilize a variety of sensors to track movement as well as cardiac and respiratory physiology. The variety of sensors and user-specific factors offer the potential, at least theoretically, for clinically relevant information. We describe the current challenges for interpretation of consumer sleep monitoring data, since the devices are mainly used in non-medical contexts (consumer use) although medically-definable sleep disorders may commonly occur in this setting. A framework for addressing questions of how certain devices might be useful is offered. We suggest that multistage validation efforts are crucially needed, from the level of sensor data and algorithm output, to extrapolations beyond healthy adults and into other populations and real-world environments.

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

A portable cadmium telluride multidetector probe for cardiac function monitoring

Energy Technology Data Exchange (ETDEWEB)

Arntz, Y.; Chambron, J.; Dumitresco, B.; Eclancher, B. E-mail: eclan@alsace.u-strasbg.fr; Prat, V

1999-06-01

A new nuclear stethoscope based on a matrix of small CdTe semiconductor detectors has been developed for studying the cardiac performance by gamma ventriculography at the equilibrium, in rest and stress conditions, in the early and recovery phases of the coronary disease and to follow the long-term therapy. The light-weight probe consists of an array of 64 detectors 5x5x2 mm grouped in 16 independent units in a lead shielded aluminum box including 16 preamplifiers. The probe is connected to an electronic box containing DC power supply, 16 channel amplifiers, discriminators and counters, two analog-triggering ECG channels, and interface to a PC. The left ventricle activity is, preferentially, detected by using a low-resolution matching convergent collimator. A physical evaluation of the probe has been performed, both with static tests and dynamically with a hydraulic home-built model of beating heart ventricle paced by a rhythm simulator. The sum of the 16 detectors activity provided a radiocardiogram (RCG) which well depicted the filling and ejection of the cardiac beats, allowing to compare the clinically relevant parameters of the cardiac performance, proportional variables of the stroke volume (SV), ejection fraction (EF) and ventricular flow-rate with the known absolute values programmed on the model. The portable system is now in operation for clinical assessment of cardiac patients.

A portable cadmium telluride multidetector probe for cardiac function monitoring

International Nuclear Information System (INIS)

Arntz, Y.; Chambron, J.; Dumitresco, B.; Eclancher, B.; Prat, V.

1999-01-01

A new nuclear stethoscope based on a matrix of small CdTe semiconductor detectors has been developed for studying the cardiac performance by gamma ventriculography at the equilibrium, in rest and stress conditions, in the early and recovery phases of the coronary disease and to follow the long-term therapy. The light-weight probe consists of an array of 64 detectors 5x5x2 mm grouped in 16 independent units in a lead shielded aluminum box including 16 preamplifiers. The probe is connected to an electronic box containing DC power supply, 16 channel amplifiers, discriminators and counters, two analog-triggering ECG channels, and interface to a PC. The left ventricle activity is, preferentially, detected by using a low-resolution matching convergent collimator. A physical evaluation of the probe has been performed, both with static tests and dynamically with a hydraulic home-built model of beating heart ventricle paced by a rhythm simulator. The sum of the 16 detectors activity provided a radiocardiogram (RCG) which well depicted the filling and ejection of the cardiac beats, allowing to compare the clinically relevant parameters of the cardiac performance, proportional variables of the stroke volume (SV), ejection fraction (EF) and ventricular flow-rate with the known absolute values programmed on the model. The portable system is now in operation for clinical assessment of cardiac patients

Measurement of cardiac output in children by pressure-recording analytical method.

Science.gov (United States)

Urbano, Javier; López, Jorge; González, Rafael; Solana, María José; Fernández, Sarah N; Bellón, José M; López-Herce, Jesús

2015-02-01

We evaluated two pressure-recording analytical method (PRAM) software versions (v.1 and v.2) to measure cardiac index (CI) in hemodynamically stable critically ill children and investigate factors that influence PRAM values. The working hypothesis was that PRAM CI measurements would stay within normal limits in hemodynamically stable patients. Ninety-five CI PRAM measurements were analyzed in 47 patients aged 1-168 months. Mean CI was 4.1 ± 1.4 L/min/m(2) (range 2.0-7.0). CI was outside limits defined as normal (3-5 L/min/m(2)) in 53.7% of measurements (47.8% with software v.1 and 69.2% with software v.2, p = 0.062). Moreover, 14.7% of measurements were below 2.5 L/min/m(2), and 13.6% were above 6 L/min/m(2). CI was significantly lower in patients with a clearly visible dicrotic notch than in those without (3.7 vs. 4.6 L/min/m(2), p = 0.004) and in children with a radial arterial catheter (3.5 L/min/m(2)) than in those with a brachial (4.4 L/min/m(2), p = 0.021) or femoral catheter (4.7 L/min/m(2), p = 0.005). By contrast, CI was significantly higher in children under 12 months (4.2 vs. 3.6 L/min/m(2), p = 0.034) and weighing under 10 kg (4.2 vs. 3.6 L/min/m(2), p = 0.026). No significant differences were observed between cardiac surgery patients and the rest of children. A high percentage of CI measurements registered by PRAM were outside normal limits in hemodynamically stable, critically ill children. CI measured by PRAM may be influenced by the age, weight, location of catheter, and presence of a dicrotic notch.

Use of transesophageal Doppler ultrasonography in ventilated pediatric patients: derivation of cardiac output.

Science.gov (United States)

Tibby, S M; Hatherill, M; Murdoch, I A

2000-06-01

To ascertain if cardiac output (CO) could be derived from blood flow velocity measured in the descending aorta of ventilated children by transesophageal Doppler ultrasonography (TED) without the need for direct aortic cross sectional area measurement, and to evaluate the ability of TED to follow changes in CO when compared with femoral artery thermodilution. Prospective, comparison study. A 16-bed pediatric intensive care unit of a university hospital. A total of 100 ventilated infants and children aged 4 days to 18 yrs (median age, 27 months). Diagnoses included postcardiac surgery (n = 58), sepsis/multiple organ failure (n = 32), respiratory disease (n = 5), and other (n = 5). A total of 55 patients were receiving inotropes or vasodilators. When patients were hemodynamically stable, a TED probe was placed into the distal esophagus to obtain optimal signal, and minute distance (MD) was recorded. Five consecutive MD measurements were made concurrently with five femoral artery thermodilution measurements, and the concurrent measurements were averaged. CO was then manipulated by fluid administration or inotrope adjustment, and the readings were repeated. Femoral artery thermodilution CO ranged from 0.32 to 9.19 L/min, (median, 2.46 L/min), and encompassed a wide range of high and low flow states. Theoretical consideration revealed the optimal TED estimate for CO to be (MD x patient height2 x 10(-7)). Linear regression analysis yielded a power function model such that: estimated CO = 1.158 x (MD x height2 x 10(-7))(0.785), r2 = 0.879, standard error of the estimate = 0.266. Inclusion of a correction factor for potential changes in aortic cross-sectional area with hypo- and hypertension did not appreciably improve the predictive value of the model. MD was able to follow percentage changes in CO, giving a mean bias of 0.87% (95% confidence interval -0.85% to 2.59%), and limits of agreement of +/- 16.82%. The median coefficient of variation for MD was 3.3%. TED provides

National Cardiac Device Surveillance Program Database

Data.gov (United States)

Department of Veterans Affairs — The National Cardiac Device Surveillance Program Database supports the Eastern Pacemaker Surveillance Center (EPSC) staff in its function of monitoring some 11,000...

Cardiac function and myocardial perfusion immediately following maximal treadmill exercise inside the MRI room

Directory of Open Access Journals (Sweden)

Ballinger Michelle R

2008-01-01

Full Text Available Abstract Treadmill exercise stress testing is an essential tool in the prevention, detection, and treatment of a broad spectrum of cardiovascular disease. After maximal exercise, cardiac images at peak stress are typically acquired using nuclear scintigraphy or echocardiography, both of which have inherent limitations. Although CMR offers superior image quality, the lack of MRI-compatible exercise and monitoring equipment has prevented the realization of treadmill exercise CMR. It is critical to commence imaging as quickly as possible after exercise to capture exercise-induced cardiac wall motion abnormalities. We modified a commercial treadmill such that it could be safely positioned inside the MRI room to minimize the distance between the treadmill and the scan table. We optimized the treadmill exercise CMR protocol in 20 healthy volunteers and successfully imaged cardiac function and myocardial perfusion at peak stress, followed by viability imaging at rest. Imaging commenced an average of 30 seconds after maximal exercise. Real-time cine of seven slices with no breath-hold and no ECG-gating was completed within 45 seconds of exercise, immediately followed by stress perfusion imaging of three short-axis slices which showed an average time to peak enhancement within 57 seconds of exercise. We observed a 3.1-fold increase in cardiac output and a myocardial perfusion reserve index of 1.9, which agree with reported values for healthy subjects at peak stress. This study successfully demonstrates in-room treadmill exercise CMR in healthy volunteers, but confirmation of feasibility in patients with heart disease is still needed.

Plant-derived cardiac glycosides: Role in heart ailments and cancer management.

Science.gov (United States)

Patel, Seema

2016-12-01

Cardiac glycosides, the cardiotonic steroids such as digitalis have been in use as heart ailment remedy since ages. They manipulate the renin-angiotensin axis to improve cardiac output. However; their safety and efficacy have come under scrutiny in recent times, as poisoning and accidental mortalities have been observed. In order to better understand and exploit them as cardiac ionotropes, studies are being pursued using different cardiac glycosides such as digitoxin, digoxin, ouabain, oleandrin etc. Several cardiac glycosides as peruvoside have shown promise in cancer control, especially ovary cancer and leukemia. Functional variability of these glycosides has revealed that not all cardiac glycosides are alike. Apart from their specific affinity to sodium-potassium ATPase, their therapeutic dosage and behavior in poly-morbidity conditions needs to be considered. This review presents a concise account of the key findings in recent years with adequate elaboration of the mechanisms. This compilation is expected to contribute towards management of cardiac, cancer, even viral ailments. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

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.

Cardiac monitoring for detection of atrial fibrillation after TIA: A systematic review and meta-analysis.

Science.gov (United States)

Korompoki, Eleni; Del Giudice, Angela; Hillmann, Steffi; Malzahn, Uwe; Gladstone, David J; Heuschmann, Peter; Veltkamp, Roland

2017-01-01

Background and purpose The detection rate of atrial fibrillation has not been studied specifically in transient ischemic attack (TIA) patients although extrapolation from ischemic stroke may be inadequate. We conducted a systematic review and meta-analysis to determine the rate of newly diagnosed atrial fibrillation using different methods of ECG monitoring in TIA. Methods A comprehensive literature search was performed following a pre-specified protocol the PRISMA statement. Prospective observational studies and randomized controlled trials were considered that included TIA patients who underwent cardiac monitoring for >12 h. Primary outcome was frequency of detection of atrial fibrillation ≥30 s. Analyses of subgroups and of duration and type of monitoring were performed. Results Seventeen studies enrolling 1163 patients were included. The pooled atrial fibrillation detection rate for all methods was 4% (95% CI: 2-7%). Yield of monitoring was higher in selected (higher age, more extensive testing for arrhythmias before enrolment, or presumed cardioembolic/cryptogenic cause) than in unselected cohorts (7% vs 3%). Pooled mean atrial fibrillation detection rates rose with duration of monitoring: 4% (24 h), 5% (24 h to 7 days) and 6% (>7 days), respectively. Yield of non-invasive was significantly lower than that of invasive monitoring (4% vs. 11%). Significant heterogeneity was observed among studies (I 2 =60.61%). Conclusion This first meta-analysis of atrial fibrillation detection in TIA patients finds a lower atrial fibrillation detection rate in TIA than reported for IS and TIA cohorts in previous meta-analyses. Prospective studies are needed to determine actual prevalence of atrial fibrillation and optimal diagnostic procedure for atrial fibrillation detection in TIA.

Sudden cardiac arrest as a rare presentation of myxedema coma: case report.

Science.gov (United States)

Salhan, Divya; Sapkota, Deepak; Verma, Prakash; Kandel, Saroj; Abdulfattah, Omar; Lixon, Antony; Zwenge, Deribe; Schmidt, Frances

2017-01-01

Myxedema coma is a decompensated hypothyroidism which occurs due to long-standing, undiagnosed, or untreated hypothyroidism. Untreated hypothyroidism is known to affect almost all organs including the heart. It is associated with a decrease in cardiac output, stroke volume due to decreased myocardial contractility, and an increase in systemic vascular resistance. It can cause cardiac arrhythmias and the most commonly seen conduction abnormalities are sinus bradycardia, heart block, ventricular tachycardia, and torsade de pointes. The authors report a case of an elderly man who presented with sudden cardiac arrest and myxedema coma and who was successfully revived.

Analysis of output trends from Varian 2100C/D and 600C/D accelerators

International Nuclear Information System (INIS)

Grattan, M W D; Hounsell, A R

2011-01-01

Analysis of Varian linear accelerator output trends is reported. Two groups, consisting of four matched Varian 2100C/D and four matched Varian 600C/D accelerators, with different designs of monitor chamber, have been investigated and the data acquired from regular calibrated ion chamber/electrometer measurements of the output performance of the eight accelerators analysed. The trend of machine output with time, having removed the effect of adjusting the monitor chamber response, was compared on a monthly and annual basis for monitor chambers with ages ranging between 1 year and 7 years. The results indicate that the response is generally consistent within each set of accelerators with different monitor chamber designs. Those used in a Varian 600C/D machine result in a reduction in measured output over time, with an average monthly reduction of 0.35 ± 0.09% over the course of the first 4 years of use. The chambers used in a 2100C/D accelerator result in an increase in measured output over time, with an average monthly increase of 0.26 ± 0.09% over the course of the first 4 years of use. The output increase then reduces towards the end of this period of time, with the average monthly change falling to -0.03 ± 0.02% for the following 3 years. The output response trend was similar for all clinical energies used on the 2100C/D accelerators--6, 15 MV x-ray beams, and 4, 6, 9, 12, 16 and 20 MeV electron beams. By tracking these changes it has been possible to predict the response over time to allow appropriate adjustments in monitor chamber response to maintain a measured accelerator output within tolerance and give confidence in performance. It has also provided data to indicate the need for planned preventative intervention and indicate if the monitor chamber response is behaving as expected. (note)

Coi-wiz: An interactive computer wizard for analyzing cardiac optical signals.

Science.gov (United States)

Yuan, Xiaojing; Uyanik, Ilyas; Situ, Ning; Xi, Yutao; Cheng, Jie

2009-01-01

A number of revolutionary techniques have been developed for cardiac electrophysiology research to better study the various arrhythmia mechanisms that can enhance ablating strategies for cardiac arrhythmias. Once the three-dimensional high resolution cardiac optical imaging data is acquired, it is time consuming to manually go through them and try to identify the patterns associated with various arrhythmia symptoms. In this paper, we present an interactive computer wizard that helps cardiac electrophysiology researchers to visualize and analyze the high resolution cardiac optical imaging data. The wizard provides a file interface that accommodates different file formats. A series of analysis algorithms output waveforms, activation and action potential maps after spatial and temporal filtering, velocity field and heterogeneity measure. The interactive GUI allows the researcher to identify the region of interest in both the spatial and temporal domain, thus enabling them to study different heart chamber at their choice.

Influence of water immersion, water gymnastics and swimming on cardiac output in patients with heart failure.

Science.gov (United States)

Schmid, Jean-Paul; Noveanu, Markus; Morger, Cyrill; Gaillet, Raymond; Capoferri, Mauro; Anderegg, Matthias; Saner, Hugo

2007-06-01

Whole-body water immersion leads to a significant shift of blood from the periphery to the intrathoracic circulation, followed by an increase in central venous pressure and heart volume. In patients with severely reduced left ventricular function, this hydrostatically induced volume shift might overstrain the cardiovascular adaptive mechanisms and lead to cardiac decompensation. To assess the haemodynamic response to water immersion, gymnastics and swimming in patients with chronic heart failure (CHF). 10 patients with compensated CHF (62.9 (6.3) years, ejection fraction 31.5% (4.1%), peak oxygen consumption (Vo(2)) 19.4 (2.8) ml/kg/min), 10 patients with coronary artery disease (CAD) but preserved left ventricular function (57.2 (5.6) years, ejection fraction 63.9% (5.5%), peak Vo(2) 28 (6.3) ml/kg/min), and 10 healthy controls (32.8 (7.2) years, peak Vo(2) 45.6 (6) ml/kg/min) were examined. Haemodynamic response to thermoneutral (32 degrees C) water immersion and exercise was measured using a non-invasive foreign gas rebreathing method during stepwise water immersion, water gymnastics and swimming. Water immersion up to the chest increased cardiac index by 19% in controls, by 21% in patients with CAD and by 16% in patients with CHF. Although some patients with CHF showed a decrease of stroke volume during immersion, all subjects were able to increase cardiac index (by 87% in healthy subjects, by 77% in patients with CAD and by 53% in patients with CHF). Vo(2) during swimming was 9.7 (3.3) ml/kg/min in patients with CHF, 12.4 (3.5) ml/kg/min in patients with CAD and 13.9 (4) ml/kg/min in controls. Patients with severely reduced left ventricular function but stable clinical conditions and a minimal peak Vo(2) of at least 15 ml/kg/min during a symptom-limited exercise stress test tolerate water immersion and swimming in thermoneutral water well. Although cardiac index and Vo(2) are lower than in patients with CAD with preserved left ventricular function and controls

Magnetic resonance imaging of implantable cardiac rhythm devices at 3.0 tesla.

Science.gov (United States)

Gimbel, J Rod

2008-07-01

A relaxation of the prohibition of scanning cardiac rhythm device patients is underway, largely because of the growing experience of safe scanning events at 1.5T. Magnetic resonance imaging (MRI) at 3T is becoming more common and may pose a different risk profile and outcome of MRI of cardiac device patients. No restrictions were placed on pacemaker dependency, region scanned, device type, or manufacturer. Sixteen scans at 3T were performed with an electrophysiologist present on 14 patients with a variety of devices from various manufacturers. An "MRI-S" strategy was used. Multimodal monitoring was required. Device interrogation was performed prior to, immediately after, and 1-3 months after the MRI. For nonpacemaker-dependent device patients, attempts were made to turn all device features off (with OOO programming the goal) conceptually rendering the device "invisible." In pacemaker-dependent patients, the device was programmed to asynchronous mode at highest output for the duration of the scan with the goal of rendering the device conceptually "invulnerable" to MRI effects. The specific absorption rate (SAR) was limited to 2W/kg. All patients were successfully scanned. No arrhythmias were noted. No significant change in the programmed parameters, pacing thresholds, sensing, impedance, or battery parameters was noted. The insertable loop recorder (ILR) recorded prolonged artifactual asystole during MRI. One patient noted chest burning during the scan. Device patients may undergo carefully tailored 3T MRI scans when pre-MRI reprogramming of the device occurs in conjunction with extensive monitoring, supervision, and follow-up.

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...... be rescued by overexpression of wild-type MAp44. Our observations provide evidence that immune molecules are centrally involved in the orchestration of cardiac tissue development....

Near Infrared Spectroscopy during pediatric cardiac surgery: errors and pitfalls.

Science.gov (United States)

Durandy, Y; Rubatti, M; Couturier, R

2011-09-01

As a result of improvements in early outcomes, long-term neurologicalal outcomes are becoming a major issue in pediatric cardiac surgery. The mechanisms of brain injury are numerous, but a vast majority of injuries are impervious to therapy and only a few are modifiable. The quality of perfusion during cardiac surgery is a modifiable factor and cerebral monitoring during bypass is the way to assess the quality of intra-operative cerebral perfusion. Near infrared spectroscopy (NIRS), as a diagnostic tool, has gained in popularity within the perfusion community. However, NIRS is becoming the standard of care before its scientific validation. This manuscript relates four clinical cases, demonstrating the limitations of NIRS monitoring during pediatric cardiac surgery as well as uncertainties about the interpretation of the recorded values. The clinical relevance of cerebral oxymetry is needed before the use of NIRS as a decision making tool. Multimodal brain monitoring with NIRS, trans-cranial Doppler and electroencephalogram are currently under way in several pediatric centers. The benefit of this time-consuming and expensive monitoring system has yet to be demonstrated.

Trends in Cardiac Pacemaker Batteries

Directory of Open Access Journals (Sweden)

Venkateswara Sarma Mallela

2004-10-01

Full Text Available Batteries used in Implantable cardiac pacemakers-present unique challenges to their developers and manufacturers in terms of high levels of safety and reliability. In addition, the batteries must have longevity to avoid frequent replacements. Technological advances in leads/electrodes have reduced energy requirements by two orders of magnitude. Micro-electronics advances sharply reduce internal current drain concurrently decreasing size and increasing functionality, reliability, and longevity. It is reported that about 600,000 pacemakers are implanted each year worldwide and the total number of people with various types of implanted pacemaker has already crossed 3 million. A cardiac pacemaker uses half of its battery power for cardiac stimulation and the other half for housekeeping tasks such as monitoring and data logging. The first implanted cardiac pacemaker used nickel-cadmium rechargeable battery, later on zinc-mercury battery was developed and used which lasted for over 2 years. Lithium iodine battery invented and used by Wilson Greatbatch and his team in 1972 made the real impact to implantable cardiac pacemakers. This battery lasts for about 10 years and even today is the power source for many manufacturers of cardiac pacemakers. This paper briefly reviews various developments of battery technologies since the inception of cardiac pacemaker and presents the alternative to lithium iodine battery for the near future.

Perioperative utility of goal-directed therapy in high-risk cardiac patients undergoing coronary artery bypass grafting: “A clinical outcome and biomarker-based study”

Directory of Open Access Journals (Sweden)

Poonam Malhotra Kapoor

2016-01-01

Full Text Available Goal-directed therapy (GDT encompasses guidance of intravenous (IV fluid and vasopressor/inotropic therapy by cardiac output or similar parameters to help in early recognition and management of high-risk cardiac surgical patients. With the aim of establishing the utility of perioperative GDT using robust clinical and biochemical outcomes, we conducted the present study. This multicenter randomized controlled study included 130 patients of either sex, with European system for cardiac operative risk evaluation ≥3 undergoing coronary artery bypass grafting on cardiopulmonary bypass. The patients were randomly divided into the control and GDT group. All the participants received standardized care; arterial pressure monitored through radial artery, central venous pressure (CVP through a triple lumen in the right internal jugular vein, electrocardiogram, oxygen saturation, temperature, urine output per hour, and frequent arterial blood gas (ABG analysis. In addition, cardiac index (CI monitoring using FloTrac™ and continuous central venous oxygen saturation (ScVO2 using PreSep™ were used in patients in the GDT group. Our aim was to maintain the CI at 2.5–4.2 L/min/m2, stroke volume index 30–65 ml/beat/m2, systemic vascular resistance index 1500–2500 dynes/s/cm5/m2, oxygen delivery index 450–600 ml/min/m2, continuous ScVO2 >70%, and stroke volume variation 30%, and urine output >1 ml/kg/h. The aims were achieved by altering the administration of IV fluids and doses of inotropes or vasodilators. The data of sixty patients in each group were analyzed in view of ten exclusions. The average duration of ventilation (19.89 ± 3.96 vs. 18.05 ± 4.53 h, P = 0.025, hospital stay (7.94 ± 1.64 vs. 7.17 ± 1.93 days, P = 0.025, and Intensive Care Unit (ICU stay (3.74 ± 0.59 vs. 3.41 ± 0.75 days, P = 0.012 was significantly less in the GDT group, compared to the control group. The extra volume added and the number of inotropic dose adjustments were

Pattern of perioperative cardiac arrests at University of Maiduguri Teaching Hospital.

Science.gov (United States)

Kwari, Y D; Bello, M R; Eni, U E

2010-01-01

Perioperative cardiac arrests and death on the table represent the most serious complications of surgery and anaesthesia. This paper was designed to study their pattern, causes and outcomes following cardiopulmonary resuscitation (CPR) and intensive care unit (ICU) management in our institution. Three year retrospective review of perioperative cardiac arrests and death on operating table following surgical procedure under anaesthesia. For each cardiac arrest or death on the table the sequence of events leading to the arrest was evaluated using case notes, anaesthetic chart and ICU records. Study variables which include demographic data, ASA score, anaesthetic technique, causes and outcome were analysed and discussed. Fourteen perioperative cardiac arrests were encountered following 4051 anaesthetics administered over the three year study period. Twelve out of the fourteen cardiac arrests occurred following general anaesthesia, while the remaining two occurred following spinal anaesthesia. There was no cardiac arrest following local anaesthesia. Children suffered more cardiac arrest than adults. ASA class III and IV risk status suffered more arrests than ASA I and II. Hypoxia from airway problems was the commonest cause of cardiac arrest followed by septic shock. Monitoring with pulse oximeter was done in only 4 out of the 14 cardiac arrests. Only 2 (14%) out of 14 cardiac arrests recovered to home discharge, one of them with significant neurological deficit. Majority of arrests were due to hypoxia from airway problems that were not detected early There is need to improve on patient monitoring, knowledge of CPR and intensive care so as to improve the outcome of perioperative cardiac arrest.

Application of transpulmonary thermodilution monitoring (PiCCO) in patient with neurogenic pulmonary edema and acute obstructive hydrocephalus due to a central neurocytoma: A case report

OpenAIRE

Ryoichi Iwata; Kunikazu Yoshimura; Yoko Fujita; Tatsuo Uesaka; Hideyuki Oshige; Akio Asai

2017-01-01

Neurogenic pulmonary edema (NPE) is an acute life-threatening complication associated with many forms of central nervous system injury. Its pathophysiology is still debated. We report a patient with acute obstructive hydrocephalus due to a central neurocytoma who also had NPE, for which serial transpulmonary thermodilution monitoring (PiCCO) was performed. Insertion of the PiCCO, which provides information about the patient's cardiac output, preload status and amount of lung water, revealed a...

Cerebral Oximetry in Cardiac Surgery

Directory of Open Access Journals (Sweden)

A. N. Shepelyuk

2012-01-01

Full Text Available Based on the data of numerous current references, the review describes different neuromonitoring methods during cardiac surgery under extracorporeal circulation. It shows that it is important and necessary to make neuromonitoring for the early diagnosis and prevention of neurological complications after cardiac surgery. Particular attention is given to cerebral oximetry; the possibilities and advantages of this technique are described. Correction of cerebral oximetric values is shown to improve survival rates and to reduce the incidence of postoperative complications. Lack of cerebral oximetry monitoring denudes a clinician of important information and possibilities to optimize patient status and to prevent potentially menacing complications, which allows one to conclude that it is necessary to use cerebral oximetry procedures within neu-romonitoring in cardiac surgery. Key words: extracorporeal circulation, cerebral oximetry, neurological dysfunction, cerebral oxygenation.

Acute cardiac support with intravenous milrinone promotes recovery from early brain injury in a murine model of severe subarachnoid haemorrhage.

Science.gov (United States)

Mutoh, Tomoko; Mutoh, Tatsushi; Nakamura, Kazuhiro; Yamamoto, Yukiko; Tsuru, Yoshiharu; Tsubone, Hirokazu; Ishikawa, Tatsuya; Taki, Yasuyuki

2017-04-01

Early brain injury/ischaemia (EBI) is a serious complication early after subarachnoid haemorrhage (SAH) that contributes to development of delayed cerebral ischaemia (DCI). This study aimed to determine the role of inotropic cardiac support using milrinone (MIL) on restoring acute cerebral hypoperfusion attributable to EBI and improving outcomes after experimental SAH. Forty-three male C57BL/6 mice were assigned to either sham surgery (SAH-sham), SAH induced by endovascular perforation plus postconditioning with 2% isoflurane (Control), or SAH plus isoflurane combined with MIL with and without hypoxia-inducible factor inhibitor (HIF-I) pretreatment. Cardiac output (CO) during intravenous MIL infusion (0.25-0.75 μg/kg/min) between 1.5 and 2.5 hours after SAH induction was monitored with Doppler echocardiography. Magnetic resonance imaging (MRI)-continuous arterial spin labelling was used for quantitative cerebral blood flow (CBF) measurements. Neurobehavioral function was assessed daily by neurological score and open field test. DCI was analyzed 3 days later by determining infarction on MRI. Mild reduction of cardiac output (CO) and global cerebral blood flow (CBF) depression were notable early after SAH. MIL increased CO in a dose-dependent manner (P<.001), which was accompanied by improved hypoperfusion, incidence of DCI and functional recovery than Control (P<.05). The neuroprotective effects afforded by MIL or Control were attenuated by hypoxia-inducible factor (HIF) inhibition (P<.05). These results suggest that MIL improves acute hypoperfusion by its inotropic effect, leading to neurobehavioral improvement in mice after severe SAH, in which HIF may be acting as a critical mediator. © 2017 John Wiley & Sons Australia, Ltd.

Results of plasma N-terminal pro B-type natriuretic peptide and cardiac troponin monitoring in GIST patients do not support the existence of imatinib-induced cardiotoxicity

NARCIS (Netherlands)

Perik, P. J.; Rikhof, B.; de Jong, F. A.; Verweij, J.; Gietema, J. A.; van der Graaf, W. T. A.

Background: Recently, case reports of patients treated with imatinib (imatinib mesylate; Gleevec (R); Glvec (R)) indicated that this tyrosine kinase inhibitor may induce cardiomyopathy. Consequently, careful cardiac monitoring was advocated for clinical studies. The purpose of this study was to

A unique case of pulmonary artery catheter bleeding from the oximetry connection port

Directory of Open Access Journals (Sweden)

Suman Rajagopalan

2014-12-01

Full Text Available Pulmonary artery catheter is an invasive monitor usually placed in high-risk cardiac surgical patients to optimize the cardiac functions. We present this case of blood oozing from the oximetry connection port of the pulmonary artery catheter that resulted in the inability to monitor continuous cardiac output requiring replacement of the catheter. The cause of this abnormal bleeding was later confirmed to be due to a manufacturing defect.

Usefulness of emergency ultrasound in nontraumatic cardiac arrest.

Science.gov (United States)

Volpicelli, Giovanni

2011-02-01

Treatment of nontraumatic cardiac arrest in the hospital setting depends on the recognition of heart rhythm and differential diagnosis of the underlying condition while maintaining a constant oxygenated blood flow by ventilation and chest compression. Diagnostic process relies only on patient's history, physical findings, and active electrocardiography. Ultrasound is not currently scheduled in the resuscitation guidelines. Nevertheless, the use of real-time ultrasonography during resuscitation has the potential to improve diagnostic accuracy and allows the physician a greater confidence in deciding aggressive life-saving therapeutic procedures. This article reviews the current opinions and literature about the use of emergency ultrasound during resuscitation of nontraumatic cardiac arrest. Cardiac and lung ultrasound have a great potential in identifying the reversible mechanical causes of pulseless electrical activity or asystole. Brief examination of the heart can even detect a real cardiac standstill regardless of electrical activity displayed on the monitor, which is a crucial prognostic indicator. Moreover, ultrasound can be useful to verify and monitor the tracheal tube placement. Limitation to the use of ultrasound is the need to minimize the no-flow intervals during mechanical cardiopulmonary resuscitation. However, real-time ultrasound can be successfully applied during brief pausing of chest compression and first pulse-check. Finally, lung sonographic examination targeted to the detection of signs of pulmonary congestion has the potential to allow hemodynamic noninvasive monitoring before and after mechanical cardiopulmonary maneuvers. Copyright © 2011 Elsevier Inc. All rights reserved.

Chronic fatigue syndrome: illness severity, sedentary lifestyle, blood volume and evidence of diminished cardiac function.

Science.gov (United States)

Hurwitz, Barry E; Coryell, Virginia T; Parker, Meela; Martin, Pedro; Laperriere, Arthur; Klimas, Nancy G; Sfakianakis, George N; Bilsker, Martin S

2009-10-19

The study examined whether deficits in cardiac output and blood volume in a CFS (chronic fatigue syndrome) cohort were present and linked to illness severity and sedentary lifestyle. Follow-up analyses assessed whether differences in cardiac output levels between CFS and control groups were corrected by controlling for cardiac contractility and TBV (total blood volume). The 146 participants were subdivided into two CFS groups based on symptom severity data, severe (n=30) and non-severe (n=26), and two healthy non-CFS control groups based on physical activity, sedentary (n=58) and non-sedentary (n=32). Controls were matched to CFS participants using age, gender, ethnicity and body mass. Echocardiographic measures indicated that the severe CFS participants had 10.2% lower cardiac volume (i.e. stroke index and end-diastolic volume) and 25.1% lower contractility (velocity of circumferential shortening corrected by heart rate) than the control groups. Dual tag blood volume assessments indicated that the CFS groups had lower TBV, PV (plasma volume) and RBCV (red blood cell volume) than control groups. Of the CFS subjects with a TBV deficit (i.e. > or = 8% below ideal levels), the mean+/-S.D. percentage deficit in TBV, PV and RBCV were -15.4+/-4.0, -13.2+/-5.0 and -19.1+/-6.3% respectively. Lower cardiac volume levels in CFS were substantially corrected by controlling for prevailing TBV deficits, but were not affected by controlling for cardiac contractility levels. Analyses indicated that the TBV deficit explained 91-94% of the group differences in cardiac volume indices. Group differences in cardiac structure were offsetting and, hence, no differences emerged for left ventricular mass index. Therefore the findings indicate that lower cardiac volume levels, displayed primarily by subjects with severe CFS, were not linked to diminished cardiac contractility levels, but were probably a consequence of a co-morbid hypovolaemic condition. Further study is needed to address

System theory in industrial patient monitoring: an overview.

Science.gov (United States)

Baura, G D

2004-01-01

Patient monitoring refers to the continuous observation of repeating events of physiologic function to guide therapy or to monitor the effectiveness of interventions, and is used primarily in the intensive care unit and operating room. Commonly processed signals are the electrocardiogram, intraarterial blood pressure, arterial saturation of oxygen, and cardiac output. To this day, the majority of physiologic waveform processing in patient monitors is conducted using heuristic curve fitting. However in the early 1990s, a few enterprising engineers and physicians began using system theory to improve their core processing. Applications included improvement of signal-to-noise ratio, either due to low signal levels or motion artifact, and improvement in feature detection. The goal of this mini-symposium is to review the early work in this emerging field, which has led to technologic breakthroughs. In this overview talk, the process of system theory algorithm research and development is discussed. Research for industrial monitors involves substantial data collection, with some data used for algorithm training and the remainder used for validation. Once the algorithms are validated, they are translated into detailed specifications. Development then translates these specifications into DSP code. The DSP code is verified and validated per the Good Manufacturing Practices mandated by FDA.

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....

Prophylactic milrinone for the prevention of low cardiac output syndrome and mortality in children undergoing surgery for congenital heart disease.

Science.gov (United States)

Burkhardt, Barbara E U; Rücker, Gerta; Stiller, Brigitte

2015-03-25

Children with congenital heart disease often undergo heart surgery at a young age. They are at risk for postoperative low cardiac output syndrome (LCOS) or death. Milrinone may be used to provide inotropic and vasodilatory support during the immediate postoperative period. This review examines the effectiveness of prophylactic postoperative use of milrinone to prevent LCOS or death in children having undergone surgery for congenital heart disease. Electronic and manual literature searches were performed to identify randomised controlled trials. We searched CENTRAL, MEDLINE, EMBASE and Web of Science in February 2014 and conducted a top-up search in September 2014 as well as clinical trial registries and reference lists of published studies. We did not apply any language restrictions. Only randomised controlled trials were selected for analysis. We considered studies with newborn infants, infants, toddlers, and children up to 12 years of age. Two review authors independently extracted data according to a pre-defined protocol. We obtained additional information from all study authors. Three of the five included studies compared milrinone versus levosimendan, one study compared milrinone with placebo, and one compared milrinone verus dobutamine, with 101, 242, and 50 participants, respectively. Three trials were at low risk of bias while two were at higher risk of bias. The number and definitions of outcomes were non-uniform as well. In one study comparing two doses of milrinone and placebo, there was some evidence in an overall comparison of milrinone versus placebo that milrinone lowered risk for LCOS (risk ratio (RR) 0.52, 95% confidence interval (CI) 0.28 to 0.96; 227 participants). The results from two small studies do not provide enough information to determine whether milrinone increases the risk of LCOS when compared to levosimendan (RR 1.22, 95% CI 0.32 to 4.65; 59 participants). Mortality rates in the studies were low, and there was insufficient evidence to

Buerger's Disease and Anaesthesia: The Neglected Cardiac Angle

Directory of Open Access Journals (Sweden)

Shagun Bhatia Shah

2015-08-01

Full Text Available Distal limb amputations and respiratory complications are common in patients with Buerger’s disease. Nicotine in cigarette is arrhythmogenic as it blocks cardiac potassium channels. Preoperative Holter ECG monitoring may be useful if preoperative electrocardiogram is normal. If the patient is undergoing major surgery, preservative free lignocaine & amiodarone infusions and a cardioverter defibrillator should be available for the intraoperative cardiac rhythm disturbances.

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

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 (Pdisease...

Capabilities of infrared weld monitor

Energy Technology Data Exchange (ETDEWEB)

Sanders, P.G.; Keske, J.S.; Leong, K.H.; Kornecki, G.

1997-11-01

A non-obtrusive pre-aligned, solid-state device has been developed to monitor the primary infrared emissions during laser welding. The weld monitor output is a 100-1000 mV signal that depends on the beam power and weld characteristics. The DC level of this signal is related to weld penetration, while AC portions of the output can be correlated with surface irregularities and part misalignment or contamination. Changes in DC behavior are also noted for both full and deep penetration welds. Full penetration welds are signified by an abrupt reduction in the weld monitor output. Bead on plate welds were made on steel, aluminum, and magnesium with both a CW CO{sub 2} laser and a pulsed Nd:YAG laser to explore the relationships between the weld characteristics and the weld monitor output.

Cardiac Morphology and Function, and Blood Gas Transport in Aquaporin-1 Knockout Mice.

Directory of Open Access Journals (Sweden)

Samer eAl-Samir

2016-05-01

Full Text Available We have studied cardiac and respiratory functions of aquaporin- 1-deficient mice by the Pressure-Volume-loop technique and by blood gas analysis. In addition, the morphological properties of the animals’ hearts were analysed. In anesthesia under maximal dobutamine stimulation, the mice exhibit a moderately elevated heart rate of < 600 min-1 and an O2 consumption of ~0.6 ml/min/g, which is about twice the basal rate. In this state, which is similar to the resting state of the conscious animal, all cardiac functions including stroke volume and cardiac output exhibited resting values and were identical between deficient and wildtype animals. Likewise, pulmonary and peripheral exchange of O2 and CO2 were normal. In contrast, several morphological parameters of the heart tissue of deficient mice were altered: 1 left ventricular wall thickness was reduced by 12%, 2 left ventricular mass, normalized to tibia length, was reduced by 10-20%, 3 cardiac muscle fiber cross sectional area was decreased by 17%, and 4 capillary density was diminished by 10%. As the P-V-loop technique yielded normal end-diastolic and end-systolic left ventricular volumes, the deficient hearts are characterized by thin ventricular walls in combination with normal intraventricular volumes. The aquaporin-1-deficient heart thus seems to be at a disadvantage compared to the wildtype heart by a reduced left-ventricular wall thickness and an increased diffusion distance between blood capillaries and muscle mitochondria. While under the present quasi-resting conditions these morphological alterations have no consequences for cardiac function, we expect that the deficient hearts will show a reduced maximal cardiac output.

Neutron monitoring system

International Nuclear Information System (INIS)

Okido, Fumiyasu; Arita, Setsuo.

1994-01-01

The present invention concerns neutron monitoring for monitoring reactor power, and presents a generation state of abnormal signals by monitoring output signals from neutron sensors, judges abnormal signals at an excessively high level outputted from the sensors to a measuring operator or a reactor operator. That is, a threshold value judging means judges whether a sensor signal exceeds a predetermined threshold value or not. When it exceeds the value, recognition signals are outputted to a memory means. The memory means memorizes the times of input of the recognition signals on every period of interval signals outputted from a reference signal generation means. The memory content of the memory means and the previously inputted hysteresis of the sensor are compared and judged, to determine the extent of the degradation of the sensors and output the result of the judgement and hysteresis information to the display means. The input means accesses to the judging means and the memory means to retrieve and correct the content of the memory means and the hysteresis information inputted to the judging means. (I.S.)

Wireless cardiac action potential transmission with ultrasonically inserted silicon microprobes

International Nuclear Information System (INIS)

Shen, C J; Ramkumar, A; Lal, A; Gilmour, R F Jr

2011-01-01

This paper reports on the integration of ultrasonically inserted horn-shaped cardiac probes with wireless transmission of 3D cardiac action potential measurement for applications in ex vivo preparations such as monitoring the onset of ventricular fibrillation. Ultrasonically inserted silicon horn probes permit reduced penetration force during insertion, allowing silicon, a brittle material, to penetrate cardiac tissue. The probes also allow recording from multiple sites that are lithographically defined. An application-specific integrated circuit has been designed with a 40 dB amplifying stage and a frequency modulating oscillator at 95 MHz to wirelessly transmit the recorded action potentials. This ultrasonically inserted microprobe wireless system demonstrates the initial results in wireless monitoring of 3D action potential propagation, and the extraction of parameters of interest including the action potential duration and diastolic interval

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.

Cardiac nuclear medicine

International Nuclear Information System (INIS)

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

Artificial Neural Networks to Predict the Power Output of a PV Panel

Directory of Open Access Journals (Sweden)

Valerio Lo Brano

2014-01-01

Full Text Available The paper illustrates an adaptive approach based on different topologies of artificial neural networks (ANNs for the power energy output forecasting of photovoltaic (PV modules. The analysis of the PV module’s power output needed detailed local climate data, which was collected by a dedicated weather monitoring system. The Department of Energy, Information Engineering, and Mathematical Models of the University of Palermo (Italy has built up a weather monitoring system that worked together with a data acquisition system. The power output forecast is obtained using three different types of ANNs: a one hidden layer Multilayer perceptron (MLP, a recursive neural network (RNN, and a gamma memory (GM trained with the back propagation. In order to investigate the influence of climate variability on the electricity production, the ANNs were trained using weather data (air temperature, solar irradiance, and wind speed along with historical power output data available for the two test modules. The model validation was performed by comparing model predictions with power output data that were not used for the network's training. The results obtained bear out the suitability of the adopted methodology for the short-term power output forecasting problem and identified the best topology.

Movement monitoring device

International Nuclear Information System (INIS)

Ichikawa, Takashi; Yoneda, Yasuaki; Hanatsumi, Masaharu.

1997-01-01

The present invention provides a device suitable to accurate recognition for the moving state of reactor core fuels as an object to be monitored in a nuclear power plant. Namely, the device of the present invention prepares each of scheduled paths for the movement of the object to be monitored and executed moving paths along with the movement based on the information of the movement obtained from scheduled information for the movement of the reactor core fuels as a object to be monitored and the actual movement of the object to be monitored. The results of the preparation are outputted. As an output mode, (1) the results of preparation for each of the paths for movement and the results of the monitoring obtained by monitoring the state of the object to be monitored are jointed and outputted, (2) images showing each of the paths for the movement are formed, and the formed images are displayed on a screen, and (3) each of the moving paths is prepared as an image, and the image is displayed together with the image of the regions before and after the movement of the object to be monitored. In addition, obtained images of each of the paths for the movement and the monitored images obtained by monitoring the state of the object to be monitored are joined and displayed. (I.S.)

Length dependence of force generation exhibit similarities between rat cardiac myocytes and skeletal muscle fibres.

Science.gov (United States)

Hanft, Laurin M; McDonald, Kerry S

2010-08-01

According to the Frank-Starling relationship, increased ventricular volume increases cardiac output, which helps match cardiac output to peripheral circulatory demand. The cellular basis for this relationship is in large part the myofilament length-tension relationship. Length-tension relationships in maximally calcium activated preparations are relatively shallow and similar between cardiac myocytes and skeletal muscle fibres. During twitch activations length-tension relationships become steeper in both cardiac and skeletal muscle; however, it remains unclear whether length dependence of tension differs between striated muscle cell types during submaximal activations. The purpose of this study was to compare sarcomere length-tension relationships and the sarcomere length dependence of force development between rat skinned left ventricular cardiac myocytes and fast-twitch and slow-twitch skeletal muscle fibres. Muscle cell preparations were calcium activated to yield 50% maximal force, after which isometric force and rate constants (k(tr)) of force development were measured over a range of sarcomere lengths. Myofilament length-tension relationships were considerably steeper in fast-twitch fibres compared to slow-twitch fibres. Interestingly, cardiac myocyte preparations exhibited two populations of length-tension relationships, one steeper than fast-twitch fibres and the other similar to slow-twitch fibres. Moreover, myocytes with shallow length-tension relationships were converted to steeper length-tension relationships by protein kinase A (PKA)-induced myofilament phosphorylation. Sarcomere length-k(tr) relationships were distinct between all three cell types and exhibited patterns markedly different from Ca(2+) activation-dependent k(tr) relationships. Overall, these findings indicate cardiac myocytes exhibit varied length-tension relationships and sarcomere length appears a dominant modulator of force development rates. Importantly, cardiac myocyte length

Primary haemochromatosis. Early detection of commitment myocardium through cardiac magnetic resonance

International Nuclear Information System (INIS)

Corbella, F.; Rivas, Carlos; Dragonetti, Laura; Eyheremendy, Eduardo; Calo, Claudia

2009-01-01

Primary haemochromatosis is the most common genetic disease of the West (1 in 300 to 400 people). Cardiac involvement during its early stages is not detected by imaging techniques.During this period potentially lethal arrhythmias can occur. Using cardiac magnetic resonance (CMR) with T2 star sequence it is possible an early detection of cardiac involvement as well as a risk stratification and a monitoring the progress of the therapy. [es

Cardiac dysfunction in heart failure: the cardiologist's love affair with time.

Science.gov (United States)

Brutsaert, Dirk L

2006-01-01

Translating research into clinical practice has been a challenge throughout medical history. From the present review, it should be clear that this is particularly the case for heart failure. As a consequence, public awareness of this disease has been disillusionedly low, despite its prognosis being worse than that of most cancers and many other chronic diseases. We explore how over the past 150 years since Ludwig and Marey concepts about the evaluation of cardiac performance in patients with heart failure have emerged. From this historical-physiologic perspective, we have seen how 3 increasingly reductionist approaches or schools of thought have evolved in parallel, that is, an input-output approach, a hemodynamic pump approach, and a muscular pump approach. Each one of these has provided complementary insights into the pathophysiology of heart failure and has resulted in measurements or derived indices, some of which still being in use in present-day cardiology. From the third, most reductionist muscular pump approach, we have learned that myocardial and ventricular relaxation properties as well as temporal and spatial nonuniformities have been largely overlooked in the 2 other, input-output and hemodynamic pump, approaches. A key message from the present review is that relaxation and nonuniformities can be fully understood only from within the time-space continuum of cardiac pumping. As cyclicity and rhythm are, in some way, the most basic aspects of cardiac function, considerations of time should dominate over any measurement of cardiac performance as a muscular pump. Any measurement that is blind for the arrow of cardiac time should therefore be interpreted with caution. We have seen how the escape from the time domain-as with the calculation of LV ejection fraction-fascinating though as it may be, has undoubtedly served to hinder a rational scientific debate on the recent, so-called systolic-diastolic heart failure controversy. Lacking appreciation of early

Donor age is a predictor of early low output after heart transplantation.

Science.gov (United States)

Fujino, Takeo; Kinugawa, Koichiro; Nitta, Daisuke; Imamura, Teruhiko; Maki, Hisataka; Amiya, Eisuke; Hatano, Masaru; Kimura, Mitsutoshi; Kinoshita, Osamu; Nawata, Kan; Komuro, Issei; Ono, Minoru

2016-05-01

Using hearts from marginal donors could be related to increased risk of primary graft dysfunction and poor long-term survival. However, factors associated with delayed myocardial recovery after heart transplantation (HTx) remain unknown. We sought to clarify risk factors that predict early low output after HTx, and investigated whether early low output affects mid-term graft dysfunction. We retrospectively analyzed patients who had undergone HTx at The University of Tokyo Hospital. We defined early low output patients as those whose cardiac index (CI) was early low output group, and the others into early preserved output group. We performed univariable logistic analysis and found that donor age was the only significant factor that predicted early low output (odds ratio 1.107, 95% confidence interval 1.034-1.210, p=0.002). CI of early low output patients gradually increased and it caught up with that of early preserved output patients at 2 weeks after HTx (2.4±0.6 L/min/m(2) in early low output group vs 2.5±0.5 L/min/m(2) in early preserved output group, p=0.684). Plasma B-type natriuretic peptide concentration of early low output patients was higher (1118.5±1250.2 pg/ml vs 526.4±399.5 pg/ml; p=0.033) at 1 week, 703.6±518.4 pg/ml vs 464.6±509.0 pg/ml (p=0.033) at 2 weeks, and 387.7±231.9 pg/ml vs 249.4±209.5 pg/ml (p=0.010) at 4 weeks after HTx, and it came down to that of early preserved output patients at 12 weeks after HTx. Donor age was a predictor of early low output after HTx. We should be careful after HTx from old donors. However, hemodynamic parameters of early low output patients gradually caught up with those of early preserved output patients. Copyright © 2015 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Right atrial tamponade complicating cardiac operation: clinical, hemodynamic, and scintigraphic correlates

International Nuclear Information System (INIS)

Bateman, T.; Gray, R.; Chaux, A.; Lee, M.; De Robertis, M.; Berman, D.; Matloff, J.

1982-01-01

Persistent bleeding into the pericardial space in the early hours after cardiac operation not uncommonly results in cardiac tamponade. Single chamber tamponade also might be expected, since in this setting the pericardium frequently contains firm blood clots localized to the area of active bleeding. However, this complication has received very little attention in the surgical literature. We are therefore providing documentation that isolated right atrial tamponade can occur as a complication of cardiac operation and that there exists a potential for misdiagnosis and hence incorrect treatment of this condition. Right atrial tamponade may be recognized by a combination of low cardiac output, low blood pressure, prominent neck veins, right atrial pressure in excess of pulmonary capillary wedge pressure and right ventricular end-diastolic pressure, and a poor response to plasma volume expansion. Findings on chest roentgenogram and gated wall motion scintigraphy may be highly suggestive. This review should serve to increase awareness of this complication and to provide some helpful diagnostic clues

Power distribution monitor for nuclear reactor

International Nuclear Information System (INIS)

Nishizawa, Yasuo; Kiguchi, Takashi.

1974-01-01

Object: To compare the measured local power region monitor (LPRM) index with the result of a primary calculation to correct the threshold condition for the primary calculation thereby to rapidly grasp and monitor the existing power distribution. Structure: The index of an LPRM disposed in a nuclear reactor is processed in a data processor to remove therefrom a noise, and transmitted to a threshold condition processor to be stored therein. The LPRM index measured by the threshold condition processor is compared with the calculated LPRM value transmitted from the primary processor, whereby the threshold condition is corrected and transmitted to the primary processor. After the completion of calculation, the traversing incore probe (TIP) indexing value is converted to a thermal output distribution or a linear output density distribution and transmitted to an output indicator or an output typewriter. The operator may monitor the existing power distribution by monitoring the output indicator. (Kamimura, M.)

A multichannel bioimpedance monitor for full-body blood flow monitoring

Czech Academy of Sciences Publication Activity Database

Vondra, Vlastimil; Jurák, Pavel; Viščor, Ivo; Halámek, Josef; Leinveber, P.; Matějková, M.; Soukup, L.

2016-01-01

Roč. 61, č. 1 (2016), s. 107-118 ISSN 0013-5585 R&D Projects: GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01; GA ČR GAP102/12/2034 Institutional support: RVO:68081731 Keywords : bioimpedance * blood flow * cardiac output * multichannel measurement * non- invasive measurements * pulse wave velocity Subject RIV: FS - Medical Facilities ; Equipment Impact factor: 0.915, year: 2016

Nuclear cardiac ejection fraction and cardiac index in abdominal aortic surgery

International Nuclear Information System (INIS)

Fiser, W.P.; Thompson, B.W.; Thompson, A.R.; Eason, C.; Read, R.C.

1983-01-01

Since atherosclerotic heart disease results in more than half of the perioperative deaths that follow abdominal aortic surgery, a prospective protocol was designed for preoperative evaluation and intraoperative hemodynamic monitoring. Twenty men who were prepared to undergo elective operation for aortoiliac occlusive disease (12 patients) and abdominal aortic aneurysm (eight patients) were evaluated with a cardiac scan and right heart catheterization. The night prior to operation, each patient received volume loading with crystalloid based upon ventricular performance curves. At the time of the operation, all patients were anesthetized with narcotics and nitrous oxide, and hemodynamic parameters were recorded throughout the operation. Aortic crossclamping resulted in a marked depression in CI in all patients. CI remained depressed after unclamping in the majority of patients. There were two perioperative deaths, both from myocardial infarction or failure. Both patients had ejection fractions less than 30% and initial CIs less than 2 L/M2, while the survivors' mean ejection fraction was 63% +/- 1 and their mean CI was 3.2 L/M2 +/- 0.6. The authors conclude that preoperative evaluation of ejection fraction can select those patients at a high risk of cardiac death from abdominal aortic operation. These patients should receive intensive preoperative monitoring with enhancement of ventricular performance

Proton Beam Therapy Interference With Implanted Cardiac Pacemakers

International Nuclear Information System (INIS)

Oshiro, Yoshiko; Sugahara, Shinji; Noma, Mio; Sato, Masato; Sakakibara, Yuzuru; Sakae, Takeji; Hayashi, Yasutaka; Nakayama, Hidetsugu; Tsuboi, Koji; Fukumitsu, Nobuyoshi; Kanemoto, Ayae; Hashimoto, Takayuki; Tokuuye, Koichi

2008-01-01

Purpose: To investigate the effect of proton beam therapy (PBT) on implanted cardiac pacemaker function. Methods and Materials: After a phantom study confirmed the safety of PBT in patients with cardiac pacemakers, we treated 8 patients with implanted pacemakers using PBT to a total tumor dose of 33-77 gray equivalents (GyE) in dose fractions of 2.2-6.6 GyE. The combined total number of PBT sessions was 127. Although all pulse generators remained outside the treatment field, 4 patients had pacing leads in the radiation field. All patients were monitored by means of electrocardiogram during treatment, and pacemakers were routinely examined before and after PBT. Results: The phantom study showed no effect of neutron scatter on pacemaker generators. In the study, changes in heart rate occurred three times (2.4%) in 2 patients. However, these patients remained completely asymptomatic throughout the PBT course. Conclusions: PBT can result in pacemaker malfunctions that manifest as changes in pulse rate and pulse patterns. Therefore, patients with cardiac pacemakers should be monitored by means of electrocardiogram during PBT

The Western Denmark Cardiac Computed Tomography Registry

DEFF Research Database (Denmark)

Nielsen, Lene Hüche; Nørgaard, Bjarne Linde; Tilsted, Hans-Henrik

2014-01-01

BACKGROUND: As a subregistry to the Western Denmark Heart Registry (WDHR), the Western Denmark Cardiac Computed Tomography Registry (WDHR-CCTR) is a clinical database established in 2008 to monitor and improve the quality of cardiac computed tomography (CT) in Western Denmark. OBJECTIVE: We...... examined the content, data quality, and research potential of the WDHR-CCTR. METHODS: We retrieved 2008-2012 data to examine the 1) content; 2) completeness of procedure registration using the Danish National Patient Registry as reference; 3) completeness of variable registration comparing observed vs...

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

Directory of Open Access Journals (Sweden)

Marco A.M. Gomes

2000-04-01

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

Reactor power distribution monitor

International Nuclear Information System (INIS)

Hoizumi, Atsushi.

1986-01-01

Purpose: To grasp the margin for the limit value of the power distribution peaking factor inside the reactor under operation by using the reactor power distribution monitor. Constitution: The monitor is composed of the 'constant' file, (to store in-reactor power distributions obtained from analysis), TIP and thermocouple, lateral output distribution calibrating apparatus, axial output distribution synthesizer and peaking factor synthesizer. The lateral output distribution calibrating apparatus is used to make calibration by comparing the power distribution obtained from the thermocouples to the power distribution obtained from the TIP, and then to provide the power distribution lateral peaking factors. The axial output distribution synthesizer provides the power distribution axial peaking factors in accordance with the signals from the out-pile neutron flux detector. These axial and lateral power peaking factors are synthesized with high precision in the three-dimensional format and can be monitored at any time. (Kamimura, M.)

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.).

Simultaneous determination of dynamic cardiac metabolism and function using PET/MRI.

Science.gov (United States)

Barton, Gregory P; Vildberg, Lauren; Goss, Kara; Aggarwal, Niti; Eldridge, Marlowe; McMillan, Alan B

2018-05-01

Cardiac metabolic changes in heart disease precede overt contractile dysfunction. However, metabolism and function are not typically assessed together in clinical practice. The purpose of this study was to develop a cardiac positron emission tomography/magnetic resonance (PET/MR) stress test to assess the dynamic relationship between contractile function and metabolism in a preclinical model. Following an overnight fast, healthy pigs (45-50 kg) were anesthetized and mechanically ventilated. 18 F-fluorodeoxyglucose ( 18 F-FDG) solution was administered intravenously at a constant rate of 0.01 mL/s for 60 minutes. A cardiac PET/MR stress test was performed using normoxic gas (F I O 2  = .209) and hypoxic gas (F I O 2  = .12). Simultaneous cardiac imaging was performed on an integrated 3T PET/MR scanner. Hypoxic stress induced a significant increase in heart rate, cardiac output, left ventricular (LV) ejection fraction (EF), and peak torsion. There was a significant decline in arterial SpO 2 , LV end-diastolic and end-systolic volumes in hypoxia. Increased LV systolic function was coupled with an increase in myocardial FDG uptake (Ki) during hypoxic stress. PET/MR with continuous FDG infusion captures dynamic changes in both cardiac metabolism and contractile function. This technique warrants evaluation in human cardiac disease for assessment of subtle functional and metabolic abnormalities.

Association of morning blood pressure surge with carotid intima-media thickness and cardiac dysfunction in patients with cardiac syndrome-X.

Science.gov (United States)

Mahfouz, Ragab A; Goda, Mohammad; Galal, Islam; Ghareb, Mohamed S

2018-05-23

Background & hypothesis: We hypothesized that exaggerated morning blood pressure surge, may contribute in cardiac dysfunction and arterial stiffness in patients with cardiac syndrome X. Thus we investigated the impact of morning blood pressure surge on cardiac function and carotid intima-media thickness in subjects with cardiac syndrome X. We studied patients with cardiac syndrome X using ambulatory blood pressure monitoring and investigated the association of morning blood pressure surge with carotid intima thickness, left atrial volume index and left ventricular filling (E/e'). Seventy patients with cardiac syndrome X were enrolled for the study and compared with 70 age and sex matched controls. Patients with cardiac syndrome X were stratified based on the systolic morning blood pressure surge value of control subjects to patients with exaggerated blood pressure surge (n = 42) and those with normal morning blood pressure surge (n = 28). Basal heart rate (p blood pressure surge group than those with morning blood pressure surge group. Morning blood pressure surge was significantly correlated with carotid intima-media thickness, high sensitive C-reactive protein, left atrial volume index and E/e' ratio in patients with cardiac syndrome X. In multivariate analysis, exaggerated morning blood pressure surge was the only independent predictor of increased carotid intima-media thickness (OR = 2.379; p blood pressure surge is an independent predictor for arterial stiffness and diastolic dysfunction in patients with cardiac syndrome X.

LOAD THAT MAXIMIZES POWER OUTPUT IN COUNTERMOVEMENT JUMP

Directory of Open Access Journals (Sweden)

Pedro Jimenez-Reyes

2016-02-01

Full Text Available ABSTRACT Introduction: One of the main problems faced by strength and conditioning coaches is the issue of how to objectively quantify and monitor the actual training load undertaken by athletes in order to maximize performance. It is well known that performance of explosive sports activities is largely determined by mechanical power. Objective: This study analysed the height at which maximal power output is generated and the corresponding load with which is achieved in a group of male-trained track and field athletes in the test of countermovement jump (CMJ with extra loads (CMJEL. Methods: Fifty national level male athletes in sprinting and jumping performed a CMJ test with increasing loads up to a height of 16 cm. The relative load that maximized the mechanical power output (Pmax was determined using a force platform and lineal encoder synchronization and estimating the power by peak power, average power and flight time in CMJ. Results: The load at which the power output no longer existed was at a height of 19.9 ± 2.35, referring to a 99.1 ± 1% of the maximum power output. The load that maximizes power output in all cases has been the load with which an athlete jump a height of approximately 20 cm. Conclusion: These results highlight the importance of considering the height achieved in CMJ with extra load instead of power because maximum power is always attained with the same height. We advise for the preferential use of the height achieved in CMJEL test, since it seems to be a valid indicative of an individual's actual neuromuscular potential providing a valid information for coaches and trainers when assessing the performance status of our athletes and to quantify and monitor training loads, measuring only the height of the jump in the exercise of CMJEL.

Role of Nuclear Medicine in the cardiac resinchronization therapy

Energy Technology Data Exchange (ETDEWEB)

Brandao, Simone Cristina Soares, E-mail: simonecordis@yahoo.com.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Giorgi, Maria Clementina Pinto; D' Orio, Silvana Angelina; Meneghetti, Jose Claudio [Instituto do Coracao (InCor/FM/USP), Sao Paulo, SP (Brazil)

2011-10-15

Cardiac resynchronization therapy (CRT) emerged as one of the most promising approaches in the treatment of cardiac dyssynchrony in heart failure patients' refractory to medical treatment. However, despite very promising clinical and functional results, individual response analyses show that a significant number of patients do not respond to treatment. The role of nuclear medicine and molecular imaging in the selection of CRT candidates by the assessment of cardiac dyssynchrony, myocardial viability, myocardial perfusion and blood flow and sympathetic cardiac activity has been discussed in this review. The potential utilization of this tool to improve the comprehension of detrimental effects of dyssynchrony on cardiac function and the evaluation and monitoring of the response to CRT were also considered. Other molecular targets that characterize glucose and fatty acid metabolism, apoptosis, angiotensin converting enzyme activity and angiogenesis that can be evaluated with this technique were described. (author)

Role of Nuclear Medicine in the cardiac resinchronization therapy

Energy Technology Data Exchange (ETDEWEB)

Brandao, Simone Cristina Soares, E-mail: simonecordis@yahoo.com.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Giorgi, Maria Clementina Pinto; D' Orio, Silvana Angelina; Meneghetti, Jose Claudio [Instituto do Coracao (InCor/FM/USP), Sao Paulo, SP (Brazil)

2011-10-15

Cardiac resynchronization therapy (CRT) emerged as one of the most promising approaches in the treatment of cardiac dyssynchrony in heart failure patients' refractory to medical treatment. However, despite very promising clinical and functional results, individual response analyses show that a significant number of patients do not respond to treatment. The role of nuclear medicine and molecular imaging in the selection of CRT candidates by the assessment of cardiac dyssynchrony, myocardial viability, myocardial perfusion and blood flow and sympathetic cardiac activity has been discussed in this review. The potential utilization of this tool to improve the comprehension of detrimental effects of dyssynchrony on cardiac function and the evaluation and monitoring of the response to CRT were also considered. Other molecular targets that characterize glucose and fatty acid metabolism, apoptosis, angiotensin converting enzyme activity and angiogenesis that can be evaluated with this technique were described. (author)

Implantable sensors for heart failure monitoring

Directory of Open Access Journals (Sweden)

P. Shasha Liu

2013-12-01

Implantable sensors in the CRT device offer a unique opportunity for continuous monitoring of a patient's clinical HF status by measuring cardiac rhythm, intracardiac pressures, cardiac events, and physical activity, as well as detecting any device malfunction. Detecting early signs of a deteriorating clinical condition allows prompt preemptive medical intervention to optimize HF management. As a result, not only healthcare professionals will benefit from a reduction in hospitalizations and routine in-office follow-ups, but also patients will benefit from efficient management of their HF. This review highlights the latest available device-based remote monitoring systems and the most up-to-date evidence for the use of remote monitoring in CRT.

Commissioning of output factors for uniform scanning proton beams

International Nuclear Information System (INIS)

Zheng Yuanshui; Ramirez, Eric; Mascia, Anthony; Ding Xiaoning; Okoth, Benny; Zeidan, Omar; Hsi Wen; Harris, Ben; Schreuder, Andries N.; Keole, Sameer

2011-01-01

Purpose: Current commercial treatment planning systems are not able to accurately predict output factors and calculate monitor units for proton fields. Patient-specific field output factors are thus determined by either measurements or empirical modeling based on commissioning data. The objective of this study is to commission output factors for uniform scanning beams utilized at the ProCure proton therapy centers. Methods: Using water phantoms and a plane parallel ionization chamber, the authors first measured output factors with a fixed 10 cm diameter aperture as a function of proton range and modulation width for clinically available proton beams with ranges between 4 and 31.5 cm and modulation widths between 2 and 15 cm. The authors then measured the output factor as a function of collimated field size at various calibration depths for proton beams of various ranges and modulation widths. The authors further examined the dependence of the output factor on the scanning area (i.e., uncollimated proton field), snout position, and phantom material. An empirical model was developed to calculate the output factor for patient-specific fields and the model-predicted output factors were compared to measurements. Results: The output factor increased with proton range and field size, and decreased with modulation width. The scanning area and snout position have a small but non-negligible effect on the output factors. The predicted output factors based on the empirical modeling agreed within 2% of measurements for all prostate treatment fields and within 3% for 98.5% of all treatment fields. Conclusions: Comprehensive measurements at a large subset of available beam conditions are needed to commission output factors for proton therapy beams. The empirical modeling agrees well with the measured output factor data. This investigation indicates that it is possible to accurately predict output factors and thus eliminate or reduce time-consuming patient-specific output

47. A cardiac center experience with Brugada syndrome who survived sudden cardiac death

Directory of Open Access Journals (Sweden)

I. Suliman

2016-07-01

Full Text Available Brugada syndrome is a heritable arrhythmia syndrome that is characterized by an electrocardiographic pattern consisting of coved-type ST-segment elevation (2 mm followed by a negative T wave in the right precordial leads, V1 through V3 (often referred to as type 1 Brugada electrocardiographic pattern, here we describe 3 cases of Brugada who survived sudden cardiac death (SCD cardiac center experience with survived Brugada syndrome patients – case series. First Case: The Father 45 years old male, presented in 2005 after involvement in unprovoked motor vehicle accident, the patient was the driver who lost consciousness and rushed to the hospital. On arrival to our ER and putting the patient on the bed, the ER doctor observed a brief episode of VF on the monitor. The patient was taken to the catheterization Lab , his coronaries were normal. The diagnosis of Brugada was established and the patient received a defibrillator. At That Time all family members were screened and were negative. Second Case: The Son of the first patient 5 years later his 23 years old male rushed to our ER after he lost consciousness, he was passenger in the car of his friend. Third Case: The pilot A military pilot aged a male 35 years old was in very good health when he lost consciousness and brought to the hospital after resuscitation in 2005. He had full invasive cardiac evaluation, subsequently he received a defibrillator in the same admission period, till 2015 he is doing fine. Brugada syndrome is associated with high tendency for sudden cardiac death. In our three cases the first clinical presentation was survived sudden cardiac death (SCD and all three male patients survived. We did not encounter a female patient who survived sudden cardiac death.

[Cardiac valvular disease and pregnancy. Haemodynamic aspects and importance of decubitus].

Science.gov (United States)

Lo Cicero, G; Cellina, G; Brina, A

1982-01-01

During the 3rd trimester of pregnancy, 26 women with aortic or mitral valve disease (II class NYHA) have undergone bedside right heart catheterization. Total pulmonary resistances (RPT) have been studied in supine (DS) and lateral (DL) decubitus. The results are compared with those of 7 normal women. It is known that the change from the supine to the lateral posture increases venous return (and cardiac output) by removing the compression which the pregnant uterus causes to the inferior vena cava. This is achieved without increasing the mean pulmonary pressure (PPM) and total pulmonary resistances (RPT); women with mitral and aortic stenosis have little or no increase of cardiac output but always a marked increase of PPM and RPT; the response in patients with aortic and mitral incompetence is closer to normal; an intermediate response was observed in patients with a mitral stenosis and insufficiency. The valvular heart diseases with stenosis badly tolerate the increased cardiovascular burden of pregnancy and are unable to accommodate the increased venous return induced by postural changes, which induces marked elevation of pulmonary pressure and resistances.

Cardiac involvement in canine babesiosis : review article

Directory of Open Access Journals (Sweden)

R.G. Lobetti

2005-06-01

Full Text Available Cardiac dysfunction in canine babesiosis has traditionally been regarded as a rare complication, with the majority of lesions reported as incidental findings at post-mortem examination. Recent studies have, however, demonstrated cardiac lesions in canine babesiosis. Cardiac troponins, especially troponin I, are sensitive markers of myocardial injury in canine babesiosis, and the magnitude of elevation of plasma troponin I concentrations appears to be proportional to the severity of the disease. ECG changes in babesiosis are similar to the pattern described for myocarditis and myocardial ischaemia and together with histopathological findings indicate that the heart suffers from the same pathological processes described in other organs in canine babesiosis, namely inflammation and hypoxia. The clinical application of the ECG appears to be limited and thus cardiovascular assessment should be based on functional monitoring rather than an ECG tracing. On cardiac histopathology from dogs that succumbed to babesiosis, haemorrhage, necrosis, inflammation and fibrin microthrombi in the myocardium were documented, all of which would have resulted in ECG changes and elevations in cardiac troponin. Myocardial damage causes left ventricular failure, which will result in hypotension and an expansion of the plasma volume due to homeostatic mechanisms.

[Pressure sensors to prevent cardiac decompensation].

Science.gov (United States)

Klug, Didier

2017-11-01

Most cases of hospitalisation for heart failure are preceded by episodes of cardiac decompensation. Preventing these episodes would improve quality of life and reduce mortality and treatment costs. The monitoring of intracardiac pressures, using innovative sensors, coupled with telemedicine, offers interesting perspectives. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Ambulatory monitoring of left ventricular function in patients with Parkinson`s disease and postural hypotension

Energy Technology Data Exchange (ETDEWEB)

Nappi, A. [Dept. of Nuclear Medicine, Univ. ``Federico II``, Naples (Italy); Cuocolo, A. [Dept. of Nuclear Medicine, Univ. ``Federico II``, Naples (Italy); Iazzetta, N. [Inst. of Internal Medicine and Metabolic Diseases, Univ. ``Federico II``, Naples (Italy); Ferrara, L.A. [Inst. of Internal Medicine and Metabolic Diseases, Univ. ``Federico II``, Naples (Italy); Marotta, T. [Inst. of Internal Medicine and Metabolic Diseases, Univ. ``Federico II``, Naples (Italy); Pace, L. [Dept. of Nuclear Medicine, Univ. ``Federico II``, Naples (Italy); Nicolai, E. [Dept. of Nuclear Medicine, Univ. ``Federico II``, Naples (Italy); De Michele, G. [Inst. of Neurological Sciences, Univ. ``Federico II``, Naples (Italy); Campanella, G. [Inst. of Neurological Sciences, Univ. ``Federico II``, Naples (Italy); Salvatore, M. [National Cancer Inst., Naples (Italy); Postiglione, A. [Inst. of Internal Medicine and Metabolic Diseases, Univ. ``Federico II``, Naples (Italy)

1994-12-01

Left ventricular (LV) function was continuously monitored using a radionuclide detector (VEST) after intravenous injection of 25 mCi technetium-99m labelled red blood cells in nine patients with Parkinson`s disease and postural hypotension (group 1) and ten patients with Parkinson`s disease but without postural hypotension (group 2). LV function and blood pressure were monitored in the supine position for 15 min (period A), upon changing posture from the supine to the upright position for 10 min (period B), and upon returning to the supine position for 10 min (period C). In group 1, the passage from period A to period B induced a significant decrease in end-diastolic volume, end-systolic volume and ejection fraction (all P<0.01). In group 2, ejection fraction increased (P<0.05) upon changing posture from the supine to the upright position. Ejection fraction (F=33, P<0.01), end-diastolic volume (F=9, P<0.05) and end-systolic volume (F=10, P<0.05) were significantly different between the two groups. In group 1, stroke volume, cardiac output and vascular peripheral resistance decreased from period A to period B (all P<0.001). In group 2, no changes in stroke volume, cardiac output and vascular peripheral resistance were observed from period A to period B. All parameters were similar in the two groups during the periods A and C. Upon changing posture from the supine to the upright position, patients with Parkinson`s disease and postural hypotension showed marked changes in parameters of LV function induced by vascular abnormalities. The results of this study may help to clarify the potential risk of sudden postural changes in such patients, which may cause fainting, syncope and increased risk of ischaemic coronary and cerebrovascular attacks and of lower limb fractures. (orig.)

Intrinsic cardiac nervous system in tachycardia induced heart failure.

Science.gov (United States)

Arora, Rakesh C; Cardinal, Rene; Smith, Frank M; Ardell, Jeffrey L; Dell'Italia, Louis J; Armour, J Andrew

2003-11-01

The purpose of this study was to test the hypothesis that early-stage heart failure differentially affects the intrinsic cardiac nervous system's capacity to regulate cardiac function. After 2 wk of rapid ventricular pacing in nine anesthetized canines, cardiac and right atrial neuronal function were evaluated in situ in response to enhanced cardiac sensory inputs, stimulation of extracardiac autonomic efferent neuronal inputs, and close coronary arterial administration of neurochemicals that included nicotine. Right atrial neuronal intracellular electrophysiological properties were then evaluated in vitro in response to synaptic activation and nicotine. Intrinsic cardiac nicotine-sensitive, neuronally induced cardiac responses were also evaluated in eight sham-operated, unpaced animals. Two weeks of rapid ventricular pacing reduced the cardiac index by 54%. Intrinsic cardiac neurons of paced hearts maintained their cardiac mechano- and chemosensory transduction properties in vivo. They also responded normally to sympathetic and parasympathetic preganglionic efferent neuronal inputs, as well as to locally administered alpha-or beta-adrenergic agonists or angiotensin II. The dose of nicotine needed to modify intrinsic cardiac neurons was 50 times greater in failure compared with normal preparations. That dose failed to alter monitored cardiovascular indexes in failing preparations. Phasic and accommodating neurons identified in vitro displayed altered intracellular membrane properties compared with control, including decreased membrane resistance, indicative of reduced excitability. Early-stage heart failure differentially affects the intrinsic cardiac nervous system's capacity to regulate cardiodynamics. While maintaining its capacity to transduce cardiac mechano- and chemosensory inputs, as well as inputs from extracardiac autonomic efferent neurons, intrinsic cardiac nicotine-sensitive, local-circuit neurons differentially remodel such that their capacity to

Implementation and reimbursement of remote monitoring for cardiac implantable electronic devices in Europe: a survey from the health economics committee of the European Heart Rhythm Association.

Science.gov (United States)

Mairesse, Georges H; Braunschweig, Frieder; Klersy, Katherine; Cowie, Martin R; Leyva, Francisco

2015-05-01

Remote monitoring (RM) of cardiac implantable electronic devices (CIEDs) permits early detection of arrhythmias, device, and lead failure and may also be useful in risk-predicting patient-related outcomes. Financial benefits for patients and healthcare organizations have also been shown. We sought to assess the implementation and funding of RM of CIEDs, including conventional pacemakers (PMs), implantable cardioverter defibrillators (ICDs), and cardiac resynchronization therapy (CRT) devices in Europe. Electronic survey from 43 centres in 15 European countries. In the study sample, RM was available in 22% of PM patients, 74% of ICD patients, and 69% of CRT patients. The most significant perceived benefits were the early detection of atrial arrhythmias in pacemaker patients, lead failure in ICD patients, and worsening heart failure in CRT patients. Remote monitoring was reported to lead a reduction of in-office follow-ups for all devices. The most important reported barrier to the implementation of RM for all CIEDs was lack of reimbursement (80% of centres). Physicians regard RM of CIEDs as a clinically useful technology that affords significant benefits for patients and healthcare organizations. Remote monitoring, however, is perceived as increasing workload. Reimbursement for RM is generally perceived as a major barrier to implementation. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

Results of remote follow-up and monitoring in young patients with cardiac implantable electronic devices.

Science.gov (United States)

Silvetti, Massimo S; Saputo, Fabio A; Palmieri, Rosalinda; Placidi, Silvia; Santucci, Lorenzo; Di Mambro, Corrado; Righi, Daniela; Drago, Fabrizio

2016-01-01

Remote monitoring is increasingly used in the follow-up of patients with cardiac implantable electronic devices. Data on paediatric populations are still lacking. The aim of our study was to follow-up young patients both in-hospital and remotely to enhance device surveillance. This is an observational registry collecting data on consecutive patients followed-up with the CareLink system. Inclusion criteria were a Medtronic device implanted and patient's willingness to receive CareLink. Patients were stratified according to age and presence of congenital/structural heart defects (CHD). A total of 221 patients with a device - 200 pacemakers, 19 implantable cardioverter defibrillators, and two loop recorders--were enrolled (median age of 17 years, range 1-40); 58% of patients were younger than 18 years of age and 73% had CHD. During a follow-up of 12 months (range 4-18), 1361 transmissions (8.9% unscheduled) were reviewed by technicians. Time for review was 6 ± 2 minutes (mean ± standard deviation). Missed transmissions were 10.1%. Events were documented in 45% of transmissions, with 2.7% yellow alerts and 0.6% red alerts sent by wireless devices. No significant differences were found in transmission results according to age or presence of CHD. Physicians reviewed 6.3% of transmissions, 29 patients were contacted by phone, and 12 patients underwent unscheduled in-hospital visits. The event recognition with remote monitoring occurred 76 days (range 16-150) earlier than the next scheduled in-office follow-up. Remote follow-up/monitoring with the CareLink system is useful to enhance device surveillance in young patients. The majority of events were not clinically relevant, and the remaining led to timely management of problems.

[Cardiac involvement in Churg-Strauss syndrome].

Science.gov (United States)

Brucato, Antonio; Maestroni, Silvia; Masciocco, Gabriella; Ammirati, Enrico; Bonacina, Edgardo; Pedrotti, Patrizia

2015-09-01

agents, particularly cyclophosphamide in case of myocardial inflammation. Thus, early diagnosis of cardiac involvement and subsequent therapy may prevent progression of cardiac disease. At present, the role of troponin and brain natriuretic peptide in monitoring and therapy remains unclear. Orthotopic heart transplantation is feasible in case of severe disease, even if the experience is limited in -EGPA, and optimal post-transplantation immunosuppressive strategy has yet to be defined.

A patient self-assessment tool for cardiac rehabilitation.

Science.gov (United States)

Phelan, C; Finnell, M D; Mottla, K A

1989-01-01

A patient self-assessment tool was designed, tested, and implemented to promote cardiac-specific data collection, based on Gordon's Functional Health Patterns, to maximize patient/family involvement in determining a plan of care, and to streamline primary nurses' documentation requirements. Retrospective and concurrent chart reviews provided data for quality assurance monitoring. The results of the monitoring demonstrated that the self-assessment tool markedly improved the patient-specific data base.

[Fluid therapy in cardiac surgery. An update].

Science.gov (United States)

Boix, E; Vicente, R; Pérez-Artacho, J

2014-01-01

The anesthetist has 2 major tools for optimizing haemodynamics in cardiac surgery: Vasoactive drugs and the intravascular volume. It is necessary to identify which patients would benefit from one or the other therapies for a suitable response to treatment. Hemodynamic monitoring with the different existing parameters (pressure, volumetric static, volumetric functional and echocardiography) allows the management of these patients to be optimized. In this article a review is presented on the most recent and relevant publications, and the different tools available to control the management of the fluid therapy in this context, and to suggest a few guidelines for the haemodynamics monitoring of patients submitted to cardiac surgery. A systematic search has been made in PubMed, limiting the results to the publications over the last five years up to February 2012. Copyright © 2012 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.

Sacral Neuromodulation in Patients With a Cardiac Pacemaker

Directory of Open Access Journals (Sweden)

Abdullah A. Gahzi

2016-09-01

Full Text Available The objective of this study was to describe our experience using sacral neuromodulation to treat urinary urgency, frequency, urge incontinence, and chronic urinary retention in patients with cardiac pacemakers. With the increasingly widespread use of InterStim for bladder function restoration, we are seeing more complex patients with multiple comorbidities, including cardiac conditions. Herein, we report 3 cases of individuals with cardiac pacemakers who underwent InterStim implantation to treat urinary conditions. This study is a case series of 3 patients with cardiac pacemakers who underwent sacral neuromodulation to treat refractory voiding dysfunction. The initial patient screening for InterStim therapy involved percutaneous nerve evaluation (PNE, in which a temporary untined lead wire was placed through the S3 foramen. Patients who did not respond to PNE proceeded to a staged implant. All patients in this study had a greater than 50% improvement of their urinary symptoms during the initial trial and underwent placement of the InterStim implantable pulse generator (IPG. Postoperative programming was done under electrocardiogram monitoring by a cardiologist. No interference was observed between the Inter-Stim IPG and the cardiac pacemaker. In this group of patients, sacral neuromodulation in the presence of a cardiac pacemaker appears to have been safe.

What Limits Cardiac Performance during Exercise in Normal Subjects and in Healthy Fontan Patients?

Directory of Open Access Journals (Sweden)

André La Gerche

2010-01-01

Full Text Available Exercise is an important determinant of health but is significantly reduced in the patient with a univentricular circulation. Normal exercise physiology mandates an increase in pulmonary artery pressures which places an increased work demand on the right ventricle (RV. In a biventricular circulation with pathological increases in pulmonary vascular resistance and/or reductions in RV function, exercise-induced augmentation of cardiac output is limited. Left ventricular preload reserve is dependent upon flow through the pulmonary circulation and this requires adequate RV performance. In the Fontan patient, the reasons for exercise intolerance are complex. In those patients with myocardial dysfunction or other pathologies of the circulatory components, it is likely that these abnormalities serve as a limitation to cardiac performance during exercise. However, in the healthy Fontan patient, it may be the absence of a sub-pulmonary pump which limits normal increases in pulmonary pressures, trans-pulmonary flow requirements and cardiac output. If so, performance will be exquisitely dependent on pulmonary vascular resistance. This provides a potential explanation as to why pulmonary vasodilators may improve exercise tolerance. As has recently been demonstrated, these agents may offer an important new treatment strategy which directly addresses the physiological limitations in the Fontan patient.

The Normal Electrocardiogram: Resting 12-Lead and Electrocardiogram Monitoring in the Hospital.

Science.gov (United States)

Harris, Patricia R E

2016-09-01

The electrocardiogram (ECG) is a well-established diagnostic tool extensively used in clinical settings. Knowledge of cardiac rhythm and mastery of cardiac waveform interpretation are fundamental for intensive care nurses. Recognition of the normal findings for the 12-lead ECG and understanding the significance of changes from baseline in continuous cardiac monitoring are essential steps toward ensuring safe patient care. This article highlights historical developments in electrocardiography, describes the normal resting 12-lead ECG, and discusses the need for continuous cardiac monitoring. In addition, future directions for the ECG are explored briefly. Copyright © 2016 Elsevier Inc. All rights reserved.

Cardiac arrest due to lymphocytic colitis: a case report

Directory of Open Access Journals (Sweden)

Groth Kristian A

2012-03-01

Full Text Available Abstract Introduction We present a case of cardiac arrest due to hypokalemia caused by lymphocytic colitis. Case presentation A 69-year-old Caucasian man presented four months prior to a cardiac arrest with watery diarrhea and was diagnosed with lymphocytic colitis. Our patient experienced a witnessed cardiac arrest at his general practitioner's surgery. Two physicians and the emergency medical services resuscitated our patient for one hour and four minutes before arriving at our university hospital. Our patient was defibrillated 16 times due to the recurrence of ventricular tachyarrhythmias. An arterial blood sample revealed a potassium level of 2.0 mmol/L (reference range: 3.5 to 4.6 mmol/L and pH 6.86 (reference range: pH 7.37 to 7.45. As the potassium level was corrected, the propensity for ventricular tachyarrhythmias ceased. Our patient recovered from his cardiac arrest without any neurological deficit. Further tests and examinations revealed no other reason for the cardiac arrest. Conclusion Diarrhea can cause life-threatening situations due to the excretion of potassium, ultimately causing cardiac arrest due to hypokalemia. Physicians treating patients with severe diarrhea should consider monitoring their electrolyte levels.

Comparison of an Endotracheal Cardiac Output Monitor to a Pulmonary Artery Catheter

Science.gov (United States)

2017-12-04

8217-’ ’ ,, Background In combat, initial resuscitation and life saving measures are in itiated by securing a patent airway and administering fluid therapy. Wh...ile methods of fluid resuscitation remain controversial , maintenance of a patent airway and hemodynamic stabi lity as indicated by invasive...monito ri ng can influence the overall outcome of an injured individual. A patent airway may be maintained via an endotracheal tube . The use of

The Role of Levosimendan in Patients with Decreased Left Ventricular Function Undergoing Cardiac Surgery

Directory of Open Access Journals (Sweden)

Marija Bozhinovska

2016-06-01

Full Text Available The postoperative low cardiac output is one of the most important complications following cardiac surgery and is associated with increased morbidity and mortality. The condition requires inotropic support to achieve adequate hemodynamic status and tissue perfusion. While catecholamines are utilised as a standard therapy in cardiac surgery, their use is limited due to increased oxygen consumption. Levosimendan is calcium sensitising inodilatator expressing positive inotropic effect by binding with cardiac troponin C without increasing oxygen demand. Furthermore, the drug opens potassium ATP (KATP channels in cardiac mitochondria and in the vascular muscle cells, showing cardioprotective and vasodilator properties, respectively. In the past decade, levosimendan demonstrated promising results in treating patients with reduced left ventricular function when administered in peri- or post- operative settings. In addition, pre-operative use of levosimendan in patients with severely reduced left ventricular ejection fraction may reduce the requirements for postoperative inotropic support, mechanical support, duration of intensive care unit stay as well as hospital stay and a decrease in post-operative mortality. However, larger studies are needed to clarify clinical advantages of levosimendan versus conventional inotropes.

[Remote results of plastic operations on the tricuspid valve in patients with cardiac insufficiency at terminal stage].

Science.gov (United States)

Habriielian, A V; Smorzhevs'kyĭ, V I; Onishchenko, V F; Beleĭovych, V V; Topchu, Ie I; Domans'kyĭ, T M; Myroniuk, O I

2011-07-01

Comparative analysis of the results of plastic operations performance on a tricuspid valve (TV) in patients, suffering cardiac insufficiency in terminal stage, was conducted. In late postoperative period the indices of intracardial hemodynamics (cardiac output fraction, regurgitation on TV) and clinical features (severity of symptoms, quality of life) after plastic operations, using a support ring, have differed significantly from those after performance of a sutured plasty. The valve function during five years was secured in 91.1% of patients.

Travelling type monitoring and inspection device

International Nuclear Information System (INIS)

Ito, Takao; Maruki, Hideaki.

1994-01-01

The present invention sufficiently ensures video output images even if lenses of a television camera of a monitoring means are degraded to reduce the quantity of transmission light. That is, a light amount control mechanism capable of controlling the quantity of illumination light irradiated from an illumination device at an output level of a sensor of an inspection device main body. A test chart for measuring a luminance which is an output level of the sensor is disposed. During plant operation, the lenses of the television camera undergo influences of radioactivity and are degraded to reduce the quantity of transmission light on every periodical monitoring and inspection using a travelling type monitoring inspection device. In this case, the test chart disposed near the equipment to be monitored and inspected is caught by the television camera to measure a sensor output luminance. Then, the light amount control mechanism of the illumination device is controlled so as to provide a luminance which has been set at an initial stage of the plant inspection. With such procedures, video data of the objective equipment to be monitored and inspected can be obtained at a constant luminance during inspection. (I.S.)

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

Burnout versus work engagement in their effects on 24-hour ambulatory monitored cardiac autonomic function

NARCIS (Netherlands)

L.J.P. van Doornen (Lorenz); J.H. Houtveen (Jan); S. Langelaan (Saar); A.B. Bakker (Arnold); W. van Rhenen (Willem); W.B. Schaufeli (Wilmar)

2009-01-01

textabstractBurnout has been associated with increased risk of cardiovascular disease. This relationship may be mediated by a stress-related disruption in cardiac autonomic activity. The aim of the present study was to assess cardiac autonomic activity (sympathetic and parasympathetic) during a

Effects of obstructive sleep apnea on hemodynamic parameters in patients entering cardiac rehabilitation.

Science.gov (United States)

Hargens, Trent A; Aron, Adrian; Newsome, Laura J; Austin, Joseph L; Shafer, Brooke M

2015-01-01

Obstructive sleep apnea (OSA) is a prevalent form of sleep-disordered breathing. Evidence suggests that OSA may lead to cardiac remodeling, although the literature is equivocal. Previous literature suggests a high percentage of individuals entering a cardiac rehabilitation (CR) program also have OSA. The objective of this study was to determine whether resting hemodynamic variables were altered in OSA subjects entering CR compared with those without OSA, as determined by impedance cardiography. Subjects entering an early outpatient CR program were screened for OSA using an at-home screening device and verified by a sleep physician. Subjects were divided into an OSA group (n = 48) or a control group (n = 25) on the basis of the screening results. Hemodynamic variables were measured during supine rest using impedance cardiography. A 6-minute walk test was performed to assess functional capacity. The proportion of cardiac diagnoses was similar between groups. Overall, 66% of the subjects were positive for OSA. Subject groups did not differ by age, body mass index, heart rate, diastolic blood pressure, or functional capacity. Cardiac output, cardiac index, stroke volume, contractility index, and left cardiac work index were all significantly decreased in the OSA group compared with the control group (P disadvantage in recovering from their cardiac event, and place them at increased risk for secondary complications.

Fluid Overload and Cumulative Thoracostomy Output Are Associated With Surgical Site Infection After Pediatric Cardiothoracic Surgery.

Science.gov (United States)

Sochet, Anthony A; Nyhan, Aoibhinn; Spaeder, Michael C; Cartron, Alexander M; Song, Xiaoyan; Klugman, Darren; Brown, Anna T

2017-08-01

To determine the impact of cumulative, postoperative thoracostomy output, amount of bolus IV fluids and peak fluid overload on the incidence and odds of developing a deep surgical site infection following pediatric cardiothoracic surgery. A single-center, nested, retrospective, matched case-control study. A 26-bed cardiac ICU in a 303-bed tertiary care pediatric hospital. Cases with deep surgical site infection following cardiothoracic surgery were identified retrospectively from January 2010 through December 2013 and individually matched to controls at a ratio of 1:2 by age, gender, Risk Adjustment for Congenital Heart Surgery score, Society of Thoracic Surgeons-European Association for Cardiothoracic Surgery category, primary cardiac diagnosis, and procedure. None. Twelve cases with deep surgical site infection were identified and matched to 24 controls without detectable differences in perioperative clinical characteristics. Deep surgical site infection cases had larger thoracostomy output and bolus IV fluid volumes at 6, 24, and 48 hours postoperatively compared with controls. For every 1 mL/kg of thoracostomy output, the odds of developing a deep surgical site infection increase by 13%. By receiver operative characteristic curve analysis, a cutoff of 49 mL/kg of thoracostomy output at 48 hours best discriminates the development of deep surgical site infection (sensitivity 83%, specificity 83%). Peak fluid overload was greater in cases than matched controls (12.5% vs 6%; p operative characteristic curve analysis, a threshold value of 10% peak fluid overload was observed to identify deep surgical site infection (sensitivity 67%, specificity 79%). Conditional logistic regression of peak fluid overload greater than 10% on the development of deep surgical site infection yielded an odds ratio of 9.4 (95% CI, 2-46.2). Increased postoperative peak fluid overload and cumulative thoracostomy output were associated with deep surgical site infection after pediatric

[Assessment of external cardiac massage efficiency or Kouwenhoven revisited (author's transl)].

Science.gov (United States)

Berzin, B; Asseman, P; Rey, F; Thery, C; Scherpereel, P

1981-01-01

The external cardiac massage mechanism is commonly related to the ventricles compression between the vertebral block and the sternum. This over-simple explanation must be reconsidered. Following recent data, the intra thoracic pressure changes take probably a major part in it efficiency. Six patients have been studied by hemodynamic intra aortic measurements and Doppler carotidian velocimetry. Intra thoracic pressure have been recorded by an oesophageal catheter. Results are in agreement with the prominent part of the intra thoracic pressure variations. Various external cardiac methods are investigated following this monitoring. Some aspects of the classical management of the cardiac arrest have to be discussed.

Crisis management during anaesthesia: cardiac arrest.

Science.gov (United States)

Runciman, W B; Morris, R W; Watterson, L M; Williamson, J A; Paix, A D

2005-06-01

Cardiac arrest attributable to anaesthesia occurs at the rate of between 0.5 and 1 case per 10 000 cases, tends to have a different profile to that of cardiac arrest occurring elsewhere, and has an in-hospital mortality of 20%. However, as individual practitioners encounter cardiac arrest rarely, the rapidity with which the diagnosis is made and the consistency of appropriate management varies considerably. To examine the role of a previously described core algorithm "COVER ABCD-A SWIFT CHECK", supplemented by a sub-algorithm for cardiac arrest, in the management of cardiac arrest occurring in association with anaesthesia. The potential performance of this structured approach for each the relevant incidents among the first 4000 reported to the Australian Incident Monitoring Study (AIMS) was compared with the actual management as reported by the anaesthetists involved. There were 129 reports of cardiac arrest associated with anaesthesia among the first 4000 AIMS incident reports. Identified aetiological factors were grouped into five categories: (1) anaesthetic technique (11 cases with this category alone; 32 with this and one or more of the other categories, representing 25% of all 129 cardiac arrests); (2) drug related (16; 32, 25%); (3) associated with surgical procedure (9; 29, 22%); (4) associated with pre-existing medical or surgical disease (30; 82, 64%); (5) unknown (8; 14, 11%). The "real life" presentation and management of cardiac arrest in association with anaesthesia differs substantially from that detailed in general published guidelines. Cardiac rhythms at the time were sinus bradycardia (23%); asystole (22%); tachycardia/ventricular tachycardia/ventricular fibrillation (14%); and normal (7%), with a further third unknown. Details of treatment were recorded in 110 reports; modalities employed included cardiac compression (72%); adrenaline (61%); 100% oxygen (58%); atropine (38%); intravenous fluids (25%), and electrical defibrillation (17%). There

Stable xenon CT measurement of cerebral blood flow in cardiac transplantation candidates: Correlation with cognitive function

International Nuclear Information System (INIS)

Bello, J.A.; Fink, M.E.; Hilal, S.K.; Rose, E.A.; Reemtsma, K.

1987-01-01

Thirteen consecutive unselected patients with NYHA class 4 cardiac failure referred for cardiac transplantation underwent neurologic examination and cerebral blood flow measurement (rCBF) using the stable xenon enhanced CT method on a GE9800 system. Eleven men and two women were studied (mean age = 43.8 +- 6.1). On neurological examination, six of the patients demonstrated normal mental function; the remaining seven patients demonstrated memory, language, or learning impairment. There was no difference in mean cardiac output between the groups (4.9 L/min +- 1.68 vs. 4.2L/min +- 1.57). rCBF was significantly reduced in the impaired group. Cognitive impairment in patients with cardiac failure can be correlated with cerebral ischemia. Stable xenon CT measurement of rCBF in transplant candidates may help identify patients requiring more rapid transplantation to prevent permanent cerebral injury

Direct recording of cardiac output- and venous return-curves in the dog heart-lung preparation for a graphical analysis of the effects of cardioactive drugs.

Science.gov (United States)

Ishikawa, N; Taki, K; Hojo, Y; Hagino, Y; Shigei, T

1978-09-01

The dog heart-lung preparations were prepared. The "equilibrium point", which could be defined as the point at which the cardiac output (CO)-curve and the venous return (VR)-curve crossed, when the CO and VR were plotted against the right atrial pressure, was recorded directly by utilizing an X-Y recorder. The CO-curve was obtained, as a locus of the equilibrium point, by raising and lowering the level of blood in the venous reservoir (competence test). The meaning of the procedure was shown to increase or decrease the mean systemic pressure, and to cause the corresponding parallel shift in the VR-curve. The VR-curve was obtained by changing myocardial contractility. When heart failure was induced by pentobarbital or by chloroform, the equilibrium point shifted downwards to the right, depicting the VR-curve. During development of the failure, the slopes of CO-curves decreased gradually. Effects of cinobufagin and norepinephrine were also analyzed. Utilization of the X-Y recorder enabled us to settle the uniform experimental conditions more easily, and to follow the effects of drugs continuously on a diagram equating the CO- and VR-curves (Gyton's scheme).

Real-time monitoring of spinal cord blood flow with a novel sensor mounted on a cerebrospinal fluid drainage catheter in an animal model.

Science.gov (United States)

Hayatsu, Yukihiro; Kawamoto, Shunsuke; Matsunaga, Tadao; Haga, Yoichi; Saiki, Yoshikatsu

2014-10-01

The aim of our study was to develop a novel monitoring system for spinal cord blood flow (SCBF) to test the efficacy of the SCBF sensor in an animal model. The sensor system consisted of 2 optical fibers, a pedestal for fiber fixation, and a mirror for the laser reflection and was incorporated into a cerebrospinal fluid drainage catheter. In vivo studies were performed in a swine model (n=10) to measure SCBF during spinal cord ischemia induced by clamping the descending thoracic aorta and supra-aortic neck vessels, when necessary. A temporary low cardiac output model was also created by inflow clamping of the inferior vena cava to analyze the quantitative changes in SCBF during this maneuver. The developed SCBF monitoring catheter placed intrathecally could detect SCBF in all the swine. The SCBF after aortic crossclamping at the fourth intercostal level exhibited diverse changes reproducibly among the swine, with a >25% reduction in SCBF in 5 pigs, an increase in 3, and no significant changes in 2. Consistent reductions were recorded during inferior vena cava occlusion. The mean SCBF decreased by 32% after inferior vena cava occlusion when the cardiac output had decreased by 27%. We have developed a novel SCBF sensor that could detect real-time changes in spinal cord perfusion in a swine model. The device holds promise to detect imminent ischemia or ensure acceptable blood perfusion in the spinal cord and could further enhance our understanding of spinal cord circulation. Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Evaluation of left ventricular function by cardiac CT

International Nuclear Information System (INIS)

Naito, Hiroaki; Kozuka, Takahiro

1982-01-01

Left ventricular function was evaluated by CT, which was compared with the data of left ventriculography for various cardiac diseases. The end diastolic volume of the left ventricle can be readily computed from CT, with a satisfactory correlation with that of left ventriculography (r = 0.95). The left ventricular ejection fraction, calculated from the areal ratio of the left ventricular lumen in end-diastolic imaging to that in end-sytolic imaging, also roughly reflects left ventricular contractile function, but shows correlation with left ventriculography by only r = 0.79. Although the cardiac output is not sensitive for functional evaluation, it can be directly calculated by means of dynamic scanning and shows a satisfactory correlation with the ear piece pigment dilution (r = 0.85). Evaluation of left ventricular function by CT shows a high precision in comparison with left ventriculography, but still lacks temporal resolving power. (Chiba, N.)

Real-time MRI guidance of cardiac interventions.

Science.gov (United States)

Campbell-Washburn, Adrienne E; Tavallaei, Mohammad A; Pop, Mihaela; Grant, Elena K; Chubb, Henry; Rhode, Kawal; Wright, Graham A

2017-10-01

Cardiac magnetic resonance imaging (MRI) is appealing to guide complex cardiac procedures because it is ionizing radiation-free and offers flexible soft-tissue contrast. Interventional cardiac MR promises to improve existing procedures and enable new ones for complex arrhythmias, as well as congenital and structural heart disease. Guiding invasive procedures demands faster image acquisition, reconstruction and analysis, as well as intuitive intraprocedural display of imaging data. Standard cardiac MR techniques such as 3D anatomical imaging, cardiac function and flow, parameter mapping, and late-gadolinium enhancement can be used to gather valuable clinical data at various procedural stages. Rapid intraprocedural image analysis can extract and highlight critical information about interventional targets and outcomes. In some cases, real-time interactive imaging is used to provide a continuous stream of images displayed to interventionalists for dynamic device navigation. Alternatively, devices are navigated relative to a roadmap of major cardiac structures generated through fast segmentation and registration. Interventional devices can be visualized and tracked throughout a procedure with specialized imaging methods. In a clinical setting, advanced imaging must be integrated with other clinical tools and patient data. In order to perform these complex procedures, interventional cardiac MR relies on customized equipment, such as interactive imaging environments, in-room image display, audio communication, hemodynamic monitoring and recording systems, and electroanatomical mapping and ablation systems. Operating in this sophisticated environment requires coordination and planning. This review provides an overview of the imaging technology used in MRI-guided cardiac interventions. Specifically, this review outlines clinical targets, standard image acquisition and analysis tools, and the integration of these tools into clinical workflow. 1 Technical Efficacy: Stage 5 J

Ultrasonographic assessment of maternal cardiac function and peripheral circulation during normal gestation in dogs.

Science.gov (United States)

Blanco, Paula G; Tórtora, Mariana; Rodríguez, Raúl; Arias, Daniel O; Gobello, Cristina

2011-10-01

The aim of this study was to describe changes in cardiac morphology, systolic function and some peripheral hemodynamic parameters during normal pregnancy in dogs. Twenty healthy bitches, 10 pregnant (PG) and 10 non-pregnant controls (CG), were evaluated every 10 days using echocardiography from day 0 of the estrus cycle to parturition or to day 65 for the PG and CG groups, respectively. Systolic blood pressure (SBP) and uterine artery resistance index (RI) were also assessed. Throughout the study, the shortening fraction and cardiac output increased up to 30% vs. 5% (Pdogs. Copyright © 2010 Elsevier Ltd. All rights reserved.

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.

Perioperative coagulation management and blood conservation in cardiac surgery: a Canadian Survey.

Science.gov (United States)

Taneja, Ravi; Fernandes, Philip; Marwaha, Gulshan; Cheng, Davy; Bainbridge, Daniel

2008-10-01

To determine which strategies are currently used for (anti)coagulation management and blood conservation during cardiac surgery in Canada. Institutional survey. University hospital. All sites performing cardiac surgery in Canada. None. The response rate was 85%. Anticoagulation with heparin is monitored routinely through the activated coagulation time (ACT). Less than 10% of centers use heparin concentrations (Hepcon HMS, Medtronic), thromboelastography, or other point-of-care tests perioperatively. Eighty percent of centers routinely use tranexamic acid as the primary antifibrinolytic agent; however aprotinin until recently, was used more commonly for patients at increased risk for bleeding. Retrograde autologous prime is commonly used (62%); however, cell savers are uncommon for routine patients undergoing cardiac surgery (29%). Although most hospitals use a hematocrit of 20% to 21% for transfusing red blood cells, more than 50% of intensive care units do not have written guidelines for the administration of protamine, fresh frozen plasma, platelets, or factor VIIa. At least one third of centers do not audit their transfusion practices regularly. The majority of Canadian institutions do not use point-of-care tests other than ACT. Most institutions do not have algorithms for management of bleeding following cardiac surgery and at least 30% do not monitor their transfusion practice perioperatively. Cardiac surgery patients in Canada may benefit from a standardized approach to blood conservation in the perioperative period.

Acquisition, processing and display of gated cardiac scintigrams

International Nuclear Information System (INIS)

Alpert, N.M.; Chesler, D.A.; McKusick, K.A.; Potsaid, M.S.; Pohost, G.M.; Dinsmore, R.A.

1974-01-01

An improved method for non-traumatic and essentially noninvasive evaluation of left ventricular (LV) function with /sup 99m/Tc as the tracer was developed. This method combines previously used EKG gating techniques for cardiac blood pool visualization with new computerized acquisition, processing and display techniques. An Anger camera, a small computer, and a physiological synchronizer are used to acquire a sequence of eight scintigrams which span the entire cardiac cycle. Under our present protocol two twenty-minute sequences are obtained, one an LAO (50 0 ) projection, the other an RAO (30 0 ) projection. Subsequently these images are processed on-line with a digital filter to increase definition of the cardiac borders. The eight images are then displayed sequentially on a specially designed electronic monitor to give an impression of the beating heart somewhat analogous to that obtained with invasive contrast angiography

[Structure and functional organization of integrated cardiac intensive care].

Science.gov (United States)

Scherillo, Marino; Miceli, Domenico; Tubaro, Marco; Guiducci, Umberto

2007-05-01

The early invasive strategy for the treatment of acute coronary syndromes and the increasing number of older and sicker patients requiring prolonged and more complex intensive care have induced many changes in the function of the intensive care units. These changes include the statement that specially trained cardiologists and cardiac nurses who can manage patients with acute cardiac conditions should staff the intensive care units. This document indicates the structure of the units and specific recommendations for the number of beds, monitoring system, respirators, pacemaker/defibrillators and additional equipment.

The outcome of anaesthesia related cardiac arrest in a

Directory of Open Access Journals (Sweden)

O.O. Adekola

2016-07-01

Conclusion: Anaesthesia related cardiac arrest and mortality were linked to cardiovascular depression from halothane overdose in our institution. The burden can be reduced by improving on establishing standard monitoring in the perioperative period, and a team approach to patients care.

Optimizing survival outcomes for adult patients with nontraumatic cardiac arrest [digest].

Science.gov (United States)

Jung, Julianna; Zaurova, Milana

2016-10-22

Patient survival after cardiac arrest can be improved significantly with prompt and effective resuscitative care. This systematic review analyzes the basic life support factors that improve survival outcome, including chest compression technique and rapid defibrillation of shockable rhythms. For patients who are successfully resuscitated, comprehensive postresuscitation care is essential. Targeted temperature management is recommended for all patients who remain comatose, in addition to careful monitoring of oxygenation, hemodynamics, and cardiac rhythm. Management of cardiac arrest in circumstances such as pregnancy, pulmonary embolism, opioid overdose and other toxicologic causes, hypothermia, and coronary ischemia are also reviewed. [Points & Pearls is a digest of Emergency Medicine Practice].

Evaluation of Patient Radiation Dose during Cardiac Interventional Procedures: What Is the Most Effective Method?

International Nuclear Information System (INIS)

Chida, K.; Saito, H.; Ishibashi, T.; Zuguchi, M.; Kagaya, Y.; Takahashi, S.

2009-01-01

Cardiac interventional radiology has lower risks than surgical procedures. This is despite the fact that radiation doses from cardiac intervention procedures are the highest of any commonly performed general X-ray examination. Maximum radiation skin doses (MSDs) should be determined to avoid radiation-associated skin injuries in patients undergoing cardiac intervention procedures. However, real-time evaluation of MSD is unavailable for many cardiac intervention procedures. This review describes methods of determining MSD during cardiac intervention procedures. Currently, in most cardiac intervention procedures, real-time measuring of MSD is not feasible. Thus, we recommend that physicians record the patient's total entrance skin dose, such as the dose at the interventional reference point when it can be monitored, in order to estimate MSD in intervention procedures

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

Major rapid weight loss induces changes in cardiac repolarization

DEFF Research Database (Denmark)

Vedel-Larsen, Esben; Iepsen, Eva Winning; Lundgren, Julie

2016-01-01

INTRODUCTION: Obesity is associated with increased all-cause mortality, but weight loss may not decrease cardiovascular events. In fact, very low calorie diets have been linked to arrhythmias and sudden death. The QT interval is the standard marker for cardiac repolarization, but T-wave morphology...... analysis has been suggested as a more sensitive method to identify changes in cardiac repolarization. We examined the effect of a major and rapid weight loss on T-wave morphology. METHODS AND RESULTS: Twenty-six individuals had electrocardiograms (ECG) taken before and after eight weeks of weight loss......A1c (pweight loss induces changes in cardiac repolarization. Monitoring of MCS during calorie restriction makes it possible to detect repolarization changes with higher discriminative power than the QT-interval during major rapid weight...

Morphology and cardiac physiology are differentially affected by temperature in developing larvae of the marine fish mahi-mahi (Coryphaena hippurus

Directory of Open Access Journals (Sweden)

Prescilla Perrichon

2017-06-01

Full Text Available Cardiovascular performance is altered by temperature in larval fishes, but how acute versus chronic temperature exposures independently affect cardiac morphology and physiology in the growing larva is poorly understood. Consequently, we investigated the influence of water temperature on cardiac plasticity in developing mahi-mahi. Morphological (e.g. standard length, heart angle and physiological cardiac variables (e.g. heart rate fH, stroke volume, cardiac output were recorded under two conditions by imaging: (i under acute temperature exposure where embryos were reared at 25°C up to 128 h post-fertilization (hpf and then acutely exposed to 25 (rearing temperature, 27 and 30°C; and (ii at two rearing (chronic temperatures of 26 and 30°C and performed at 32 and 56 hpf. Chronic elevated temperature improved developmental time in mahi-mahi. Heart rates were 1.2–1.4-fold higher under exposure of elevated acute temperatures across development (Q10≥2.0. Q10 for heart rate in acute exposure was 1.8-fold higher compared to chronic exposure at 56 hpf. At same stage, stroke volume was temperature independent (Q10∼1.0. However, larvae displayed higher stroke volume later in stage. Cardiac output in developing mahi-mahi is mainly dictated by chronotropic rather than inotropic modulation, is differentially affected by temperature during development and is not linked to metabolic changes.

Different Modes of Monitoring and Correction of Cardiac Function During Operations Under Extracorporeal Circulation

Directory of Open Access Journals (Sweden)

L. A. Krichevsky

2007-01-01

Full Text Available Objective: to comparatively evaluate the efficiency of intensive care measures chosen on the basis of traditional monitoring of central hemodynamics (CH or on that of the data of transesophageal echocardiography (TE echoCG.Materials and methods: 50 patients were examined at coronary bypass surgery under extracorporeal circulation. Under a prospective comparative analysis were two algorithms of treatment policy: maintenance of cardiac index, by using the maximum volemic load, or that of left ventricular systolic function under guidance of transesophageal echocardiography.Results: Significantly (p<0.05 larger doses of dopamine and/or dobutamine were required to maintain adequate left ventricular systolic function. However, this treatment policy showed much better (p<0.05 circulatory parameters in the postperfusion period. At the same time the duration of postoperative inotropic therapy in these patients proved to be significantly (p<0.05 less.Conclusion. The treatment policy based on the maintenance of left ventricular systolic function under guidance of TE echoCG leads to the shortest circulatory stabilization during myocardial revascularization. The application of a volemic load and the expectant use of inotropic drugs result in a longer restoration of operated heart function. 

Halogenated anaesthetics and cardiac protection in cardiac and non-cardiac anaesthesia

Directory of Open Access Journals (Sweden)

Landoni Giovanni

2009-01-01

Full Text Available Volatile anaesthetic agents have direct protective properties against ischemic myocardial damage. The implementation of these properties during clinical anaesthesia can provide an additional tool in the treatment or prevention, or both, of ischemic cardiac dysfunction in the perioperative period. A recent meta-analysis showed that desflurane and sevoflurane reduce postoperative mortality and incidence of myocardial infarction following cardiac surgery, with significant advantages in terms of postoperative cardiac troponin release, need for inotrope support, time on mechanical ventilation, intensive care unit and overall hospital stay. Multicentre, randomised clinical trials had previously demonstrated that the use of desflurane can reduce the postoperative release of cardiac troponin I, the need for inotropic support, and the number of patients requiring prolonged hospitalisation following coronary artery bypass graft surgery either with and without cardiopulmonary bypass. The American College of Cardiology/American Heart Association Guidelines recommend volatile anaesthetic agents during non-cardiac surgery for the maintenance of general anaesthesia in patients at risk for myocardial infarction. Nonetheless, e vidence in non-coronary surgical settings is contradictory and will be reviewed in this paper together with the mechanisms of cardiac protection by volatile agents.

Applicability of a bioelectronic cardiac monitoring system for the detection of biological effects of pollution in bioindicator species in the Gulf of Finland

Science.gov (United States)

Kholodkevich, Sergey V.; Kuznetsova, Tatiana V.; Sharov, Andrey N.; Kurakin, Anton S.; Lips, Urmas; Kolesova, Natalia; Lehtonen, Kari K.

2017-07-01

Field testing of an innovative technology based on a bioelectronic cardiac monitoring system was carried out in the Gulf of Finland (Baltic Sea). The study shows that the bioelectronic system is suitable for the selected bivalve mollusks Mytilus trossulus, Macoma balthica and Anodonta anatina. Specimens taken from reference sites demonstrated a heart rate recovery time of freshwater and brackish water areas. Development of methodological basis for the testing of adaptive capacities (health) of key aquatic organisms provides new knowledge of biological effects of anthropogenic chemical stress in aquatic organisms.

Establishing a clinical cardiac MRI service

International Nuclear Information System (INIS)

O'Regan, D.P.; Schmitz, S.A.

2006-01-01

After several years of research development cardiovascular MRI has evolved into a widely accepted clinical tool. It offers important diagnostic and prognostic information for a variety of clinical indications, which include ischaemic heart disease, cardiomyopathies, valvular dysfunction and congenital heart disorders. It is a safe non-invasive technique that employs a variety of imaging sequences optimized for temporal or spatial resolution, tissue-specific contrast, flow quantification or angiography. Cardiac MRI offers specific advantages over conventional imaging techniques for a significant number of patients. The demand for cardiac MRI studies from cardiothoracic surgeons, cardiologists and other referrers is likely to continue to rise with pressure for more widespread local service provision. Setting up a cardiac MRI service requires careful consideration regarding funding issues and how it will be integrated with existing service provision. The purchase of cardiac phased array coils, monitoring equipment and software upgrades must also be considered, as well as the training needs of those involved. The choice of appropriate imaging protocols will be guided by operator experience, clinical indication and equipment capability, and is likely to evolve as the service develops. Post-processing and offline analysis form a significant part of the time taken to report studies and an efficient method of providing quantitative reports is an important requirement. Collaboration between radiologists and cardiologists is needed to develop a successful service and multi-disciplinary meetings are key component of this. This review will explore these issues from our perspective of a new clinical cardiac MRI service operating over its first year in a teaching hospital imaging department

TrustGuard: A Containment Architecture with Verified Output

Science.gov (United States)

2017-01-01

that the TrustGuard system has minimal performance decline, despite restrictions such as high communication latency and limited available bandwidth...design are the availability of high bandwidth and low delays between the host and the monitoring chip. 3-D integration provides an alternate way of...TRUSTGUARD: A CONTAINMENT ARCHITECTURE WITH VERIFIED OUTPUT SOUMYADEEP GHOSH A DISSERTATION PRESENTED TO THE FACULTY OF PRINCETON UNIVERSITY IN

Association of Total Fluid Intake and Output with Duration of Hospital Stay in Patients with Acute Pancreatitis

Directory of Open Access Journals (Sweden)

Andree H. Koop

2018-01-01

Full Text Available Background/Aims. The aim of this study was to evaluate the association of fluid balance with outcomes in patients hospitalized with acute pancreatitis (AP. Methods. This was a retrospective study of patients hospitalized between May 2008 and June 2016 with AP and a clinical order for strict recording of intake and output. Data collected included various types of fluid intake and output at 24 and 48 hours after admission. The primary outcome was length of stay (LOS. Analysis was performed using single-variable and multivariable negative binomial regression models. Results. Of 1256 patients hospitalized for AP during the study period, only 71 patients (5.6% had a clinical order for strict recording of intake and output. Increased urine output was associated with a decreased LOS at 24 and 48 hours in univariable analysis. An increasingly positive fluid balance (total intake minus urine output at 24 hours was associated with a longer LOS in multivariable analysis. Conclusions. Few patients hospitalized for AP had a documented order for strict monitoring of fluid intake and output, despite the importance of monitoring fluid balance in these patients. Our study suggests an association between urine output and fluid balance with LOS in AP.

Electrophysiological Monitoring of Brain Injury and Recovery after Cardiac Arrest

Directory of Open Access Journals (Sweden)

Ruoxian Deng

2015-10-01

Full Text Available Reliable prognostic methods for cerebral functional outcome of post cardiac-arrest (CA patients are necessary, especially since therapeutic hypothermia (TH as a standard treatment. Traditional neurophysiological prognostic indicators, such as clinical examination and chemical biomarkers, may result in indecisive outcome predictions and do not directly reflect neuronal activity, though they have remained the mainstay of clinical prognosis. The most recent advances in electrophysiological methods—electroencephalography (EEG pattern, evoked potential (EP and cellular electrophysiological measurement—were developed to complement these deficiencies, and will be examined in this review article. EEG pattern (reactivity and continuity provides real-time and accurate information for early-stage (particularly in the first 24 h hypoxic-ischemic (HI brain injury patients with high sensitivity. However, the signal is easily affected by external stimuli, thus the measurements of EP should be combined with EEG background to validate the predicted neurologic functional result. Cellular electrophysiology, such as multi-unit activity (MUA and local field potentials (LFP, has strong potential for improving prognostication and therapy by offering additional neurophysiologic information to understand the underlying mechanisms of therapeutic methods. Electrophysiology provides reliable and precise prognostication on both global and cellular levels secondary to cerebral injury in cardiac arrest patients treated with TH.

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.

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.

Glutaredoxin-2 is required to control oxidative phosphorylation in cardiac muscle by mediating deglutathionylation reactions.

Science.gov (United States)

Mailloux, Ryan J; Xuan, Jian Ying; McBride, Skye; Maharsy, Wael; Thorn, Stephanie; Holterman, Chet E; Kennedy, Christopher R J; Rippstein, Peter; deKemp, Robert; da Silva, Jean; Nemer, Mona; Lou, Marjorie; Harper, Mary-Ellen

2014-05-23

Glutaredoxin-2 (Grx2) modulates the activity of several mitochondrial proteins in cardiac tissue by catalyzing deglutathionylation reactions. However, it remains uncertain whether Grx2 is required to control mitochondrial ATP output in heart. Here, we report that Grx2 plays a vital role modulating mitochondrial energetics and heart physiology by mediating the deglutathionylation of mitochondrial proteins. Deletion of Grx2 (Grx2(-/-)) decreased ATP production by complex I-linked substrates to half that in wild type (WT) mitochondria. Decreased respiration was associated with increased complex I glutathionylation diminishing its activity. Tissue glucose uptake was concomitantly increased. Mitochondrial ATP output and complex I activity could be recovered by restoring the redox environment to that favoring the deglutathionylated states of proteins. Grx2(-/-) hearts also developed left ventricular hypertrophy and fibrosis, and mice became hypertensive. Mitochondrial energetics from Grx2 heterozygotes (Grx2(+/-)) were also dysfunctional, and hearts were hypertrophic. Intriguingly, Grx2(+/-) mice were far less hypertensive than Grx2(-/-) mice. Thus, Grx2 plays a vital role in modulating mitochondrial metabolism in cardiac muscle, and Grx2 deficiency leads to pathology. As mitochondrial ATP production was restored by the addition of reductants, these findings may be relevant to novel redox-related therapies in cardiac disease. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Mobile Cardiac Health-care Monitoring and Notification with Real Time Tachycardia and Bradycardia Arrhythmia Detection.

Science.gov (United States)

Golzar, Mina; Fotouhi-Ghazvini, Faranak; Rabbani, Hossein; Zakeri, Fahimeh Sadat

2017-01-01

The increasing trend of heart disease has turned the attention of researchers toward the use of portable connected technologies. The necessity of continuous special care for cardiovascular patients is an inevitable fact. In this research, a new wireless electrocardiographic (ECG) signal-monitoring system based on smartphone is presented. This system has two main sections. The first section consists of a sensor which receives ECG signals via an amplifier, then filters and digitizes the signal, and prepares it to be transmitted. The signals are stored, processed, and then displayed in a mobile application. The application alarms in dangerous situations and sends the location of the cardiac patient to family or health-care staff. The results obtained from the analysis of the electrocardiogram signals on 20 different people have been compared with the traditional ECG in hospital by a cardiologist. The signal is instantly transmitted by 200 sample per second to mobile phone. The raw data are processed, the anomaly is detected, and the signal is drawn on the interface in about 70 s. Therefore, the delay is not noticeable by the patient. With respect to rate of data transmission to hospital, different internet connections such as 2G, 3G, 4G, WiFi, WiMax, or Long-Term Evolution (LTE) could be used. Data transmission ranges from 9.6 kbps to 20 Mbps. Therefore, the physician could receive data with no delay. A performance accuracy of 91.62% is obtained from the wireless ECG system. It conforms to the hospital's diagnostic standard system while providing a portable monitoring anywhere at anytime.

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.)

Effects of plasma viscosity modulation on cardiac function during moderate hemodilution

Directory of Open Access Journals (Sweden)

Chatpun Surapong

2010-01-01

Full Text Available Background : Previous studies have found that increasing plasma viscosity as whole blood viscosity decrease has beneficial effects in microvascular hemodynamics. As the heart couples with systemic vascular network, changes in plasma and blood viscosity during hemodilution determine vascular pressure drop and flow rate, which influence cardiac function. This study aimed to investigate how changes in plasma viscosity affect on cardiac function during acute isovolemic hemodilution. Materials and Methods: Plasma viscosity was modulated by hemodilution of 40% of blood volume with three different plasma expanders (PEs. Dextran 2000 kDa (Dx2M, 6.3 cP and dextran 70 kDa (Dx70, 3.0 cP were used as high and moderate viscogenic PEs, respectively. Polyethylene glycol conjugated with human serum albumin (PEG-HSA, 2.2 cP was used as low viscogenic PE. The cardiac function was assessed using a miniaturized pressure-volume conductance catheter. Results: After hemodilution, pressure dropped to 84%, 79%, and 78% of baseline for Dx2M, Dx70 and PEG-HSA, respectively. Cardiac output markedly increased for Dx2M and PEG-HSA. Dx2M significantly produced higher stroke work relative to baseline and compared to Dx70. Conclusion: Acute hemodilution with PEG-HSA without increasing plasma viscosity provided beneficial effects on cardiac function compared to Dx70, and similar to those measured with Dx2M. Potentially negative effects of increasing peripheral vascular resistance due to the increase in plasma viscosity were prevented.

Temperature effects on aerobic scope and cardiac performance of European perch (Perca fluviatilis).

Science.gov (United States)

Jensen, Denise Lyager; Overgaard, Johannes; Wang, Tobias; Gesser, Hans; Malte, Hans

2017-08-01

Several recent studies have highlighted how impaired cardiac performance at high temperatures and in hypoxia may compromise the capacity for oxygen transport. Thus, at high temperatures impaired cardiac capacity is proposed to reduce oxygen transport to a degree that lowers aerobic scope and compromises thermal tolerance (the oxygen- and capacity-limited thermal tolerance (OCLTT) hypothesis). To investigate this hypothesis, we measured aerobic and cardiac performance of a eurythermal freshwater teleost, the European perch (Perca fluviatilis). Rates of oxygen consumption were measured during rest and activity at temperatures between 5°C and 27°C, and we evaluated cardiac function by in vivo measurements of heart rate and in vitro studies to determine contractility of myocardial strips. Aerobic scope increased progressively from 5°C to 21°C, after which it levelled off. Heart rate showed a similar response. We found little difference between resting and active heart rate at high temperature suggesting that increased cardiac scope during activity is primarily related to changes in stroke volume. To examine the effects of temperature on cardiac capacity, we measured isometric force development in electrically paced myocardial preparations during different combinations of temperature, pacing frequency, oxygenation and adrenergic stimulation. The force-frequency product increased markedly upon adrenergic stimulation at 21 and 27°C (with higher effects at 21°C) and the cardiac preparations were highly sensitive to hypoxia. These findings suggest that at (critically) high temperatures, cardiac output may diminish due to a decreased effect of adrenergic stimulation and that this effect may be further exacerbated if the heart becomes hypoxic. Hence cardiac limitations may contribute to the inability to increase aerobic scope at high temperatures in the European perch (Perca fluviatilis). Copyright © 2017 Elsevier Ltd. All rights reserved.

Body Size Predicts Cardiac and Vascular Resistance Effects on Men's and Women's Blood Pressure

Directory of Open Access Journals (Sweden)

Joyce M. Evans

2017-08-01

Full Text Available Key Points SummaryWe report how blood pressure, cardiac output and vascular resistance are related to height, weight, body surface area (BSA, and body mass index (BMI in healthy young adults at supine rest and standing.Much inter-subject variability in young adult's blood pressure, currently attributed to health status, may actually result from inter-individual body size differences.Each cardiovascular variable is linearly related to height, weight and/or BSA (more than to BMI.When supine, cardiac output is positively related, while vascular resistance is negatively related, to body size. Upon standing, the change in vascular resistance is positively related to size.The height/weight relationships of cardiac output and vascular resistance to body size are responsible for blood pressure relationships to body size.These basic components of blood pressure could help distinguish normal from abnormal blood pressures in young adults by providing a more effective scaling mechanism.Introduction: Effects of body size on inter-subject blood pressure (BP variability are not well established in adults. We hypothesized that relationships linking stroke volume (SV, cardiac output (CO, and total peripheral resistance (TPR with body size would account for a significant fraction of inter-subject BP variability.Methods: Thirty-four young, healthy adults (19 men, 15 women participated in 38 stand tests during which brachial artery BP, heart rate, SV, CO, TPR, and indexes of body size were measured/calculated.Results: Steady state diastolic arterial BP was not significantly correlated with any index of body size when subjects were supine. However, upon standing, the more the subject weighed, or the taller s/he was, the greater the increase in diastolic pressure. Systolic pressure strongly correlated with body weight and height both supine and standing. Diastolic and systolic BP were more strongly related to height, weight and body surface area than to body mass

Cooperative activation of cardiac transcription through myocardin bridging of paired MEF2 sites

Energy Technology Data Exchange (ETDEWEB)

Anderson, Courtney M. [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Hu, Jianxin [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Thomas, Reuben [Univ. of California, San Francisco, CA (United States). Gladstone Inst.; Gainous, T. Blair [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Celona, Barbara [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Sinha, Tanvi [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Dickel, Diane E. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Genomics Division; Heidt, Analeah B. [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Xu, Shan-Mei [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Bruneau, Benoit G. [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Univ. of California, San Francisco, CA (United States). Gladstone Inst.; Pollard, Katherine S. [Univ. of California, San Francisco, CA (United States). Gladstone Inst.; Pennacchio, Len A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Genomics Division; Black, Brian L. [Univ. of California, San Francisco, CA (United States). Cardiovascular Research Inst.; Univ. of California, San Francisco, CA (United States). Dept. of

2017-03-28

Enhancers frequently contain multiple binding sites for the same transcription factor. These homotypic binding sites often exhibit synergy, whereby the transcriptional output from two or more binding sites is greater than the sum of the contributions of the individual binding sites alone. Although this phenomenon is frequently observed, the mechanistic basis for homotypic binding site synergy is poorly understood. Here in this paper, we identify a bona fide cardiac-specific Prkaa2 enhancer that is synergistically activated by homotypic MEF2 binding sites. We show that two MEF2 sites in the enhancer function cooperatively due to bridging of the MEF2C-bound sites by the SAP domain-containing co-activator protein myocardin, and we show that paired sites buffer the enhancer from integration site-dependent effects on transcription in vivo. Paired MEF2 sites are prevalent in cardiac enhancers, suggesting that this might be a common mechanism underlying synergy in the control of cardiac gene expression in vivo.

In vitro assessment of cardiac performance after irradiation using an isolated working rat heart preparation

International Nuclear Information System (INIS)

Wondergem, J.; Laarse, A. van der; Ravels, F.J.M. van; Wermeskerken, A.-M. van; Verhoeve, H.R.; Graaf, B.W. de; Leer, J.W.H.

1991-01-01

The effect of irradiation on cardiac function was assessed using an isolated working rat heart preparation. The animals were given single doses of X-rays in the range 15-30 Gy to their hearts. Cardiac output (CO = aortic flow + coronary flow), heart weight and body weight were followed for a period of 10 months after treatment. Irradiation led to a decrease in cardiac function. This reduction was dose-dependent and progressive with time after treatment. The shape of the Frank-Starling curves constructed for irradiated hearts suggests a loss of contractile function of the myocardium. Coronary flow rates measured in 'working' hearts and in 'Langendorff' hearts were not significantly changed by the irradiation treatment. The isolated working rat heart preparation proved to be a simple and suitable animal model for the investigation of irradiation-induced cardiotoxicity. (author)

Diagnosis of traumatic cardiac contusion

International Nuclear Information System (INIS)

Waxman, K.; Soliman, M.H.; Braunstein, P.; Formosa, P.; Cohen, A.J.; Matsuura, P.; Mason, G.R.

1986-01-01

Cardiac contusion following blunt chest trauma remains a diagnostic problem because of a lack of sensitive diagnostic tests. This study evaluated thallous chloride Tl 201 single-photon-emission computed tomography in a series of 48 patients following blunt chest trauma. Of the 48 patients, 23 had normal scans. None of these patients proved to have serious arrhythmias during three days of continuous monitoring. Of 25 patients with abnormal or ambiguous studies, five (20%) developed serious arrhythmias requiring therapy. Single-photon-emission computed tomography scanning thus was sensitive in indicating that group of patients at risk of serious arrhythmias, and may therefore prove to be a useful screening test to determine the need for hospitalization and arrhythmia monitoring following blunt chest trauma

Energy Harvesting by Subcutaneous Solar Cells: A Long-Term Study on Achievable Energy Output.

Science.gov (United States)

Bereuter, L; Williner, S; Pianezzi, F; Bissig, B; Buecheler, S; Burger, J; Vogel, R; Zurbuchen, A; Haeberlin, A

2017-05-01

Active electronic implants are powered by primary batteries, which induces the necessity of implant replacement after battery depletion. This causes repeated interventions in a patients' life, which bears the risk of complications and is costly. By using energy harvesting devices to power the implant, device replacements may be avoided and the device size may be reduced dramatically. Recently, several groups presented prototypes of implants powered by subcutaneous solar cells. However, data about the expected real-life power output of subcutaneously implanted solar cells was lacking so far. In this study, we report the first real-life validation data of energy harvesting by subcutaneous solar cells. Portable light measurement devices that feature solar cells (cell area = 3.6 cm 2 ) and continuously measure a subcutaneous solar cell's output power were built. The measurement devices were worn by volunteers in their daily routine in summer, autumn and winter. In addition to the measured output power, influences such as season, weather and human activity were analyzed. The obtained mean power over the whole study period was 67 µW (=19 µW cm -2 ), which is sufficient to power e.g. a cardiac pacemaker.

Self-Powered, One-Stop, and Multifunctional Implantable Triboelectric Active Sensor for Real-Time Biomedical Monitoring.

Science.gov (United States)

Ma, Ye; Zheng, Qiang; Liu, Yang; Shi, Bojin; Xue, Xiang; Ji, Weiping; Liu, Zhuo; Jin, Yiming; Zou, Yang; An, Zhao; Zhang, Wei; Wang, Xinxin; Jiang, Wen; Xu, Zhiyun; Wang, Zhong Lin; Li, Zhou; Zhang, Hao

2016-10-12

Operation time of implantable electronic devices is largely constrained by the lifetime of batteries, which have to be replaced periodically by surgical procedures once exhausted, causing physical and mental suffering to patients and increasing healthcare costs. Besides the efficient scavenging of the mechanical energy of internal organs, this study proposes a self-powered, flexible, and one-stop implantable triboelectric active sensor (iTEAS) that can provide continuous monitoring of multiple physiological and pathological signs. As demonstrated in human-scale animals, the device can monitor heart rates, reaching an accuracy of ∼99%. Cardiac arrhythmias such as atrial fibrillation and ventricular premature contraction can be detected in real-time. Furthermore, a novel method of monitoring respiratory rates and phases is established by analyzing variations of the output peaks of the iTEAS. Blood pressure can be independently estimated and the velocity of blood flow calculated with the aid of a separate arterial pressure catheter. With the core-shell packaging strategy, monitoring functionality remains excellent during 72 h after closure of the chest. The in vivo biocompatibility of the device is examined after 2 weeks of implantation, proving suitability for practical use. As a multifunctional biomedical monitor that is exempt from needing an external power supply, the proposed iTEAS holds great potential in the future of the healthcare industry.

Microfluidic system for monitoring of cardiac (H9C2) cell proliferation

Science.gov (United States)

Kobuszewska, A.; Cwik, P.; Jastrzebska, E.; Brzozka, Z.; Chudy, M.; Renaud, P.; Dybko, A.

2017-05-01

The paper presents the application of electrical impedance spectroscopy (EIS) analysis for investigation of cardiac cell (H9C2 - rat cardiomyoblast) proliferation after verapamil hydrochloride exposure. For this purpose, two different PDMS/glass microsystems with circular microchamber and longitudinal microchannel integrated with Pt/Al electrodes were used. The microchambers were fabricated in PDMS using photolithography and replica moulding techniques. Pt/Al electrodes were fabricated on a 4-inch glass substrate using Physical Vapor Deposition (PVD). Solution of verapamil hydrochloride was continuously introduced into the microsystems with H9C2 cell culture (a flow rate of 1 μl/min) for 72 h. The impedance spectra were recorded from 100 Hz to 1 MHz. We confirmed that impedance spectroscopy can be used for non-invasive, label-free and real-time analysis of cardiac cells proliferation based on cells dielectric properties and biological structure.

PPARα-dependent increase of mouse urine output by gemfibrozil and fenofibrate.

Science.gov (United States)

Song, Danjun; Luo, Min; Dai, Manyun; Bu, Shizhong; Wang, Weihua; Zhang, Burong; Gonzalez, Frank J; Liu, Aiming

2017-02-01

While gemfibrozil and fenofibrate are prescribed for anti-dyslipidemia treatment, a rational basis for the use of these drugs for treatment of dyslipidemia with concurrent metabolic syndrome has not been established. In this study, wild-type and Pparα-null mice were fed gemfibrozil- or fenofibrate-containing diets for 14 days. Urine output (24 h) was monitored, and urine, serum, and liver and kidney tissues were subjected to toxicity assessment. A 2-month challenge followed by a 2-week wash-out was performed for gemfibrozil to determine urine output and the potential toxicity. A therapeutically equivalent dose of gemfibrozil was more effective than fenofibrate in increasing urine output. This regulatory effect was not observed in Pparα-null mice. In contrast, hepatomegaly induced by fenofibrate was more pronounced than that of gemfibrozil. No significant toxicity was observed in liver or kidney in the 2-month treatment with gemfibrozil. These data demonstrated PPARα mediates the increased urine output by fibrates. Considering the relative action on hepatomegaly and the regulatory effect on urine output, gemfibrozil may be the preferable drug to increase urine output. These results revealed a new pharmacodynamic effect of clinically prescribed PPARα agonists and suggested the potential value of gemfibrozil in modification of blood pressure.

Cardiac effects of 3-iodothyronamine: a new aminergic system modulating cardiac function.

Science.gov (United States)

Chiellini, Grazia; Frascarelli, Sabina; Ghelardoni, Sandra; Carnicelli, Vittoria; Tobias, Sandra C; DeBarber, Andrea; Brogioni, Simona; Ronca-Testoni, Simonetta; Cerbai, Elisabetta; Grandy, David K; Scanlan, Thomas S; Zucchi, Riccardo

2007-05-01

3-Iodothyronamine T1AM is a novel endogenous thyroid hormone derivative that activates the G protein-coupled receptor known as trace anime-associated receptor 1 (TAAR1). In the isolated working rat heart and in rat cardiomyocytes, T1AM produced a reversible, dose-dependent negative inotropic effect (e.g., 27+/-5, 51+/-3, and 65+/-2% decrease in cardiac output at 19, 25, and 38 microM concentration, respectively). An independent negative chronotropic effect was also observed. The hemodynamic effects of T1AM were remarkably increased in the presence of the tyrosine kinase inhibitor genistein, whereas they were attenuated in the presence of the tyrosine phosphatase inhibitor vanadate. No effect was produced by inhibitors of protein kinase A, protein kinase C, calcium-calmodulin kinase II, phosphatidylinositol-3-kinase, or MAP kinases. Tissue cAMP levels were unchanged. In rat ventricular tissue, Western blot experiments with antiphosphotyrosine antibodies showed reduced phosphorylation of microsomal and cytosolic proteins after perfusion with synthetic T1AM; reverse transcriptase-polymerase chain reaction experiments revealed the presence of transcripts for at least 5 TAAR subtypes; specific and saturable binding of [125I]T1AM was observed, with a dissociation constant in the low micromolar range (5 microM); and endogenous T1AM was detectable by tandem mass spectrometry. In conclusion, our findings provide evidence for the existence of a novel aminergic system modulating cardiac function.

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

Ultrasensitive, passive and wearable sensors for monitoring human muscle motion and physiological signals.

Science.gov (United States)

Cai, Feng; Yi, Changrui; Liu, Shichang; Wang, Yan; Liu, Lacheng; Liu, Xiaoqing; Xu, Xuming; Wang, Li

2016-03-15

Flexible sensors have attracted more and more attention as a fundamental part of anthropomorphic robot research, medical diagnosis and physical health monitoring. Here, we constructed an ultrasensitive and passive flexible sensor with the advantages of low cost, lightness and wearability, electric safety and reliability. The fundamental mechanism of the sensor is based on triboelectric effect inducing electrostatic charges on the surfaces between two different materials. Just like a plate capacitor, current will be generated while the distance or size of the parallel capacitors changes caused by the small mechanical disturbance upon it and therefore the output current/voltage will be produced. Typically, the passive sensor unambiguously monitors muscle motions including hand motion from stretch-clench-stretch, mouth motion from open-bite-open, blink and respiration. Moreover, this sensor records the details of the consecutive phases in a cardiac cycle of the apex cardiogram, and identify the peaks including percussion wave, tidal wave and diastolic wave of the radial pulse wave. To record subtle human physiological signals including radial pulsilogram and apex cardiogram with excellent signal/noise ratio, stability and reproducibility, the sensor shows great potential in the applications of medical diagnosis and daily health monitoring. Copyright © 2015 Elsevier B.V. All rights reserved.

[Factors involved in the development of vasoplegia after cardiac surgery with extracorporeal circulation. A prospective observational study].

Science.gov (United States)

Durán Bruce, M; Gomar Sancho, C; Holguera, J C; Muliterno Español, E

2014-05-01

The incidence and risk factors for vasoplegia in the early postoperative period and at 24h are investigated in patients subjected to cardiopulmonary bypass surgery. Vasoplegia following cardiac surgery with cardiopulmonary bypass is associated with a high morbimortality. The risk factors described emerged from retrospective, non-controlled studies. Observational prospective study of 188 consecutive patients subjected to cardiac surgery with cardiopulmonary bypass in a single hospital between November 2011 and May 2012. Emergency surgery or complex procedures were excluded. Vasoplegia was assessed during the immediate postoperative period, and at 24h after surgery, and was defined as a mean arterial pressure below 50mmHg, and the need for a noradrenaline perfusion of more than 0.08μg/kg/min, monitored by cardiac output and systemic vascular resistances. The anaesthetic and cardiopulmonary bypass protocols, as well as haemodynamic management, were the same in all patients. Almost half (48%) of patients had vasoplegia in the immediate postoperative period, and 34% at 24h. Risk factors for immediate vasoplegia development were preoperative use of angiotensin converting enzyme inhibitor drugs, a mean arterial pressure<50mmHg immediately after beginning cardiopulmonary bypass, duration of aortic clamping as well as the cardiopulmonary bypass, and minimum temperature in cardiopulmonary bypass. Vasoplegia at 24h after surgery was correlated to preoperative angiotensin converting enzyme inhibitor drug treatment and cardiopulmonary bypass duration. The incidence of vasoplegia after cardiac surgery with cardiopulmonary bypass is high during the first 24 postoperative hours. Preoperative treatment with angiotensin converting enzyme inhibitor and the mean arterial pressure at the beginning of cardiopulmonary bypass are the more easily controllable risk factors. In patients arriving to surgery with those drugs, treatment or prevention of vasoplejia should be planned. Copyright

Biomarkers of Cardiac Stress and Injury in Athletes: What Do They Mean?

Science.gov (United States)

Donnellan, Eoin; Phelan, Dermot

2018-04-01

Markers of myocardial stress, including troponin, creatine kinase, and brain natriuretic peptide are frequently elevated after endurance athletic pursuits. Here, we summarize the current literature pertaining to the potential mechanism of cardiac enzyme release in athletes and seek to determine the clinical implications of these findings. Recent studies have highlighted the potential adverse cardiac effects of long-term extreme endurance exercise. While troponin release occurs in a pattern distinct from ischemic damage, BNP release has been correlated with right ventricular dysfunction and is likely related to wall stress from prolonged increases in cardiac output. Higher intensity pre-race training regimes are associated with lower race-day enzyme release. While the holistic benefits of regular moderate exercise are indisputable, recent studies have raised concerns about the potential risks of extreme endurance exercise. Release of serum biomarkers suggesting myocardial damage was first described in the 1970s, yet our understanding of the implications of these findings remains incomplete. The mechanisms of release are complex but appear to be primarily physiological phenomena rather than pathologic.

e-Coaching for Intensive Cardiac Rehabilitation : a Requirement Analysis

NARCIS (Netherlands)

Nooitgedagt, A.; Beun, R.J.; Dignum, F.P.M.

2017-01-01

In this paper, the rationale and requirements are presented for an e-coaching system in the domain of intensive cardiac rehabilitation. It is argued that there is a need for a personalized program with close monitoring of the patient based on medical needs and needed lifestyle changes in a setting

Cardiac molecular-acclimation mechanisms in response to swimming-induced exercise in Atlantic salmon.

Directory of Open Access Journals (Sweden)

Vicente Castro

Full Text Available Cardiac muscle is a principal target organ for exercise-induced acclimation mechanisms in fish and mammals, given that sustained aerobic exercise training improves cardiac output. Yet, the molecular mechanisms underlying such cardiac acclimation have been scarcely investigated in teleosts. Consequently, we studied mechanisms related to cardiac growth, contractility, vascularization, energy metabolism and myokine production in Atlantic salmon pre-smolts resulting from 10 weeks exercise-training at three different swimming intensities: 0.32 (control, 0.65 (medium intensity and 1.31 (high intensity body lengths s(-1. Cardiac responses were characterized using growth, immunofluorescence and qPCR analysis of a large number of target genes encoding proteins with significant and well-characterized function. The overall stimulatory effect of exercise on cardiac muscle was dependent on training intensity, with changes elicited by high intensity training being of greater magnitude than either medium intensity or control. Higher protein levels of PCNA were indicative of cardiac growth being driven by cardiomyocyte hyperplasia, while elevated cardiac mRNA levels of MEF2C, GATA4 and ACTA1 suggested cardiomyocyte hypertrophy. In addition, up-regulation of EC coupling-related genes suggested that exercised hearts may have improved contractile function, while higher mRNA levels of EPO and VEGF were suggestive of a more efficient oxygen supply network. Furthermore, higher mRNA levels of PPARα, PGC1α and CPT1 all suggested a higher capacity for lipid oxidation, which along with a significant enlargement of mitochondrial size in cardiac myocytes of the compact layer of fish exercised at high intensity, suggested an enhanced energetic support system. Training also elevated transcription of a set of myokines and other gene products related to the inflammatory process, such as TNFα, NFκB, COX2, IL1RA and TNF decoy receptor. This study provides the first

Isometric exercise: cardiovascular responses in normal and cardiac populations.

Science.gov (United States)

Hanson, P; Nagle, F

1987-05-01

Isometric exercise produces a characteristic pressor increase in blood pressure which may be important in maintaining perfusion of muscle during sustained contraction. This response is mediated by combined central and peripheral afferent input to medullary cardiovascular centers. In normal individuals the increase in blood pressure is mediated by a rise in cardiac output with little or no change in systemic vascular resistance. However, the pressor response is also maintained during pharmacologic blockade or surgical denervation by increasing systemic vascular resistance. Left ventricular function is normally maintained or improves in normal subjects and cardiac patients with mild impairment of left ventricular contractility. Patients with poor left ventricular function may show deterioration during isometric exercise, although this pattern of response is difficult to predict from resting studies. Recent studies have shown that patients with uncomplicated myocardial infarction can perform submaximum isometric exercise such as carrying weights in the range of 30 to 50 lb without difficulty or adverse responses. In addition, many patients who show ischemic ST depression or angina during dynamic exercise may have a reduced ischemic response during isometric or combined isometric and dynamic exercise. Isometric exercises are frequently encountered in activities of daily living and many occupational tasks. Cardiac patients should be gradually exposed to submaximum isometric training in supervised cardiac rehabilitation programs. Specific job tasks that require isometric or combined isometric and dynamic activities may be evaluated by work simulation studies. This approach to cardiac rehabilitation may facilitate patients who wish to return to a job requiring frequent isometric muscle contraction. Finally, there is a need for additional research on the long-term effects of isometric exercise training on left ventricular hypertrophy and performance. The vigorous training

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.

Recommended methods for evaluating the benefits of ECUT Program outputs. [Energy Conversion and Utilization

Energy Technology Data Exchange (ETDEWEB)

Levine, L.O.; Winter, C.

1986-03-01

This study was conducted to define and develop techniques that could be used to assess the complete spectrum of positive effects resulting from the Energy Conversion and Utilization Technologies (ECUT) Program activities. These techniques could then be applied to measure the benefits from past ECUT outputs. In addition, the impact of future ECUT outputs could be assessed as part of an ongoing monitoring process, after sufficient time has elapsed to allow their impacts to develop.

Real-time system for respiratory-cardiac gating in positron tomography

International Nuclear Information System (INIS)

Klein, G.J.; Reutter, B.W.; Ho, M.H.; Huesman, R.H.; Reed, J.H.

1998-01-01

A Macintosh-based signal processing system has been developed to support simultaneous respiratory and cardiac gating on the ECAT EXACT HR PET scanner. Using the Lab-View real-time software environment, the system reads analog inputs from a pneumatic respiratory bellows and an EGG monitor to compute an appropriate histogram memory location for the PET data. Respiratory state is determined by the bellows signal amplitude; cardiac state is based on the time since the last R-wave. These two states are used in a 2D lookup table to determine a combined respiratory-cardiac state. A 4-bit address encoding the selected histogram is directed from the system to the ECAT scanner, which dynamically switches the destination of tomograph events as respiratory-cardiac state changes. to Test the switching efficiency of the combined Macintosh/ECAT system, a rotating emission phantom was built. Acquisitions with 25 msec states while the phantom was rotating at 240 rpm demonstrate the system could effectively stop motion at this rate, with approximately 5 msec switching time between states

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.

Living cardiac patch: the elixir for cardiac regeneration.

Science.gov (United States)

Lakshmanan, Rajesh; Krishnan, Uma Maheswari; Sethuraman, Swaminathan

2012-12-01

A thorough understanding of the cellular and muscle fiber orientation in left ventricular cardiac tissue is of paramount importance for the generation of artificial cardiac patches to treat the ischemic myocardium. The major challenge faced during cardiac patch engineering is to choose a perfect combination of three entities; cells, scaffolds and signaling molecules comprising the tissue engineering triad for repair and regeneration. This review provides an overview of various scaffold materials, their mechanical properties and fabrication methods utilized in cardiac patch engineering. Stem cell therapies in clinical trials and the commercially available cardiac patch materials were summarized in an attempt to provide a recent perspective in the treatment of heart failure. Various tissue engineering strategies employed thus far to construct viable thick cardiac patches is schematically illustrated. Though many strategies have been proposed for fabrication of various cardiac scaffold materials, the stage and severity of the disease condition demands the incorporation of additional cues in a suitable scaffold material. The scaffold may be nanofibrous patch, hydrogel or custom designed films. Integration of stem cells and biomolecular cues along with the scaffold may provide the right microenvironment for the repair of unhealthy left ventricular tissue as well as promote its regeneration.

Assessing quality in cardiac surgery

Directory of Open Access Journals (Sweden)

Samer A.M. Nashef

2005-07-01

Full Text Available There is a the strong temporal, if not causal, link between the intervention and the outcome in cardiac surgery and therefore a link becomes established between operative mortality and the measurement of surgical performance. In Britain the law stipulates that data collected by any public body or using public funds must be made freely available. Tools and mechanisms we devise and develop are likely to form the models on which the quality of care is assessed in other surgical and perhaps medical specialties. Measuring professional performance should be done by the profession. To measure risk there are a number of scores as crude mortality is not enough. A very important benefit of assessing the risk of death is to use this knowledge in the determination of the indication to operate. The second benefit is in the assessment of the quality of care as risk prediction gives a standard against performance of hospitals and surgeons. Peer review and “naming and shaming” are two mechanisms to monitor quality. There are two potentially damaging outcomes from the publication of results in a league-table form: the first is the damage to the hospital; the second is to refuse to operate on high-risk patients. There is a real need for quality monitoring in medicine in general and in cardiac surgery in particular. Good quality surgical work requires robust knowledge of three crucial variables: activity, risk prediction and performance. In Europe, the three major specialist societies have agreed to establish the European Cardiovascular and Thoracic Surgery Institute of Accreditation (ECTSIA. Performance monitoring is soon to become imperative. If we surgeons are not on board, we shall have no control on its final destination, and the consequences may be equally damaging to us and to our patients.

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  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 AUC ROC =0.73 [0.60-0.84], P =0.21). In the 45 patients with no arrhythmia and receiving ventilation with tidal volume AUC ROC =0.86 [0.72-0.95] vs 0.66 [0.49-0.80], P =0.02. Δ VE E'CO2 outperformed Δ VE PP, Δ VE SBP, Δ VE MBP, Δ VE FemFlow, and Δ VE HR and, during protective ventilation, arrhythmia, or both, it also outperformed Δ VE PPV. A 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

Regulation of cardiac remodeling by cardiac Na/K-ATPase isoforms

Directory of Open Access Journals (Sweden)

Lijun Catherine Liu

2016-09-01

Full Text Available Cardiac remodeling occurs after cardiac pressure/volume overload or myocardial injury during the development of heart failure and is a determinant of heart failure. Preventing or reversing remodeling is a goal of heart failure therapy. Human cardiomyocyte Na+/K+-ATPase has multiple α isoforms (1-3. The expression of the α subunit of the Na+/K+-ATPase is often altered in hypertrophic and failing hearts. The mechanisms are unclear. There are limited data from human cardiomyocytes. Abundant evidences from rodents show that Na+/K+-ATPase regulates cardiac contractility, cell signaling, hypertrophy and fibrosis. The α1 isoform of the Na+/K+-ATPase is the ubiquitous isoform and possesses both pumping and signaling functions. The α2 isoform of the Na+/K+-ATPase regulates intracellular Ca2+ signaling, contractility and pathological hypertrophy. The α3 isoform of the Na+/K+-ATPase may also be a target for cardiac hypertrophy. Restoration of cardiac Na+/K+-ATPase expression may be an effective approach for prevention of cardiac remodeling. In this article, we will overview: (1 the distribution and function of isoform specific Na+/K+-ATPase in the cardiomyocytes. (2 the role of cardiac Na+/K+-ATPase in the regulation of cell signaling, contractility, cardiac hypertrophy and fibrosis in vitro and in vivo. Selective targeting of cardiac Na+/K+-ATPase isoform may offer a new target for the prevention of cardiac remodeling.

Cardiovascular measurement and cardiac function analysis with electron beam computed tomography in health Chinese people (50 cases report)

International Nuclear Information System (INIS)

Lu Bin; Dai Ruping; Zhang Shaoxiong; Bai Hua; Jing Baolian; Cao Cheng; He Sha; Ren Li

1998-01-01

Purpose: To quantitatively measure cardiovascular diameters and function parameters by using electron beam computed tomography, EBCT. Methods: Men 50 health Chinese people accepted EBCT common transverse and short-axis enhanced movie scan (27 men, 23 women, average age 47.7 years.). The transverse scan was used to measure the diameters of the ascending aorta, descending aorta, pulmonary artery and left atrium. The movie study was used to measure the left ventricular myocardium thickness and analysis global, sectional and segmental function of the right and left ventricles. Results: The cardiovascular diameters and cardiac functional parameters were calculated. The diameters and most functional parameters (end syspoble volume, syspole volume, ejection fraction, cardiac-output, cardiac index) of normal Chinese men were greater than those of women (P>0.05). However, the EDV and MyM(myocardium mass) of both ventricles were significant (p<0.01). Conclusion: EBCT is a minimally invasive method for cardiovascular measurement and cardiac function evaluation

Hemodynamic effects of aerosol propellants. I. Cardiac depression in the dog.

Science.gov (United States)

Simaan, J A; Aviado, D M

1975-11-01

The inhalation of fluorocarbons caused a depression of myocardial contractility, aortic hypotension, a decrease in cardiac output and an increase in pulmonary vascular resistance. The minimal concentrations that elicited these changes are as follows: 1% trichlorofluoromethane (FC11); 2.5% dichlorotetrafluoroethane (FC114); and 10% dichlorodifluoromethane (FC12). Inhalation of 20% octafluorocyclobutane (FC318) and difluoroethane (FC152a) did not influence these hemodynamic parameters. As in previous comparisons, the most widely used aerosol propellants are potentially cardiotoxic in the anesthetized dog.

Monitoring pulmonary function with superimposed pulmonary gas exchange curves from standard analyzers.

Science.gov (United States)

Zar, Harvey A; Noe, Frances E; Szalados, James E; Goodrich, Michael D; Busby, Michael G

2002-01-01

A repetitive graphic display of the single breath pulmonary function can indicate changes in cardiac and pulmonary physiology brought on by clinical events. Parallel advances in computer technology and monitoring make real-time, single breath pulmonary function clinically practicable. We describe a system built from a commercially available airway gas monitor and off the shelf computer and data-acquisition hardware. Analog data for gas flow rate, O2, and CO2 concentrations are introduced into a computer through an analog-to-digital conversion board. Oxygen uptake (VO2) and carbon dioxide output (VCO2) are calculated for each breath. Inspired minus expired concentrations for O2 and CO2 are displayed simultaneously with the expired gas flow rate curve for each breath. Dead-space and alveolar ventilation are calculated for each breath and readily appreciated from the display. Graphs illustrating the function of the system are presented for the following clinical scenarios; upper airway obstruction, bronchospasm, bronchopleural fistula, pulmonary perfusion changes and inadequate oxygen delivery. This paper describes a real-time, single breath pulmonary monitoring system that displays three parameters graphed against time: expired flow rate, oxygen uptake and carbon dioxide production. This system allows for early and rapid recognition of treatable conditions that may lead to adverse events without any additional patient measurements or invasive procedures. Monitoring systems similar to the one described in this paper may lead to a higher level of patient safety without any additional patient risk.

Innovations in management of cardiac disease: drugs, treatment strategies and technology.

Science.gov (United States)

Foëx, P

2017-12-01

Within the last generation, the management of patients with heart disease has been transformed by advances in drug treatments, interventions and diagnostic technologies. The management of arterial hypertension saw beta-blockers demoted from first- to third-line treatment. Recent studies suggest that the goal of treatment may have to change to lower systolic blood pressures to prevent long-term organ damage. Today less than 15% of coronary revascularizations are surgical and more than 85% are done by interventional cardiologists inserting coronary stents. Thus, managing patients on dual antiplatelet therapy has become an important issue. With new generations of coronary stents, recommendations are changing fast. In the past, decisions concerning non-cardiac surgery after acute myocardial infarction were based on the delay between infarction and non-cardiac surgery. Today, the main concern is the patient's status in respect of dual antiplatelet therapy after primary percutaneous intervention. There have been advances in the management of heart failure but new drugs (ivabradine, sacubitril/valsartan) and cardiac resynchronization are recommended only in patients with an ejection fraction below 35% on optimal medication. Heart failure remains a major perioperative risk factor. Prospective studies have shown that troponin elevations represent myocardial injury (not necessarily myocardial infarction), are mostly silent and are associated with increased 30-day mortality. Monitoring (troponin assays) for myocardial injury in non-cardiac surgery (MINS) seems increasingly justified. The treatment of MINS needs further research. Technological advances, such as intelligent, portable monitors benefit not only patients with cardiac disease but all patients who have undergone major surgery and are on the wards postoperatively. © The Author 2017. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please

Initial Efficacy of a Cardiac Rehabilitation Transition Program: Cardiac TRUST

Science.gov (United States)

Zullo, Melissa; Boxer, Rebecca; Moore, Shirley M.

2012-01-01

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 walking and education in self-management skills to facilitate recovery following a cardiac event. Using a randomized two-group design, exercise self-efficacy, steps walked, and participation in an outpatient cardiac rehabilitation program were compared in a sample of 38 older adults; 17 who received the Cardiac TRUST program and 21 who received usual care only. At discharge from postacute care, the intervention group had a trend for higher levels of self-efficacy for exercise outcomes (X=39.1, SD=7.4) than the usual care group (X=34.5; SD=7.0) (t-test 1.9, p=.06). During the 6 weeks following discharge, compared with the usual care group, the intervention group had more attendance in out-patient cardiac rehabilitation (33% compared to 11.8%, F=7.1, p=.03) and a trend toward more steps walked during the first week (X=1,307, SD=652 compared to X=782, SD=544, t-test 1.8, p=.07). The feasibility of the intervention was better for the home health participants than for those in the skilled nursing facility and there were no safety concerns. The provision of cardiac-focused rehabilitation during postacute care has the potential to bridge the gap in transitional services from hospitalization to outpatient cardiac rehabilitation for these patients at high risk for future cardiac events. Further evidence of the efficacy of Cardiac TRUST is warranted. PMID:22084960

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.

Dynamic separation of pulmonary and cardiac changes in electrical impedance tomography

International Nuclear Information System (INIS)

Deibele, J M; Luepschen, H; Leonhardt, S

2008-01-01

In spontaneously breathing or ventilated subjects, it is difficult to image cardiac-related conductivity changes using electrical impedance tomography (EIT) due to the high amplitude of the ventilation component. Previous attempts to separate these components included either electrocardiogram-gated averaging, frequency domain filtering or holding the breath while performing the measurements. However, such methods are either not able to produce continuous real-time images or to fully separate cardiac and pulmonary changes. The aim of this work was to develop a new dynamic filtering method for the online separation of pulmonary and cardiac changes avoiding the drawbacks of the previous attempts. The approach is based on estimating template functions for the pulmonary and cardiac components by means of principal component analysis and frequency domain filtering. Then, these templates are fitted into the input signals. The new method enables an observer to examine the variation of the cardiac signal beat-by-beat after a one-time setup period of 20 s. Preliminary in vivo results of two healthy subjects are presented. The results are superior to frequency domain filtering and in good agreement with signals averaged over several cardiac cycles. The method does not depend on ECG or other a priori knowledge. The apparent validity of the method's ability to separate cardiac and pulmonary changes in EIT images was shown and has to be confirmed in future studies. The algorithm opens up new possibilities for future clinical trials on continuous monitoring by means of EIT and for the examination of the relation between the cardiac component and lung perfusion

CT-Guided Drainage of Pericardial Effusion after Open Cardiac Surgery.

Science.gov (United States)

Nour-Eldin, Nour-Eldin Abdelrehim; Alsubhi, Mohammed; Gruber-Rouh, Tatjana; Vogl, Thomas J; Kaltenbach, Benjamin; Soliman, Hazem Hamed; Hassan, Wael Eman; Abolyazid, Sherif Maher; Naguib, Nagy N

2017-08-01

This study was designed to evaluate the safety and efficacy of CT-guided drainage of the pericardial effusion in patients after cardiac surgery. The study included 128 consecutive patients (82 males, 46 females; mean age 66.6 years, SD: 4.2) complicated by pericardial effusion or hemopericardium after cardiac surgeries between June 2008 and June 2016. The medical indication for therapeutic pericardiocentesis in all patients was hemodynamic instability caused by pericardial effusion. The treatment criteria for intervention were evidence of pericardial tamponade with ejection fraction (EF) effusion was 260 ml (range 80-900 ml; standard deviation [SD]: ±70). Directly after pericardiocentesis, there was a significant improvement of the ejection fraction to 40-55% (mean: 45%; SD: ±5; p effusion drainage was 10%. The drainage was applied anteriorly (preventricular) in 39 of 128 (30.5%), retroventricularly in 33 of 128 (25.8%), and infracardiac in 56 of 128 (43.8%). Recurrence rate of pericardial effusion after removal of drains was 4.7% (67/128). Complete drainage was achieved in retroventricular and infracardiac positioning of the catheter (p effusion is a minimally invasive technique for the release of the tamponade effect of the effusion and improvement of cardiac output.

Effects of levosimendan on glomerular filtration rate, renal blood flow, and renal oxygenation after cardiac surgery with cardiopulmonary bypass: a randomized placebo-controlled study.

Science.gov (United States)

Bragadottir, Gudrun; Redfors, Bengt; Ricksten, Sven-Erik

2013-10-01

Acute kidney injury develops in a large proportion of patients after cardiac surgery because of the low cardiac output syndrome. The inodilator levosimendan increases cardiac output after cardiac surgery with cardiopulmonary bypass, but a detailed analysis of its effects on renal perfusion, glomerular filtration, and renal oxygenation in this group of patients is lacking. We therefore evaluated the effects of levosimendan on renal blood flow, glomerular filtration rate, renal oxygen consumption, and renal oxygen demand/supply relationship, i.e., renal oxygen extraction, early after cardiac surgery with cardiopulmonary bypass. Prospective, placebo-controlled, and randomized trial. Cardiothoracic ICU of a tertiary center. Postcardiac surgery patients (n=30). The patients were randomized to receive levosimendan, 0.1 µg/kg/min after a loading dose of 12 µg/kg (n=15), or placebo (n=15). The experimental procedure started 4-6 hours after surgery in the ICU during propofol sedation and mechanical ventilation. Systemic hemodynamic were evaluated by a pulmonary artery thermodilution catheter. Renal blood flow and glomerular filtration rate were measured by the renal vein retrograde thermodilution technique and by renal extraction of Cr-EDTA, respectively. Central venous pressure was kept constant by colloid/crystalloid infusion. Compared to placebo, levosimendan increased cardiac index (22%), stroke volume index (15%), and heart rate (7%) and decreased systemic vascular resistance index (21%), whereas mean arterial pressure was not affected. Levosimendan induced significant increases in renal blood flow (12%, prenal vascular resistance (18%, prenal oxygen consumption, or renal oxygen extraction, compared to placebo. After cardiac surgery with cardiopulmonary bypass, levosimendan induces a vasodilation, preferentially of preglomerular resistance vessels, increasing both renal blood flow and glomerular filtration rate without jeopardizing renal oxygenation. Due to its

Hemodynamic and regional blood flow distribution responses to dextran, hydralazine, isoproterenol and amrinone during experimental cardiac tamponade

International Nuclear Information System (INIS)

Millard, R.W.; Fowler, N.O.; Gabel, M.

1983-01-01

Four different interventions were examined in dogs with cardiac tamponade. Infusion of 216 to 288 ml saline solution into the pericardium reduced cardiac output from 3.5 +/- 0.3 to 1.7 +/- 0.2 liters/min as systemic vascular resistance increased from 4,110 +/- 281 to 6,370 +/- 424 dynes . s . cm-5. Left ventricular epicardial and endocardial blood flows were 178 +/- 13 and 220 +/- 12 ml/min per 100 g, respectively, and decreased to 72 +/- 14 and 78 +/- 11 ml/min per 100 g with tamponade. Reductions of 25 to 65% occurred in visceral and brain blood flows and in a composite brain sample. Cardiac output during tamponade was significantly increased by isoproterenol, 0.5 microgram/kg per min intravenously; hydralazine, 40 mg intravenously; dextran infusion or combined hydralazine and dextran, but not by amrinone. Total systemic vascular resistance was reduced by all interventions. Left ventricular epicardial flow was increased by isoproterenol, hydralazine and the hydralazine-dextran combination. Endocardial flow was increased by amrinone and the combination of hydralazine and dextran. Right ventricular myocardial blood flow increased with all interventions except dextran. Kidney cortical and composite brain blood flows were increased by both dextran alone and by the hydralazine-dextran combinations. Blood flow to small intestine was increased by all interventions as was that to large intestine by all except amrinone and hydralazine. Liver blood flow response was variable. The most pronounced hemodynamic and tissue perfusion improvements during cardiac tamponade were effected by combined vasodilation-blood volume expansion with a hydralazine-dextran combination. Isoproterenol had as dramatic an effect but it was short-lived. Amrinone was the least effective intervention

Testosterone receptor blockade after trauma-hemorrhage improves cardiac and hepatic functions in males.

Science.gov (United States)

Remmers, D E; Wang, P; Cioffi, W G; Bland, K I; Chaudry, I H

1997-12-01

Although studies have shown that testosterone receptor blockade with flutamide after hemorrhage restores the depressed immune function, it remains unknown whether administration of flutamide following trauma and hemorrhage and resuscitation has any salutary effects on the depressed cardiovascular and hepatocellular functions. To study this, male rats underwent a laparotomy (representing trauma) and were then bled and maintained at a mean arterial pressure (MAP) of 40 mmHg until the animals could not maintain this pressure. Ringer lactate was given to maintain a MAP of 40 mmHg until 40% of the maximal shed blood volume was returned in the form of Ringer lactate. The rats were then resuscitated with four times the shed blood volume in the form of Ringer lactate over 60 min. Flutamide (25 mg/kg) or an equal volume of the vehicle propanediol was injected subcutaneously 15 min before the end of resuscitation. Various in vivo heart performance parameters (e.g., maximal rate of the pressure increase or decrease), cardiac output, and hepatocellular function (i.e., the maximum velocity and the overall efficiency of indocyanine green clearance) were determined at 20 h after resuscitation. Additionally, hepatic microvascular blood flow (HMBF) was determined using a laser Doppler flowmeter. The results indicate that left ventricular performance, cardiac output, HMBF, and hepatocellular function decreased significantly at 20 h after the completion of trauma, hemorrhage, and resuscitation. Administration of the testosterone receptor blocker flutamide, however, significantly improved cardiac performance, HMBF, and hepatocellular function. Thus flutamide appears to be a novel and useful adjunct for improving cardiovascular and hepatocellular functions in males following trauma and hemorrhagic shock.

MicroRNA-155 attenuates late sepsis-induced cardiac dysfunction through JNK and β-arrestin 2.

Science.gov (United States)

Zhou, Yu; Song, Yan; Shaikh, Zahir; Li, Hui; Zhang, Haiju; Caudle, Yi; Zheng, Shouhua; Yan, Hui; Hu, Dan; Stuart, Charles; Yin, Deling

2017-07-18

Cardiac dysfunction is correlated with detrimental prognosis of sepsis and contributes to a high risk of mortality. After an initial hyperinflammatory reaction, most patients enter a protracted state of immunosuppression (late sepsis) that alters both innate and adaptive immunity. The changes of cardiac function in late sepsis are not yet known. MicroRNA-155 (miR-155) is previously found to play important roles in both regulations of immune activation and cardiac function. In this study, C57BL/6 mice were operated to develop into early and late sepsis phases, and miR-155 mimic was injected through the tail vein 48 h after cecal ligation and puncture (CLP). The effect of miR-155 on CLP-induced cardiac dysfunction was explored in late sepsis. We found that increased expression of miR-155 in the myocardium protected against cardiac dysfunction in late sepsis evidenced by attenuating sepsis-reduced cardiac output and enhancing left ventricular systolic function. We also observed that miR-155 markedly reduced the infiltration of macrophages and neutrophils into the myocardium and attenuated the inflammatory response via suppression of JNK signaling pathway. Moreover, overexpression of β-arrestin 2 (Arrb2) exacerbated the mice mortality and immunosuppression in late sepsis. Furthermore, transfection of miR-155 mimic reduced Arrb2 expression, and then restored immunocompetence and improved survival in late septic mice. We conclude that increased miR-155 expression through systemic administration of miR-155 mimic attenuates cardiac dysfunction and improves late sepsis survival by targeting JNK associated inflammatory signaling and Arrb2 mediated immunosuppression.

The diagnosis of anthracycline-induced cardiac damage and heart failure

Directory of Open Access Journals (Sweden)

Jarosław Dudka

2009-05-01

Full Text Available Routine examinations during chemotherapy containing anthracyclines evaluate heart function before treatment and monitor cardiotoxic effects during and after therapy. A number of methods are useful in cardiac assessment, including electrocardiography, radiology techniques (RTG, CT, MRI, PET-CT, PET-MRI, echocardiography, radioisotope imaging techniques (scyntygraphy, MUGA, PET, and ultra-structure evaluation in biopsy samples. Nevertheless, there is a continuous need for new methods to predict future damage at the initial stages of cardiac changes. In recent years the therapeutic usefulness of biochemical blood parameters in anthracycline-treated patients has been assessed. The levels of cardiac troponines (cTnI, cTnT, natriuretic peptides (ANP, BNP, and endothelin 1 have been included in the studies. Heart-type fatty acid binding protein (H-FABP is another promising factor showing cardiomyocytic impairment. However, the clinical use of biochemical parameters in diagnosing anthracycline-related cardiotoxicity is still a controversial issue.

Cardiac tumors: optimal cardiac MR sequences and spectrum of imaging appearances.

LENUS (Irish Health Repository)

O'Donnell, David H

2012-02-01

OBJECTIVE: This article reviews the optimal cardiac MRI sequences for and the spectrum of imaging appearances of cardiac tumors. CONCLUSION: Recent technologic advances in cardiac MRI have resulted in the rapid acquisition of images of the heart with high spatial and temporal resolution and excellent myocardial tissue characterization. Cardiac MRI provides optimal assessment of the location, functional characteristics, and soft-tissue features of cardiac tumors, allowing accurate differentiation of benign and malignant lesions.

Continuous and Cuffless Blood Pressure Monitoring Based on ECG and SpO2 Signals ByUsing Microsoft Visual C Sharp.

Science.gov (United States)

Younessi Heravi, M A; Khalilzadeh, M A; Joharinia, S

2014-03-01

One of the main problems especially in operating room and monitoring devices is measurement of Blood Pressure (BP) by sphygmomanometer cuff. Objective :In this study we designed a new method to measure BP changes continuously for detecting information between cuff inflation times by using vital signals in monitoring devices. This will be achieved by extraction of the time difference between each cardiac cycle and a relative pulse wave. Finger pulse and ECG signals in lead I were recorded by a monitoring device. The output of monitoring device wasinserted in a computer by serial network communication. A software interface (Microsoft Visual C#.NET ) was used to display and process the signals in the computer. Time difference between each cardiac cycle and pulse signal was calculated throughout R wave detection in ECG and peak of pulse signal by the software. The relation between time difference in two waves and BP was determined then the coefficients of equation were obtained in different physical situations. The results of estimating BP were compared with the results of sphygmomanometer method and the error rate was calculated. In this study, 25 subjects participated among them 15 were male and 10 were female. The results showed that BP was linearly related to time difference. Average of coefficient correlation was 0.9±0.03 for systolic and 0.82±0.04 for diastolic blood pressure. The highest error percentage was calculated 8% for male and 11% for female group. Significant difference was observed between the different physical situation and arm movement changes. The relationship between time difference and age was estimated in a linear relationship with a correlation coefficient of 0.76. By determining linear relation values with high accuracy, BP can be measured with insignificant error. Therefore it can be suggested as a new method to measure the blood pressure continuously.

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...

Near Infrared Spectroscopy as a Hemodynamic Monitor in Critical Illness.

Science.gov (United States)

Ghanayem, Nancy S; Hoffman, George M

2016-08-01

The objectives of this review are to discuss the technology and clinical interpretation of near infrared spectroscopy oximetry and its clinical application in patients with congenital heart disease. MEDLINE and PubMed. Near infrared spectroscopy provides a continuous noninvasive assessment of tissue oxygenation. Over 20 years ago, near infrared spectroscopy was introduced into clinical practice for monitoring cerebral oxygenation during cardiopulmonary bypass in adults. Since that time, the utilization of near infrared spectroscopy has extended into the realm of pediatric cardiac surgery and is increasingly being used in the cardiac ICU to monitor tissue oxygenation perioperatively.

Estimation of international output-energy relation. Effects of alternative output measures

International Nuclear Information System (INIS)

Shrestha, R.M.

2000-01-01

This paper analyzes the output-energy relationship with alternative measures of output and energy. Our analysis rejects the hypothesis of non-diminishing returns to energy consumption when GDP at purchasing power parities is used as the output measure unlike the case with GNP at market exchange rates. This finding also holds when energy input includes the usage of both commercial and traditional fuels. 13 refs

Levosimendan in Patients with Left Ventricular Dysfunction Undergoing Cardiac Surgery.

Science.gov (United States)

Mehta, Rajendra H; Leimberger, Jeffrey D; van Diepen, Sean; Meza, James; Wang, Alice; Jankowich, Rachael; Harrison, Robert W; Hay, Douglas; Fremes, Stephen; Duncan, Andra; Soltesz, Edward G; Luber, John; Park, Soon; Argenziano, Michael; Murphy, Edward; Marcel, Randy; Kalavrouziotis, Dimitri; Nagpal, Dave; Bozinovski, John; Toller, Wolfgang; Heringlake, Matthias; Goodman, Shaun G; Levy, Jerrold H; Harrington, Robert A; Anstrom, Kevin J; Alexander, John H

2017-05-25

Levosimendan is an inotropic agent that has been shown in small studies to prevent or treat the low cardiac output syndrome after cardiac surgery. In a multicenter, randomized, placebo-controlled, phase 3 trial, we evaluated the efficacy and safety of levosimendan in patients with a left ventricular ejection fraction of 35% or less who were undergoing cardiac surgery with the use of cardiopulmonary bypass. Patients were randomly assigned to receive either intravenous levosimendan (at a dose of 0.2 μg per kilogram of body weight per minute for 1 hour, followed by a dose of 0.1 μg per kilogram per minute for 23 hours) or placebo, with the infusion started before surgery. The two primary end points were a four-component composite of death through day 30, renal-replacement therapy through day 30, perioperative myocardial infarction through day 5, or use of a mechanical cardiac assist device through day 5; and a two-component composite of death through day 30 or use of a mechanical cardiac assist device through day 5. A total of 882 patients underwent randomization, 849 of whom received levosimendan or placebo and were included in the modified intention-to-treat population. The four-component primary end point occurred in 105 of 428 patients (24.5%) assigned to receive levosimendan and in 103 of 421 (24.5%) assigned to receive placebo (adjusted odds ratio, 1.00; 99% confidence interval [CI], 0.66 to 1.54; P=0.98). The two-component primary end point occurred in 56 patients (13.1%) assigned to receive levosimendan and in 48 (11.4%) assigned to receive placebo (adjusted odds ratio, 1.18; 96% CI, 0.76 to 1.82; P=0.45). The rate of adverse events did not differ significantly between the two groups. Prophylactic levosimendan did not result in a rate of the short-term composite end point of death, renal-replacement therapy, perioperative myocardial infarction, or use of a mechanical cardiac assist device that was lower than the rate with placebo among patients with a

Cardiac function and cognition in older community-dwelling cardiac patients.

Science.gov (United States)

Eggermont, Laura H P; Aly, Mohamed F A; Vuijk, Pieter J; de Boer, Karin; Kamp, Otto; van Rossum, Albert C; Scherder, Erik J A

2017-11-01

Cognitive deficits have been reported in older cardiac patients. An underlying mechanism for these findings may be reduced cardiac function. The relationship between cardiac function as represented by different echocardiographic measures and different cognitive function domains in older cardiac patients remains unknown. An older (≥70 years) heterogeneous group of 117 community-dwelling cardiac patients under medical supervision by a cardiologist underwent thorough echocardiographic assessment including left ventricular ejection fraction, cardiac index, left atrial volume index, left ventricular mass index, left ventricular diastolic function, and valvular calcification. During a home visit, a neuropsychological assessment was performed within 7.1 ± 3.8 months after echocardiographic assessment; the neuropsychological assessment included three subtests of a word-learning test (encoding, recall, recognition) to examine one memory function domain and three executive function tests, including digit span backwards, Trail Making Test B minus A, and the Stroop colour-word test. Regression analyses showed no significant linear or quadratic associations between any of the echocardiographic functions and the cognitive function measures. None of the echocardiographic measures as representative of cardiac function was correlated with memory or executive function in this group of community-dwelling older cardiac patients. These findings contrast with those of previous studies. © 2017 Japanese Psychogeriatric Society.

Cardiac autonomic modulation by estrogen in female mice undergoing ambulatory monitoring and in vivo electrophysiologic testing.

Science.gov (United States)

Saba, Samir; Shusterman, Vladimir; Usiene, Irmute; London, Barry

2004-04-01

Estrogen is an important modulator of cardiovascular risk, but its mechanism of action is not fully understood. We investigated the effect of ovariectomy and its timing on the cardiac electrophysiology in mice. Thirty female mice (age 18.8 +/- 3.1 weeks) underwent in vivo electrophysiologic testing before and after autonomic blockade. Fifteen mice were ovariectomized prepuberty (PRE) and ten postpuberty (POST), 2 weeks prior to electrophysiologic testing. Five age-matched sham-operated female mice (Control) served as controls. A subset of 13 mice (5 PRE, 3 POST, and 5 Controls) underwent 24-hour ambulatory monitoring. With ambulatory monitoring, the average (668 +/- 28 vs 769 +/- 52 b/min, P = 0.008) and minimum (485 +/- 47 vs 587 +/- 53 b/min, P = 0.02) heart rates were significantly slower in the ovariectomized mice (PRE and POST groups) compared to the Control group. At baseline electrophysiologic testing, there were no significant differences among the ovariectomized and intact mice in any of the measured parameters. With autonomic blockade, the Control group had a significantly larger change (delta) in the atrioventricular (AV) nodal Wenckebach (AVW) periodicity (deltaAVW = 11.3 +/- 2.9 vs 2.1 +/- 7.3 ms, P = 0.05) and functional refractory period (deltaFRP = 11.3 +/- 2.1 vs 1.25 +/- 6.8 ms, P = 0.02) compared to the ovariectomized mice. These results were not altered by the time of ovariectomy (PRE vs POST groups). Our results suggest that estrogen modulates the autonomic inputs into the murine sinus and AV nodes. These findings, if replicated in humans, might underlie the observed clustering of certain arrhythmias around menstruation and explain the higher incidence of arrhythmias in men and postmenopausal women.

Cardiac function and cognition in older community-dwelling cardiac patients

NARCIS (Netherlands)

Eggermont, Laura H.P.; Aly, Mohamed F.A.; Vuijk, Pieter J.; de Boer, Karin; Kamp, Otto; van Rossum, Albert C.; Scherder, Erik J.A.

2017-01-01

Background: Cognitive deficits have been reported in older cardiac patients. An underlying mechanism for these findings may be reduced cardiac function. The relationship between cardiac function as represented by different echocardiographic measures and different cognitive function domains in older

Preliminary Retrospective Analysis of Daily Tomotherapy Output Constancy Checks Using Statistical Process Control.

Science.gov (United States)

Mezzenga, Emilio; D'Errico, Vincenzo; Sarnelli, Anna; Strigari, Lidia; Menghi, Enrico; Marcocci, Francesco; Bianchini, David; Benassi, Marcello

2016-01-01

The purpose of this study was to retrospectively evaluate the results from a Helical TomoTherapy Hi-Art treatment system relating to quality controls based on daily static and dynamic output checks using statistical process control methods. Individual value X-charts, exponentially weighted moving average charts, and process capability and acceptability indices were used to monitor the treatment system performance. Daily output values measured from January 2014 to January 2015 were considered. The results obtained showed that, although the process was in control, there was an out-of-control situation in the principal maintenance intervention for the treatment system. In particular, process capability indices showed a decreasing percentage of points in control which was, however, acceptable according to AAPM TG148 guidelines. Our findings underline the importance of restricting the acceptable range of daily output checks and suggest a future line of investigation for a detailed process control of daily output checks for the Helical TomoTherapy Hi-Art treatment system.

Cardiac rhythm disturbance in athletes with cardiac connective tissue dysplasia syndrome

Directory of Open Access Journals (Sweden)

Shahrjerdi Sh

2007-06-01

Full Text Available Background: Cardiac connective tissue dysplasia syndrome consists of mitral valve prolapse (MVP, anomalously located chordae tendinae of the left ventricle, or a combination of the two. MVP is marked by the displacement of an abnormally thickened mitral valve leaflet into the left atrium during systole. The nonclassic form of MVP carries a low risk of complications. Patients with severe classic MVP can suffer from mitral regurgitation (MR, infective endocarditis, and, infrequently, sudden death from cardiac arrest. Anomalously located left ventricular chordae tendinae are fibrous or fibromuscular bands that stretch across the left ventricle from the septum to the free wall. They have been associated with murmurs and arrhythmias. The purpose of this study is to assess the performance, as measured by the physical working capacity (PWC170 and maximal oxygen consumption (VO2 max, in athletes with cardiac connective tissue dysplasia syndrome. Methods: Of the 183 male athletes studied, 158 had cardiac connective tissue dysplasia syndrome and 25 were normal, healthy controls. Their mean age was 16.23 (± 5.48 years and mean training time was 5.2 (±- 4.6 years. Athletes with cardiac connective tissue dysplasia syndrome were divided to four groups. Group 1 consisted of those with MVP; Group 2 had patients with an additional cord in left ventricle; Group 3 was made up of athletes with a combination of MVP and additional cord; Group 4 contained athletes with a combination of MVP and MR. All sportsmen were studied by echocardiograph, veloergometer, and those with arrhythmias were studied and recorded using a Holter monitor. Results: The most common form of this syndrome in our study groups was MVP. The PWC170and VO2 max among the athletes with the combination of MVP+MR (Group 4 was lower than that of athletes in other groups (P<0.05. The most common arrhythmia among the athletes with anomalously located left ventricular chordae, Group 2, was Wolf

Correlação entre gasometria atrial direita e índice cardíaco no pós-operatório de cirurgia cardíaca Correlation between right atrial venous blood gasometry and cardiac index in cardiac surgery postoperative period

Directory of Open Access Journals (Sweden)

João Jackson Duarte

2010-06-01

( a-v O2. Afterwards, these parameters were compared with the cardiac index determined by thermodilution. RESULTS: There was good correlation between SvO2, C(avO2 of the venous right atrial blood and cardiac index meansured by termodiluition method, with sensibility and especificity good and high positive predict value and negative predict value. The PvO2 demonstrated poor sensibility in the estimative of low output. CONCLUSION: In cardiac surgery postoperative, the SvO2and the C(a-vO2 were safe parameters correlated with low cardiac output. The PvO2 demonstrated poor sensibility in the estimative of low output in postoperative cardiac surgery.

Input-output supervisor; Le superviseur d'entree-sortie dans les ordinateurs

Energy Technology Data Exchange (ETDEWEB)

Dupuy, R [Commissariat a l' Energie Atomique, Vaujours (France). Centre d' Etudes Nucleaires

1970-07-01

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) [French] Le superviseur d'entree-sortie est le programme charge de gerer les echanges d'information entre la memoire rapide et les organes peripheriques d'un ordinateur. Ce travail se compose de trois parties: 1 - Etude d'un systeme d'entree-sortie general et theorique qui, en faisant un certain nombre d'hypotheses simplificatrices, permet de retrouver la plupart des superviseurs d'entree-sortie actuels. 2 - Expose d'une realisation concrete, gestion d'un tambour magnetique. 3 - Suggestions hardware en vue de faciliter le timesharing. (auteur)

PGC-1α accelerates cytosolic Ca2+ clearance without disturbing Ca2+ homeostasis in cardiac myocytes

International Nuclear Information System (INIS)

Chen, Min; Wang, Yanru; Qu, Aijuan

2010-01-01

Energy metabolism and Ca 2+ handling serve critical roles in cardiac physiology and pathophysiology. Peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) is a multi-functional coactivator that is involved in the regulation of cardiac mitochondrial functional capacity and cellular energy metabolism. However, the regulation of PGC-1α in cardiac Ca 2+ signaling has not been fully elucidated. To address this issue, we combined confocal line-scan imaging with off-line imaging processing to characterize calcium signaling in cultured adult rat ventricular myocytes expressing PGC-1α via adenoviral transduction. Our data shows that overexpressing PGC-1α improved myocyte contractility without increasing the amplitude of Ca 2+ transients, suggesting that myofilament sensitivity to Ca 2+ increased. Interestingly, the decay kinetics of global Ca 2+ transients and Ca 2+ waves accelerated in PGC-1α-expressing cells, but the decay rate of caffeine-elicited Ca 2+ transients showed no significant change. This suggests that sarcoplasmic reticulum (SR) Ca 2+ -ATPase (SERCA2a), but not Na + /Ca 2+ exchange (NCX) contribute to PGC-1α-induced cytosolic Ca 2+ clearance. Furthermore, PGC-1α induced the expression of SERCA2a in cultured cardiac myocytes. Importantly, overexpressing PGC-1α did not disturb cardiac Ca 2+ homeostasis, because SR Ca 2+ load and the propensity for Ca 2+ waves remained unchanged. These data suggest that PGC-1α can ameliorate cardiac Ca 2+ cycling and improve cardiac work output in response to physiological stress. Unraveling the PGC-1α-calcium handing pathway sheds new light on the role of PGC-1α in the therapy of cardiac diseases.

Cardiac autonomic profile in different sports disciplines during all-day activity.

Science.gov (United States)

Sztajzel, J; Jung, M; Sievert, K; Bayes De Luna, A

2008-12-01

Physical training and sport activity have a beneficial effect on cardiac autonomic activity. However, the exact impact of different types of sports disciplines on cardiac autonomic function is still unclear. The aim of this study was to evaluate the cardiac autonomic profile in different sports discplines and to determine their impact on cardiac autonomic function by using heart rate variability (HRV), a noninvasive electrocardiographic (ECG) analysis of the sympatho-vagal balance. Temporal and spectral HRV parameters determined from 24-hour continuous ECG monitoring were studied in 40 subjects, including 12 endurance athletes, 14 hockey players and 14 untrained male volunteers (control group). Each participant had to wear a Holter recorder during 24 hours and to continue his everyday activities. All HRV parameters were compared between the 3 study groups. All heart rate values were lower and all parasympathetic-related time domain indices, including root mean square of successive differences (RMSSD) and pNN50 (NN50 count divided by the total number of all NN intervals), were higher in both athletes groups as compared with controls (PHRV, were significantly higher only in endurance athletes (PHRV (higher SDNN), indicating thereby that this type sports discipline may have a more substantially favorable effect on the cardiac autonomic profile.

The Correlation of Skeletal and Cardiac Muscle Dysfunction in Duchenne Muscular Dystrophy.

Science.gov (United States)

Posner, Andrew D; Soslow, Jonathan H; Burnette, W Bryan; Bian, Aihua; Shintani, Ayumi; Sawyer, Douglas B; Markham, Larry W

2016-01-01

Duchenne muscular dystrophy (DMD) is characterized by progressive skeletal muscle and cardiac dysfunction. While skeletal muscle dysfunction precedes cardiomyopathy, the relationship between the progressive decline in skeletal and cardiac muscle function is unclear. This relationship is especially important given that the myocardial effects of many developing DMD therapies are largely unknown. Our objective was to assess the relationship between progression of skeletal muscle weakness and onset of cardiac dysfunction in DMD. A total of 77 DMD subjects treated at a single referral center were included. Demographic information, quantitative muscle testing (QMT), subjective muscle strength, cardiac function, and current and retrospective medications were collected. A Spearman rank correlation was used to evaluate for an association between subjective strength and fractional shortening. The effects of total QMT and arm QMT on fractional shortening were examined in generalized least square with and without adjustments for age, ambulatory status, and duration of corticosteroids and cardiac specific medications. We found a significant correlation between maintained subjective skeletal muscle arm and leg strength and maintained cardiac function as defined by fractional shortening (rho=0.47, p=0.004 and rho=0.48, p=0.003, respectively). We also found a significant association between QMT and fractional shortening among non-ambulatory DMD subjects (p=0.03), while this association was not significant in ambulatory subjects. Our findings allow us to conclude that in this population, there exists a significant relationship between skeletal muscle and cardiac function in non-ambulatory DMD patients. While this does not imply a causal relationship, a possible association between skeletal and cardiac muscle function suggests that researchers should carefully monitor cardiac function, even when the primary outcome measures are not cardiac in nature.

Noninvasive continuous blood pressure monitoring by the ClearSight system during robot-assisted laparoscopic radical prostatectomy.

Science.gov (United States)

Sakai, Yoko; Yasuo M, Tsutsumi; Oyama, Takuro; Murakami, Chiaki; Kakuta, Nami; Tanaka, Katsuya

2018-01-01

Robot-assisted laparoscopic radical prostatectomy (RALRP) is commonly performed in the surgical treatment of prostate cancer. However, the steep Trendelenburg position (25) and pneumoperitoneum required for this procedure can sometimes cause hemodynamic changes. Although blood pressure is traditionally monitored invasively during RALRP, the ClearSight system (BMEYE, Amsterdam, The Netherlands) enables a totally noninvasive and simple continuous blood pressure and cardiac output monitoring based on finger arterial pressure pulse contour analysis. We therefore investigated whether noninvasive continuous arterial blood pressure measurements using the ClearSight system were comparable to those obtained invasively in patients undergoing RALRP. Ten patients scheduled for RALRP with American Society of Anesthesiologists physical status I-II were included in this study. At each of the seven defined time points, noninvasive and invasive blood pressure measurements were documented and compared in each patient using Bland-Altman analysis. Although the blood pressure measured with the ClearSight system correlated with that measured invasively, a large difference between the values obtained by the two devices was noted. The ClearSight system was unable to detect blood pressure accurately during RALRP, suggesting that blood pressure monitoring using this device alone is not feasible in this small patient population. J. Med. Invest. 65:69-73, February, 2018.

Cardiac risk assessment before carotid endarterectomy

International Nuclear Information System (INIS)

Rabee, Hussein M.M.

2000-01-01

Preoperative cardiac assessment is an essential step to identify the patients at risk, optimize any dysfunction, anticipate perioperative and postoperative problems and plan special management. Carotid endarterectomy (CEA) has become one of the most commonly performed vascular procedures in Western countries. The awareness of the potential beneficial role and hazards of CEA is not proportionate to the magnitude of this problem in our countries, not only among patients, but also among the medical disciplines. This report is a retrospective analysis of the prevalence of coronary artery diseases among 442 patients who were referred to the Division of Vascular Surgery at the King Khalid University Hospital in Riyadh, Saudi Arabia with suspicion of carotid artery disease. Eighty-two patients proved to have significant carotid artery stenosis and had thorough preoperative cardiac assessment by senior cardiologist. All cases had clinical assessment and ECG, 66 cases had echocardiogram examination, 44 had Dipyridamole Thallium-scan and 12 had coronary angiogram. Sixty-eight patients underwent 76 carotid endarterectomy. Four of them had MI and only one case died during preoperative period. This study shows that cardiac screening studies have a potential role in the candidates for carotid surgery in influencing the decision to operate and intensify of perioperative monitoring and care. We believe that the teamwork should involve vascular surgeons, cardiologist and anesthetist to manage such critical patients properly. (author)

Multimodality assessment of cardiac involvement in Churg-Strauss syndrome patients in clinical remission

International Nuclear Information System (INIS)

Szczeklik, W.; Miszalski-Jamka, T.; Mastalerz, L.; Sokolowska, B.; Dropinski, J.; Musial, J.; Banys, R.; Hor, K.N.; Mazur, W.

2011-01-01

Cardiac involvement in Churg-Strauss syndrome (CSS) is not uncommon, but its frequency varies widely and may depend on the activity of the disease. Therefore, the cardiac involvement in CSS patients in clinical remission was assessed in the present study. In 20 CSS patients in remission and 20 sex- and age-matched healthy controls, an electrocardiogram (ECG) stress test, echocardiography, and 24-h ECG Holter monitoring were performed, together with cardiac magnetic resonance imaging (cMRI). Cardiac involvement was present in 90% (18/20) of CSS patients. Left ventricular ejection fraction (LVEF) was on average lower in the CSS group than in controls (P<0.05), with 7 patients showing systolic heart failure (LVEF <50%). cMRI changes included late gadolinium enhancement lesions in the LV in 89% of patients (17/19), present in all layers of the myocardium. Signs of ongoing inflammation (early gadolinium enhancement) and edema (T2-weighted imaging) were present in 6/19 patients. Holter monitoring revealed both supraventricular and ventricular arrhythmias more frequently in CSS patients when compared with controls (P<0.05). Absolute eosinophil count before the initiation of treatment was higher in rhythm disturbances (P<0.05), and inversely correlated with LV systolic function (rho -0.65). Heart involvement in CSS patients who are in clinical remission is very common. It is characterized not only by fibrosis, but also by an active inflammatory process. The latter finding might influence therapeutic decisions in CSS patients in full clinical remission. (author)

Multimodality assessment of cardiac involvement in Churg-Strauss syndrome patients in clinical remission

Energy Technology Data Exchange (ETDEWEB)

Szczeklik, W; Miszalski-Jamka, T; Mastalerz, L; Sokolowska, B; Dropinski, J; Musial, J [Medical Coll., Jagiellonian Univ., Krakow (Poland); Banys, R [John Paul II Hospital, Krakow (Poland); Hor, K N [Cincinnati Children' s Medical Center, OH (United States); Mazur, W [Heart and Vascular Center at The Christ Hospitals, OH (United States)

2011-02-15

Cardiac involvement in Churg-Strauss syndrome (CSS) is not uncommon, but its frequency varies widely and may depend on the activity of the disease. Therefore, the cardiac involvement in CSS patients in clinical remission was assessed in the present study. In 20 CSS patients in remission and 20 sex- and age-matched healthy controls, an electrocardiogram (ECG) stress test, echocardiography, and 24-h ECG Holter monitoring were performed, together with cardiac magnetic resonance imaging (cMRI). Cardiac involvement was present in 90% (18/20) of CSS patients. Left ventricular ejection fraction (LVEF) was on average lower in the CSS group than in controls (P<0.05), with 7 patients showing systolic heart failure (LVEF <50%). cMRI changes included late gadolinium enhancement lesions in the LV in 89% of patients (17/19), present in all layers of the myocardium. Signs of ongoing inflammation (early gadolinium enhancement) and edema (T2-weighted imaging) were present in 6/19 patients. Holter monitoring revealed both supraventricular and ventricular arrhythmias more frequently in CSS patients when compared with controls (P<0.05). Absolute eosinophil count before the initiation of treatment was higher in rhythm disturbances (P<0.05), and inversely correlated with LV systolic function (rho -0.65). Heart involvement in CSS patients who are in clinical remission is very common. It is characterized not only by fibrosis, but also by an active inflammatory process. The latter finding might influence therapeutic decisions in CSS patients in full clinical remission. (author)

The effect of endogenously released glucose, insulin, glucagon-like peptide 1, ghrelin on cardiac output, heart rate, stroke volume, and blood pressure.

Science.gov (United States)

Hlebowicz, Joanna; Lindstedt, Sandra; Björgell, Ola; Dencker, Magnus

2011-12-29

Ingestion of a meal increases the blood flow to the gastrointestinal organs and affects the heart rate (HR), blood pressure and cardiac output (CO), although the mechanisms are not known. The aim of this study was to evaluate the effect of endogenously released glucose, insulin, glucagon-like peptide 1 (GLP-1), ghrelin on CO, HR, stroke volume (SV), and blood pressure. Eleven healthy men and twelve healthy women ((mean ± SEM) aged: 26 ± 0.2 y; body mass index: 21.8 ± 0.1 kg/m(2))) were included in this study. The CO, HR, SV, systolic and diastolic blood pressure, antral area, gastric emptying rate, and glucose, insulin, GLP-1 and ghrelin levels were measured. The CO and SV at 30 min were significantly higher, and the diastolic blood pressure was significantly lower, than the fasting in both men and women (P blood pressure (P = 0.021, r = -0.681), and the change in SV (P = 0.008, r = -0.748) relative to the fasting in men. The insulin 0-30 min AUC was significantly correlated to the CO 0-30 min AUC (P = 0.002, r = 0.814) in men. Significant correlations were also found between the 0-120 min ghrelin and HR AUCs (P = 0.007, r = 0.966) in men. No statistically significant correlations were seen in women. Physiological changes in the levels of glucose, insulin, GLP-1 and ghrelin may influence the activity of the heart and the blood pressure. There may also be gender-related differences in the haemodynamic responses to postprandial changes in hormone levels. The results of this study show that subjects should not eat immediately prior to, or during, the evaluation of cardiovascular interventions as postprandial affects may affect the results, leading to erroneous interpretation of the cardiovascular effects of the primary intervention. NCT01027507.

Effects of levosimendan on mortality in patients undergoing cardiac surgery: A systematic review and meta-analysis.

Science.gov (United States)

Chen, Peili; Wu, Xiaoqiang; Wang, Zhiwei; Li, Zhenya; Tian, Xiangyong; Wang, Junpeng; Yan, Tianzhong

2018-06-01

We sought to determine the impact of levosimendan on mortality following cardiac surgery based on large-scale randomized controlled trials (RCTs). We searched PubMed, Web of Science, Cochrane databases, and ClinicalTrials.gov for RCTs published up to December 2017, on levosimendan for patients undergoing cardiac surgery. A total of 25 RCTs enrolling 2960 patients met the inclusion criteria; data from 15 placebo-controlled randomized trials were included for meta-analysis. Pooled analysis showed that the all-cause mortality rate was 6.4% (71 of 1106) in the levosimendan group and 8.4% (93 of 1108) in the placebo group (odds ratio [OR], 0.76; 95% confidence interval [CI], 0.55-1.04; P = 0.09). There were no significant differences between the two groups in the rates of myocardial infarction (OR: 0.91; 95% CI, 0.68-1.21; P = 0.52), serious adverse events (OR: 0.84; 95% CI, 0.66-1.07; P = 0.17), hypotension (OR: 1.69; 95% CI, 0.94-3.03; P = 0.08), and low cardiac output syndrome (OR: 0.47; 95% CI, 0.22-1.02; P = 0.05). Levosimendan did not result in a reduction in mortality in adult cardiac surgery patients. Well designed, adequately powered, multicenter trials are necessary to determine the role of levosimendan in adult cardiac surgery. © 2018 The Authors. Journal of Cardiac Surgery Published by Wiley Periodicals Inc.

Perceiving imitatible stimuli: consequences of isomorphism between input and output.

Science.gov (United States)

Wilson, M

2001-07-01

For more than a century, psychologists have been intrigued by the idea that mental representations of perceived human actions are closely connected with mental representations of performing those same actions. In this article, connections between input and output representations are considered in terms of the potential for imitation. A broad range of evidence suggests that, for imitatible stimuli, input and output representations are isomorphic to one another, allowing mutual influence between perception and motoric planning that is rapid, effortless, and possibly obligatory. Thus, the cognitive consequences of imitatibility may underlie such diverse phenomena as phoneme perception; imitation in neonates; echoic memory; stimulus-response compatibility; conduction aphasia; maintenance rehearsal; and a variety of developmental and social activities such as language acquisition, social learning, empathy, and monitoring one's own behavior.

Is it time for cardiac innervation imaging?

Energy Technology Data Exchange (ETDEWEB)

Knuuti, J. [Turku Univ., Turku (Finland) Turku PET Center; Sipola, P. [Kuopio Univ., Kuopio (Finland)

2005-03-01

The autonomic nervous system plays an important role in the regulation of cardiac function and the regional distribution of cardiac nerve terminals can be visualized using scintigraphic techniques. The most commonly used tracer is iodine-123-metaiodobenzylguanidine (MIBG) but C-11-hydroxyephedrine has also been used with PET. When imaging with MIBG, the ratio of heart-to-mediastinal counts is used as an index of tracer uptake, and regional distribution is also assessed from tomographic images. The rate of clearance of the tracer can also be measured and indicates the function of the adrenergic system. Innervation imaging has been applied in patients with susceptibility to arrythmias, coronary artery disease, hypertrophic and dilated cardiomyopathy and anthracycline induced cardiotoxicity. Abnormal adrenergic innervation or function appear to exist in many pathophysiological conditions indicating that sympathetic neurons are very susceptible to damage. Abnormal findings in innervation imaging also appear to have significant prognostic value especially in patients with cardiomyopathy. Recently, it has also been shown that innervation imaging can monitor drug-induced changes in cardiac adrenergic activity. Although innervation imaging holds great promise for clinical use, the method has not received wider clinical acceptance. Larger randomized studies are required to confirm the value of innervation imaging in various specific indications.

The reliability and validity of passive leg raise and fluid bolus to assess fluid responsiveness in spontaneously breathing emergency department patients

DEFF Research Database (Denmark)

Duus, Nicolaj; Shogilev, Daniel J; Skibsted, Simon

2015-01-01

PURPOSE: We investigated the reproducibility of passive leg raise (PLR) and fluid bolus (BOLUS) using the Non-Invasive Cardiac Output Monitor (NICOM; Cheetah Medical, Tel Aviv, Israel) for assessment of fluid responsiveness (FR) in spontaneously breathing emergency department (ED) patients. METHODS...

Basal Ganglia Outputs Map Instantaneous Position Coordinates during Behavior

Science.gov (United States)

Barter, Joseph W.; Li, Suellen; Sukharnikova, Tatyana; Rossi, Mark A.; Bartholomew, Ryan A.

2015-01-01

The basal ganglia (BG) are implicated in many movement disorders, yet how they contribute to movement remains unclear. Using wireless in vivo recording, we measured BG output from the substantia nigra pars reticulata (SNr) in mice while monitoring their movements with video tracking. The firing rate of most nigral neurons reflected Cartesian coordinates (either x- or y-coordinates) of the animal's head position during movement. The firing rates of SNr neurons are either positively or negatively correlated with the coordinates. Using an egocentric reference frame, four types of neurons can be classified: each type increases firing during movement in a particular direction (left, right, up, down), and decreases firing during movement in the opposite direction. Given the high correlation between the firing rate and the x and y components of the position vector, the movement trajectory can be reconstructed from neural activity. Our results therefore demonstrate a quantitative and continuous relationship between BG output and behavior. Thus, a steady BG output signal from the SNr (i.e., constant firing rate) is associated with the lack of overt movement, when a stable posture is maintained by structures downstream of the BG. Any change in SNr firing rate is associated with a change in position (i.e., movement). We hypothesize that the SNr output quantitatively determines the direction, velocity, and amplitude of voluntary movements. By changing the reference signals to downstream position control systems, the BG can produce transitions in body configurations and initiate actions. PMID:25673860

Rationale and design of the Pan-African Sudden Cardiac Death survey

DEFF Research Database (Denmark)

Bonny, Aimé; Ngantcha, Marcus; Amougou, Sylvie Ndongo

2014-01-01

BACKGROUND: The estimated rate of sudden cardiac death (SCD) in Western countries ranges from 300,000 to 400,000 annually, which represents 0.36 to 1.28 per 1 000 inhabitants in Europe and the United States. The burden of SCD in Africa is unknown. Our aim is to assess the epidemiology of SCD...... of districts of interest will be checked for past medical history, circumstances of death, and autopsy report (if possible). We will also analyse the employment of resuscitation attempts during the time frame of sudden cardiac arrest (SCA) in various patient populations throughout African countries. CONCLUSION...... in Africa. METHODS: The Pan-Africa SCD study is a prospective, multicentre, community-based registry monitoring all cases of cardiac arrest occurring in victims over 15 years old. We will use the definition of SCD as 'witnessed natural death occurring within one hour of the onset of symptoms...

Detecting early cardiac dysfunction with radionuclide cardiac blood-pool imaging

International Nuclear Information System (INIS)

Wu Kegui; Chen Daguang; Lin Haoxue

1992-01-01

Cardiac function was measured by radionuclide cardiac blood-pool imaging in 15 normal persons, 19 cases of hypertension, 32 cases of coronary heart disease, 35 cases of coronary heart disease combined with hypertension and 44 cases of myocardial infarction. Significant differences have been found in indices of cardiac function between normal subjects and patients with coronary heart disease and coronary heart disease combined with hypertension, even though the patients were without any clinical sin of cardiac failure. Lowered regional EF and decreased ventricular was motion were found in 38.8% of patients, while 65.7%of patients revealed marked abnormality in MFR. The results indicate that latent cardiac dysfunction is common in patients with coronary heart disease. The earliest change is diastolic function abnormalities

Cardiac Function Remains Impaired Despite Reversible Cardiac Remodeling after Acute Experimental Viral Myocarditis

Directory of Open Access Journals (Sweden)

Peter Moritz Becher

2017-01-01

Full Text Available Background. Infection with Coxsackievirus B3 induces myocarditis. We aimed to compare the acute and chronic phases of viral myocarditis to identify the immediate effects of cardiac inflammation as well as the long-term effects after resolved inflammation on cardiac fibrosis and consequently on cardiac function. Material and Methods. We infected C57BL/6J mice with Coxsackievirus B3 and determined the hemodynamic function 7 as well as 28 days after infection. Subsequently, we analyzed viral burden and viral replication in the cardiac tissue as well as the expression of cytokines and matrix proteins. Furthermore, cardiac fibroblasts were infected with virus to investigate if viral infection alone induces profibrotic signaling. Results. Severe cardiac inflammation was determined and cardiac fibrosis was consistently colocalized with inflammation during the acute phase of myocarditis. Declined cardiac inflammation but no significantly improved hemodynamic function was observed 28 days after infection. Interestingly, cardiac fibrosis declined to basal levels as well. Both cardiac inflammation and fibrosis were reversible, whereas the hemodynamic function remains impaired after healed viral myocarditis in C57BL/6J mice.

Current role of cardiac and extra-cardiac pathologies in clinically indicated cardiac computed tomography with emphasis on status before pulmonary vein isolation

Energy Technology Data Exchange (ETDEWEB)

Sohns, J.M.; Lotz, J. [Goettingen University Medical Center (Germany). Inst. for Diagnostic and Interventional Radiology; German Center for Cardiovascular Research (DZHK), Goettingen (Germany); Menke, J.; Staab, W.; Fasshauer, M.; Kowallick, J.T.; Zwaka, P.A.; Schwarz, A. [Goettingen University Medical Center (Germany). Inst. for Diagnostic and Interventional Radiology; Spiro, J. [Koeln University Hospital (Germany). Radiology; Bergau, L.; Unterberg-Buchwald, C. [Goettingen University Medical Center (Germany). Cardiology and Pneumology

2014-09-15

Purpose: The aim of this study was to assess the incidence of cardiac and significant extra-cardiac findings in clinical computed tomography of the heart in patients with atrial fibrillation before pulmonary vein isolation (PVI). Materials and Methods: 224 patients (64 ± 10 years; male 63%) with atrial fibrillation were examined by cardiac 64-slice multidetector CT before PVI. Extra-cardiac findings were classified as 'significant' if they were recommended to additional diagnostics or therapy, and otherwise as 'non-significant'. Additionally, cardiac findings were documented in detail. Results: A total of 724 cardiac findings were identified in 203 patients (91% of patients). Additionally, a total of 619 extra-cardiac findings were identified in 179 patients (80% of patients). Among these extra-cardiac findings 196 (32%) were 'significant', and 423 (68%) were 'non-significant'. In 2 patients (1%) a previously unknown malignancy was detected (esophageal cancer and lung cancer, local stage, no metastasis). 203 additional imaging diagnostics followed to clarify the 'significant' findings (124 additional CT, costs 38,314.69 US dollars). Overall, there were 3.2 cardiac and 2.8 extra-cardiac findings per patient. Extra-cardiac findings appear significantly more frequently in patients over 60 years old, in smokers and in patients with a history of cardiac findings (p < 0.05). Conclusion: Cardiac CT scans before PVI should be screened for extracardiac incidental findings that could have important clinical implications for each patient. (orig.)

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

PHYSIOLOGICAL MONITORING OPERATORS ACS IN AUDIO-VISUAL SIMULATION OF AN EMERGENCY

Directory of Open Access Journals (Sweden)

S. S. Aleksanin

2010-01-01

Full Text Available In terms of ship simulator automated control systems we have investigated the information content of physiological monitoring cardiac rhythm to assess the reliability and noise immunity of operators of various specializations with audio-visual simulation of an emergency. In parallel, studied the effectiveness of protection against the adverse effects of electromagnetic fields. Monitoring of cardiac rhythm in a virtual crash it is possible to differentiate the degree of voltage regulation systems of body functions of operators on specialization and note the positive effect of the use of means of protection from exposure of electromagnetic fields.

Cardiac and Metabolic Effects of Dietary Selenomethionine Exposure in Adult Zebrafish.

Science.gov (United States)

Pettem, Connor M; Weber, Lynn P; Janz, David M

2017-10-01

Selenium (Se) is an essential micronutrient involved in important metabolic functions for all vertebrate species. As Se is reported to have a narrow margin between essentiality and toxicity, there is growing concern surrounding the adverse effects of elevated Se exposure caused by anthropogenic activities. Recent studies have reported that elevated dietary exposure of fish to selenomethionine (Se-Met) can alter aerobic metabolic capacity, energetics and swimming performance. This study aims to further investigate mechanisms of sublethal Se-Met toxicity, particularly potential underlying cardiovascular implications of chronic exposure to environmentally relevant concentrations of dietary Se-Met in adult zebrafish (Danio rerio). Adult zebrafish were fed either control food (1.1 μg Se/g dry mass [d.m.]) or Se-Met spiked food (10.3 or 28.8 μg Se/g d.m.) for 90 d at 5% body weight per day. Following exposure, ultrahigh resolution B-mode and Doppler ultrasound was used to characterize cardiac function. Chronic dietary exposure to elevated Se-Met significantly reduced ventricular contractile rate, stroke volume, and cardiac output. Exposure to Se-Met significantly decreased mRNA expression of methionine adenosyltransferase 1 alpha and glutathione-S-transferase pi class in liver, and a key cardiac remodelling enzyme, matrix metalloproteinase 2, in adult zebrafish heart. Se-Met significantly increased echodensity at the junction between atrium and ventricle, and these results combined with increased matrix metalloproteinase 2 expression are consistent with cardiac remodelling and fibrosis. The results of this study suggest that chronic exposure to dietary Se-Met can negatively impact cardiac function, and such physiological consequences could reduce the aerobic capacity and survivability of fish. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Epidemiology and Outcomes After In-Hospital Cardiac Arrest After Pediatric Cardiac Surgery

Science.gov (United States)

Gupta, Punkaj; Jacobs, Jeffrey P.; Pasquali, Sara K.; Hill, Kevin D.; Gaynor, J. William; O’Brien, Sean M.; He, Max; Sheng, Shubin; Schexnayder, Stephen M.; Berg, Robert A.; Nadkarni, Vinay M.; Imamura, Michiaki; Jacobs, Marshall L.

2014-01-01

Background Multicenter data regarding cardiac arrest in children undergoing heart operations are limited. We describe epidemiology and outcomes associated with postoperative cardiac arrest in a large multiinstitutional cohort. Methods Patients younger than 18 years in the Society of Thoracic Surgeons Congenital Heart Surgery Database (2007 through 2012) were included. Patient factors, operative characteristics, and outcomes were described for patients with and without postoperative cardiac arrest. Multivariable models were used to evaluate the association of center volume with cardiac arrest rate and mortality after cardiac arrest, adjusting for patient and procedural factors. Results Of 70,270 patients (97 centers), 1,843 (2.6%) had postoperative cardiac arrest. Younger age, lower weight, and presence of preoperative morbidities (all p < 0.0001) were associated with cardiac arrest. Arrest rate increased with procedural complexity across common benchmark operations, ranging from 0.7% (ventricular septal defect repair) to 12.7% (Norwood operation). Cardiac arrest was associated with significant mortality risk across procedures, ranging from 15.4% to 62.3% (all p < 0.0001). In multivariable analysis, arrest rate was not associated with center volume (odds ratio, 1.06; 95% confidence interval, 0.71 to 1.57 in low- versus high-volume centers). However, mortality after cardiac arrest was higher in low-volume centers (odds ratio, 2.00; 95% confidence interval, 1.52 to 2.63). This association was present for both high- and low-complexity operations. Conclusions Cardiac arrest carries a significant mortality risk across the stratum of procedural complexity. Although arrest rates are not associated with center volume, lower-volume centers have increased mortality after cardiac arrest. Further study of mechanisms to prevent cardiac arrest and to reduce mortality in those with an arrest is warranted. PMID:25443018

From Static Output Feedback to Structured Robust Static Output Feedback: A Survey

OpenAIRE

Sadabadi , Mahdieh ,; Peaucelle , Dimitri

2016-01-01

This paper reviews the vast literature on static output feedback design for linear time-invariant systems including classical results and recent developments. In particular, we focus on static output feedback synthesis with performance specifications, structured static output feedback, and robustness. The paper provides a comprehensive review on existing design approaches including iterative linear matrix inequalities heuristics, linear matrix inequalities with rank constraints, methods with ...

Novel axolotl cardiac function analysis method using magnetic resonance imaging.

Directory of Open Access Journals (Sweden)

Pedro Gomes Sanches

Full Text Available The salamander axolotl is capable of complete regeneration of amputated heart tissue. However, non-invasive imaging tools for assessing its cardiac function were so far not employed. In this study, cardiac magnetic resonance imaging is introduced as a non-invasive technique to image heart function of axolotls. Three axolotls were imaged with magnetic resonance imaging using a retrospectively gated Fast Low Angle Shot cine sequence. Within one scanning session the axolotl heart was imaged three times in all planes, consecutively. Heart rate, ejection fraction, stroke volume and cardiac output were calculated using three techniques: (1 combined long-axis, (2 short-axis series, and (3 ultrasound (control for heart rate only. All values are presented as mean ± standard deviation. Heart rate (beats per minute among different animals was 32.2±6.0 (long axis, 30.4±5.5 (short axis and 32.7±4.9 (ultrasound and statistically similar regardless of the imaging method (p > 0.05. Ejection fraction (% was 59.6±10.8 (long axis and 48.1±11.3 (short axis and it differed significantly (p = 0.019. Stroke volume (μl/beat was 133.7±33.7 (long axis and 93.2±31.2 (short axis, also differed significantly (p = 0.015. Calculations were consistent among the animals and over three repeated measurements. The heart rate varied depending on depth of anaesthesia. We described a new method for defining and imaging the anatomical planes of the axolotl heart and propose one of our techniques (long axis analysis may prove useful in defining cardiac function in regenerating axolotl hearts.

Regimes of data output from an automated scanning system into a computer

International Nuclear Information System (INIS)

Ovsov, Yu.V.; Shaislamov, P.T.

1984-01-01

A method is described for accomplishment of rather a complex algorithm of various coordinate and service data transmission from different automated scanning system devices into a monitoring computer in the automated system for processing images from bubble chambers. The accepted data output algorithm and the developed appropriate equipment enable data transmission both in separate words and word arrays

Diabetes Mellitus, Microalbuminuria, and Subclinical Cardiac Disease: Identification and Monitoring of Individuals at Risk of Heart Failure.

Science.gov (United States)

Swoboda, Peter P; McDiarmid, Adam K; Erhayiem, Bara; Ripley, David P; Dobson, Laura E; Garg, Pankaj; Musa, Tarique A; Witte, Klaus K; Kearney, Mark T; Barth, Julian H; Ajjan, Ramzi; Greenwood, John P; Plein, Sven

2017-07-17

Patients with type 2 diabetes mellitus and elevated urinary albumin:creatinine ratio (ACR) have increased risk of heart failure. We hypothesized this was because of cardiac tissue changes rather than silent coronary artery disease. In a case-controlled observational study 130 subjects including 50 ACR+ve diabetes mellitus patients with persistent microalbuminuria (ACR >2.5 mg/mol in males and >3.5 mg/mol in females, ≥2 measurements, no previous renin-angiotensin-aldosterone therapy, 50 ACR-ve diabetes mellitus patients and 30 controls underwent cardiovascular magnetic resonance for investigation of myocardial fibrosis, ischemia and infarction, and echocardiography. Thirty ACR+ve patients underwent further testing after 1-year treatment with renin-angiotensin-aldosterone blockade. Cardiac extracellular volume fraction, a measure of diffuse fibrosis, was higher in diabetes mellitus patients than controls (26.1±3.4% and 23.3±3.0% P =0.0002) and in ACR+ve than ACR-ve diabetes mellitus patients (27.2±4.1% versus 25.1±2.9%, P =0.004). ACR+ve patients also had lower E' measured by echocardiography (8.2±1.9 cm/s versus 8.9±1.9 cm/s, P =0.04) and elevated high-sensitivity cardiac troponin T 18% versus 4% ≥14 ng/L ( P =0.05). Rate of silent myocardial ischemia or infarction were not influenced by ACR status. Renin-angiotensin-aldosterone blockade was associated with increased left ventricular ejection fraction (59.3±7.8 to 61.5±8.7%, P =0.03) and decreased extracellular volume fraction (26.5±3.6 to 25.2±3.1, P =0.01) but no changes in diastolic function or high-sensitivity cardiac troponin T levels. Asymptomatic diabetes mellitus patients with persistent microalbuminuria have markers of diffuse cardiac fibrosis including elevated extracellular volume fraction, high-sensitivity cardiac troponin T, and diastolic dysfunction, which may in part be reversible by renin-angiotensin-aldosterone blockade. Increased risk in these patients may be mediated by

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.

[Therapy of low-output syndrome in patients following cardiopulmonary bypass with sodium nitroprusside and dopamine].

Science.gov (United States)

van Ackern, K; Franke, N; Peter, K

1978-01-01

In 12 patients with low output after open-heart surgery the therapeutic effect of vasodilatation with sodium nitroprusside (SNP) and dopamine was studied. All patients underwent aortocoronary bypass operations. After cardiopulmonary bypass, the cardiac index (CI) was 2.2 liters/min.m2. The pulmonary wedge pressure (PCWP) was about 20 mm Hg. Application of SNP lowered mean arterial pressure to 82 and PCWP to 13 mm Hg. Then PCWP was elevated to the control level by tranfusion of blood. This therapy increased CI by about 30% without positive inotropic intervention. Additional application of 5 micrograms dopamine/kg.min improved the CI to 3.8 liters/min.m2.

Cardiac output by Doppler echocardiography in the premature baboon: Comparison with radiolabeled microspheres

International Nuclear Information System (INIS)

Kinsella, J.P.; Morrow, W.R.; Gerstmann, D.R.; Taylor, A.F.; deLemos, R.A.

1991-01-01

Pulsed-Doppler echocardiography (PDE) is a useful noninvasive method for determining left ventricular output (LVO). However, despite increasingly widespread use in neonatal intensive care units, validation studies in prematures with cardiopulmonary disease are lacking. The purpose of this study was to compare radiolabeled microsphere (RLM) and PDE measurements of LVO, using the critically ill premature baboon as a model of the human neonate. Twenty-two paired RLM and PDE measurements of LVO were obtained in 14 animals between 3 and 24 h of age. Average PDE LVO was 152 ml/min/kg (range, 40-258 ml/min/kg) compared to 158 ml/min/kg (range, 67-278 ml/min/kg) measured by RLM. Linear regression analysis of the paired measurements showed good correlation with a slope near unity (gamma = 0.94x + 4.20, r = 0.91, SEE = 25.7 ml). The authors conclude that PDE determinations of LVO compare well with those measured by RLM in the premature baboon. PDE appears to provide a valid estimate of LVO and should be useful in human prematures with cardiopulmonary distress

Cardiopulmonary bypass in pregnancy.

Science.gov (United States)

Kapoor, Mukul Chandra

2014-01-01

Cardiac surgery carried out on cardiopulmonary bypass (CPB) in a pregnant woman is associated with poor neonatal outcomes although maternal outcomes are similar to cardiac surgery in non-pregnant women. Most adverse maternal and fetal outcomes from cardiac surgery during pregnancy are attributed to effects of CPB. The CPB is associated with utero-placental hypoperfusion due to a number of factors, which may translate into low fetal cardiac output, hypoxia and even death. Better maternal and fetal outcomes may be achieved by early pre-operative optimization of maternal cardiovascular status, use of perioperative fetal monitoring, optimization of CPB, delivery of a viable fetus before the operation and scheduling cardiac surgery on an elective basis during the second trimester.