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Sample records for beating heart intracardiac

  1. Non heart-beating donors in England

    Directory of Open Access Journals (Sweden)

    Eleazar Chaib

    2008-01-01

    Full Text Available When transplantation started all organs were retrieved from patients immediately after cardio-respiratory arrest, i.e. from nonheart-beating donors. After the recognition that death resulted from irreversible damage to the brainstem, organ retrieval rapidly switched to patients certified dead after brainstem testing. These heart-beating-donors have become the principal source of organs for transplantation for the last 30 years. The number of heart-beating-donors are declining and this is likely to continue, therefore cadaveric organs from non-heart-beating donor offers a large potential of resources for organ transplantation. The aim of this study is to examine clinical outcomes of non-heart-beating donors in the past 10 years in the UK as an way of decreasing pressure in the huge waiting list for organs transplantation.

  2. Intracardiac Echocardiography for Structural Heart and Electrophysiological Interventions.

    Science.gov (United States)

    Basman, Craig; Parmar, Yuvrajsinh J; Kronzon, Itzhak

    2017-09-06

    With an increasing number of interventional procedures performed for structural heart disease and cardiac arrhythmias each year, echocardiographic guidance is necessary for safe and efficient results. The purpose of this review article is to overview the principles of intracardiac echocardiography (ICE) and describes the peri-interventional role of ICE in a variety of structural heart disease and electrophysiological interventions. Both transthoracic (TTE) and transesophageal echocardiography have limitations. ICE provides the advantage of imaging from within the heart, providing shorter image distances and higher resolution. ICE may be performed without sedation and avoids esophageal intubation as with transesophageal echocardiography (TEE). Limitations of ICE include the need for additional venous access with possibility of vascular complications, potentially higher costs, and a learning curve for new operators. Data supports the use of ICE in guiding device closure of interatrial shunts, transseptal puncture, and electrophysiologic procedures. This paper reviews the more recent reports that ICE may be used for primary guidance or as a supplement to TEE in patients undergoing left atrial appendage (LAA) closure, interatrial shunt closure, transaortic valve implantation (TAVI), percutaneous mitral valve repair (PMVR), paravalvular leak (PVL) closure, aortic interventions, transcatheter pulmonary valve replacement (tPVR), ventricular septal defect (VSD), and patent ductus arteriosus (PDA) closure. ICE imaging technology will continue to expand and help improve structural heart and electrophysiology interventions.

  3. Towards robot-assisted anchor deployment in beating-heart mitral valve surgery.

    Science.gov (United States)

    Cheng, Lingbo; Sharifi, Mojtaba; Tavakoli, Mahdi

    2018-03-24

    Beating-heart intracardiac surgery promises significant benefits for patients compared with cardiopulmonary bypass based procedures. However, the fast motions of the heart introduce serious challenges for surgeons. In this work, a new impedance-controlled master-slave telerobotic system is developed to help perform anchor deployment for mitral valve annuloplasty under the guidance of live ultrasound images of the heart. The proposed bilateral teleoperation system can both reflect the non-oscillatory portion of slave-heart tissue interaction force on the surgeon's hand as haptic feedback and implement rapid compensation for the beating heart's motion. The surgical task involves performing anchor deployment on a simulated moving heart tissue to evaluate the effectiveness of the proposed strategy for safely interacting with a moving organ. The results obtained show that the telerobotic system increases the success rate of anchor deployment by 100% and reduces the excess force application rate by 70% compared with manual attempts. Copyright © 2018 John Wiley & Sons, Ltd.

  4. 4D ultrasound and 3D MRI registration of beating heart

    International Nuclear Information System (INIS)

    Herlambang, N.; Matsumiya, K.; Masamune, K.; Dohi, T.; Liao, H.; Tsukihara, H.; Takamoto, S.

    2007-01-01

    To realize intra-cardiac surgery without cardio-pulmonary bypass, a medical imaging technique with both high image quality and data acquisition rate that is fast enough to follow heart beat movements is required. In this research, we proposed a method that utilized the image quality of MRI and the speed of ultrasound. We developed a 4D image reconstruction method using image registration of 3D MRI and 4D ultrasound images. The registration method consists of rigid registration between 3D MRI and 3D ultrasound with the same heart beat phase, and non-rigid registration between 3D ultrasound images from different heart beat phases. Non-rigid registration was performed with B-spline based registration using variable spring model. In phantom experiment using balloon phantom, registration accuracy was less than 2 mm for total heart volume variation range of 10%. We applied our registration method on 3D MRI and 4D ultrasound images of a volunteer's beating heart data and confirmed through visual observation that heart beat pattern was well reproduced. (orig.)

  5. Force Tracking with Feed-Forward Motion Estimation for Beating Heart Surgery.

    Science.gov (United States)

    Yuen, Shelten G; Perrin, Douglas P; Vasilyev, Nikolay V; Del Nido, Pedro J; Howe, Robert D

    2010-08-16

    The manipulation of fast moving, delicate tissues in beating heart procedures presents a considerable challenge to the surgeon. A robotic force tracking system can assist the surgeon by applying precise contact forces to the beating heart during surgical manipulation. Standard force control approaches cannot safely attain the required bandwidth for this application due to vibratory modes within the robot structure. These vibrations are a limitation even for single degree of freedom systems driving long surgical instruments. These bandwidth limitations can be overcome by incorporating feed-forward motion terms in the control law. For intracardiac procedures, the required motion estimates can be derived from 3D ultrasound imaging. Dynamic analysis shows that a force controller with feed-forward motion terms can provide safe and accurate force tracking for contact with structures within the beating heart. In vivo validation confirms that this approach confers a 50% reduction in force fluctuations when compared to a standard force controller and a 75% reduction in fluctuations when compared to manual attempts to maintain the same force.

  6. Intracardiac Origin of Heart Rate Variability, Pacemaker Funny Current and their Possible Association with Critical Illness

    Science.gov (United States)

    Papaioannou, Vasilios E; Verkerk, Arie O; Amin, Ahmed S; de Bakker, Jaques MT

    2013-01-01

    Heart rate variability (HRV) is an indirect estimator of autonomic modulation of heart rate and is considered a risk marker in critical illness, particularly in heart failure and severe sepsis. A reduced HRV has been found in critically ill patients and has been associated with neuro-autonomic uncoupling or decreased baroreflex sensitivity. However, results from human and animal experimental studies indicate that intracardiac mechanisms might also be responsible for interbeat fluctuations. These studies have demonstrated that different membrane channel proteins and especially the so-called ‘funny’ current (If), an hyperpolarization-activated, inward current that drives diastolic depolarization resulting in spontaneous activity in cardiac pacemaker cells, are altered during critical illness. Furthermore, membrane channels kinetics seem to have significant impact upon HRV, whose early decrease might reflect a cellular metabolic stress. In this review article we present research findings regarding intracardiac origin of HRV, at the cellular level and in both isolated sinoatrial node and whole ex vivo heart preparations. In addition, we will review results from various experimental studies that support the interrelation between If and HRV during endotoxemia. We suggest that reduced HRV during sepsis could also be associated with altered pacemaker cell membrane properties, due to ionic current remodeling. PMID:22920474

  7. External Counterpulsation Increases Beat-to-Beat Heart Rate Variability in Patients with Ischemic Stroke.

    Science.gov (United States)

    Xiong, Li; Tian, Ge; Wang, Li; Lin, Wenhua; Chen, Xiangyan; Leung, Thomas Wai Hong; Soo, Yannie Oi Yan; Wong, Lawrence Ka Sing

    2017-07-01

    External counterpulsation (ECP) is a noninvasive method used to augment cerebral perfusion in ischemic stroke. However, the response of beat-to-beat heart rate variability (HRV) in patients with ischemic stroke during ECP remains unknown. Forty-eight patients with unilateral ischemic stroke at the subacute stage and 14 healthy controls were recruited. Beat-to-beat heart rate before, during, and after ECP was monitored. The frequency components of HRV were calculated using power spectral analysis. Very low frequency (VLF; <.04 Hz), low frequency (LF; .04-.15 Hz), high frequency (HF; .15-.40 Hz), total power spectral density (TP; <.40 Hz), and LF/HF ratio were calculated. In stroke patients, although there were no statistical differences in all of the HRV components, the HRV at VLF showed a trend of increase during ECP compared with baseline in the left-sided stroke patients (P = .083). After ECP, the HRV at LF and TP remained higher than baseline in the right-sided stroke patients (LF, 209.4 versus 117.9, P = .050; TP, 1275.6 versus 390.2, P = .017, respectively). Besides, the HRV at TP also increased after ECP compared with baseline in the left-sided stroke patients (563.0 versus 298.3, P = .029). Irrespective of the side of the ischemia, patients showed an increased beat-to-beat HRV after ECP. Additionally, sympathetic and parasympathetic cardiac modulations were increased after ECP in patients after right-sided subacute stroke. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  8. Non-heart beating organ donation : overview and future perspectives

    NARCIS (Netherlands)

    Moers, Cyril; Leuvenink, Henri G. D.; Ploeg, Rutger J.

    New indications for organ transplantation combined with a stagnating number of available donor grafts have severely lengthened the waiting list for almost all types of transplantations. This has led to a renewed interest in non-heart beating (NHB) donation, as a possible solution to bridge the gap

  9. Heart beat detection using a multimodal data coupling method.

    Science.gov (United States)

    Mollakazemi, M Javad; Atyabi, S Abbas; Ghaffari, Ali

    2015-08-01

    The most straightforward method for heart beat estimation is R-peak detection based on an electrocardiogram (ECG) signal. Current R-peak detection methods do not work properly when the ECG signal is contaminated or missing, which leads to the incorrect estimation of the heart rate. This raises the need for reliable algorithms which can locate heart beats in continuous long-term multimodal data, allowing robust analysis.In this paper, three peak detectors are evaluated for heart beat detection using various cardiovascular signals. One of the peak detectors is a new general peak detector (GPD) algorithm which is applicable on ECG and other pulsatile signals to compensate for the limitation of QRS detection. This peak detector algorithm is adaptive and independently finds amplitude characteristics for every recording, while not tuned for ECG or other pulsatile signals. Three strategies, which are different disciplines of detectors, are then proposed while the fusion method remains the same in all strategies. In the first strategy, the ECG and the lowest-indexed signal of general blood pressure (BP), arterial blood pressure (ART) and pulmonary arterial pressure (PAP) are processed through gqrs and wabp (from the PhysioNet library), respectively. In the second strategy, all beats in different signals are detected by GPD. In the third strategy, ECG and other signals are processed by gqrs and GPD, respectively. In all three strategies two criteria are used in order to fuse the detections. The first criterion is based on the number of candidate detections in a specific time period, based on which signals of interest are selected. The second fusion criterion is based on the regularity of the derived intervals between subsequent candidate detections. If the number of detections in ECG and one of BP, ART and PAP signals have reasonable physiological range, a new signal is generated in which they are coupled with each other. Heart beats can more easily be detected in noisy

  10. Connection forms for beating the heart

    DEFF Research Database (Denmark)

    Mensch, Arthur; Piuze, Emmanuel; Lehnert, Lucas

    2014-01-01

    We combine recent work on modeling cardiac mechanics using a finite volume method with the insight that heart wall myofiber orientations exhibit a particular volumetric geometry. In our finite vol- ume mechanical simulation we use Maurer-Cartan one-forms to add a geometrical consistency term...... to control the rate at which myofiber ori- entation changes in the direction perpendicular to the heart wall. This allows us to estimate material properties related to both the passive and active parameters in our model. We have obtained preliminary results on the 4 canine datasets of the 2014 mechanics...... challenge using the FEBio software suite. In ongoing work we are validating and improving the model using rat heart (ex-vivo DTI and in-vivo tagging) MRI datasets, from which we have estimated strain tensors....

  11. Editorial: Robust Detection of Heart Beats in Multimodal Data

    Science.gov (United States)

    Silva, Ikaro; Moody, Benjamin; Behar, Joachim; Johnson, Alistair; Oster, Julien; Clifford, Gari D.; Moody, George B.

    2015-01-01

    This editorial reviews the background issues, the design, the key achievements, and the follow-up research generated as a result of the PhysioNet/Computing in Cardiology (CinC) 2014 Challenge, published in the concurrent special issue of Physiological Measurement. Our major focus was to accelerate the development and facilitate the comparison of robust methods for locating heart beats in long-term multi-channel recordings. A public (training) database consisting of 151,032 annotated beats was compiled from records that contained ECGs as well as pulsatile signals that directly reflect cardiac activity, and other signals that may have few or no observable markers of heart beats. A separate hidden test data set (consisting of 152,478 beats) is permanently stored at PhysioNet, and a public framework has been developed to provide researchers the ability to continue to automatically score and compare the performance of their algorithms. A scoring criteria based on the averaging of gross sensitivity, gross positive predictivity, average sensitivity, and average positive predictivity is proposed. The top three scores (as of March 2015) on the hidden test data set were 93.64%, 91.50%, and 90.70%. PMID:26217894

  12. Robust detection of heart beats in multimodal data.

    Science.gov (United States)

    Silva, Ikaro; Moody, Benjamin; Behar, Joachim; Johnson, Alistair; Oster, Julien; Clifford, Gari D; Moody, George B

    2015-08-01

    This editorial reviews the background issues, the design, the key achievements, and the follow-up research generated as a result of the PhysioNet/Computing in Cardiology (CinC) Challenge 2014, published in the concurrent focus issue of Physiological Measurement. Our major focus was to accelerate the development and facilitate the comparison of robust methods for locating heart beats in long-term multi-channel recordings. A public (training) database consisting of 151 032 annotated beats was compiled from records that contained ECGs as well as pulsatile signals that directly reflect cardiac activity, and other signals that may have few or no observable markers of heart beats. A separate hidden test data set (consisting of 152 478 beats) is permanently stored at PhysioNet, and a public framework has been developed to provide researchers with the ability to continue to automatically score and compare the performance of their algorithms. A scoring criteria based on the averaging of gross sensitivity, gross positive predictivity, average sensitivity, and average positive predictivity is proposed. The top three scores (as of March 2015) on the hidden test data set were 93.64%, 91.50%, and 90.70%.

  13. Beating-heart surgical treatment of tricuspid valve papillary fibroelastoma

    OpenAIRE

    Li, Weidong; Zheng, Junnan; Zhao, Hengchi; Xu, Hongfei; Ni, Yiming

    2016-01-01

    Abstract Background: Cardiac papillary fibroelastomas are rare. And only 15% of the papillary fibroelastomas are located on tricuspid valve. However, the treatment of papillary fibroelastomas varies. Case summary: We report a 75-year-old Chinese male who was hospitalized because of a right atrial mass found by echocardiography. Complete tumor excision along with Kay's tricuspid valvuloplasty surgery on beating heart under cardiopulmonary bypass was performed to the patient. Pathologic examina...

  14. Make the call, don't miss a beat: Heart Attack Information for Women

    Science.gov (United States)

    ... Other resources Learn more about heart disease and heart attacks. Make the Call, Don't Miss a Beat ... symptoms Learn the 7 most common signs of heart attack in men and women. Chest pain or discomfort " ...

  15. Ultrasound Current Source Density Imaging in live rabbit hearts using clinical intracardiac catheter

    Science.gov (United States)

    Li, Qian

    between the recording electrode distance and the measured AE signal amplitude in gel phantoms and excised porcine heart tissue using a clinical intracardiac catheter. Sensitivity of UCSDI with catheter was 4.7 microV/mA (R2 = 0.999) in cylindrical gel (0.9% NaCl), and 3.2 microV/mA (R2 = 0.92) in porcine heart tissue. The AE signal was detectable more than 25 mm away from the source in cylindrical gel (0.9% NaCl). Effect of transducer properties on UCSDI sensitivity is also investigated using simulation. The optimal ultrasound transducer parameters chosen for cardiac imaging are center frequency = 0.5 MHz and f/number = 1.4. Last but not least, this dissertation shows the result of implementing the optimized ultrasound parameters in live rabbit heart preparation, the comparison of different recording electrode configuration and multichannel UCSDI recording and reconstruction. The AE signal detected using the 0.5 MHz transducer was much stronger (2.99 microV/MPa) than the 1.0 MHz transducer (0.42 microV/MPa). The clinical lasso catheter placed on the epicardium exhibited excellent sensitivity without being too invasive. 3-dimensional cardiac activation maps of the live rabbit heart using only one pair of recording electrodes were also demonstrated for the first time. Cardiac conduction velocity for atrial (1.31 m/s) and apical (0.67 m/s) pacing were calculated based on the activation maps. The future outlook of this dissertation includes integrating UCSDI with 2-dimensional ultrasound transducer array for fast imaging, and developing a multi-modality catheter with 4-dimensional UCSDI, multi-electrode recording and echocardiography capacity.

  16. Beat-to-beat systolic time-interval measurement from heart sounds and ECG

    International Nuclear Information System (INIS)

    Paiva, R P; Carvalho, P; Couceiro, R; Henriques, J; Antunes, M; Quintal, I; Muehlsteff, J

    2012-01-01

    Systolic time intervals are highly correlated to fundamental cardiac functions. Several studies have shown that these measurements have significant diagnostic and prognostic value in heart failure condition and are adequate for long-term patient follow-up and disease management. In this paper, we investigate the feasibility of using heart sound (HS) to accurately measure the opening and closing moments of the aortic heart valve. These moments are crucial to define the main systolic timings of the heart cycle, i.e. pre-ejection period (PEP) and left ventricular ejection time (LVET). We introduce an algorithm for automatic extraction of PEP and LVET using HS and electrocardiogram. PEP is estimated with a Bayesian approach using the signal's instantaneous amplitude and patient-specific time intervals between atrio-ventricular valve closure and aortic valve opening. As for LVET, since the aortic valve closure corresponds to the start of the S2 HS component, we base LVET estimation on the detection of the S2 onset. A comparative assessment of the main systolic time intervals is performed using synchronous signal acquisitions of the current gold standard in cardiac time-interval measurement, i.e. echocardiography, and HS. The algorithms were evaluated on a healthy population, as well as on a group of subjects with different cardiovascular diseases (CVD). In the healthy group, from a set of 942 heartbeats, the proposed algorithm achieved 7.66 ± 5.92 ms absolute PEP estimation error. For LVET, the absolute estimation error was 11.39 ± 8.98 ms. For the CVD population, 404 beats were used, leading to 11.86 ± 8.30 and 17.51 ± 17.21 ms absolute PEP and LVET errors, respectively. The results achieved in this study suggest that HS can be used to accurately estimate LVET and PEP. (paper)

  17. Beat-to-beat systolic time-interval measurement from heart sounds and ECG.

    Science.gov (United States)

    Paiva, R P; Carvalho, P; Couceiro, R; Henriques, J; Antunes, M; Quintal, I; Muehlsteff, J

    2012-02-01

    Systolic time intervals are highly correlated to fundamental cardiac functions. Several studies have shown that these measurements have significant diagnostic and prognostic value in heart failure condition and are adequate for long-term patient follow-up and disease management. In this paper, we investigate the feasibility of using heart sound (HS) to accurately measure the opening and closing moments of the aortic heart valve. These moments are crucial to define the main systolic timings of the heart cycle, i.e. pre-ejection period (PEP) and left ventricular ejection time (LVET). We introduce an algorithm for automatic extraction of PEP and LVET using HS and electrocardiogram. PEP is estimated with a Bayesian approach using the signal's instantaneous amplitude and patient-specific time intervals between atrio-ventricular valve closure and aortic valve opening. As for LVET, since the aortic valve closure corresponds to the start of the S2 HS component, we base LVET estimation on the detection of the S2 onset. A comparative assessment of the main systolic time intervals is performed using synchronous signal acquisitions of the current gold standard in cardiac time-interval measurement, i.e. echocardiography, and HS. The algorithms were evaluated on a healthy population, as well as on a group of subjects with different cardiovascular diseases (CVD). In the healthy group, from a set of 942 heartbeats, the proposed algorithm achieved 7.66 ± 5.92 ms absolute PEP estimation error. For LVET, the absolute estimation error was 11.39 ± 8.98 ms. For the CVD population, 404 beats were used, leading to 11.86 ± 8.30 and 17.51 ± 17.21 ms absolute PEP and LVET errors, respectively. The results achieved in this study suggest that HS can be used to accurately estimate LVET and PEP.

  18. Beating-heart registration for organ-mounted robots.

    Science.gov (United States)

    Wood, Nathan A; Schwartzman, David; Passineau, Michael J; Moraca, Robert J; Zenati, Marco A; Riviere, Cameron N

    2018-03-06

    Organ-mounted robots address the problem of beating-heart surgery by adhering to the heart, passively providing a platform that approaches zero relative motion. Because of the quasi-periodic deformation of the heart due to heartbeat and respiration, registration must address not only spatial registration but also temporal registration. Motion data were collected in the porcine model in vivo (N = 6). Fourier series models of heart motion were developed. By comparing registrations generated using an iterative closest-point approach at different phases of respiration, the phase corresponding to minimum registration distance is identified. The spatiotemporal registration technique presented here reduces registration error by an average of 4.2 mm over the 6 trials, in comparison with a more simplistic static registration that merely averages out the physiological motion. An empirical metric for spatiotemporal registration of organ-mounted robots is defined and demonstrated using data from animal models in vivo. Copyright © 2018 John Wiley & Sons, Ltd.

  19. Peak misdetection in heart-beat-based security : Characterization and tolerance

    NARCIS (Netherlands)

    Seepers, Robert M; Strydis, Christos; Peris-Lopez, Pedro; Sourdis, Ioannis; De Zeeuw, Chris I

    The Inter-Pulse-Interval (IPI) of heart beats has previously been suggested for security in mobile health (mHealth) applications. In IPI-based security, secure communication is facilitated through a security key derived from the time difference between heart beats. However, there currently exists no

  20. Mast Cell Coupling to the Kallikrein–Kinin System Fuels Intracardiac Parasitism and Worsens Heart Pathology in Experimental Chagas Disease

    Directory of Open Access Journals (Sweden)

    Clarissa R. Nascimento

    2017-08-01

    Full Text Available During the course of Chagas disease, infectious forms of Trypanosoma cruzi are occasionally liberated from parasitized heart cells. Studies performed with tissue culture trypomastigotes (TCTs, Dm28c strain demonstrated that these parasites evoke neutrophil/CXCR2-dependent microvascular leakage by activating innate sentinel cells via toll-like receptor 2 (TLR2. Upon plasma extravasation, proteolytically derived kinins and C5a stimulate immunoprotective Th1 responses via cross-talk between bradykinin B2 receptors (B2Rs and C5aR. Awareness that TCTs invade cardiovascular cells in vitro via interdependent activation of B2R and endothelin receptors [endothelin A receptor (ETAR/endothelin B receptor (ETBR] led us to hypothesize that T. cruzi might reciprocally benefit from the formation of infection-associated edema via activation of kallikrein–kinin system (KKS. Using intravital microscopy, here we first examined the functional interplay between mast cells (MCs and the KKS by topically exposing the hamster cheek pouch (HCP tissues to dextran sulfate (DXS, a potent “contact” activator of the KKS. Surprisingly, although DXS was inert for at least 30 min, a subtle MC-driven leakage resulted in factor XII (FXII-dependent activation of the KKS, which then amplified inflammation via generation of bradykinin (BK. Guided by this mechanistic insight, we next exposed TCTs to “leaky” HCP—forged by low dose histamine application—and found that the proinflammatory phenotype of TCTs was boosted by BK generated via the MC/KKS pathway. Measurements of footpad edema in MC-deficient mice linked TCT-evoked inflammation to MC degranulation (upstream and FXII-mediated generation of BK (downstream. We then inoculated TCTs intracardiacally in mice and found a striking decrease of parasite DNA (quantitative polymerase chain reaction; 3 d.p.i. in the heart of MC-deficient mutant mice. Moreover, the intracardiac parasite load was significantly reduced in WT

  1. Relation of ventricular premature beats to underlying heart disease.

    Science.gov (United States)

    Uretz, E F; Denes, P; Ruggie, N; Vasilomanolakis, E; Messer, J V

    1984-03-01

    The relation between ventricular premature beats (VPBs) and physiologic disease was investigated in 305 patients who had 24-hour Holter monitoring tests, cardiac catheterization and angiography. Both frequency and Lown class of VPBs were measured. Analyses showed that occurrence of VPBs at an average frequency of more than 2 per hour or occurrence of complex VPBs (Lown class greater than 2) have the highest association with the presence and severity of cardiac disease. Using these criteria, VPB severity was then compared with extent of ventricular wall motion abnormality (right anterior oblique projection segments), ejection fraction, end-diastolic pressure, category of disease (normal, coronary artery disease [CAD], valvular heart disease, dilated cardiomyopathy), age and severity of CAD (major coronary arteries with greater than 75% diameter reduction). Severe VPBs defined either by complexity or frequency were significantly correlated with extent of wall motion abnormality, ejection fraction, category of disease and age. Severe VPBs were not significantly correlated with end-diastolic pressure or severity of CAD. Discriminant analysis then showed that in addition to wall motion abnormality and ejection fraction, category of disease and age are independently correlated with VPB severity.

  2. Non-heart-beating donation: current state of the art.

    Science.gov (United States)

    Arias-Diaz, J; Alvarez, J; del Barrio, M R; Balibrea, J L

    2004-09-01

    The use of non-heart-beating donors (NHBD) helps us to deal with the problem of the organ shortage. In addition to difficulties with legal and ethical acceptability, there are concerns regarding medical safety, which prevent the widespread use of these donors. To make optimum use of this potential organ supply, the ischemic injury that occurs after a period of warm ischemia needs to be reversed. To minimize the warm ischemia time, once the subject is declared dead, most centers commence in situ cold perfusion via a femoral access or a rapid aortic cannulation. This usually occurs within minutes of arriving at the emergency department, before the next of kin have been notified of the patient's death. The European experience of kidney transplantation from NHBD shows promising results. The long-term outcomes are similar to HBD kidneys notwithstanding a higher rate of delayed graft function, which seems not to affect the long-term survival of these kidneys. In summary, NHBD may have an important impact on the large discrepancy that exists between the organ supply and the demand. Current data suggest that the results may be further improved by better patient selection and retrieval team organization.

  3. Estimating 'lost heart beats' rather than reductions in heart rate during the intubation of critically-ill children.

    Directory of Open Access Journals (Sweden)

    Peter Jones

    Full Text Available PURPOSE: Reductions in heart rate occur frequently in children during critical care intubation and are currently considered the gold standard for haemodynamic instability. Our objective was to estimate loss of heart beats during intubation and compare this to reduction in heart rate alone whilst testing the impact of atropine pre-medication. METHODS: Data were extracted from a prospective 2-year cohort study of intubation ECGs from critically ill children in PICU/Paediatric Transport. A three step algorithm was established to exclude variation in pre-intubation heart rate (using a 95%CI limit derived from pre-intubation heart rate variation of the children included, measure the heart rate over time and finally the estimate the numbers of lost beats. RESULTS: 333 intubations in children were eligible for inclusion of which 245 were available for analysis (74%. Intubations where the fall in heart rate was less than 50 bpm were accompanied almost exclusively by less than 25 lost beats (n = 175, median 0 [0-1]. When there was a reduction of >50 bpm there was a poor correlation with numbers of lost beats (n = 70, median 42 [15-83]. During intubation the median number of lost beats was 8 [1]-[32] when atropine was not used compared to 0 [0-0] when atropine was used (p50 bpm the heart rate was poorly predictive of lost beats. A study looking at the relationship between lost beats and cardiac output needs to be performed. Atropine reduces both fall in heart rate and loss of beats. Similar area-under-the-curve methodology may be useful for estimating risk when biological parameters deviate outside normal range.

  4. Probabilistic model-based approach for heart beat detection.

    Science.gov (United States)

    Chen, Hugh; Erol, Yusuf; Shen, Eric; Russell, Stuart

    2016-09-01

    Nowadays, hospitals are ubiquitous and integral to modern society. Patients flow in and out of a veritable whirlwind of paperwork, consultations, and potential inpatient admissions, through an abstracted system that is not without flaws. One of the biggest flaws in the medical system is perhaps an unexpected one: the patient alarm system. One longitudinal study reported an 88.8% rate of false alarms, with other studies reporting numbers of similar magnitudes. These false alarm rates lead to deleterious effects that manifest in a lower standard of care across clinics. This paper discusses a model-based probabilistic inference approach to estimate physiological variables at a detection level. We design a generative model that complies with a layman's understanding of human physiology and perform approximate Bayesian inference. One primary goal of this paper is to justify a Bayesian modeling approach to increasing robustness in a physiological domain. In order to evaluate our algorithm we look at the application of heart beat detection using four datasets provided by PhysioNet, a research resource for complex physiological signals, in the form of the PhysioNet 2014 Challenge set-p1 and set-p2, the MIT-BIH Polysomnographic Database, and the MGH/MF Waveform Database. On these data sets our algorithm performs on par with the other top six submissions to the PhysioNet 2014 challenge. The overall evaluation scores in terms of sensitivity and positive predictivity values obtained were as follows: set-p1 (99.72%), set-p2 (93.51%), MIT-BIH (99.66%), and MGH/MF (95.53%). These scores are based on the averaging of gross sensitivity, gross positive predictivity, average sensitivity, and average positive predictivity.

  5. The Role of Echocardiography and Intracardiac Exploration in the Evaluation of Candidacy for Biventricular Repair in Patients With Borderline Left Heart Structures.

    Science.gov (United States)

    Mery, Carlos M; Nieto, R Michael; De León, Luis E; Morris, Shaine A; Zhang, Wei; Colquitt, John L; Adachi, Iki; Kane, Lauren C; Heinle, Jeffrey S; McKenzie, E Dean; Fraser, Charles D

    2017-03-01

    Predictors for single ventricle palliation (SVP) or successful biventricular repair (BVR) in patients with borderline left-side heart structures are not well defined. The goal was to evaluate the role of echocardiography and intracardiac exploration in determining feasibility of BVR. All neonates surgically treated from 1995 to 2015 with mitral valve (MV), aortic valve, or left ventricle end-diastolic dimension z score of -2 or less for whom management was controversial were included. Data were analyzed using Fisher's exact test, Kruskal-Wallis test, and Kaplan-Meier analysis. The cohort consisted of 42 patients: 7 SVP (17%) and 35 BVR (83%). Median follow-up was 7 years (range, 6 months to 18 years). Intracardiac exploration was performed in 29 patients (69%). There was poor correlation between echocardiographic and intraoperative MV measurements (intraclass correlation coefficient 0.14). Preoperative echocardiography significantly underestimated MV size in 14 patients (54%). Two BVR patients were converted to SVP, and 4 (including 1 converted patient) had cardiac-related deaths. All patients with MV greater than 8 mm on preoperative echocardiography had successful BVR. An intraoperative MV less than 8 mm and an abnormal subvalvar apparatus was present in 5 of 6 SVP (83%) and 3 of 3 (100%) failed BVR patients who had intracardiac exploration, and in only 1 of 20 successful BVR patients (5%) who had an intracardiac exploration. The decision to proceed to BVR in patients with borderline left-side heart structures should not rely strictly on echocardiographic measurements. Intracardiac exploration of the MV and subvalvar apparatus is useful before committing a patient to SVP. Patients with low MV z scores, especially those with a normal subvalvar apparatus, may undergo BVR with good outcomes. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  6. Speckle variance optical coherence tomography of blood flow in the beating mouse embryonic heart.

    Science.gov (United States)

    Grishina, Olga A; Wang, Shang; Larina, Irina V

    2017-05-01

    Efficient separation of blood and cardiac wall in the beating embryonic heart is essential and critical for experiment-based computational modelling and analysis of early-stage cardiac biomechanics. Although speckle variance optical coherence tomography (SV-OCT) relying on calculation of intensity variance over consecutively acquired frames is a powerful approach for segmentation of fluid flow from static tissue, application of this method in the beating embryonic heart remains challenging because moving structures generate SV signal indistinguishable from the blood. Here, we demonstrate a modified four-dimensional SV-OCT approach that effectively separates the blood flow from the dynamic heart wall in the beating mouse embryonic heart. The method takes advantage of the periodic motion of the cardiac wall and is based on calculation of the SV signal over the frames corresponding to the same phase of the heartbeat cycle. Through comparison with Doppler OCT imaging, we validate this speckle-based approach and show advantages in its insensitiveness to the flow direction and velocity as well as reduced influence from the heart wall movement. This approach has a potential in variety of applications relying on visualization and segmentation of blood flow in periodically moving structures, such as mechanical simulation studies and finite element modelling. Picture: Four-dimensional speckle variance OCT imaging shows the blood flow inside the beating heart of an E8.5 mouse embryo. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. A transcatheter intracardiac shunt device for heart failure with preserved ejection fraction (REDUCE LAP-HF)

    DEFF Research Database (Denmark)

    Hasenfuß, Gerd; Hayward, Chris; Burkhoff, Dan

    2016-01-01

    BACKGROUND: Heart failure with preserved ejection fraction (HFPEF) is a common, globally recognised, form of heart failure for which no treatment has yet been shown to improve symptoms or prognosis. The pathophysiology of HFPEF is complex but characterised by increased left atrial pressure......, especially during exertion, which might be a key therapeutic target. The rationale for the present study was that a mechanical approach to reducing left atrial pressure might be effective in HFPEF. METHODS: The REDUCe Elevated Left Atrial Pressure in Patients with Heart Failure (REDUCE LAP-HF) study...... eligible patients were entered into the study. IASD placement was successful in 64 patients and seemed to be safe and well tolerated; no patient had a peri-procedural or major adverse cardiac or cerebrovascular event or need for cardiac surgical intervention for device-related complications during 6 months...

  8. Detection of intra-cardiac thrombi and congestive heart failure in cats using computed tomographic angiography.

    Science.gov (United States)

    Vititoe, Kyle P; Fries, Ryan C; Joslyn, Stephen; Selmic, Laura E; Howes, Mark; Vitt, Jordan P; O'Brien, Robert T

    2018-04-16

    Arterial thromboembolism is a life-threatening condition in cats most commonly secondary to cardiac disease. Echocardiography is the reference standard to evaluate for presence of a thrombus. In humans, computed tomographic (CT) angiography is becoming widely used to detect left atrial thrombi precluding the use of sedation. The purpose of this prospective, controlled, methods comparison pilot study was threefold: (1) describe new CT angiography protocol used in awake cats with cardiac disease and congestive heart failure; (2) determine accuracy of continuous and dynamic acquisition CT angiography to identify and characterize cardiac thrombi from spontaneous echocardiographic contrast using transthoracic echocardiography as our reference standard; (3) identify known negative prognostic factors and comorbidities of the thorax that CT angiography may provide that complement or supersede echocardiographic examination. Fourteen cats with heart disease were recruited; 7 with thrombi and 7 with spontaneous echocardiographic contrast. Echocardiography and awake CT angiography were performed using a microdose of contrast. Six of 7 thrombi were identified on CT angiography as filling defects by at least one reviewer within the left auricle (n = 6) and right heart (n = 1). Highest sensitivity (71.4%) was in continuous phase and highest specificity (85.7%) was in dynamic studies with fair to moderate interobserver agreement (0.38 and 0.44). CT angiography identified prognostic cardiac information (left atrial enlargement, congestive heart failure, arterial thromboembolism) and comorbidities (suspected idiopathic pulmonary fibrosis, asthma). This study indicates CT angiography can readily identify cardiac thrombi, important prognostic information and comorbidities, and can be safely performed in cats with cardiac disease and congestive heart failure. © 2018 American College of Veterinary Radiology.

  9. A new beating-heart off-pump coronary artery bypass grafting training model

    NARCIS (Netherlands)

    Bouma, Wobbe; Kuijpers, Michiel; Bijleveld, Aanke; De Maat, Gijs E.; Koene, Bart M.; Erasmus, Michiel E.; Natour, Ehsan; Mariani, Massimo A.

    OBJECTIVES: Training models are essential in mastering the skills required for off-pump coronary artery bypass grafting (OPCAB). We describe a new, high-fidelity, effective and reproducible beating-heart OPCAB training model in human cadavers. METHODS: Human cadavers were embalmed according to the

  10. Non-heart-beating lung donation : How big is the pool?

    NARCIS (Netherlands)

    Nijkamp, Danielle M.; van der Bij, Wim; Verschuuren, Erik A. M.; Heemskerk, Martin B. A.; de Buijzer, Erwin; Erasmus, Michiel E.

    Lungs from non-heart-beating (NHB) donors are seldom used in The Netherlands despite the good quality of these organs. Based on a retrospective analysis of 162 NHB donor procedures we found that only 5% of the lungs were actually utilized, but that 30% of the lungs were suitable for transplantation.

  11. Extracting fetal heart beats from maternal abdominal recordings: selection of the optimal principal components

    International Nuclear Information System (INIS)

    Di Maria, Costanzo; Liu, Chengyu; Zheng, Dingchang; Murray, Alan; Langley, Philip

    2014-01-01

    This study presents a systematic comparison of different approaches to the automated selection of the principal components (PC) which optimise the detection of maternal and fetal heart beats from non-invasive maternal abdominal recordings. A public database of 75 4-channel non-invasive maternal abdominal recordings was used for training the algorithm. Four methods were developed and assessed to determine the optimal PC: (1) power spectral distribution, (2) root mean square, (3) sample entropy, and (4) QRS template. The sensitivity of the performance of the algorithm to large-amplitude noise removal (by wavelet de-noising) and maternal beat cancellation methods were also assessed. The accuracy of maternal and fetal beat detection was assessed against reference annotations and quantified using the detection accuracy score F1 [2*PPV*Se / (PPV + Se)], sensitivity (Se), and positive predictive value (PPV). The best performing implementation was assessed on a test dataset of 100 recordings and the agreement between the computed and the reference fetal heart rate (fHR) and fetal RR (fRR) time series quantified. The best performance for detecting maternal beats (F1 99.3%, Se 99.0%, PPV 99.7%) was obtained when using the QRS template method to select the optimal maternal PC and applying wavelet de-noising. The best performance for detecting fetal beats (F1 89.8%, Se 89.3%, PPV 90.5%) was obtained when the optimal fetal PC was selected using the sample entropy method and utilising a fixed-length time window for the cancellation of the maternal beats. The performance on the test dataset was 142.7 beats 2 /min 2 for fHR and 19.9 ms for fRR, ranking respectively 14 and 17 (out of 29) when compared to the other algorithms presented at the Physionet Challenge 2013. (paper)

  12. Separation of Beating Cardiac Myocytes from Suspensions of Heart Cells

    Science.gov (United States)

    Pretlow, Thomas G.; Glick, Melvin R.; Reddy, William J.

    1972-01-01

    Heart cells were obtained in suspension after incubation with collagenase and hyaluronidase in Saline A. Cardiac myocytes were separated by isopycnic centrifugation in 88.6 to 92.4% purity from other heart cells with different densities, and by velocity or rate-zonal sedimentation, in 92.8 to 97.4% purity from heart cells with different diameters. A previously described computer integration of the differential sedimentation equation was used to determine the centrifugal force, duration of centrifugation and gradient design, which would permit the separation of cardiac myocytes from other heart cells by velocity sedimentation. The myocytes continued to contract rhythmically after being recovered from the density gradients. Velocity sedimentation was superior to isopycnic sedimentation for the separation of cardiac myocytes from heart cell suspensions because it gave the most highly purified myocytes, resulted in recovery of the largest proportion of myocytes in purified fractions from the gradient and required lower centrifugal forces for shorter periods of time. The potential significance of the availability of pure cardiac myocytes is discsused. ImagesFig 2Fig 1 PMID:4336547

  13. Agile and Bright Intracardiac Catheters

    NARCIS (Netherlands)

    M. Pekař (Martin)

    2017-01-01

    markdownabstractIntracardiac imaging catheters represent unique instruments to diagnose and treat a diseased heart. While there are imminent advances in medical innovation, many of the commercially available imaging catheters are outdated. Some of them have been designed more than 20 years and

  14. Neuro-adaptive control in beating heart surgery based on the viscoelastic tissue model

    Directory of Open Access Journals (Sweden)

    Setareh Rezakhani

    2014-04-01

    Full Text Available In this paper, the problem of 3D heart motion in beating heart surgery is resolved by proposing a parallel force-motion controller. Motion controller is designed based on neuro-adaptive approach to compensate 3D heart motion and deal with uncertainity in dynamic parameters, while an implicit force control is implemented by considering a viscoelastic tissue model. Stability analysis is proved through Lypanov’s stability theory and Barballet’s lemma. Simulation results, for D2M2 robot, which is done in nominal case and viscoelastic parameter mismatches demonstrate the robust performance of the controller.

  15. Assessment of intracardiac flow and vorticity in the right heart of patients after repair of tetralogy of Fallot by flow-sensitive 4D MRI

    International Nuclear Information System (INIS)

    Hirtler, Daniel; Garcia, Julio; Barker, Alex J.; Geiger, Julia

    2016-01-01

    To comprehensively and quantitatively analyse flow and vorticity in the right heart of patients after repair of tetralogy of Fallot (rTOF) compared with healthy volunteers. Time-resolved flow-sensitive 4D MRI was acquired in 24 rTOF patients and 12 volunteers. Qualitative flow evaluation was based on consensus reading of two observers. Quantitative analysis included segmentation of the right atrium (RA) and ventricle (RV) in a four-chamber view to extract volumes and regional haemodynamic information for computation of regional mean and peak vorticity. Right heart intra-atrial, intraventricular and outflow tract flow patterns differed considerably between rTOF patients and volunteers. Peak RA and mean RV vorticity was significantly higher in patients (p = 0.02/0.05). Significant negative correlations were found between patients' maximum and mean RV and RA vorticity and ventricular volumes (p < 0.05). The main pulmonary artery (MPA) regurgitant flow was associated with higher RA and RV vorticity, which was significant for RA maximum and RV mean vorticity (p = 0.01/0.03). The calculation of vorticity based on 4D flow data is an alternative approach to assess intracardiac flow changes in rTOF patients compared with qualitative flow visualization. Alterations in intracardiac vorticity could be relevant with regard to the development of RV dilation and impaired function. (orig.)

  16. Assessment of intracardiac flow and vorticity in the right heart of patients after repair of tetralogy of Fallot by flow-sensitive 4D MRI

    Energy Technology Data Exchange (ETDEWEB)

    Hirtler, Daniel [University Hospital Freiburg, Department of Congenital Heart Defects and Pediatric Cardiology (Heart Center, University of Freiburg), Freiburg (Germany); Garcia, Julio; Barker, Alex J. [Northwestern University Feinberg School of Medicine, Department of Radiology, Chicago, IL (United States); Geiger, Julia [University Childrens' Hospital Zurich, Department of Radiology, Zurich (Switzerland)

    2016-10-15

    To comprehensively and quantitatively analyse flow and vorticity in the right heart of patients after repair of tetralogy of Fallot (rTOF) compared with healthy volunteers. Time-resolved flow-sensitive 4D MRI was acquired in 24 rTOF patients and 12 volunteers. Qualitative flow evaluation was based on consensus reading of two observers. Quantitative analysis included segmentation of the right atrium (RA) and ventricle (RV) in a four-chamber view to extract volumes and regional haemodynamic information for computation of regional mean and peak vorticity. Right heart intra-atrial, intraventricular and outflow tract flow patterns differed considerably between rTOF patients and volunteers. Peak RA and mean RV vorticity was significantly higher in patients (p = 0.02/0.05). Significant negative correlations were found between patients' maximum and mean RV and RA vorticity and ventricular volumes (p < 0.05). The main pulmonary artery (MPA) regurgitant flow was associated with higher RA and RV vorticity, which was significant for RA maximum and RV mean vorticity (p = 0.01/0.03). The calculation of vorticity based on 4D flow data is an alternative approach to assess intracardiac flow changes in rTOF patients compared with qualitative flow visualization. Alterations in intracardiac vorticity could be relevant with regard to the development of RV dilation and impaired function. (orig.)

  17. Robust detection of heart beats in multimodal records using slope- and peak-sensitive band-pass filters.

    Science.gov (United States)

    Pangerc, Urška; Jager, Franc

    2015-08-01

    In this work, we present the development, architecture and evaluation of a new and robust heart beat detector in multimodal records. The detector uses electrocardiogram (ECG) signals, and/or pulsatile (P) signals, such as: blood pressure, artery blood pressure and pulmonary artery pressure, if present. The base approach behind the architecture of the detector is collecting signal energy (differentiating and low-pass filtering, squaring, integrating). To calculate the detection and noise functions, simple and fast slope- and peak-sensitive band-pass digital filters were designed. By using morphological smoothing, the detection functions were further improved and noise intervals were estimated. The detector looks for possible pacemaker heart rate patterns and repairs the ECG signals and detection functions. Heart beats are detected in each of the ECG and P signals in two steps: a repetitive learning phase and a follow-up detecting phase. The detected heart beat positions from the ECG signals are merged into a single stream of detected ECG heart beat positions. The merged ECG heart beat positions and detected heart beat positions from the P signals are verified for their regularity regarding the expected heart rate. The detected heart beat positions of a P signal with the best match to the merged ECG heart beat positions are selected for mapping into the noise and no-signal intervals of the record. The overall evaluation scores in terms of average sensitivity and positive predictive values obtained on databases that are freely available on the Physionet website were as follows: the MIT-BIH Arrhythmia database (99.91%), the MGH/MF Waveform database (95.14%), the augmented training set of the follow-up phase of the PhysioNet/Computing in Cardiology Challenge 2014 (97.67%), and the Challenge test set (93.64%).

  18. Dual-source CT coronary angiography in patients with premature heart-beats: initial experience

    International Nuclear Information System (INIS)

    Wang Yining; Zhang Zhuhua; Kong Lingyan; Song Lan; Mu Wenbin; Wang Yun; Jin Zhengyu

    2008-01-01

    Objective: To evaluate the feasibility of dual-source computed tomography (DSCT) coronary angiography in a population with premature heart-beats. Methods: Seventy patients with suspected coronary artery disease and premature heart-beats were routinely imaged on a DSCT scanner (Somatom Definition, Siemens AG, Germany). The images were reconstmcted before and after ECG editing. Two readers independently assessed image quality of all coronary segments using a four-point grading scale from excellent (1) to non-assessable (4). The results of the two groups were compared with a paired t-test, and a P value of less than 0.05 was considered significant. Results: The mean heart rate during examination ranged from 49 to 111 bpm[ mean(70.7±12.4) bpm]. Twenty-eight of 70 patients with relatively small variability of the heart rate [(41.0±18.4) bpm] got diagnostic image quality without ECG editing. In other 42 patients with larger variability of the heart rate [(71.4±28.7) bpm], the mean image quality scores were 2.09±1.27 and 1.50±0.79 before and after ECG editing, there was a significant difference (t= 13.764, P 2 =121.846, P<0.01). Finally, the diagnostic image accounted 98.0% (1014/1035) in all segments of 70 patients. Conclusion: DSCT can provide diagnostic images for patients with premature heart-beats. The image quality in patients with larger variability of the heart rate can be significantly improved through ECG editing. (authors)

  19. Surgical treatment of post-infarct left ventricular pseudoaneurysm with on-pump beating heart technique.

    Science.gov (United States)

    Korkmaz, Kemal; Lafçi, Gökhan; Gedik, Hikmet Selçuk; Budak, Ali Baran; Yener, Ali Ümit; Ecevit, Ata Niyazi; Yalçinkaya, Adnan; Kadiroğullari, Ersin; Çağli, Kerim

    2014-01-01

    Left ventricular pseudo-aneurysms develop when cardiac rupture is contained by pericardial adhesions or scar tissue due to myocardial infarction, surgery, trauma or infection. Left ventricular pseudo-aneurysms are uncommon, difficult to diagnose and prone to cardiac rupture. Urgent surgical repair is recommended. Here we report on a case of a large left ventricular pseudo-aneurysm on the anterolateral wall due to a previous anterior myocardial infarction, and its successful repair using the on-pump beating-heart technique.

  20. Resection of left anterior descending coronary artery aneurysm on a beating heart.

    Science.gov (United States)

    Misthos, P; Kokotsakis, J N; Lioulias, A G; Skouteli, E A

    2009-01-01

    We report on the case of a 65-year-old man with unstable angina due to a left anterior descending (LAD) coronary artery single aneurysm. On a beating heart, the aneurysm was partially resected and the left internal thoracic artery was grafted in situ as a patch to the LAD opening. The patient remains well and free of symptoms two years after the operation.

  1. Control, synchronization, and enhanced reliability of aperiodic oscillations in the Mercury Beating Heart system

    Science.gov (United States)

    Kumar, Pawan; Parmananda, P.

    2018-04-01

    Experiments involving the Mercury Beating Heart (MBH) oscillator, exhibiting irregular (aperiodic) dynamics, are performed. In the first set of experiments, control over irregular dynamics of the MBH oscillator was obtained via a superimposed periodic voltage signal. These irregular (aperiodic) dynamics were recovered once the control was switched off. Subsequently, two MBH oscillators were coupled to attain synchronization of their aperiodic oscillations. Finally, two uncoupled MBH oscillators were subjected, repeatedly, to a common stochastic forcing, resulting in an enhancement of their mutual phase correlation.

  2. Autoregulation of coronary blood flow in the isolated beating pig heart.

    Science.gov (United States)

    Schampaert, Stéphanie; van 't Veer, Marcel; Rutten, Marcel C M; van Tuijl, Sjoerd; de Hart, Jurgen; van de Vosse, Frans N; Pijls, Nico H J

    2013-08-01

    The isolated beating pig heart model is an accessible platform to investigate the coronary circulation in its truly morphological and physiological state, whereas its use is beneficial from a time, cost, and ethical perspective. However, whether the coronary autoregulation is still intact is not known. Here, we study the autoregulation of coronary blood flow in the working isolated pig heart in response to brief occlusions of the coronary artery, to step-wise changes in left ventricular loading conditions and contractile states, and to pharmacologic vasodilating stimuli. Six slaughterhouse pig hearts (473 ± 40 g) were isolated, prepared, and connected to an external circulatory system. Through coronary reperfusion and controlled cardiac loading, physiological cardiac performance was achieved. After release of a coronary occlusion, coronary blood flow rose rapidly to an equal (maximum) level as the flow during control beats, independent of the duration of occlusion. Moreover, a linear relation was found between coronary blood flow and coronary driving pressure for a wide variation of preload, afterload, and contractility. In addition, intracoronary administration of papaverine did not yield a transient increase in blood flow indicating the presence of maximum coronary hyperemia. Together, this indicates that the coronary circulation in the isolated beating pig heart is in a permanent state of maximum hyperemia. This makes the model excellently suitable for testing and validating cardiovascular devices (i.e., heart valves, stent grafts, and ventricular assist devices) under well-controlled circumstances, whereas it decreases the necessity of sacrificing large mammalians for performing classical animal experiments. © 2013, Copyright the Authors. Artificial Organs © 2013 Wiley Periodicals, Inc. and International Center for Artificial Organs and Transplantation.

  3. Position Estimation of an Epicardial Crawling Robot on the Beating Heart by Modeling of Physiological Motion

    Science.gov (United States)

    Wood, Nathan A.; del Agua, Diego Moral; Zenati, Marco A.; Riviere, Cameron N.

    2012-01-01

    HeartLander, a small mobile robot designed to provide treatments to the surface of the beating heart, overcomes a major difficulty of minimally invasive cardiac surgery, providing a stable operating platform. This is achieved inherently in the way the robot adheres to and crawls over the surface of the heart. This mode of operation does not require physiological motion compensation to provide this stable environment; however, modeling of physiological motion is advantageous in providing more accurate position estimation as well as synchronization of motion to the physiological cycles. The work presented uses an Extended Kalman Filter framework to estimate parameters of non-stationary Fourier series models of the motion of the heart due to the respiratory and cardiac cycles as well as the position of the robot as it moves over the surface of the heart. The proposed method is demonstrated in the laboratory with HeartLander operating on a physiological motion simulator. Improved performance is demonstrated in comparison to the filtering methods previously used with HeartLander. The use of detected physiological cycle phases to synchronize locomotion of HeartLander is also described. PMID:23066511

  4. Experimental small bowel transplantation from non-heart-beating donors: a large-animal study.

    Science.gov (United States)

    Cobianchi, L; Zonta, S; Vigano, J; Dominioni, T; Ciccocioppo, R; Morbini, P; Bottazzi, A; Mazzilli, M; De Martino, M; Vicini, E; Filisetti, C; Botrugno, I; Dionigi, P; Alessiani, M

    2009-01-01

    The shortage of organs in the last 20 years is stimulating the development of new strategies to expand the pool of donors. The harvesting of a graft from non-heart-beating donors (NHBDs) has been successfully proposed for kidney and liver transplantation. To our knowledge, no studies are available for small bowel transplantation using NHBDs. In an experimental setting of small bowel transplantation, we studied the feasibility of using intestinal grafts retrieved from NHBDs. Twenty five Large White piglets underwent total orthotopic small bowel transplantation and were randomly divided as follow: NHBD group (n = 15) received grafts from NHBDs; heart-beating donor (HBD) group (n = 10) received grafts from HBDs. The NHBD pigs were sacrificed inducing the cardiac arrest by a lethal potassium injection. After 20 minutes (no touch period = warm ischemia), they underwent cardiac massage, laparotomy, and aorta cannulation for flushing and cooling the abdominal organs. In HBDs, the cardiac arrest was induced at the time of organ cold perfusion. In both groups, immunosuppression was based on tacrolimus oral monotherapy. The animals were observed for 30 days. The graft absorptive function was studied at day 30 using the D-xylose absorption test. Histological investigation included HE (Hematoxilin and Eosin) microscopical analysis and immunohistological staining. Animals in the NHBD group died due to infection (n = 3), acute cellular rejection (n = 2), technical complications (n = 2), and intestinal failure (n = 8). In the HBD group, all animals but two were alive at the end of the study. The D-xylose absorption was significantly lower among the NHBD compared with the HBD group (P intestinal mucosa is sensitive to ischemic injury. When the intestinal graft is harvested from NHBDs, the infectious-related mortality was higher and the absorptive function lower. Histological examination confirmed a higher grade of ischemic injury in the NHBD grafts that correlated with the

  5. A New UK 2006 National Kidney Allocation Scheme for deceased heart-beating donor kidneys.

    Science.gov (United States)

    Johnson, Rachel J; Fuggle, Susan V; Mumford, Lisa; Bradley, J Andrew; Forsythe, John L R; Rudge, Chris J

    2010-02-27

    In 2004, it was agreed that a new allocation scheme for kidneys from deceased heart-beating donors was required in the United Kingdom to address observed inequities in access to transplant. The 2006 National Kidney Allocation Scheme (2006 NKAS) was developed to meet agreed objectives and preparatory work included a review of the criteria for human leukocyte antigen (HLA) matching and simulation evidence about the effectiveness of alternative schemes. ALGORITHM FOR 2006 NKAS: The 2006 NKAS gives absolute priority to all 000 HLA-A, -B, -DR-mismatched patients and well-matched pediatric patients (inequity of access will take a number of years to address fully.

  6. Usefulness of one-stage coronary artery bypass grafting on the beating heart and abdominal aortic aneurysm repair.

    Science.gov (United States)

    Morimoto, Keisuke; Taniguchi, Iwao; Miyasaka, Shigeto; Aoki, Tetsuya; Kato, Ippei; Yamaga, Takeshi

    2004-02-01

    Abdominal aortic aneurysm (AAA) is commonly associated with coronary artery disease (CAD). Simultaneous coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB) under cardiac arrest and AAA repair may be considerably invasive. Recently CABG under the beating heart without CPB has been reported as a less invasive method. We report the combined operation of CABG on a beating heart and AAA repair for AAA patients with CAD, and compare it with a separate operation. A retrospective review of the records of consecutive patients who underwent elective combined procedure or single operation for CABG on a beating heart and/or repair of the AAA between May 1999 and October 2001 was carried out. Ten patients underwent combined procedures. A single operation, CABG on a beating heart or repair of AAA, were performed in 27 or 19 patients. There were no significant differences with regard to intraoperative blood loss, transfusion and postoperative intubation time among the three groups. There was no operative mortality for any of the three groups. All cases were discharged without severe complications and with patent coronary bypass grafts. There was a decrease in mean total hospital costs for the combined operation group compared with the CABG group plus AAA repair group (3.34 million versus 5.87 million yen). Combined CABG on a beating heart and AAA repair on a one-step approach appears to be a safe and useful therapeutic strategy for AAA patients with CAD.

  7. Robust algorithm to locate heart beats from multiple physiological waveforms by individual signal detector voting.

    Science.gov (United States)

    Galeotti, Loriano; Scully, Christopher G; Vicente, Jose; Johannesen, Lars; Strauss, David G

    2015-08-01

    Alarm fatigue is a top medical device hazard in patient monitoring that could be reduced by merging physiological information from multiple sensors, minimizing the impact of a single sensor failing. We developed a heart beat detection algorithm that utilizes multi-modal physiological signals (e.g. electrocardiogram, blood pressure, stroke volume, photoplethysmogram and electro-encephalogram) by merging the heart beats obtained from signal-specific detectors. We used the PhysioNet/Computing in Cardiology Challenge 2014 training set to develop the algorithm, and we refined it with a mix of signals from the multiparameter intelligent monitoring in intensive care (MIMIC II) database and artificially disrupted waveforms. The algorithm had an average sensitivity of 95.67% and positive predictive value (PPV) of 92.28% when applied to the PhysioNet/Computing in Cardiology Challenge 2014 200 record training set. On a refined dataset obtained by removing 5 records with arrhythmias and inconsistent reference annotations we obtained an average sensitivity of 97.43% and PPV of 94.17%. Algorithm performance was assessed with the Physionet Challenge 2014 test set that consisted of 200 records (each up to 10 min length) containing multiple physiological signals and reference annotations verified by the PhysioNet/Computing in Cardiology Challenge 2014 organizers. Our algorithm had a sensitivity of 92.74% and PPV of 87.37% computed over all annotated beats, and a record average sensitivity of 91.08%, PPV of 86.96% and an overall score (average of all 4 measures) of 89.53%. Our algorithm is an example of a data fusion approach that can improve patient monitoring and reduce false alarms by reducing the effect of individual signal failures.

  8. Development of a high fidelity pressurized porcine beating heart simulator for cardiac surgery training.

    Science.gov (United States)

    Ribeiro, Igo B; Ngu, Janet M C; Gill, Gurinder; Rubens, Fraser D

    2017-10-01

    Development of a high-fidelity cardiac surgery simulator (CSS) requires integration of a heart model with a mock cardiopulmonary bypass (CPB) circuit that can provide feedback to mimic the pathophysiology of cardiac surgery. However, the cost of commercially available simulators precludes regular use. We describe steps in the construction of a high-fidelity CSS that integrates a pulsatile paracorporeal ventricular-assist device (Pulse-VAD) and a commercially available CPB simulator. Eight porcine hearts were initially prepared. The configuration consisted of cannulation of the distal descending aorta and the inferior vena cava to enable pressurization of the heart after connection to the Califia ® simulator, as well as Pulse-VAD cannulation (fitted with inflatable balloons) of both ventricles. After each simulation run, the team addressed key issues to derive successive model changes through consensus. Key modifications included: a) pressure maintenance of the cardiac chambers (removal of lungs, Pulse-VAD cannulation sites at the left pulmonary artery and vein, double ligation of arch vessels); b) high-fidelity beating of both ventricles (full Pulse-VAD bladder filling and ensuring balloon neck placement at the valvular plane) and c) reproducible management of porcine anatomy (management of porcine aorta, ligation of left azygous vein and shortened ascending thoracic aortic segment). A CSS can be prepared at low cost, with integration into a high-fidelity CPB simulator with a novel beating heart component. This setup can be used in teaching the basics of CPB techniques and complex surgical procedures. Future work is needed to validate this model as a simulation instrument.

  9. Development of an Ex Vivo, Beating Heart Model for CT Myocardial Perfusion.

    Science.gov (United States)

    Pelgrim, Gert Jan; Das, Marco; Haberland, Ulrike; Slump, Cees; Handayani, Astri; van Tuijl, Sjoerd; Stijnen, Marco; Klotz, Ernst; Oudkerk, Matthijs; Wildberger, Joachim E; Vliegenthart, Rozemarijn

    2015-01-01

    To test the feasibility of a CT-compatible, ex vivo, perfused porcine heart model for myocardial perfusion CT imaging. One porcine heart was perfused according to Langendorff. Dynamic perfusion scanning was performed with a second-generation dual source CT scanner. Circulatory parameters like blood flow, aortic pressure, and heart rate were monitored throughout the experiment. Stenosis was induced in the circumflex artery, controlled by a fractional flow reserve (FFR) pressure wire. CT-derived myocardial perfusion parameters were analysed at FFR of 1 to 0.10/0.0. CT images did not show major artefacts due to interference of the model setup. The pacemaker-induced heart rhythm was generally stable at 70 beats per minute. During most of the experiment, blood flow was 0.9-1.0 L/min, and arterial pressure varied between 80 and 95 mm/Hg. Blood flow decreased and arterial pressure increased by approximately 10% after inducing a stenosis with FFR ≤ 0.50. Dynamic perfusion scanning was possible across the range of stenosis grades. Perfusion parameters of circumflex-perfused myocardial segments were affected at increasing stenosis grades. An adapted Langendorff porcine heart model is feasible in a CT environment. This model provides control over physiological parameters and may allow in-depth validation of quantitative CT perfusion techniques.

  10. Ultrasound functional imaging in an ex vivo beating porcine heart platform

    Science.gov (United States)

    Petterson, Niels J.; Fixsen, Louis S.; Rutten, Marcel C. M.; Pijls, Nico H. J.; van de Vosse, Frans N.; Lopata, Richard G. P.

    2017-12-01

    In recent years, novel ultrasound functional imaging (UFI) techniques have been introduced to assess cardiac function by measuring, e.g. cardiac output (CO) and/or myocardial strain. Verification and reproducibility assessment in a realistic setting remain major issues. Simulations and phantoms are often unrealistic, whereas in vivo measurements often lack crucial hemodynamic parameters or ground truth data, or suffer from the large physiological and clinical variation between patients when attempting clinical validation. Controlled validation in certain pathologies is cumbersome and often requires the use of lab animals. In this study, an isolated beating pig heart setup was adapted and used for performance assessment of UFI techniques such as volume assessment and ultrasound strain imaging. The potential of performing verification and reproducibility studies was demonstrated. For proof-of-principle, validation of UFI in pathological hearts was examined. Ex vivo porcine hearts (n  =  6, slaughterhouse waste) were resuscitated and attached to a mock circulatory system. Radio frequency ultrasound data of the left ventricle were acquired in five short axis views and one long axis view. Based on these slices, the CO was measured, where verification was performed using flow sensor measurements in the aorta. Strain imaging was performed providing radial, circumferential and longitudinal strain to assess reproducibility and inter-subject variability under steady conditions. Finally, strains in healthy hearts were compared to a heart with an implanted left ventricular assist device, simulating a failing, supported heart. Good agreement between ultrasound and flow sensor based CO measurements was found. Strains were highly reproducible (intraclass correlation coefficients  >0.8). Differences were found due to biological variation and condition of the hearts. Strain magnitude and patterns in the assisted heart were available for different pump action, revealing

  11. Sudden cardiac death in dogs with remodeled hearts is associated with larger beat-to-beat variability of repolarization

    DEFF Research Database (Denmark)

    Thomsen, Morten Bækgaard; Truin, Michiel; van Opstal, Jurren M

    2005-01-01

    Increased proarrhythmia in dogs with chronic AV block (AVB) has been explained by ventricular remodeling causing a decrease in repolarization reserve. Beat-to-beat variability of repolarization (BVR) has been suggested to reflect repolarization reserve, in which high variability represents...... diminished reserve and larger propensity for repolarization-dependent ventricular arrhythmia. A subset of chronic AVB dogs (10%) suffers sudden cardiac death (SCD). With the assumption that repolarization defects constitute a potentially lethal proarrhythmic substrate, we hypothesized that BVR in SCD dogs...... are larger than in matched control chronic AVB dogs. From a population of 200 chronic AVB dogs, initially two groups were chosen retrospectively: 8 dogs that died suddenly (SCD) and 8 control dogs. Control dogs had a longer lifespan after AVB (10 to 18 weeks) than SCD dogs (5 to 10 weeks). All dogs had...

  12. Liver transplantation from Maastricht category 2 non-heart-beating donors.

    Science.gov (United States)

    Otero, Alejandra; Gómez-Gutiérrez, Manuel; Suárez, Francisco; Arnal, Francisco; Fernández-García, Antón; Aguirrezabalaga, Javier; García-Buitrón, José; Alvarez, Joaquín; Máñez, Rafael

    2003-10-15

    The demand for liver transplantation has increasingly exceeded the supply of cadaver donor organs. Non-heart-beating donors (NHBDs) may be an alternative to increase the cadaver donor pool. The outcome of 20 liver transplants from Maastricht category 2 NHBDs is compared with 40 liver transplants from heart-beating donors (HBDs). After unsuccessful cardiopulmonary resuscitation (CPR), cardiopulmonary support (CPS) with simultaneous application of chest and abdominal compression (n=6), and cardiopulmonary bypass (CPB; n=14), which was hypothermic (n=7) or normothermic (n=7), were used to preserve the organs from NHBDs. Factors that may influence the outcome of livers from Maastricht category 2 NHBDs were also investigated. With a minimum follow-up of 2 years, actuarial patient and graft survivals with livers from Maastricht category 2 NHBDs were 80% and 55%, respectively. Transplantation of organs from these donors was associated with a significantly higher incidence of primary nonfunction, biliary complications, and more severe initial liver dysfunction compared with livers from HBDs. Graft survival was 83% in livers from NHBDs preserved with CPS and 42% in those maintained with CPB. No graft failed if the duration of warm ischemia did not exceed 130 min with CPR or CPS, and if the period of CPB did not surpass 150 min when this method was used after CPR, regardless if it was hypothermic or normothermic. Livers from Maastricht type 2 NHBDs may be used for transplantation if the period of warm ischemia during CPR or CPS does not exceed 130 min. Hypothermic or normothermic CPB after CPR preserves liver viability for an additional 150 min.

  13. Are we ready to utilize non-heart-beating donors for clinical allotransplantation in China?

    Science.gov (United States)

    Liu, Z; Zhu, B; Yun, P; Wang, P; Wang, X; Xu, H

    2008-05-01

    The concept of brain death has not been accepted by the majority of Chinese. Importantly, it is not recognized as a legal entity. We have developed a non-heart-beating donation protocol based on literature searches (Medline, Ovid, and CNKI) and issues related to Chinese customs and ethics. The principles guiding protocol development included: separation of the decision to terminate life support from the donation decision, family-centered donation, freedom of conflict interest, and prohibition of organ sales. This protocol covers donation policy, potential donor identification and evaluation, family consent, determination of death, procurement, and special legal documents/organ distribution policy. A random survey was performed regarding donation. There have been several arguments about the development of this protocol. First, do donor family members have the right to make a decision to withdraw life support? Another issue is whether family members have the right to consent to donation without a will from the donor. Our survey found that over 96.1% of people do not have a will and have not discussed their interests in donation with family members. The last issue is whether the hospital can financially help for the funeral after donation. We have debated these issues nationwide with various opinions. We hope to find the right solutions through international debate. We believe that the use of non-heart-beating-donor organs has potential in China. We are hopeful that it will become a major organ source that is developed in such a way so as to be accepted internationally as well as in China.

  14. Operative correction of judoists’ training loads on the base of on-line monitoring of heart beats rate

    Directory of Open Access Journals (Sweden)

    Liu Yong Qiang

    2015-02-01

    Full Text Available Purpose: ensure increase of effectiveness of training process’s control by means of operative correction of training loads of different qualification judo wrestlers’ heart beats rate indicators. Material: the research was conducted on the base of Brest SCJSOR № 1. Judo wrestlers of different sport qualification (age 17-19 years old, n=15 participated in the research. Monitoring of judo wrestlers’ heart beats rate was carried out with the help of system “Polar”. Results: we have found factorial structure of functional fitness in every profile of sportsmen. Model characteristics of judo wrestlers were supplemented with the most important sides of functional fitness. Analysis of indicators of restoration effectiveness indicators (REI in both groups of judo wrestlers showed high level of organism’s responsiveness to training load of special and power orientation in comparison with speed power load. We have worked out algorithm of operative correction of training loads by indicators of heart beats rate in training process, depending on orientation and intensity of loads’ physiological influence on judo wrestler. Conclusions: Telemetric on-line monitoring of sportsman’s heart beats rate and calculation of REI permit to objectively assess effectiveness of training’s construction and of micro-cycle in total and detect in due time the trend to development of over-loading and failure of adaptation.

  15. Operative correction of judoists’ training loads on the base of on-line monitoring of heart beats rate

    Directory of Open Access Journals (Sweden)

    Yong Qiang Liu

    2015-04-01

    Full Text Available Purpose: ensure increase of effectiveness of training process’s control by means of operative correction of training loads of different qualification judo wrestlers’ heart beats rate indicators. Material: the research was conducted on the base of Brest SCJSOR № 1. Judo wrestlers of different sport qualification (age 17-19 years old, n=15 participated in the research. Monitoring of judo wrestlers’ heart beats rate was carried out with the help of system “Polar”. Results: we have found factorial structure of functional fitness in every profile of sportsmen. Model characteristics of judo wrestlers were supplemented with the most important sides of functional fitness. Analysis of indicators of restoration effectiveness indicators (REI in both groups of judo wrestlers showed high level of organism’s responsiveness to training load of special and power orientation in comparison with speed power load. We have worked out algorithm of operative correction of training loads by indicators of heart beats rate in training process, depending on orientation and intensity of loads’ physiological influence on judo wrestler. Conclusions: Telemetric on-line monitoring of sportsman’s heart beats rate and calculation of REI permit to objectively assess effectiveness of training’s construction and of micro-cycle in total and detect in due time the trend to development of over-loading and failure of adaptation.

  16. Quality metrics for high order meshes: analysis of the mechanical simulation of the heart beat.

    Science.gov (United States)

    Lamata, Pablo; Roy, Ishani; Blazevic, Bojan; Crozier, Andrew; Land, Sander; Niederer, Steven A; Hose, D Rod; Smith, Nicolas P

    2013-01-01

    The quality of a computational mesh is an important characteristic for stable and accurate simulations. Quality depends on the regularity of the initial mesh, and in mechanical simulations it evolves in time, with deformations causing changes in volume and distortion of mesh elements. Mesh quality metrics are therefore relevant for both mesh personalization and the monitoring of the simulation process. This work evaluates the significance, in meshes with high order interpolation, of four quality metrics described in the literature, applying them to analyse the stability of the simulation of the heart beat. It also investigates how image registration and mesh warping parameters affect the quality and stability of meshes. Jacobian-based metrics outperformed or matched the results of coarse geometrical metrics of aspect ratio or orthogonality, although they are more expensive computationally. The stability of simulations of a complete heart cycle was best predicted with a specificity of 61%, sensitivity of 85%, and only nominal differences were found changing the intra-element and per-element combination of quality values. A compromise between fitting accuracy and mesh stability and quality was found. Generic geometrical quality metrics have a limited success predicting stability, and an analysis of the simulation problem may be required for an optimal definition of quality.

  17. Simulation of the Beating Heart Based on Physically Modeling aDeformable Balloon

    Energy Technology Data Exchange (ETDEWEB)

    Rohmer, Damien; Sitek, Arkadiusz; Gullberg, Grant T.

    2006-07-18

    The motion of the beating heart is complex and createsartifacts in SPECT and x-ray CT images. Phantoms such as the JaszczakDynamic Cardiac Phantom are used to simulate cardiac motion forevaluationof acquisition and data processing protocols used for cardiacimaging. Two concentric elastic membranes filled with water are connectedto tubing and pump apparatus for creating fluid flow in and out of theinner volume to simulate motion of the heart. In the present report, themovement of two concentric balloons is solved numerically in order tocreate a computer simulation of the motion of the moving membranes in theJaszczak Dynamic Cardiac Phantom. A system of differential equations,based on the physical properties, determine the motion. Two methods aretested for solving the system of differential equations. The results ofboth methods are similar providing a final shape that does not convergeto a trivial circular profile. Finally,a tomographic imaging simulationis performed by acquiring static projections of the moving shape andreconstructing the result to observe motion artifacts. Two cases aretaken into account: in one case each projection angle is sampled for ashort time interval and the other case is sampled for a longer timeinterval. The longer sampling acquisition shows a clear improvement indecreasing the tomographic streaking artifacts.

  18. Healthcare performance and the effects of the binaural beats on human blood pressure and heart rate.

    Science.gov (United States)

    Carter, Calvin

    2008-01-01

    Binaural beats are the differences in two different frequencies (in the range of 30-1000 Hz). Binaural beats are played through headphones and are perceived by the superior olivary nucleus of each hemisphere of the brain. The brain perceives the binaural beat and resonates to its frequency (frequency following response). Once the brain is in tune with the binaural beat it produces brainwaves of that frequency altering the listener's state of mind. In this experiment, the effects of the beta and theta binaural beat on human blood pressure and pulse were studied. Using headphones, three sounds were played for 7 minutes each to 12 participants: the control,- the sound of a babbling brook (the background sound to the two binaural beats), the beta binaural beat (20 Hz), and the theta binaural beat (7 Hz). Blood pressure and pulse were recorded before and after each sound was played. Each participant was given 2 minutes in-between each sound. The results showed that the control and the two binaural beats did not affect the 12 participant's blood pressure or pulse (p > 0.05). One reason for this may be that the sounds were not played long enough for the brain to either perceive and/or resonate to the frequency. Another reason why the sounds did not affect blood pressure and pulse may be due to the participant's age since older brains may not perceive the binaural beats as well as younger brains.

  19. Liver transplantation from maastricht category 2 non-heart-beating donors: a source to increase the donor pool?

    Science.gov (United States)

    Otero, A; Gómez-Gutiérrez, M; Suárez, F; Arnal, F; Fernández-García, A; Aguirrezabalaga, J; García-Buitrón, J; Alvarez, J; Máñez, R

    2004-04-01

    The demand for liver transplantation has increasingly exceeded the supply of cadaver donor organs. Non-heart-beating donors (NHBDs) may be an alternative to increase the cadaver donor pool. The outcome of 20 liver transplants from Maastricht category 2 NHBD was compared with that of 40 liver transplants from heart-beating donors (HBDs). After unsuccessful cardiopulmonary resuscitation (CPR), cardiopulmonary support with simultaneous application of chest and abdominal compression (CPS; n = 6) or cardiopulmonary bypass (CPB; n = 14) was used to maintain the donors. At a minimum follow-up of 2 years, actuarial patient and graft survival rates with livers from Maastricht category 2 NHBD were 80% and 55%, respectively. Transplantation of organs from these donors was associated with a significantly higher incidence of primary nonfunction, biliary complications, and more severe initial liver dysfunction compared with organs from HBDs. The graft survival rates was 83% for livers from NHBDs preserved with CPS and 42% in those maintained with CPB.

  20. Heart beats rate indicators and structure of elite football referees’ and their assistants’ motor functioning in competition period

    Directory of Open Access Journals (Sweden)

    T. G. Chopilko

    2015-11-01

    Full Text Available Purpose: to analyze structure of motor functioning and heart beats rate indicators in elite football referees’ and their assistants’ competition activity. Material: in the research 15 referees and referees’ assistants of Ukrainian Prime League, 30 referees and referees’ assistants of first and second professional leagues of Ukraine participated. Observations over referees’ movements in 21 professional matches of Ukrainian professional leagues were fulfilled. Distance, passed by a referee in one match was determined. Results: It was found that during one match referee (depending on his functions - referee or referee’s assistant passes distance from 6000 to 12 000 meters. This scope of motor functioning depends also on motor activity of players and qualification level of teams-participants in the match. Motor actions of referees’ assistants change every 5 seconds during a match. During one match referee’s assistants fulfill about 20 sprints and 74 accelerations. A high temp of match total distance makes 1.2 km. Conclusions: Referees’ and referee assistants’ motor functioning and heart beats rate indicators can vary from aerobic-restoration to anaerobic-glycolytic zone. This fact shall be considered when planning program on special physical training. It should be noted that with heart beats rate of more than 180 bpm concentration of attention significantly weakens as well as ability to take prompt and correct decisions. In such cases probability of mistakes significantly increases.

  1. Development of a non-heart-beating donor program and results after the first year.

    Science.gov (United States)

    Meneses, J C; Gámez, P; Mariscal, A; Marrón, C; Díaz-Hellín, V; Cortes, M; de Pablo, A; Lopez, E; Perez, V; Gonzalez, O; Juarros, L; Martinez, I; Hermoso, F; Avila, R; Zuluaga, M; de Nicolás, J L M

    2012-09-01

    Our lung transplant unit began activity in October 2008. We have performed 37 lung transplants with a hospital mortality of 2.7% (n = 1). The need for a greater number of donors and the presence of an already existent non-heart-beating donor (NHBD) program for abdominal grafts and tissues encouraged us to consider assessing lung grafts from these donors. It was necessary to develop a new multiorgan preservation methodology, "bithermia preservation." The clinical experience with which during the first year June 2010 to July 2011, including 15 NHBDs is presented herein. The chest x-ray was normal in 6 donors (40%) and 7 had pulmonary infiltrates. Bronchoscopy was normal in 8 donors (53%) but 3 had abundant bleeding airway secretions and signs of bronchoaspiration. Preservation procedures were performed in 6 donors. Pulmonary functional evaluation in 4 donors showed gas measurements to be adequate in 75% of cases. Three double-lung grafts were judged to be valid for implantation, among which we performed 3 lung transplantations, 1 bilateral and 2 unilaterals, while 2 grafts were offered to the National Transplant Organization for other units. No transplant suffered primary graft dysfunction; all 3 showed excellent function allowing early extubation in 2 cases. There was no in-hospital mortality. All 3 patients are alive and leading normal lives; none has bronchiolitis obliterans syndrome. In conclusion, the "bithermia preservation" methodology achieved adequate lung preservation in NHBDs, allowing liver, kidneys, and lungs to be obtained from the same donor. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. [Resection of intracardiac myxoma. Case report].

    Science.gov (United States)

    Carmona-Delgado, Víctor Manuel; Deloya-Maldonado, Angélica María; Carranza-Bernal, María Lourdes; Hinojosa-Pérez, Arturo; Farías-Mayene, Leobardo

    2017-01-01

    Myxomas are the most common benign cardiac tumors, which are considered emergency surgery. The resection should not be delayed because 8-9% of affected patients may die due to intracardiac blood flow obstruction. We presente a clinical case of a 47 year old female, history of dyslipidemia. Disease starts with retrosternal oppression feeling, dyspnea on moderate exercise, dizziness, pain in joints hands. Arrhytmic heart sounds, diastolic mitral murmur II/IV, breth sounds present, no lymph. Laboratory: hemoglobin 11.0, leucocyte 9000, glucose 96 mg/dL, chest RX medium arch prominence cardiac silhouette. ECO transthoracic LVEF 60 %, with left atrial intracardiac tumor 13x11 cm, pedicle fixed the interatrial septum, the mitral valve bulges, with mild mitral valve. Half sternotomy is performed intracardiac tumor resection, pericardial placement interatrial with extracorporeal circulation support 65', aortic clamping time of 40'. Intracardiac tumor surgical findings interatrial septum fixed to left side, pedicle, rounded, yellow, multiloculated, soft, 13x10 cm in diameter. Histopathological diagnosis cardiac myxoma. We conclude that the tumor resection was carried in a timely manner with satisfactory evolution.

  3. Intracardiac leiomyomatosis: Report of two cases

    Directory of Open Access Journals (Sweden)

    Pradeep Vaideeswar

    2011-01-01

    Full Text Available Intravenous leiomyomatosis is an example of unusual growth patterns that is sometimes exhibited by uterine leiomyomas, characterized by smooth muscle proliferations within the uterine or pelvic veins. Extension into the heart via the inferior vena cava is even rarer and is designated as intracardiac leiomyomatosis. This is a report of two such cases that had preoperative diagnoses of a thrombus and right atrial myxoma, respectively.

  4. NIR spectroscopic imaging to map hemoglobin + myoglobin oxygenation, their concentration and optical pathlength across a beating pig heart during surgery.

    Science.gov (United States)

    Gussakovsky, Eugene; Yang, Yanmin; Rendell, John; Jilkina, Olga; Kupriyanov, Valery

    2012-02-01

    The purpose of this paper is to demonstrate that near-infrared (NIR) spectroscopic imaging can provide spatial distribution (maps) of the absolute concentration of hemoglobin + myoglobin, oxygen saturation parameter and optical pathlength, reporting on the biochemico-physiological status of a beating heart in vivo. The method is based on processing the NIR spectroscopic images employing a first-derivative approach. Blood-pressure-controlled gating compensated the effect of heart motion on the imaging. All the maps are available simultaneously and noninvasively at a spatial resolution in the submillimeter range and can be obtained in a couple of minutes. The equipment has no mechanical contact with the tissue, thereby leaving the heart unaffected during the measurement. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Chemical effects produced by the ionizing radiation in the mercury beating heart reaction

    International Nuclear Information System (INIS)

    Castillo-Rojas, S.; Burillo, G.; Gonzalez-Chavez, J.L.; Vicente, L.

    2002-01-01

    Complete text of publication follows. In a recent paper we have shown the existence of complex modes of oscillation in the study of the extinction dynamics of the mercury beating heart reaction. It was proposed that one of the species responsible for the oscillatory movements of this reaction is the mercury(I), in anyone in their forms, either free or molecular. the formation of Hg 2 2+ from γ irradiation of 60 Co to the system Hg 0 /H 2 SO 4 (6M) allowed to elucidate the probable mechanism of reaction. The objective of this work is to study how the ionizing radiation affects the dynamics of extinction of this reaction, which is related with the existence of certain chemical species. The study was carried out in 2 ways: a) Method I: H 2 SO 4 (6M) was first irradiated and to the irradiated solution the Hg 0 was added and b) Method II: the system Hg 0 /H 2 SO 4 (6M) was irradiated. The different irradiated systems were put into reaction with Fe 0 to investigate if there were differences between the two irradiated systems and how the complex modes of oscillation of the reaction were affected. The quantity of Hg 2 2+ produced by method I is bigger than in method II. This is explained because the majority species produced by radiolysis of H 2 SO 4 are sulfate radical and H 2 O 2 that act as oxidizer agents and their potential values allow to suppose that these substances react with Hg 0 to produce Hg 2 2+ . On the other hand, by method II mercury clusters (Hg 4 3+ ) are formed as was reported by Sukhov and Ershov in pulse radiolysis of aqueous Hg 2 2+ solutions. We assume that the formation of these mercury clusters has to be observed with the decrease of the Hg 2 2+ concentration when one makes the radiolysis by method II. In general, the preliminary studies allow establishing that the ionizing radiation does not affect the extinction dynamics but it increases the half-life of this reaction

  6. "Non Working Beating Heart": novo método de proteção miocárdica no transplante cardíaco Non Working Beating Heart: a new strategy of myocardial protection during heart transplant

    Directory of Open Access Journals (Sweden)

    Jarbas Jakson Dinkhuysen

    2011-12-01

    implantation of the donor heart in the bicaval bipulmonary orthotopic position using normothermic beating heart and thus, facilitate the transplanted heart adaptation to the recipient. This study presents a small experience about a new strategy of myocardial protection during heart transplant. METHODS: In cardiopulmonary bypass, the aorta anastomosis was done first, allowing the coronary arteries to receive blood flow and the recovering of the beats. The rest of the anastomosis is performed on a beating heart in sinus rhythm. The pulmonary anastomosis is the last to be done. This methodology was applied in 10 subjects: eight males, age 16-69 (mean 32.7 years, SPAo 90-100 mmHg (mean 96 mmHg, SPAP 25-65 mmHg (mean 46.1 mmHg, PVR 0.9 to 5.0 Wood (mean 3.17 Wood, GTP 4-13 mmHg (mean 7.9 mmHg, and eight male donors, age 15-48 years (mean 27.7 years, weight 65-114 kg (mean 83.1 kg. Causes of brain coma: encephalic trauma in five hemorrhagic stroke in four, and brain tumor in one. RESULTS: The ischemic time ranged from 58-90 minutes (mean 67.6 minutes and 8 donors were in hospitals of Sao Paulo and two in distant cities. All grafts assumed the cardiac output requiring low-dose inotropic therapy and maintained these conditions in the postoperative period. There were no deaths and all were discharged. The late evolution goes from 20 days to 10 months with one death occurred after 4 months due to sepsis. CONCLUSION: This method, besides reducing the ischemic time of the procedure, allows the donated organ to regain and maintain their beats without pre or after load during implantation entailing the physiological recovery of the graft.

  7. Preservation of Myocardial Perfusion and Function by Keeping Hypertrophied Heart Empty and Beating for Valve Surgery: An In Vivo MR Study of Pig Hearts.

    Science.gov (United States)

    Wang, Jian; Xiang, Bo; Deng, Jixian; Lin, Hung-Yu; Freed, Darren H; Arora, Rakesh C; Tian, Ganghong

    2017-01-01

    Objectives . Normothermic hyperkalemic cardioplegia arrest (NHCA) may not effectively preserve hypertrophied myocardium during open-heart surgery. Normothermic normokalemic beating perfusion (NNBP), keeping hearts empty-beating, was utilized as an alternative to evaluate its cardioprotective role. Materials and Methods . Twelve hypertrophied pig hearts at 58.6 ± 7.2 days after ascending aorta banding underwent NNBP and NHCA, respectively. Near infrared myocardial perfusion imaging with indocyanine green (ICG) was conducted to assess myocardial perfusion. Left ventricular (LV) contractile function was assessed by cine MRI. TUNEL staining and western blotting for caspase-3 cleavage and cardiac troponin I (cTnI) degradation were conducted in LV tissue samples. Results . Ascending aortic diameter was reduced by 52.7% ± 0.4% at approximately fifty-eight days after banding. LV wall thickness was significantly higher in aorta banding than in sham operation. Myocardial blood flow reflected by maximum ICG absorbance value was markedly higher in NNBP than in NHCA. The amount of apoptotic cardiomyocyte was significantly lower in NNBP than in NHCA. NNBP alleviated caspase-3 cleavage and cTnI degradation associated with NHCA. NNBP displayed a substantially increased postoperative ejection fraction relative to NHCA. Conclusions . NNBP was better than NHCA in enhancing myocardial perfusion, inhibiting cardiomyocyte apoptosis, and preserving LV contractile function for hypertrophied hearts.

  8. From beat rate variability in induced pluripotent stem cell-derived pacemaker cells to heart rate variability in human subjects.

    Science.gov (United States)

    Ben-Ari, Meital; Schick, Revital; Barad, Lili; Novak, Atara; Ben-Ari, Erez; Lorber, Avraham; Itskovitz-Eldor, Joseph; Rosen, Michael R; Weissman, Amir; Binah, Ofer

    2014-10-01

    We previously reported that induced pluripotent stem cell-derived cardiomyocytes manifest beat rate variability (BRV) resembling heart rate variability (HRV) in the human sinoatrial node. We now hypothesized the BRV-HRV continuum originates in pacemaker cells. To investigate whether cellular BRV is a source of HRV dynamics, we hypothesized 3 levels of interaction among different cardiomyocyte entities: (1) single pacemaker cells, (2) networks of electrically coupled pacemaker cells, and (3) the in situ sinoatrial node. We measured BRV/HRV properties in single pacemaker cells, induced pluripotent stem cell-derived contracting embryoid bodies (EBs), and electrocardiograms from the same individual. Pronounced BRV/HRV was present at all 3 levels. The coefficient of variance of interbeat intervals and Poincaré plot indices SD1 and SD2 for single cells were 20 times greater than those for EBs (P heart (the latter two were similar; P > .05). We also compared BRV magnitude among single cells, small EBs (~5-10 cells), and larger EBs (>10 cells): BRV indices progressively increased with the decrease in the cell number (P heart rhythm. The decreased BRV magnitude in transitioning from the single cell to the EB suggests that the HRV of in situ hearts originates from the summation and integration of multiple cell-based oscillators. Hence, complex interactions among multiple pacemaker cells and intracellular Ca(2+) handling determine HRV in humans and cardiomyocyte networks. Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  9. Surgical on-pump beating-heart treatment of ischemic patients with low LF ejection fraction: immediate results

    Directory of Open Access Journals (Sweden)

    А. М. Чернявский

    2015-10-01

    Full Text Available Objectives. The study compares the early results of on-pump beating-heart (ONBEAT surgery versus conventional coronary artery bypass grafting (CABG with cardioplegic arrest (ONSTOP in patients with coronary artery disease and left ventricular dysfunction. Methods. In a single-center randomized trial, 60 patients operated for severe left ventricular dysfunction (EF<35% between January 2012 and January 2014 were randomized to ONBEAT (n=30 or ONSTOP (n=30 cohorts. All patients received preventive hemodynamic support before surgery (determined by randomization: intra-aortic balloon pump or levosimendan. Preoperative, operative and postoperative variables were evaluated in both groups. Results. Preoperative characteristics were similar between both groups. The time of stay in the ICU was 3 (2; 5 days in the first group and 3 (2; 4 days in the second one (p = 0.2. In the ONBEAT group 62 distal anastomoses (30 arterial were performed and in the ONSTOP group 70 distal anastomoses (30 arterial were done (p = 0.3. Completeness of revascularization on the beating heart corresponded to that in the group with cardioplegic arrest. The presence of complications such as stroke (p = 1.0, renal failure (p = 0.5, respiratory events (p = 0.2 and heart failure (p = 0.5 did not differ significantly between the two groups. Atrial fibrillation tended to occur more often in the postoperative period in the ONSTOP group (p = 0.03. The concentration of troponin I at all stages of the study did not differ significantly between the two groups. Both groups showed a significant increase in LV ejection fraction postoperatively: the first group 30 (26; 33 to 34 (30; 39 %, (p = 0,009; the second group - 31 (27 and 33 to 35 (30; 37 % (p = 0.01. Hospital mortality in the first group was observed in 1 case and in the second one in two cases (p = 0.5. Conclusions. The on-pump beating heart technique has no advantages comparing with conventional CABG in cases of preventive hemodynamic

  10. DropConnected neural networks trained on time-frequency and inter-beat features for classifying heart sounds.

    Science.gov (United States)

    Kay, Edmund; Agarwal, Anurag

    2017-07-31

    Automatic heart sound analysis has the potential to improve the diagnosis of valvular heart diseases in the primary care phase, as well as in countries where there is neither the expertise nor the equipment to perform echocardiograms. An algorithm has been trained, on the PhysioNet open-access heart sounds database, to classify heart sounds as normal or abnormal. The heart sounds are segmented using an open-source algorithm based on a hidden semi-Markov model. Following this, the time-frequency behaviour of a single heartbeat is characterized by using a novel implementation of the continuous wavelet transform, mel-frequency cepstral coefficients, and certain complexity measures. These features help detect the presence of any murmurs. A number of other features are also extracted to characterise the inter-beat behaviour of the heart sounds, which helps to recognize diseases such as arrhythmia. The extracted features are normalized and their dimensionality is reduced using principal component analysis. They are then used as the input to a fully-connected, two-hidden-layer neural network, trained by error backpropagation, and regularized with DropConnect. This algorithm achieved an accuracy of 85.2% on the test data, which placed third in the PhysioNet/Computing in Cardiology Challenge (first place scored 86.0%). However, this is unrealistic of real-world performance, as the test data contained a dataset (dataset-e) in which normal and abnormal heart sounds were recorded with different stethoscopes. A 10-fold cross-validation study on the training data (excluding dataset-e) gives a mean score of 74.8%, which is a more realistic estimate of accuracy. With dataset-e excluded from training, the algorithm scored only 58.1% on the test data.

  11. Effect of trimetazidine and glucose- insulin-potassium use on myocard during beating heart coronary artery bypass surgery

    Directory of Open Access Journals (Sweden)

    Abdulkadir Ercan

    2011-12-01

    Full Text Available Objectives: This prospective, randomised, controlled, clinical study was planned to determine the effect of trimetazidine and glucose - insulin - potassium (GIK on myocardial ischemia-reperfusion during beating heart coronary artery bypass surgery.Materials and methods: Patients (n=45 with coronary artery disease who required beating heart coronary artery bypass grafting were randomly allocated into three groups. Patients in group 1 (n=15 was recevied trimetazidine (20 mg x 3 per day 7 days before surgery. Patients in group 2 (n=15 received GIK infusion after induction of anesthesia through the first 12 hours of intensive care unit convalescence. Patients in group 3 (n=15 were control group. Measurements of blood glucose, circulating creatine kinase MB (CK-MB and Troponin I (TnI concentrations were obtained before surgery, 5 minutes after completion of operation and at 12, 24, and 48 hours postoperatively. Mean pulmonary artery pressure, cardiac index, morbidity and data associated with operation were recorded in all patients preoperatively and postoperatively.Results: Preoperative risk profiles and operative variables were statistically similar when the groups were compared. The concentration of circulating CK-MB and Tn I significantly increased over time after off - pump coronary artery surgery, with no significant intergroup differences. Cardiac index and mean pulmonary artery pressure did not differ significantly between groups.Conclusion: Pretreatment with trimetazidine and GIK infusion protocol were used as an adjunct to ischemic - reperfusion therapy in off - pump coronary artery bypass surgery. These results suggested that pretreatment with trimetazidine and GIK infusion protocol do not significantly reduce ischemic reperfusion damage.

  12. An Experimental Study in Generative Music for Exercising to Ease Perceived Exertion by use of Heart Beat Rate as a Control Parameter

    DEFF Research Database (Denmark)

    Hagensen, Troels Lunde; Serafin, Stefania; Erkut, Cumhur

    This paper investigates whether generative music, adapted to a user's heart beat rate, can be used to ease the perceived exertion. A generative system was implemented and tested on 13 test participants in a controlled environment on a training bike. The test participants performed a cycling workout...

  13. Coronary artery bypass grafting on the beating heart using the Octopus method

    NARCIS (Netherlands)

    Thijssens, K. M.; Rodrigus, I. E.; Amsel, B. J.; de Hert, S. G.; Moulijn, A. C.

    2000-01-01

    STUDY OBJECTIVE: To study the usefulness and effectiveness of off-pump coronary bypass grafting with the Octopus heart stabilizing device. METHOD: The files of thirty-one patients undergoing coronary artery bypass with the aid of the Octopus heart stabilizing device between April 1996 and October

  14. Development of an Ex Vivo, Beating Heart Model for CT Myocardial Perfusion

    NARCIS (Netherlands)

    Pelgrim, Gert Jan; Das, Marco; Haberland, Ulrike; Slump, Cees; Handayani, Astri; van Tuijl, Sjoerd; Stijnen, Marco; Klotz, Ernst; Oudkerk, Matthijs; Wildberger, Joachim E.; Vliegenthart, Rozemarijn

    2015-01-01

    Objective. To test the feasibility of a CT-compatible, ex vivo, perfused porcine heart model for myocardial perfusion CT imaging. Methods. One porcine heart was perfused according to Langendorff. Dynamic perfusion scanning was performed with a second-generation dual source CT scanner. Circulatory

  15. "And the Beat Goes Ona... Building Artificial Hearts in the Classroom.

    Science.gov (United States)

    Brock, David L.

    2000-01-01

    Among the many ideas and theories in anatomy and physiology, one particular topic provides all the potential benefits of learning about the human body: the circulatory system, specifically the heart. Describes a distinctive way to study circulation and the heart that allows students to explore the basic principles of vertebrate anatomy and…

  16. Clinical and histologic effects of intracardiac administration of propofol for induction of anesthesia in ball pythons (Python regius).

    Science.gov (United States)

    McFadden, Michael S; Bennett, R Avery; Reavill, Drury R; Ragetly, Guillaume R; Clark-Price, Stuart C

    2011-09-15

    To assess the clinical differences between induction of anesthesia in ball pythons with intracardiac administration of propofol and induction with isoflurane in oxygen and to assess the histologic findings over time in hearts following intracardiac administration of propofol. Prospective randomized study. 30 hatchling ball pythons (Python regius). Anesthesia was induced with intracardiac administration of propofol (10 mg/kg [4.5 mg/lb]) in 18 ball pythons and with 5% isoflurane in oxygen in 12 ball pythons. Induction time, time of anesthesia, and recovery time were recorded. Hearts from snakes receiving intracardiac administration of propofol were evaluated histologically 3, 7, 14, 30, and 60 days following propofol administration. Induction time with intracardiac administration of propofol was significantly shorter than induction time with 5% isoflurane in oxygen. No significant differences were found in total anesthesia time. Recovery following intracardiac administration of propofol was significantly longer than recovery following induction of anesthesia with isoflurane in oxygen. Heart tissue evaluated histologically at 3, 7, and 14 days following intracardiac administration of propofol had mild inflammatory changes, and no histopathologic lesions were seen 30 and 60 days following propofol administration. Intracardiac injection of propofol in snakes is safe and provides a rapid induction of anesthesia but leads to prolonged recovery, compared with that following induction with isoflurane. Histopathologic lesions in heart tissues following intracardiac injection of propofol were mild and resolved after 14 days.

  17. Anatomical evidence for intracardiac blood shunting in marine turtles

    African Journals Online (AJOL)

    Its presence suggests that right to left intra-cardiac blood shunts may be a feature of diving in sea turtles; the sphincter providing a mechanism for the control of blood flow through the heart. The comparative anatomy of the pulmonary arteries of selected terrestrial reptiles suggests that a similar mechanism exists in ...

  18. Anatomical Evidence for Intracardiac Blood Shunting in Marine Turtles

    African Journals Online (AJOL)

    ... suggests that right to left intra-cardiac blood shunts may be a feature of diving in sea turtles; the sphincter providing a mechanism for the control of blood flow through the heart. The comparative anatomy of the pulmonary arteries of selected terrestrial reptiles suggests that a similar mechanism exists in non-diving species.

  19. Early reperfusion hemodynamics predict recovery in rat hearts: a potential approach towards evaluating cardiac grafts from non-heart-beating donors.

    Directory of Open Access Journals (Sweden)

    Monika Dornbierer

    Full Text Available AIMS: Cardiac grafts from non-heartbeating donors (NHBDs could significantly increase organ availability and reduce waiting-list mortality. Reluctance to exploit hearts from NHBDs arises from obligatory delays in procurement leading to periods of warm ischemia and possible subsequent contractile dysfunction. Means for early prediction of graft suitability prior to transplantation are thus required for development of heart transplantation programs with NHBDs. METHODS AND RESULTS: Hearts (n = 31 isolated from male Wistar rats were perfused with modified Krebs-Henseleit buffer aerobically for 20 min, followed by global, no-flow ischemia (32°C for 30, 50, 55 or 60 min. Reperfusion was unloaded for 20 min, and then loaded, in working-mode, for 40 min. Left ventricular (LV pressure was monitored using a micro-tip pressure catheter introduced via the mitral valve. Several hemodynamic parameters measured during early, unloaded reperfusion correlated significantly with LV work after 60 min reperfusion (p<0.001. Coronary flow and the production of lactate and lactate dehydrogenase (LDH also correlated significantly with outcomes after 60 min reperfusion (p<0.05. Based on early reperfusion hemodynamic measures, a composite, weighted predictive parameter, incorporating heart rate (HR, developed pressure (DP and end-diastolic pressure, was generated and evaluated against the HR-DP product after 60 min of reperfusion. Effective discriminating ability for this novel parameter was observed for four HR*DP cut-off values, particularly for ≥20 *10(3 mmHg*beats*min(-1 (p<0.01. CONCLUSION: Upon reperfusion of a NHBD heart, early evaluation, at the time of organ procurement, of cardiac hemodynamic parameters, as well as easily accessible markers of metabolism and necrosis seem to accurately predict subsequent contractile recovery and could thus potentially be of use in guiding the decision of accepting the ischemic heart for transplantation.

  20. Relation between heart beat fluctuations and cyclic alternating pattern during sleep in insomnia patients.

    Science.gov (United States)

    de Leon-Lomeli, R; Murguia, J S; Chouvarda, I; Mendez, M O; Gonzalez-Galvan, E; Alba, A; Milioli, G; Grassi, A; Terzano, M G; Parrino, L

    2014-01-01

    Insomnia is a condition that affects the nervous and muscular system. Thirty percent of the population between 18 and 60 years suffers from insomnia. The effects of this disorder involve problems such as poor school or job performance and traffic accidents. In addition, patients with insomnia present changes in the cardiac function during sleep. Furthermore, the structure of electroencephalographic A-phases, which builds up the Cyclic Alternating Pattern during sleep, is related to the insomnia events. Therefore, the relationship between these brain activations (A-phases) and the autonomic nervous system would be of interest, revealing the interplay of central and autonomic activity during insomnia. With this goal, a study of the relationship between A-phases and heart rate fluctuations is presented. Polysomnography recording of five healthy subjects, five sleep misperception patients and five patients with psychophysiological insomnia were used in the study. Detrended Fluctuation Analysis (DFA) was used in order to evaluate the heart rate dynamics and this was correlated with the number of A-phases. The results suggest that pathological patients present changes in the dynamics of the heart rate. This is reflected in the modification of A-phases dynamics, which seems to modify of heart rate dynamics.

  1. Far beyond the Sun - I. The beating magnetic heart in Horologium

    Science.gov (United States)

    Alvarado-Gómez, Julián D.; Hussain, Gaitee A. J.; Drake, Jeremy J.; Donati, Jean-François; Sanz-Forcada, Jorge; Stelzer, Beate; Cohen, Ofer; Amazo-Gómez, Eliana M.; Grunhut, Jason H.; Garraffo, Cecilia; Moschou, Sofia P.; Silvester, James; Oksala, Mary E.

    2018-02-01

    A former member of the Hyades cluster, ι Horologii (ι Hor) is a planet-hosting Sun-like star which displays the shortest coronal activity cycle known to date (Pcyc ∼ 1.6 yr). With an age of ∼625 Myr, ι Hor is also the youngest star with a detected activity cycle. The study of its magnetic properties holds the potential to provide fundamental information to understand the origin of cyclic activity and stellar magnetism in late-type stars. In this series of papers, we present the results of a comprehensive project aimed at studying the evolving magnetic field in this star and how this evolution influences its circumstellar environment. This paper summarizes the first stage of this investigation, with results from a long-term observing campaign of ι Hor using ground-based high-resolution spectropolarimetry. The analysis includes precise measurements of the magnetic activity and radial velocity of the star, and their multiple time-scales of variability. In combination with values reported in the literature, we show that the long-term chromospheric activity evolution of ι Hor follows a beating pattern, caused by the superposition of two periodic signals of similar amplitude at P1 ≃ 1.97 ± 0.02 yr and P2 ≃ 1.41 ± 0.01 yr. Additionally, using the most recent parameters for ι Hor b in combination with our activity and radial velocity measurements, we find that stellar activity dominates the radial velocity residuals, making the detection of additional planets in this system challenging. Finally, we report here the first measurements of the surface longitudinal magnetic field strength of ι Hor, which displays varying amplitudes within ±4 G and served to estimate the rotation period of the star (P_rot = 7.70^{+0.18}_{-0.67} d).

  2. Clinical implications of hypothermic ventricular fibrillation versus beating-heart technique during cardiopulmonary bypass for pulmonary valve replacement in patients with repaired tetralogy of Fallot.

    Science.gov (United States)

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

    2017-09-01

    This study aimed to compare the effects of hypothermic ventricular fibrillation and beating-heart techniques during cardiopulmonary bypass (CPB) on postoperative outcomes after simple pulmonary valve replacement in patients with repaired tetralogy of Fallot (TOF). We retrospectively reviewed the data of 47 patients with repaired tetralogy of Fallot at a single institution, who received pulmonary valve replacement under the ventricular fibrillation or beating-heart technique without cardioplegic cardiac arrest during CPB between January 2005 and April 2015. The patients were divided into fibrillation (n = 32) and beating-heart (n = 15) groups. On comparing these groups, the fibrillation group had a larger sinotubular junction (27.1 ± 4.6 vs 22.1 ± 2.4 mm), had a longer operation duration (396 ± 108 vs 345 ± 57 min), required more postoperative transfusions (2.1 ± 2.6 vs 5.0 ± 6.3 units) and had a higher vasoactive-inotropic score at intensive care unit admission (8.0 vs 10, all P tetralogy of Fallot. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  3. Assessment of intracardiac flow and vorticity in the right heart of patients after repair of tetralogy of Fallot by flow-sensitive 4D MRI.

    Science.gov (United States)

    Hirtler, Daniel; Garcia, Julio; Barker, Alex J; Geiger, Julia

    2016-10-01

    To comprehensively and quantitatively analyse flow and vorticity in the right heart of patients after repair of tetralogy of Fallot (rTOF) compared with healthy volunteers. Time-resolved flow-sensitive 4D MRI was acquired in 24 rTOF patients and 12 volunteers. Qualitative flow evaluation was based on consensus reading of two observers. Quantitative analysis included segmentation of the right atrium (RA) and ventricle (RV) in a four-chamber view to extract volumes and regional haemodynamic information for computation of regional mean and peak vorticity. Right heart intra-atrial, intraventricular and outflow tract flow patterns differed considerably between rTOF patients and volunteers. Peak RA and mean RV vorticity was significantly higher in patients (p = 0.02/0.05). Significant negative correlations were found between patients' maximum and mean RV and RA vorticity and ventricular volumes (p tetralogy of Fallot. • Regurgitant flow in the main pulmonary artery is associated with higher right heart vorticity.

  4. Effectiveness of Remote Patient Monitoring After Discharge of Hospitalized Patients With Heart Failure: The Better Effectiveness After Transition–Heart Failure (BEAT-HF) Randomized Clinical Trial

    Science.gov (United States)

    Ong, Michael K.; Romano, Patrick S.; Edgington, Sarah; Aronow, Harriet U.; Auerbach, Andrew D.; Black, Jeanne T.; De Marco, Teresa; Escarce, Jose J.; Evangelista, Lorraine S.; Hanna, Barbara; Ganiats, Theodore G.; Greenberg, Barry H.; Greenfield, Sheldon; Kaplan, Sherrie H.; Kimchi, Asher; Liu, Honghu; Lombardo, Dawn; Mangione, Carol M.; Sadeghi, Bahman; Sadeghi, Banafsheh; Sarrafzadeh, Majid; Tong, Kathleen; Fonarow, Gregg C.

    2016-01-01

    Importance It remains unclear whether telemonitoring approaches provide benefits for patients with heart failure (HF) after hospitalization. Objective To evaluate the effectiveness of a care transition intervention using remote patient monitoring in reducing 180-day all-cause readmissions among a broad population of older adults hospitalized with HF. Design, Setting, and Participants We randomized 1437 patients hospitalized for HF between October 12, 2011, and September 30, 2013, to the intervention arm (715 patients) or to the usual care arm (722 patients) of the Better Effectiveness After Transition–Heart Failure (BEAT-HF) study and observed them for 180 days. The dates of our study analysis were March 30, 2014, to October 1, 2015. The setting was 6 academic medical centers in California. Participants were hospitalized individuals 50 years or older who received active treatment for decompensated HF. Interventions The intervention combined health coaching telephone calls and telemonitoring. Telemonitoring used electronic equipment that collected daily information about blood pressure, heart rate, symptoms, and weight. Centralized registered nurses conducted telemonitoring reviews, protocolized actions, and telephone calls. Main outcomes and measures The primary outcome was readmission for any cause within 180 days after discharge. Secondary outcomes were all-cause readmission within 30 days, all-cause mortality at 30 and 180 days, and quality of life at 30 and 180 days. Results Among 1437 participants, the median age was 73 years. Overall, 46.2% (664 of 1437) were female, and 22.0% (316 of 1437) were African American. The intervention and usual care groups did not differ significantly in readmissions for any cause 180 days after discharge, which occurred in 50.8% (363 of 715) and 49.2% (355 of 722) of patients, respectively (adjusted hazard ratio, 1.03; 95% CI, 0.88-1.20; P = .74). In secondary analyses, there were no significant differences in 30-day

  5. Auxotonic to isometric contraction transitioning in a beating heart causes myosin step-size to down shift.

    Directory of Open Access Journals (Sweden)

    Thomas P Burghardt

    Full Text Available Myosin motors in cardiac ventriculum convert ATP free energy to the work of moving blood volume under pressure. The actin bound motor cyclically rotates its lever-arm/light-chain complex linking motor generated torque to the myosin filament backbone and translating actin against resisting force. Previous research showed that the unloaded in vitro motor is described with high precision by single molecule mechanical characteristics including unitary step-sizes of approximately 3, 5, and 8 nm and their relative step-frequencies of approximately 13, 50, and 37%. The 3 and 8 nm unitary step-sizes are dependent on myosin essential light chain (ELC N-terminus actin binding. Step-size and step-frequency quantitation specifies in vitro motor function including duty-ratio, power, and strain sensitivity metrics. In vivo, motors integrated into the muscle sarcomere form the more complex and hierarchically functioning muscle machine. The goal of the research reported here is to measure single myosin step-size and step-frequency in vivo to assess how tissue integration impacts motor function. A photoactivatable GFP tags the ventriculum myosin lever-arm/light-chain complex in the beating heart of a live zebrafish embryo. Detected single GFP emission reports time-resolved myosin lever-arm orientation interpreted as step-size and step-frequency providing single myosin mechanical characteristics over the active cycle. Following step-frequency of cardiac ventriculum myosin transitioning from low to high force in relaxed to auxotonic to isometric contraction phases indicates that the imposition of resisting force during contraction causes the motor to down-shift to the 3 nm step-size accounting for >80% of all the steps in the near-isometric phase. At peak force, the ATP initiated actomyosin dissociation is the predominant strain inhibited transition in the native myosin contraction cycle. The proposed model for motor down-shifting and strain sensing involves ELC N

  6. Beating-Heart Versus Conventional On-Pump Coronary Artery Bypass Grafting: A Meta-Analysis of Clinical Outcomes.

    Science.gov (United States)

    Chaudhry, Umar A R; Harling, Leanne; Sepehripour, Amir H; Stavridis, George; Kokotsakis, John; Ashrafian, Hutan; Athanasiou, Thanos

    2015-12-01

    Beating-heart on-pump coronary artery bypass grafting (BH-ONCAB) offers a hybrid coronary revascularization technique that may confer the benefits of an "off-pump" operation while maintaining the hemodynamic stability and mechanical support of conventional on-pump CABG (C-ONCAB). This study aimed to identify whether BH-ONCAB confers a morbidity or mortality benefit over C-ONCAB in the immediate and midterm postoperative period. A systematic literature review identified 13 studies incorporating 3,930 patients (937 BH-ONCAB; 2,993 C-ONCAB) fulfilling our inclusion criteria. Outcomes were meta-analyzed using random-effects modelling. Between-study heterogeneity was investigated through quality assessment, subgroup, and risk of bias analysis. No difference was seen in overall 30-day mortality (13 studies; odds ratio, 0.60; 95% confidence interval, 0.32 to 1.14; p = 0.12), or midterm survival (5 studies; hazard ratio, 0.65; 95% confidence interval, 0.22 to 1.88; p = 0.43) between BH-ONCAB and C-ONCAB. BH-ONCAB was associated with significantly fewer postoperative myocardial infarction events (odds ratio, 0.32; 95% confidence interval, 0.11 to 0.92; p = 0.03); however, no significant difference was observed in other postoperative morbidity outcomes. Intraoperatively, BH-ONCAB resulted in significantly less intraaortic balloon pump use, shorter cardiopulmonary bypass time, and less blood loss. The number of anastomoses and vessels grafted were not significantly different between BH-ONCAB and C-ONCAB. BH-ONCAB is a safe and comparable alternative to C-ONCAB in terms of early mortality and late survival. Furthermore, BH-ONCAB may confer a particular advantage in preventing perioperative myocardial infarction and reducing overall blood loss. Future work should focus on larger matched studies and multicenter randomized controlled trials that risk-stratify patients according to preoperative ventricular function and renal insufficiency to allow us to optimize our surgical

  7. Is High Temporal Resolution Achievable for Paediatric Cardiac Acquisitions during Several Heart Beats? Illustration with Cardiac Phase Contrast Cine-MRI.

    Directory of Open Access Journals (Sweden)

    Laurent Bonnemains

    Full Text Available During paediatric cardiac Cine-MRI, data acquired during cycles of different lengths must be combined. Most of the time, Feinstein's model is used to project multiple cardiac cycles of variable lengths into a mean cycle.To assess the effect of Feinstein projection on temporal resolution of Cine-MRI.1/The temporal errors during Feinstein's projection were computed in 306 cardiac cycles fully characterized by tissue Doppler imaging with 6-phase analysis (from a population of 7 children and young adults. 2/The effects of these temporal errors on tissue velocities were assessed by simulating typical tissue phase mapping acquisitions and reconstructions. 3/Myocardial velocities curves, extracted from high-resolution phase-contrast cine images, were compared for the 6 volunteers with lowest and highest heart rate variability, within a population of 36 young adults.1/The mean of temporal misalignments was 30 ms over the cardiac cycle but reached 60 ms during early diastole. 2/During phase contrast MRI simulation, early diastole velocity peaks were diminished by 6.1 cm/s leading to virtual disappearance of isovolumic relaxation peaks. 3/The smoothing and erasing of isovolumic relaxation peaks was confirmed on tissue phase mapping velocity curves, between subjects with low and high heart rate variability (p = 0.05.Feinstein cardiac model creates temporal misalignments that impair high temporal resolution phase contrast cine imaging when beat-to-beat heart rate is changing.

  8. Is High Temporal Resolution Achievable for Paediatric Cardiac Acquisitions during Several Heart Beats? Illustration with Cardiac Phase Contrast Cine-MRI.

    Science.gov (United States)

    Bonnemains, Laurent; Odille, Freddy; Meyer, Christophe; Hossu, Gabriella; Felblinger, Jacques; Vuissoz, Pierre-André

    2015-01-01

    During paediatric cardiac Cine-MRI, data acquired during cycles of different lengths must be combined. Most of the time, Feinstein's model is used to project multiple cardiac cycles of variable lengths into a mean cycle. To assess the effect of Feinstein projection on temporal resolution of Cine-MRI. 1/The temporal errors during Feinstein's projection were computed in 306 cardiac cycles fully characterized by tissue Doppler imaging with 6-phase analysis (from a population of 7 children and young adults). 2/The effects of these temporal errors on tissue velocities were assessed by simulating typical tissue phase mapping acquisitions and reconstructions. 3/Myocardial velocities curves, extracted from high-resolution phase-contrast cine images, were compared for the 6 volunteers with lowest and highest heart rate variability, within a population of 36 young adults. 1/The mean of temporal misalignments was 30 ms over the cardiac cycle but reached 60 ms during early diastole. 2/During phase contrast MRI simulation, early diastole velocity peaks were diminished by 6.1 cm/s leading to virtual disappearance of isovolumic relaxation peaks. 3/The smoothing and erasing of isovolumic relaxation peaks was confirmed on tissue phase mapping velocity curves, between subjects with low and high heart rate variability (p = 0.05). Feinstein cardiac model creates temporal misalignments that impair high temporal resolution phase contrast cine imaging when beat-to-beat heart rate is changing.

  9. ProSeal laryngeal mask airway as an alternative to standard endotracheal tube in securing upper airway in the patients undergoing beating-heart coronary artery bypass grafting

    Directory of Open Access Journals (Sweden)

    Kalpana Shah

    2017-01-01

    Full Text Available Background: ProSeal laryngeal mask airways (PLMAs are routinely used after failed tracheal intubation as airway rescue, facilitating tracheal intubation by acting as a conduit and to secure airway during emergencies. In long duration surgeries, use of endotracheal tube (ETT is associated with various hemodynamic complications, which are minimally affected during PLMA use. However, except for few studies, there are no significant data available that promote the use of laryngeal mask during cardiac surgery. This prospective study was conducted with the objective of demonstrating the advantages of PLMA over ETT in the patients undergoing beating-heart coronary artery bypass graft (CABG. Methodology: This prospective, interventional study was carried out in 200 patients who underwent beating-heart CABG. Patients were randomized in equal numbers to either ETT group or PLMA group, and various hemodynamic and respiratory parameters were observed at different time points. Results: Patients in PLMA group had mean systolic blood pressure 126.10 ± 5.31 mmHg compared to the patients of ETT group 143.75 ± 6.02 mmHg. Pulse rate in the PLMA group was less (74.52 ± 10.79 per min (P < 0.05 compared to ETT group (81.72 ± 9.8. Thus, hemodynamic changes were significantly lower (P < 0.05 in PLMA than in ETT group. Respiratory parameters such as oxygen saturation, pressure CO 2 (pCO 2 , peak airway pressure, and lung compliance were similar to ETT group at all evaluation times. The incidence of adverse events was also lower in PLMA group. Conclusion: In experience hand, PLMA offers advantages over the ETT in airway management in the patients undergoing beating-heart CABG.

  10. A Multidisciplinary Approach to Unplanned Conversion from Off-Pump to On-Pump Beating Heart Coronary Artery Revascularization in Patients with Compromised Left Ventricular Function

    Directory of Open Access Journals (Sweden)

    Georgia Tsaousi

    2014-01-01

    Full Text Available Aim. To comparably assess the perioperative risk factors that differentiate off-pump coronary artery bypass (OPCAB grafting cases from those sustaining unplanned conversion to on-pump beating heart (ONCAB/BH approach, in patients with left ventricular ejection fraction (LVEF 2 days (P=0.007. Conclusions. Patients with LVEF < 40% undergoing ONCAB/BH are subjected to more preoperative comorbidities and implicated ICU stay than their OPCAB counterparts, which influences adversely short-term morbidity, while operative mortality remains unaffected.

  11. Left Ventricular Assist Device Implantation After Intracardiac Parachute Device Removal.

    Science.gov (United States)

    Abu Saleh, Walid K; Al Jabbari, Odeaa; Bruckner, Brian A; Suarez, Erik E; Estep, Jerry D; Loebe, Matthias

    2015-08-01

    Left ventricular assist device implantation is a proven and efficient modality for the treatment of end-stage heart failure. Left ventricular assist device versatility as a bridge to heart transplantation or destination therapy has led to improved patient outcomes with a concomitant rise in its overall use. Other less invasive treatment modalities are being developed to improve heart function and morbidity and mortality for the heart failure population. Percutaneous ventricular restoration is a new investigational therapy that deploys an intracardiac parachute to wall off damaged myocardium in patients with dilated left ventricles and ischemic heart failure. Clinical trials are under way to test the efficacy of percutaneous ventricular restoration using the parachute device. This review describes our encounter with the parachute device, its explantation due to refractory heart failure, and surgical replacement with a left ventricular assist device. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  12. Gating planar 99m-Tc MIBI projections with MUGA protocol and beating heart mode assessment, for identifying hibernation - comparison with quantitative gated SPECT

    International Nuclear Information System (INIS)

    Petrovici, R.L.; Medrea, C.; Capalneanu, R.; Codorean, I.; Focea, I.

    2002-01-01

    Purpose: assessment of the utility of gating planar 99m-Tc MIBI projections with MUGA protocol, for identifying endsystolic thickening of a region with decreased uptake and wall motion abnormalities, as hibernating myocardium. Material and method: Group A - 53 p with LVEF 20%. Results: In group A, from 68 regions with present thickening on MUGA, 62 had improved uptake after revascularization (91%), from 39 without thickening, 4 had improvement (10%). In group B, from 16 regions with thickening on MUGA, 15 had thickening on the polar maps and 14 (88%) improved uptake; from 12 regions without thickening on MUGA, 2 had thickening on the polar maps and 1 (8%) had improvement. Correlation between improvement in uptake and increase > 5% in LVEF was very good (p < 0,05). Comparing wall motion on MUGA and QGS (surfaces, slices and polar maps), in the 110 regions, there was agreement in 98 (89%) regions. Conclusions: Highly efficient identification of hibernation is possible with planar gamma cameras, using MUGA for qualitative wall motion and ES thickening assessment on 'beating heart' mode. For fine-tuning or settlement of disagreement between uptake and ES thickening on gated - SPECT, planar 'beating heart' mode could help in the balance

  13. Effects of exogenous surfactant on the non-heart-beating donor lung graft in experimental lung transplantation – a stereological study

    Science.gov (United States)

    Herrmann, Gudrun; Knudsen, Lars; Madershahian, Navid; Mühlfeld, Christian; Frank, Konrad; Rahmanian, Parwis; Wahlers, Thorsten; Wittwer, Thorsten; Ochs, Matthias

    2014-01-01

    The use of non-heart-beating donor (NHBD) lungs may help to overcome the shortage of lung grafts in clinical lung transplantation, but warm ischaemia and ischaemia/reperfusion injury (I/R injury) resulting in primary graft dysfunction represent a considerable threat. Thus, better strategies for optimized preservation of lung grafts are urgently needed. Surfactant dysfunction has been shown to contribute to I/R injury, and surfactant replacement therapy is effective in enhancing lung function and structural integrity in related rat models. In the present study we hypothesize that surfactant replacement therapy reduces oedema formation in a pig model of NHBD lung transplantation. Oedema formation was quantified with (SF) and without (non-SF) surfactant replacement therapy in interstitial and alveolar compartments by means of design-based stereology in NHBD lungs 7 h after cardiac arrest, reperfusion and transplantation. A sham-operated group served as control. In both NHBD groups, nearly all animals died within the first hours after transplantation due to right heart failure. Both SF and non-SF developed an interstitial oedema of similar degree, as shown by an increase in septal wall volume and arithmetic mean thickness as well as an increase in the volume of peribron-chovascular connective tissue. Regarding intra-alveolar oedema, no statistically significant difference could be found between SF and non-SF. In conclusion, surfactant replacement therapy cannot prevent poor outcome after prolonged warm ischaemia of 7 h in this model. While the beneficial effects of surfactant replacement therapy have been observed in several experimental and clinical studies related to heart-beating donor lungs and cold ischaemia, it is unlikely that surfactant replacement therapy will overcome the shortage of organs in the context of prolonged warm ischaemia, for example, 7 h. Moreover, our data demonstrate that right heart function and dysfunctions of the pulmonary vascular bed

  14. Results of beating heart mitral valve surgery via the trans-septal approach Resultados da abordagem transeptal para a valva mitral com coração batendo

    Directory of Open Access Journals (Sweden)

    Tomas A Salerno

    2009-03-01

    Full Text Available OBJECTIVE: Mitral valve surgery can be performed through the trans-atrial or the trans-septal approach. Although the trans-atrial is the preferred method, the trans-septal approach has also been used recently and has a particular value in beating-heart mitral valve surgery. Herein we report our experience with beating-heart mitral valve surgery via trans-septal approach, and discuss its advantages and pitfalls. METHODS: Between 2000 and 2007, 214 consecutive patients were operated upon utilizing beating heart technique for mitral valve surgery. The operation was performed via transseptal approach with the aorta unclamped, the heart beating, with normal electrocardiogram and in sinus rhythm. RESULTS: Mean age was 56.03 ± 13.93 years (range: 19-86 years; median: 56 years. There were 131 (61.2% males and 83 (38.8% females. Of the prostheses used, 108 (50.5% were biological, and 39 (18.2% were mechanical. Mitral repairs were performed in 67 (31.3% patients. Mean hospital stay was 17.4 ± 20.0 days (range: 3-135 days; median: 11 days. Intra-aortic balloon pump (IABP utilization was required in 12 (5.6% of 214 patients. One-month mortality was 7.4%, and re-operation for bleeding was needed in 15 (7% patients. CONCLUSIONS: Beating-heart mitral valve surgery is an option for myocardial protection in patients undergoing mitral valve surgery. This technique is facilitated by the trans-septal approach due to reduced aortic insufficiency and improved visualization of the mitral apparatus.OBJETIVO: A cirurgia da valva mitral pode ser feita via transatrial ou transeptal. Embora a transatrial seja a preferida, a via transeptal tem sido utilizada mais recentemente e tido um grande valor nas operações com o coração batendo. Mostramos a nossa experiência na cirurgia da valva mitral via transeptal com coração batendo e discutimos seus benefícios e problemas. MÉTODOS: Entre 2000 e 2007, 214 pacientes consecutivos foram operados com o coração batendo. A

  15. Forward-looking intracardiac ultrasound imaging using a 1-D CMUT array integrated with custom front-end electronics.

    Science.gov (United States)

    Nikoozadeh, Amin; Wygant, Ira O; Lin, Der-Song; Oralkan, Omer; Ergun, A Sanli; Stephens, Douglas N; Thomenius, Kai E; Dentinger, Aaron M; Wildes, Douglas; Akopyan, Gina; Shivkumar, Kalyanam; Mahajan, Aman; Sahn, David J; Khuri-Yakub, Butrus T

    2008-12-01

    Minimally invasive catheter-based electrophysiological (EP) interventions are becoming a standard procedure in diagnosis and treatment of cardiac arrhythmias. As a result of technological advances that enable small feature sizes and a high level of integration, nonfluoroscopic intracardiac echocardiography (ICE) imaging catheters are attracting increasing attention. ICE catheters improve EP procedural guidance while reducing the undesirable use of fluoroscopy, which is currently the common catheter guidance method. Phased-array ICE catheters have been in use for several years now, although only for side-looking imaging. We are developing a forward-looking ICE catheter for improved visualization. In this effort, we fabricate a 24-element, fine-pitch 1-D array of capacitive micromachined ultrasonic transducers (CMUT), with a total footprint of 1.73 mm x 1.27 mm. We also design a custom integrated circuit (IC) composed of 24 identical blocks of transmit/ receive circuitry, measuring 2.1 mm x 2.1 mm. The transmit circuitry is capable of delivering 25-V unipolar pulses, and the receive circuitry includes a transimpedance preamplifier followed by an output buffer. The CMUT array and the custom IC are designed to be mounted at the tip of a 10-Fr catheter for high-frame-rate forward-looking intracardiac imaging. Through-wafer vias incorporated in the CMUT array provide access to individual array elements from the back side of the array. We successfully flip-chip bond a CMUT array to the custom IC with 100% yield. We coat the device with a layer of polydimethylsiloxane (PDMS) to electrically isolate the device for imaging in water and tissue. The pulse-echo in water from a total plane reflector has a center frequency of 9.2 MHz with a 96% fractional bandwidth. Finally, we demonstrate the imaging capability of the integrated device on commercial phantoms and on a beating ex vivo rabbit heart (Langendorff model) using a commercial ultrasound imaging system.

  16. Induction of chagasic-like arrhythmias in the isolated beating hearts of healthy rats perfused with Trypanosoma cruzi-conditioned medium

    Directory of Open Access Journals (Sweden)

    H. Rodriguez-Angulo

    2013-01-01

    Full Text Available Chagas' myocardiopathy, caused by the intracellular protozoan Trypanosoma cruzi, is characterized by microvascular alterations, heart failure and arrhythmias. Ischemia and arrythmogenesis have been attributed to proteins shed by the parasite, although this has not been fully demonstrated. The aim of the present investigation was to study the effect of substances shed by T. cruzi on ischemia/reperfusion-induced arrhythmias. We performed a triple ischemia-reperfusion (I/R protocol whereby the isolated beating rat hearts were perfused with either Vero-control or Vero T. cruzi-infected conditioned medium during the different stages of ischemia and subsequently reperfused with Tyrode's solution. ECG and heart rate were recorded during the entire experiment. We observed that triple I/R-induced bradycardia was associated with the generation of auricular-ventricular blockade during ischemia and non-sustained nodal and ventricular tachycardia during reperfusion. Interestingly, perfusion with Vero-infected medium produced a delay in the reperfusion-induced recovery of heart rate, increased the frequency of tachycardic events and induced ventricular fibrillation. These results suggest that the presence of parasite-shed substances in conditioned media enhances the arrhythmogenic effects that occur during the I/R protocol.

  17. Efficacy of the direct myocardial revascularization performed on the beating heart or performed with the use of extra corporal circulation - comparison by means of myocardial perfusion SPECT

    International Nuclear Information System (INIS)

    Kwinecki, P.; Jemielity, M.; Dyszkiewicz, W.; Czepczynski, R.; Sowinski, J.

    2002-01-01

    Introduction. In the recent years, new techniques of direct myocardial revascularization: OPCAB - off pump coronary artery bypass and MIDCAB - minimal invasive coronary artery bypass were developed. Aim of this study was to compare the efficacy of these methods with that of CABG performed with the use of extracorporal circulation. Material and methods. 20 patients operated on the beating heart (group 1; 16 men and 4 women; aged 40 to 65 years; mean 53,0 ±8,6 years) and 36 patients operated in the extracorporal circulation (group 2; 33 men and 3 women; aged 34 to 69 years, mean 52,5 ±8,6 years). In all the patients myocardial SPECT using 99mTc-MIBI at rest and after stimulation with dipyridamole (0,56 mg/kg) was performed twice: before and 4-7 months after revascularization. Myocardial perfusion was evaluated in 9 segments using following scale: from 1 (normal) to 5 points (no uptake). The average score in all nine segments constituted a perfusion index (PI). The differences of PI before and after operation, both at rest and after dipyridamole were compared. Results. In none of the patients of group 1 a perioperational ischemia was found by ECG or enzymatic (CK-MB) measurements. In a part of group 2 signs of transient ischemia were found. Global evaluation of perfusion in SPECT is presented. PI were similar in both groups, both at rest and after dipyridamole. Conclusion: Efficacy of the direct myocardial revascularization performed on the beating heart is similar to that of the CABG operations performed with the use of extracorporal circulation. The OPCAB and MIDCAM operations are less traumatizing

  18. Ex vivo rehabilitation of non-heart-beating donor lungs in preclinical porcine model: delayed perfusion results in superior lung function.

    Science.gov (United States)

    Mulloy, Daniel P; Stone, Matthew L; Crosby, Ivan K; Lapar, Damien J; Sharma, Ashish K; Webb, David V; Lau, Christine L; Laubach, Victor E; Kron, Irving L

    2012-11-01

    Ex vivo lung perfusion (EVLP) is a promising modality for the evaluation and treatment of marginal donor lungs. The optimal timing of EVLP initiation and the potential for rehabilitation of donor lungs with extended warm ischemic times is unknown. The present study compared the efficacy of different treatment strategies for uncontrolled non-heart-beating donor lungs. Mature swine underwent hypoxic arrest, followed by 60 minutes of no-touch warm ischemia. The lungs were harvested and flushed with 4°C Perfadex. Three groups (n = 5/group) were stratified according to the preservation method: cold static preservation (CSP; 4 hours of 4°C storage), immediate EVLP (I-EVLP: 4 hours EVLP at 37°C), and delayed EVLP (D-EVLP; 4 hours of CSP followed by 4 hours of EVLP). The EVLP groups were perfused with Steen solution supplemented with heparin, methylprednisolone, cefazolin, and an adenosine 2A receptor agonist. The lungs then underwent allotransplantation and 4 hours of recipient reperfusion before allograft assessment for resultant ischemia-reperfusion injury. The donor blood oxygenation (partial pressure of oxygen/fraction of inspired oxygen ratio) before death was not different between the groups. The oxygenation after transplantation was significantly greater in the D-EVLP group than in the I-EVLP or CSP groups. The mean airway pressure, pulmonary artery pressure, and expression of interleukin-8, interleukin-1β, and tumor necrosis factor-α were all significantly reduced in the D-EVLP group. Post-transplant oxygenation exceeded the acceptable clinical levels only in the D-EVLP group. Uncontrolled non-heart-beating donor lungs with extended warm ischemia can be reconditioned for successful transplantation. The combination of CSP and EVLP in the D-EVLP group was necessary to obtain optimal post-transplant function. This finding, if confirmed clinically, will allow expanded use of nonheart-beating donor lungs. Copyright © 2012 The American Association for Thoracic

  19. Beat to beat variability in cardiovascular variables: noise or music?

    Science.gov (United States)

    Appel, M. L.; Berger, R. D.; Saul, J. P.; Smith, J. M.; Cohen, R. J.

    1989-01-01

    Cardiovascular variables such as heart rate, arterial blood pressure, stroke volume and the shape of electrocardiographic complexes all fluctuate on a beat to beat basis. These fluctuations have traditionally been ignored or, at best, treated as noise to be averaged out. The variability in cardiovascular signals reflects the homeodynamic interplay between perturbations to cardiovascular function and the dynamic response of the cardiovascular regulatory systems. Modern signal processing techniques provide a means of analyzing beat to beat fluctuations in cardiovascular signals, so as to permit a quantitative, noninvasive or minimally invasive method of assessing closed loop hemodynamic regulation and cardiac electrical stability. This method promises to provide a new approach to the clinical diagnosis and management of alterations in cardiovascular regulation and stability.

  20. Beat Dreams?

    DEFF Research Database (Denmark)

    Sørensen, Bent

    2009-01-01

    Two of the founding members of the Beat Generation of the 1950s wrote dream books with almost identical titles: Jack Kerouac's Book of Dreams (1961) and William Burroughs' My Education: A Book of Dreams (1995). This paper queries the function of such dream books, both from a perspective of seeing...... dream writing as a confessional genre, and from the perspective of didacticism implicit in sharing one's dream life with one's readers. What role does memory, politics, fantasies and reality play in communicating with and via dreams?...

  1. Aneurismectomia de ventrículo esquerdo com o coração batendo ininterruptamente: resultados imediatos Left ventricular aneurysmectomy with continuous beating heart: early results

    Directory of Open Access Journals (Sweden)

    Valquíria Pelisser Campagnucci

    2006-03-01

    Full Text Available OBJETIVO: O índice médio de mortalidade operatória na aneurismectomia de ventrículo esquerdo é de 15%. Formas de proteção miocárdica especificamente para este procedimento têm sido pouco discutidas. Este trabalho tem por finalidade a avaliação dos resultados imediatos do tratamento cirúrgico do aneurisma da parede anterior de ventrículo esquerdo, sob circulação extracorpórea, com o coração batendo ininterruptamente. MÉTODO: Análise retrospectiva de 34 prontuários de pacientes submetidos a aneurismectomia anterior, associada ou não à revascularização do miocárdio, no período de janeiro de 1997 a maio de 2005. Foram avaliados 20 doentes do sexo masculino e 14 do sexo feminino, com média de idade de 52 anos (28 a 76 anos. Todos os pacientes foram operados sob circulação extracorpórea em normotermia, sem pinçamento aórtico, mantendo-se o coração batendo o tempo todo. Foram analisados: mortalidade perioperatória, complicações tromboembólicas, tempo de circulação extracorpórea, tempo de assistência ventilatória invasiva e permanência na Unidade de Terapia Intensiva (UTI. RESULTADOS: Não houve mortalidade perioperatória. Não observamos complicações tromboembólicas. O tempo de circulação extracorpórea foi, em média, de 85min (25-150min. O tempo de assistência ventilatória invasiva foi, em média, de 18h (8-96h e de permanência na UTI, 3,1 dias (2- 14 dias. CONCLUSÃO: A manutenção dos batimentos cardíacos pela tática de não pinçamento aórtico para proteção miocárdica constitui-se num método eficiente e seguro para aneurismectomia de parede anterior de ventrículo esquerdo.OBJECTIVE: Operative mortality after left ventricular aneurysmectomy is close to 15%. Specifically for this procedure, forms of myocardial protection have been little discussed. The purpose of this study was to evaluate immediate results of left anterior ventricular aneurysmectomy using the beating heart approach

  2. Volumetric Single-Beat Coronary Computed Tomography Angiography: Relationship of Image Quality, Heart Rate, and Body Mass Index. Initial Patient Experience With a New Computed Tomography Scanner.

    Science.gov (United States)

    Latif, Muhammad Aamir; Sanchez, Frank W; Sayegh, Karl; Veledar, Emir; Aziz, Muhammad; Malik, Rehan; Haider, Imran; Agatston, Arthur S; Batlle, Juan C; Janowitz, Warren; Peña, Constantino; Ziffer, Jack A; Nasir, Khurram; Cury, Ricardo C

    2016-01-01

    Cardiac computed tomography (CT) image quality (IQ) is very important for accurate diagnosis. We propose to evaluate IQ expressed as Likert scale, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) from coronary CT angiography images acquired with a new volumetric single-beat CT scanner on consecutive patients and assess the IQ dependence on heart rate (HR) and body mass index (BMI). We retrospectively analyzed the data of the first 439 consecutive patients (mean age, 55.13 [SD, 12.1] years; 51.47% male), who underwent noninvasive coronary CT angiography in a new single-beat volumetric CT scanner (Revolution CT) to evaluate chest pain at West Kendall Baptist Hospital. Based on patient BMI (mean, 29.43 [SD, 5.81] kg/m), the kVp (kilovolt potential) value and tube current were adjusted within a range of 80 to 140 kVp and 122 to 720 mA, respectively. Each scan was performed in a single-beat acquisition within 1 cardiac cycle, regardless of the HR. Motion correction software (SnapShot Freeze) was used for correcting motion artifacts in patients with higher HRs. Autogating was used to automatically acquire systolic and diastolic phases for higher HRs with electrocardiographic milliampere dose modulation. Image quality was assessed qualitatively by Likert scale and quantitatively by SNR and CNR for the 4 major vessels right coronary, left main, left anterior descending, and left circumflex arteries on axial and multiplanar reformatted images. Values for Likert scale were as follows: 1, nondiagnostic; 2, poor; 3, good; 4, very good; and 5, excellent. Signal-to-noise ratio and CNR were calculated from the average 2 CT attenuation values within regions of interest placed in the proximal left main and proximal right coronary artery. For contrast comparison, a region of interest was selected from left ventricular wall at midcavity level using a dedicated workstation. We divided patients in 2 groups related to the HR: less than or equal to 70 beats/min (bpm) and

  3. Beating Depression …Help Is Available

    Science.gov (United States)

    ... Navigation Bar Home Current Issue Past Issues Beating Depression …Help Is Available Past Issues / Summer 2007 Table ... treatments are available from your physician. Types of Depression Just like other illnesses, such as heart disease, ...

  4. A new preservation solution (SCOT 15) Improves the islet isolation process from pancreata of non-heart-beating donors: a Murine model.

    Science.gov (United States)

    Giraud, S; Hauet, T; Eugene, M; Mauco, G; Barrou, B

    2009-10-01

    Due to the organ shortage, there is increased use of organs harvested from non-heart-beating donors (NHBD). These organs have been subjected to a period of warm ischemia that is most deleterious to functional recovery. We have designed a new preservation solution, "Solution de Conservation des Organes et des Tissus" (SCOT 15; Macopharma, Tourcoing, France) which contains an extracellular ionic composition including PEG 20 kD (15 g/L) as a colloid. Our objective was to compare SCOT 15 with University of Wisconsin (UW) solution or islet culture medium CMRL 1066 + 1% of Bovine Serum Albumin (BSA), as the working and preservation solution for islet isolation from pancreata subjected to warm ischemia using a murine model. Warm ischemia decreased the islet yield and cellular viability regardless of the preservation solution. Either when the pancreas was or was not subjected to warm ischemia, the best islet yield was obtained with SCOT 15 (P < .05 vs UW or CMRL 1066). The same results were observed for islet viability as assessed using the 3,(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) test; namely, better viability with SCOT 15 as compared with UW or CMRL 1066 (P < .01). In a murine model SCOT 15 was a better preservation solution for islet isolation than UW solution or culture medium (CMRL 1066).

  5. Scaling analysis of heart beat fluctuations data and its relationship with cyclic alternating pattern data during sleep

    Science.gov (United States)

    de León-Lomelí, R.; Murguía, J. S.; Chouvarda, I.; Méndez, M. O.; González-Galván, E.; Alba, A.

    2016-01-01

    During sleep there exists a nonlinear dynamic phenomenon, which is called cyclic alternating pattern. This phenomenon is generated in the brain and is composed of a series of events of short duration known as A-phases. It has been shown that A-phases can be found in other physiological systems such as the cardiovascular. However, there is no evidence that shows the temporal influence of the A-phases with the cardiovascular system. For this purpose, we consider the scaling method known as detrended fluctuation analysis (DFA). The analysis was carried out in well sleepers and insomnia people, and the numerical results show an increment in the scaling parameter for the insomnia subjects compared with the normal ones. In addition, the results of the heart dynamics suggests a persistent behavior toward the 1/f-noise.

  6. A Leadless Intracardiac Transcatheter Pacing System

    NARCIS (Netherlands)

    Reynolds, Dwight; Duray, Gabor Z.; Omar, Razali; Soejima, Kyoko; Neuzil, Petr; Zhang, Shu; Narasimhan, Calambur; Steinwender, Clemens; Brugada, Josep; Lloyd, Michael; Roberts, Paul R.; Sagi, Venkata; Hummel, John; Bongiorni, Maria Grazia; Knops, Reinoud E.; Ellis, Christopher R.; Gornick, Charles C.; Bernabei, Matthew A.; Laager, Verla; Stromberg, Kurt; Williams, Eric R.; Hudnall, J. Harrison; Ritter, Philippe; Duray, Gabor Zoltan; Roberts, Paul; Gornick, Charles; Ellis, Christopher; Gonzalez, Efrain; Boersma, Lucas V. A.; Chinitz, Larry; Bernabei, Matthew; Shinn, Timothy; Jones, Randy; Schoenhard, John; Kusano, Kengo; Philippon, Francois; Atwater, Brett; Voigt, Andrew; Asano, Taku; Kowal, Robert; Simmers, Timothy Alexander; Milasinovic, Goran; Bahl, Vinay Kumar; Seger, John; Shehata, Michael; Thibault, Bernard T.; Ishikawa, Toshiyuki; Sra, Jasbir; Giocondo, Michael; Johnson, Eric; Wilkoff, Bruce; Collier, Jack; Hill, John; Vardas, Panos E.; Mittal, Suneet; Grubman, Eric; Ferguson, John; Svendsen, Jesper Hastrup; Chin, Ashley; Rogers, John; Jadonath, Ram; Tyagi, Sanjay; Ghali, Magdi; Coyne, Robert; Esberg, Douglas; Duray, Gabor

    2016-01-01

    A leadless intracardiac transcatheter pacing system has been designed to avoid the need for a pacemaker pocket and transvenous lead. In a prospective multicenter study without controls, a transcatheter pacemaker was implanted in patients who had guideline-based indications for ventricular pacing.

  7. Intracardiac and intracerebral thrombosis associated with ...

    African Journals Online (AJOL)

    Thromboembolic complications are a significant cause of morbidity and mortality in cases of nephrotic syndrome. Hereditary thrombophilias are also known to increase vascular thrombosis. We present a case that has been followed up for steroid-resistant nephrotic syndrome (NS) in which intracardiac and intracranial ...

  8. Heart beats in the cloud: distributed analysis of electrophysiological 'Big Data' using cloud computing for epilepsy clinical research.

    Science.gov (United States)

    Sahoo, Satya S; Jayapandian, Catherine; Garg, Gaurav; Kaffashi, Farhad; Chung, Stephanie; Bozorgi, Alireza; Chen, Chien-Hun; Loparo, Kenneth; Lhatoo, Samden D; Zhang, Guo-Qiang

    2014-01-01

    The rapidly growing volume of multimodal electrophysiological signal data is playing a critical role in patient care and clinical research across multiple disease domains, such as epilepsy and sleep medicine. To facilitate secondary use of these data, there is an urgent need to develop novel algorithms and informatics approaches using new cloud computing technologies as well as ontologies for collaborative multicenter studies. We present the Cloudwave platform, which (a) defines parallelized algorithms for computing cardiac measures using the MapReduce parallel programming framework, (b) supports real-time interaction with large volumes of electrophysiological signals, and (c) features signal visualization and querying functionalities using an ontology-driven web-based interface. Cloudwave is currently used in the multicenter National Institute of Neurological Diseases and Stroke (NINDS)-funded Prevention and Risk Identification of SUDEP (sudden unexplained death in epilepsy) Mortality (PRISM) project to identify risk factors for sudden death in epilepsy. Comparative evaluations of Cloudwave with traditional desktop approaches to compute cardiac measures (eg, QRS complexes, RR intervals, and instantaneous heart rate) on epilepsy patient data show one order of magnitude improvement for single-channel ECG data and 20 times improvement for four-channel ECG data. This enables Cloudwave to support real-time user interaction with signal data, which is semantically annotated with a novel epilepsy and seizure ontology. Data privacy is a critical issue in using cloud infrastructure, and cloud platforms, such as Amazon Web Services, offer features to support Health Insurance Portability and Accountability Act standards. The Cloudwave platform is a new approach to leverage of large-scale electrophysiological data for advancing multicenter clinical research.

  9. Associations of BMI and its fat-free and fat components with blood lipids in children: Project HeartBeat!

    Science.gov (United States)

    Dai, Shifan; Eissa, Mona A; Steffen, Lyn M; Fulton, Janet E; Harrist, Ronald B; Labarthe, Darwin R

    2011-04-01

    AIM: This study aimed to distinguish between the roles of the two components of BMI, the fat mass (FM) index and the fat-free mass (FFM) index, in BMI's association with blood lipids in children and adolescents. METHODS: A total of 678 children (49.1% female, 79.9% non-black), initially aged 8, 11 and 14 years, were followed at 4-month intervals for up to 4 years (1991-1995). Total cholesterol (TC), LDL-C, HDL-C and triglycerides were determined in fasting blood samples. FFM index and FM index were calculated as FFM (kg)/height (m)(2) and FM (kg)/height (m)(2), respectively. Using a multilevel linear model, repeated measurements of blood lipids were regressed on concurrent measures of BMI or its components, adjusting for age, sex and race and, in a subsample, also for physical activity, energy intake and sexual maturity. RESULTS: Estimated regression coefficients for the relations of TC with BMI, FFM index and FM index were 1.539, -0.606 (p > 0.05) and 3.649, respectively. When FFM index and FM index were entered into the TC model simultaneously, regression coefficients were -0.855 and 3.743, respectively. An increase in BMI was related to an increase in TC; however, an equivalent increase in FM index was related to a greater increase in TC and, when FFM index was tested alone or with FM index, an increase in FFM index was related to a decrease in TC. Similar results were observed for LDL-C. FFM index and FM index were both inversely related to HDL-C and directly to triglycerides. Compared with FFM index, the equivalent increase in FM index showed a greater decrease in HDL-C. CONCLUSION: Greater BMI was related to adverse levels of blood lipids in children and adolescents, which was mainly attributable to BMI's fat component. It is important to identify weight management strategies to halt the childhood obesity epidemic and subsequently prevent heart disease in adulthood.

  10. Proarrhythmic electrical remodelling is associated with increased beat-to-beat variability of repolarisation

    DEFF Research Database (Denmark)

    Thomsen, Morten Bækgaard; Oros, Avram; Schoenmakers, Marieke

    2007-01-01

    Acquired long-QT syndrome in combination with increased beat-to-beat variability of repolarisation duration (BVR) is associated with lethal torsades de pointes arrhythmias (TdP) in dogs with remodelled heart after atrioventricular block (AVB). We evaluated the relative contributions of bradycardia...

  11. Intracardiac metastasis of immature teratoma after chemotherapy in a patient with testicular mixed germ cell tumor

    Directory of Open Access Journals (Sweden)

    Wei-Chih Chang

    2017-12-01

    Full Text Available Cancer with intra-cardiac metastasis is a rare complication. We herein report a 32-year-old male diagnosed with stage IV mixed germ cell tumor of the testes who received right radical orchiectomy. Initially, he had right lung metastasis and a mediastinal lymph node attached to the right side of the heart. After four cycles of chemotherapy (bleomycin, etoposide, and cisplatin, the patient experienced sudden cardiac arrest. He was later found to have intra-cardiac metastasis with tumor invasion in the right pulmonary artery/veins, left atrium, and left ventricle. The patient subsequently received surgical intervention, and pathology revealed only immature teratoma. This study illustrates the proposition that chemo-resistant residual teratoma can still invade the heart after chemotherapy, and therefore surgical intervention might be needed.

  12. 67. Do prenatal intracardiac echogenic foci affect postnatal cardiac function?

    Directory of Open Access Journals (Sweden)

    R. Bader

    2016-07-01

    Full Text Available Echogenic foci in the prenatal hear is not an uncommon finding. To determine whether prenatally diagnosed intracardiac echogenic foci are associated with neonatal cardiac dysfunction and persistence. Fetuses in which intracardiac echogenic foci were shown on prenatal sonography at 1 perinatal center from (September 2009 to December 2013 underwent postnatal echocardiography at ages 1 month to1 year. A single pediatric cardiologist assessed cardiac function by measuring the left ventricular shortening fraction and myocardial performance index. The presence of tricuspid valve regurgitation was also sought. Prenatally 60 fetuses had intracardiac echogenic foci mean age ± SD at diagnosis (23 ± 3.1. 53 (88.3% had left ventricular intracardiac echogenic foci, and 7 (11.6% had right ventricular intracardiac echogenic foci. 12 preganant ladies were lost for follow up (2 fetuses of 7 (28.5% with right ventricular intracardiac echogenic foci., and 10 fetuses of 53 (18.8% with LV intracardiac echogenic foci %. Post natally, those infants, 32 (66.6% males and 16 (33.3% females were examined. At a mean age ± SD of 7.4 ± 3.1 months. Prenatally, all infants had a normal left ventricular shortening fraction. The overall mean left ventricular myocardial performance index (reference value, 0.36 ± 0.06, was normal for both infants with left ventricular intracardiac echogenic foci (0.32 ± 0.01 and those with right ventricular intracardiac echogenic foci (0.33 ± 0.05. Trace tricuspid valve regurgitation were noted in 15 (31% of the infants. Left ventricular intracardiac echogenic foci persisted in 15 infants (34.8%, whereas right ventricular intracardiac echogenic foci persisted in 1 infant (20%. Prenatally diagnosed intracardiac echogenic foci can be persistent but is not associated with myocardial dysfunction in the first year of life.

  13. Study of intracardiac blood flow by MRI using gradient echo method

    Energy Technology Data Exchange (ETDEWEB)

    Ohnishi, Shusaku; Fukui, Sugao; Atsumi, Chisato; Morita, Ruriko; Kusuoka, Hideo; Fujii, Kenshi; Kitabatake, Akira; Takizawa, Osamu.

    1988-06-01

    In order to investigate the possibility of MR imaging for the evaluation of intracardiac blood flow especially valvular regurgitant flow, we obtained MR images using a 1.5 tesla superconductive magnet system (Siemens Medical) in 3 healthy volunteers, 3 patients with hypertrophic cardiomyopathy and 8 patients with valvular heart disease. Rapid FLASH (Fast Low-Angle Shot) imaging technique was applied to collect 11 time frames per section throughout one cardiac cycle in axial, coronal, saggital and oblique sections. Then these sequential frames were displayed in a cine mode on CRT. (1) Intracardiac and intravascular blood flow were visualized with high signal intensity in each frame and cardiac structures such as atria, ventricles, and aorta were also identified in all subjects. (2) Ventricular ejection flow was easily visualized in coronal section as the signal loss in the ascending aorta. Ventricularfilling was visualized in axial and oblique sections as the high signal influx of atrial blood into the ventricle. (3) In 3 patients with aortic regurgitation, regurgitant flow was detected during diastole as the teardrop shaped signal loss originating from aortic valve cusps. (4) Both mitral and tricuspid regurgitant flow were detected during systole as the signal loss in atrium in axial and oblique sections in 2 patients with MR and 2 patients with TR. (5) Pulmonary regurgitant flow was observed in oblique section along the long axis of right ventricular outflow tract. These results indicate that intracardiac forward and regurgitant flow could be identified with rapid FLASH imaging in normal subjects and in patients with valvular heart diseases, and cine mode MR imaging is a useful tool for the evaluation of intracardiac blood flow.

  14. Beat-to-beat QT dynamics in healthy subjects

    DEFF Research Database (Denmark)

    Jensen, Berit T; Larroude, Charlotte E; Rasmussen, Lars P

    2004-01-01

    measurements is still unsettled. The aims of the present study were: (1) to describe the reproducibility of beat-to-beat QT dynamics with respect to intrasubject, between-subject, and between-observer variability and (2) to describe the normal range, circadian variation, and heart rate dependence of QT...... dynamics. METHODS: Ambulatory Holter recordings were performed three times on 20 healthy volunteers and were analyzed by two experienced cardiologists. Slope and intercept of the QT/RR regression, the variability of QT and R-R intervals expressed as the standard deviation, and the relation between QT...... and RR variability expressed as a variability ratio were measured among other QT dynamics. RESULTS: The reproducibility of all QT dynamics was good. All QT dynamics showed circadian variation when calculated on an hourly basis. The day/night variation in slope could be explained by the differences...

  15. New approach to intracardiac hemodynamic measurements in small animals

    DEFF Research Database (Denmark)

    Eskesen, Kristian; Olsen, Niels T; Dimaano, Veronica L

    2012-01-01

    Invasive measurements of intracardiac hemodynamics in animal models have allowed important advances in the understanding of cardiac disease. Currently they are performed either through a carotid arteriotomy or via a thoracotomy and apical insertion. Both of these techniques have disadvantages...... and are not conducive to repeated measurements. Therefore, the purpose of this study was to develop a new technique for measuring intracardiac hemodynamics....

  16. Efeito da ginástica funcional sobre a pressão arterial, frequência cardíaca e duplo produto em mulheres Acute effects of functional gymnastic training on blood pressure, heart beat rate and heart beat-pressure product in females

    Directory of Open Access Journals (Sweden)

    Estélio Henrique Martin Dantas

    2011-09-01

    Full Text Available Objetivo do estudo foi verificar efeitos do treinamento funcional sobre a pressão arterial sistólica (PAS e diastólica (PAD, freqüência cardíaca (FC e duplo produto (DP de 24 mulheres inexperientes (25 ± 5 anos; 53 ± 6 kg; 164 ± 5 cm; IMC = 23,09 ± 2,64; 22,99 ± 3,38% de Gordura. Realizou-se uma aula de treinamento funcional e uma seqüência controle. As variáveis foram observadas antes, logo após, 10, 20, 30, 40, 50 e 60 minutos após o treinamento. A ANOVA observou diminuições significativas na PAS, a partir do vigésimo minuto (Δ% = 8,00%, p = 0,001 e na PAD, iniciando no décimo minuto (Δ% = 5,80%, p = 0,0002 em relação ao repouso. No momento logo após, a PAD obteve redução no trigésimo (Δ% = 5,85%, p = 0,0004 e qüinquagésimo minuto (Δ% = 4,14%, p = 0,006. Ocorreu um aumento na FC logo após a sessão (Δ% = 40,02%, p = 0,0001 e reduções a partir de 40 minutos após (Δ% = 7,95%, p = 0,01. O DP reduziu a partir de 20 minutos após o exercício (Δ% = 13,5%, p = 0,0002. O treinamento funcional reduziu significantemente a PAS, PAD, FC e DP após um treinamento em mulheres jovens.The effects of functional training sessions on systolic (SBP and diastolic (DBP blood pressure, heart beat rate (HR and heart beat-pressure product (HPP in 24 untrained women (25 ± 5 years; 53 ± 6 kg; 164 ± 5 cm; 23.09 ± 2.64 kg m-2; 22.99 ± 3.38% body fat were investigated. The subjects participated on a functional training class following by a control follow-up. Variables were registered prior to training exercise, and 10, 20, 30, 40, 50 and 60 minutes after training. Whereas ANOVA reported a significant decrease (p < 0.05 in SBP as from the twentieth minute (Δ% = 8.00%, p = 0.001, decrease in DBP started at the tenth minute (Δ% = 5.80%, p = 0.0002. Significant decreases were observed at the thirtieth (Δ% = 5.85%, p = 0.0004 and fiftieth (Δ% = 4.14%, p = 0.006 minute. HR increase was reported immediately after the test (Δ% = 40

  17. Beating-heart, off-pump mitral valve repair by implantation of artificial chordae tendineae: an acute in vivo animal study.

    Science.gov (United States)

    Bajona, Pietro; Katz, William E; Daly, Richard C; Zehr, Kenton J; Speziali, Giovanni

    2009-01-01

    To evaluate the effectiveness of a new off-pump mitral valve repair technology in restoring valve competency in a porcine model of acute mitral regurgitation. Acute mitral regurgitation was induced in 6 anesthetized pigs by cutting anterior leaflet chordae. Artificial chordae were then transapically implanted on the prolapsing segment under epicardial echocardiographic guidance and secured outside the left ventricular apex. All intracardiac manipulations were performed off-pump, through a stab wound incision on the left ventricular apex. Cutting the anterior leaflet chordae caused an eccentric, posteriorly directed jet of mitral regurgitation that could be visualized by color Doppler sonography. Implantation of chordae through the left ventricular apex completely eliminated valve regurgitation in 4 animals and reduced regurgitation in 2. Intraoperative measurement of artificial chordal tensions gave similar values to those reported for native chordae. Off-pump, transapical implantation of artificial chordae between a prolapsing anterior mitral valve leaflet and the left ventricular apex was effective in reducing acutely induced mitral regurgitation. Long-term studies are planned to assess the stability in this animal model.

  18. Heritability of Ambulatory and Beat-to-Beat Office Blood Pressure in Large Multigenerational Arab Pedigrees : The 'Oman Family Study'

    NARCIS (Netherlands)

    Albarwani, Sulayma; Munoz, M. Loretto; Voruganti, V. Saroja; Jaju, Deepali; Al-Yahyaee, V. Saeed; Rizvi, Syed G.; Lopez-Alvarenga, Juan C.; Al-Anqoudi, Zahir M.; Bayoumi, Riad A.; Comuzzie, Anthony G.; Snieder, Harold; Hassan, Mohammed O.

    2012-01-01

    Objective: To estimate the heritability of ambulatory blood pressure (BP), heart rate (HR), and beat-to-beat office BP and HR in an isolated, environmentally and genetically homogeneous Omani Arab population. Methods: Ambulatory BP measurements were recorded in 1,124 subjects with a mean age of 33.8

  19. Intracardiac metastasis of squamous cell carcinoma of the penis

    Directory of Open Access Journals (Sweden)

    Sheila Aparecida Coelho Siqueira

    2013-12-01

    Full Text Available Penile cancer shows variable incidence in different countries with a higher prevalence in developing countries. Squamous cell carcinoma represents the most common histologic type. The seventh decade of life corresponds to the mean age at diagnosis, but it is not an unusual diagnosis among young adults. Most cases present as “in situ” neoplasia or loco regional disease; however, systemic disseminated disease occurs via lymphatic and/or hematogeneous routes. The lymph nodes, liver, and lungs are the most frequently involved sites whereas the heart constitutes an exceptional and atypical site for penile cancer metastases. We report a case of a 79-year-old patient who presented a metastatic squamous cell carcinoma of the penis with intracardiac dissemination. The patient had a past history of cardiomyopathy, which required an artificial cardiac pacemaker implantation. He had been treated 1 year before with a partial penectomy but was admitted for emasculation due to the cancer relapse. During the postoperative period, he experienced sudden respiratory distress and died. The autopsy findings showed metastatic disease into the cardiac right chambers, pulmonary tumoral thrombi, and pulmonary hilar involvement. The authors call attention to the possibility of the presence of pacing leads, cardiomyopathy and the altered low blood flow in the right chambers, as predisposing factors for the tumoral seeding in this case.

  20. Political Outlaws: Beat Cowboys

    Directory of Open Access Journals (Sweden)

    Kurt Hemmer

    2007-12-01

    Full Text Available This paper examines the specific cultural landscape of the liminal locale of bohemia during the specific historical moment of the Beat Generation (1950–1965 to examine how the elements of the outlaw figure were transformed by the Beat writers to fend off the Eisenhower-era containment culture.

  1. Functional pulmonary atresia in newborn with normal intracardiac anatomy: Successful treatment with inhaled nitric oxide and pulmonary vasodilators

    Directory of Open Access Journals (Sweden)

    Gürkan Altun

    2013-01-01

    Full Text Available Functional pulmonary atresia is characterized by a structurally normal pulmonary valve that does not open during right ventricular ejection. It is usually associated with Ebstein′s anomaly, Uhl′s anomaly, neonatal Marfan syndrome and tricuspid valve dysplasia. However, functional pulmonary atresia is rarely reported in newborn with anatomically normal heart. We report a newborn with functional pulmonary atresia who had normal intracardiac anatomy, who responded to treatment with nitric oxide and other vasodilator therapy successfully.

  2. Successful intracardiac robotic surgery: initial results from Japan.

    Science.gov (United States)

    Watanabe, Go

    2010-01-01

    : The purpose of this study is to report our 2-year experience of performing endoscopic intracardiac procedures using the da Vinci Surgical System. Our teams at Kanazawa University and Tokyo Medical University groups began using the da Vinci Surgical System (Intuitive Surgical, Inc, Sunnyvale, CA) in 2005. This series represents the first Japanese application of robotic technology for totally endoscopic open-heart surgery. : From January 2008 to February 2009, 10 patients (mean age: 46.8 ± 16.3 years, 70% women) underwent endoscopic atrial septal defect closure and resection of the left atrial myxoma using the da Vinci Surgical System and peripheral cardiopulmonary bypass technique. Of the 10 patients, nine were classified as New York Heart Association class II and 1 patient exhibited atrial arrhythmias. In addition, two patients required mitral valve plasty (n = 2) and tricuspid annuloplasty (n = 1). : Mean da Vinci Surgical System working time was 140.7 ± 57.4 minutes. Mean cardiopulmonary bypass and aortic cross clamp times were 103.1 ± 37.1 and 30.0 ± 16.9 minutes, respectively. There were no conversions to sternotomy or small thoracotomy. There were no hospital deaths. Mean intensive care unit and hospital stays were 1 day and 3.1 ± 0.3 days, respectively. All patients appreciated the cosmetic result and fast recovery. : Closed-chest atrial septal defect closure and myxoma resection performed using robotic techniques achieved excellent results and rapid postoperative recovery and provided an attractive cosmetic advantage over median sternotomy.

  3. Up-Beat UK: A programme of research into the relationship between coronary heart disease and depression in primary care patients

    Directory of Open Access Journals (Sweden)

    Pariante Carmine M

    2011-05-01

    Full Text Available Abstract Background Coronary heart disease and depression are both common health problems and by 2020 will be the two leading causes of disability worldwide. Depression has been found to be more common in patients with coronary heart disease but the nature of this relationship is uncertain. In the United Kingdom general practitioners are now being remunerated for case-finding for depression in patients with coronary heart disease, however it is unclear how general practitioners should manage these patients. We aim to explore the relationship between coronary heart disease and depression in a primary care population and to develop an intervention for patients with coronary heart disease and depression. Methods/design This programme of research will consist of 4 inter-related studies. A 4 year prospective cohort study of primary care patients with coronary heart disease will be conducted to explore the relationship between coronary heart disease and depression. Within this, a nested case-control biological study will investigate genetic and blood-biomarkers as predictors of depression in this sample. Two qualitative studies, one of patients' perspectives of treatments for coronary heart disease and co-morbid depression and one of primary care professionals' views on the management of patients with coronary heart disease and depression will inform the development of an intervention for this patient group. A feasibility study for a randomised controlled trial will then be conducted. Discussion This study will provide information on the relationship between coronary heart disease and depression that will allow health services to determine the efficiency of case-finding for depression in this patient group. The results of the cohort study will also provide information on risk factors for depression. The study will provide evidence on the efficacy and feasibility of a joint patient and professional led intervention and data necessary to plan a

  4. Binaural beat salience.

    Science.gov (United States)

    Grose, John H; Buss, Emily; Hall, Joseph W

    2012-03-01

    Previous studies of binaural beats have noted individual variability and response lability, but little attention has been paid to the salience of the binaural beat percept. The purpose of this study was to gauge the strength of the binaural beat percept by matching its salience to that of sinusoidal amplitude modulation (SAM), and to then compare rate discrimination for the two types of fluctuation. Rate discrimination was measured for standard rates of 4, 8, 16, and 32 Hz - all in the 500-Hz carrier region. Twelve normal-hearing adults participated in this study. The results indicated that discrimination acuity for binaural beats is similar to that for SAM tones whose depths of modulation have been adjusted to provide equivalent modulation salience. The matched-salience SAM tones had relatively shallow depths of modulation, suggesting that the perceptual strength of binaural beats is relatively weak, although all listeners perceived them. The Weber fraction for detection of an increase in binaural beat rate is roughly constant across beat rates, at least for rates above 4 Hz, as is rate discrimination for SAM tones. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Data and Statistics: Heart Failure

    Science.gov (United States)

    ... Blood Pressure Salt Cholesterol Million Hearts® WISEWOMAN Heart Failure Fact Sheet Recommend on Facebook Tweet Share Compartir ... mean that the heart has stopped beating. Heart Failure in the United States About 5.7 million ...

  6. On binaural beats.

    Science.gov (United States)

    Fritze, W

    1985-01-01

    Binaural beats have been investigated in normal volunteers using high-stable synthesizers. There are considerable differences between the subjective rhythm heard and the difference of the two frequencies, indicating that this dissimilarity must be caused centrally.

  7. Relationship between catheter contact force and radiofrequency lesion size and incidence of steam pop in the beating canine heart: electrogram amplitude, impedance, and electrode temperature are poor predictors of electrode-tissue contact force and lesion size.

    Science.gov (United States)

    Ikeda, Atsushi; Nakagawa, Hiroshi; Lambert, Hendrik; Shah, Dipen C; Fonck, Edouard; Yulzari, Aude; Sharma, Tushar; Pitha, Jan V; Lazzara, Ralph; Jackman, Warren M

    2014-12-01

    Electrode-tissue contact force (CF) is believed to be a major factor in radiofrequency lesion size. The purpose of this study was to determine, in the beating canine heart, the relationship between CF and radiofrequency lesion size and the accuracy of predicting CF and lesion size by measuring electrogram amplitude, impedance, and electrode temperature. Eight dogs were studied closed chest. Using a 7F catheter with a 3.5 mm irrigated electrode and CF sensor (TactiCath, St. Jude Medical), radiofrequency applications were delivered to 3 separate sites in the right ventricle (30 W, 60 seconds, 17 mL/min irrigation) and 3 sites in the left ventricle (40 W, 60 seconds, 30 mL/min irrigation) at (1) low CF (median 8 g); (2) moderate CF (median 21 g); and (3) high CF (median 60 g). Dogs were euthanized and lesion size was measured. At constant radiofrequency and time, lesion size increased significantly with increasing CF (Pradiofrequency application correlated well with lesion size for lesions in the left ventricle but less well for lesions in the right ventricle. There was a poor relationship between CF and the amplitude of the bipolar or unipolar ventricular electrogram, unipolar injury current, and impedance. Radiofrequencylesion size and the incidence of steam pop increase strikingly with increasing CF. Electrogram parameters and initial impedance are poor predictors of CF for radiofrequency ablation. © 2014 American Heart Association, Inc.

  8. Binaural Beat: A Failure to Enhance EEG Power and Emotional Arousal.

    Science.gov (United States)

    López-Caballero, Fran; Escera, Carles

    2017-01-01

    When two pure tones of slightly different frequencies are delivered simultaneously to the two ears, is generated a beat whose frequency corresponds to the frequency difference between them. That beat is known as acoustic beat. If these two tones are presented one to each ear, they still produce the sensation of the same beat, although no physical combination of the tones occurs outside the auditory system. This phenomenon is called binaural beat. In the present study, we explored the potential contribution of binaural beats to the enhancement of specific electroencephalographic (EEG) bands, as previous studies suggest the potential usefulness of binaural beats as a brainwave entrainment tool. Additionally, we analyzed the effects of binaural-beat stimulation on two psychophysiological measures related to emotional arousal: heart rate and skin conductance. Beats of five different frequencies (4.53 Hz -theta-, 8.97 Hz -alpha-, 17.93 Hz -beta-, 34.49 Hz -gamma- or 57.3 Hz -upper-gamma) were presented binaurally and acoustically for epochs of 3 min (Beat epochs), preceded and followed by pink noise epochs of 90 s (Baseline and Post epochs, respectively). In each of these epochs, we analyzed the EEG spectral power, as well as calculated the heart rate and skin conductance response (SCR). For all the beat frequencies used for stimulation, no significant changes between Baseline and Beat epochs were observed within the corresponding EEG bands, neither with binaural or with acoustic beats. Additional analysis of spectral EEG topographies yielded negative results for the effect of binaural beats in the scalp distribution of EEG spectral power. In the psychophysiological measures, no changes in heart rate and skin conductance were observed for any of the beat frequencies presented. Our results do not support binaural-beat stimulation as a potential tool for the enhancement of EEG oscillatory activity, nor to induce changes in emotional arousal.

  9. Binaural Beat: A Failure to Enhance EEG Power and Emotional Arousal

    Directory of Open Access Journals (Sweden)

    Fran López-Caballero

    2017-11-01

    Full Text Available When two pure tones of slightly different frequencies are delivered simultaneously to the two ears, is generated a beat whose frequency corresponds to the frequency difference between them. That beat is known as acoustic beat. If these two tones are presented one to each ear, they still produce the sensation of the same beat, although no physical combination of the tones occurs outside the auditory system. This phenomenon is called binaural beat. In the present study, we explored the potential contribution of binaural beats to the enhancement of specific electroencephalographic (EEG bands, as previous studies suggest the potential usefulness of binaural beats as a brainwave entrainment tool. Additionally, we analyzed the effects of binaural-beat stimulation on two psychophysiological measures related to emotional arousal: heart rate and skin conductance. Beats of five different frequencies (4.53 Hz -theta-, 8.97 Hz -alpha-, 17.93 Hz -beta-, 34.49 Hz -gamma- or 57.3 Hz -upper-gamma were presented binaurally and acoustically for epochs of 3 min (Beat epochs, preceded and followed by pink noise epochs of 90 s (Baseline and Post epochs, respectively. In each of these epochs, we analyzed the EEG spectral power, as well as calculated the heart rate and skin conductance response (SCR. For all the beat frequencies used for stimulation, no significant changes between Baseline and Beat epochs were observed within the corresponding EEG bands, neither with binaural or with acoustic beats. Additional analysis of spectral EEG topographies yielded negative results for the effect of binaural beats in the scalp distribution of EEG spectral power. In the psychophysiological measures, no changes in heart rate and skin conductance were observed for any of the beat frequencies presented. Our results do not support binaural-beat stimulation as a potential tool for the enhancement of EEG oscillatory activity, nor to induce changes in emotional arousal.

  10. Retrieval of a Dislodged Catheter Using Combined Fluoroscopy and Intracardiac Echocardiography

    Directory of Open Access Journals (Sweden)

    Gus Mitsopoulos

    2015-01-01

    Full Text Available This report details a method of percutaneous, transluminal retrieval of an intracardiac foreign body using fluoroscopy in combination with intracardiac echocardiography. During retrieval, intracardiac echocardiography (ICE provided real-time anatomic localization of a constantly moving, almost radiolucent micropuncture coaxial dilator fragment with respect to the tricuspid and pulmonary valves. This method may serve as a crucial aid in retrieval of intracardiac foreign bodies that are difficult to see with fluoroscopy and which may be adjacent to cardiac valves.

  11. Retrieval of a Dislodged Catheter Using Combined Fluoroscopy and Intracardiac Echocardiography.

    Science.gov (United States)

    Mitsopoulos, Gus; Hanna, Robert F; Brejt, Sidney Z; Goldstein, Greg E; Sheynzon, Vladimir; Weintraub, Joshua L; Gray, William A

    2015-01-01

    This report details a method of percutaneous, transluminal retrieval of an intracardiac foreign body using fluoroscopy in combination with intracardiac echocardiography. During retrieval, intracardiac echocardiography (ICE) provided real-time anatomic localization of a constantly moving, almost radiolucent micropuncture coaxial dilator fragment with respect to the tricuspid and pulmonary valves. This method may serve as a crucial aid in retrieval of intracardiac foreign bodies that are difficult to see with fluoroscopy and which may be adjacent to cardiac valves.

  12. Hyperosmotic perfusion of the beating rat heart and the role of the Na+/K+/2Cl- co-transporter and the Na+/H+ exchanger.

    Science.gov (United States)

    Falck, G; Schjøtt, J; Bruvold, M; Krane, J; Skarra, S; Jynge, P

    2000-02-01

    The aim of the present study was to investigate the role of the Na+/K+/2Cl- co-transporter and the Na+/H+ exchanger on contractile function and electrolyte regulation during hyperosmotic perfusion of the heart. Langendorff perfused rat hearts were subjected to hyperosmolal perfusion in 10-min intervals. Perfusates were made hyperosmotic by adding mannitol to the buffer (370, 450 and 600 mOsmol/kg H2O). Cardiac contractile function was monitored with a balloon in the left ventricle (LV) coupled to a pressure transducer. Cardiac effluent was sampled repeatedly throughout and after hyperosmotic perfusion and analysed for content of Na+, K+, and Cl-. All three hyperosmotic perfusates initially reduced LV developed pressure (LVDP), but for 370 and 450 mOsmol/kg H2O, LVDP recovered to baseline within 4 min of perfusion. With 600 mOsmol/kg H2O, LVDP recovered slowly and was 50% below baseline after 10 min of hyperosmotic perfusion. Inhibition of the Na+/H+ exchanger with 5-(N-ethyl-N-isopropyl) amiloride (EIPA) and 3-methylsulfonyl-4-piperidinobenzoyl-guanidine methanesulfonate (HOE 694) abolished the recovery of LVDP to the 600 mOsmol/kg H2O perfusate, whereas inhibition of the Na+/K+/2Cl- co-transporter had no impact on LVDP. Potassium was taken up by the heart during hyperosmotic perfusion and this uptake was significantly reduced with inhibition of the Na+/H+ exchanger. Intracellular pH was assessed with 31p magnetic resonance spectroscopy and hyperosmolality induced a significant alkalosis that was dependent upon the Na+/H+ exchanger. The rat heart responds to moderate elevations in osmolality with a transient reduction in contractile function, whereas an elevation of 300 mOsmol/kg H2O persistently reduces contractile function. The Na+/H+ exchanger, but not the Na+/K+/2Cl- co-transporter, is of importance in contractile recovery and electrolyte regulation during hyperosmotic perfusion in the rat heart.

  13. Wearable Beat to Beat Blood Pressure Monitor, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — A key component of NASA's human exploration programs is a system that monitors the health of the crew during space missions. The wearable beat-to-beat blood pressure...

  14. Europe’s Wild Heart – still beating? Experiences from a new transboundary wilderness area in the middle of the Old Continent

    Directory of Open Access Journals (Sweden)

    Zdenka Křenová

    2013-03-01

    Full Text Available The face of Europe has been shaped by human civilization for centuries and wilderness did not only vanish from the continent’s surface but also from humans’ minds and experiences. However, there are still a few places left, which have remained more or less unmodified and have at least the potential for rewilding. Among them are the Šumava National Park and the neighbouring Bavarian Forest NP, which together create a unique forest zone in the middle of Europe susceptible to host and demonstrate natural forest dynamics and ecosystem processes. This is also a large and very important Natura 2000 area. Transboundary cooperation between both National parks has improved since 1990, when the former Iron Curtain Corridor was opened, and culminated by the project Europe’s Wild Heart. The main goal of the project Europe’s Wild Heart, which started in 2008, was to develop a transboundary wilderness area in the core zones of the two national parks – BFNP and ŠNP. The project area was 13,060 ha and a “life story” of this project is described in this paper. A common “vision 2020” was signed where both parks committed among other things “to achieve a joint core area of about 15,000 ha with harmonized management principles, information services and monitoring networks to officially become the first and largest transboundary wilderness area in Central Europe”. Unfortunately, the bark beetle outbreak which followed the Kyrill hurricane in 2008 and 2009 escalated the discussion about appropriate forest management in the ŠNP. Opponents of the national park principles, non-intervention and wilderness concept became more and more vocal. The situation escalated after the election in 2010 when the Green Party was replaced by conservatives (ODS – Civic Democratic Party at the Czech Ministry of Environment. Clear cuttings were started in some former non-intervention parts of the ŠNP and hunting was again allowed in the core zone. Since then

  15. Detection of intracardiac thrombi by scintiphotography with 111In-labeled autologous platelets

    International Nuclear Information System (INIS)

    Yui, Tokuo; Uchida, Tatsumi; Matsuda, Shin

    1982-01-01

    Detection of intracardiac thrombi by scintigraphy with In-111-oxine labeled autologous platelets was studied in 14 patients with various heart diseases. The results of platelet scintigraphy were compared with those of two dimensional echocardiography. In 4 of the 14 patients, the findings on platelet scintigraphy and echocardiography were both positive. Left atrial thrombi were detected in 3 patients with mitral valve disease (MVD), and left ventricular thrombus in a patient with myocardial infarction with left ventricular aneurysm (MI). The scintigraphy after antiplatelet therapy in the patient with MI did not show any radioactivity on the thrombus. In one of the 14 patients with MVD, the finding on platelet scintigraphy was positive, on the other hand echocardiography was negative. In one of the 14 patients with MVD, the finding on platelet scintigraphy was negative, on the other hand that on echocardiography was positive. The thrombus in this case may be hematologically nonactive thrombus. In-111 platelet scintigraphy is considered to be an excellent method for the diagnosis and in vivo assessment of antithrombotic therapy on intracardiac thrombosis. (J.P.N.)

  16. Late termination of pregnancy by intracardiac potassium chloride ...

    African Journals Online (AJOL)

    Objectives. To report our experience with intracardiac potassium chloride (KCl) injection as a method of feticide for severe congenital abnormalities beyond 24 weeksf gestation. Method. A retrospective chart review. Patient demographics and types of fetal anomalies were analysed according to the groups that accepted

  17. Infrarenal transcaval extraction of intracardiac leiomyomatosis.

    Science.gov (United States)

    Hinojosa, Carlos A; Medina-Franco, Heriberto; Orozco-Zepeda, Vicente; Martinez Mijangos, Omar; Valdes, Karen A; Aragon Han, Patricia

    2013-02-01

    Intravascular leiomyomatosis is a rare, histologically benign disease, and can spread through the venous system to the right cavities of the heart. We report the case of a 39-year-old woman who presented with intravenous leiomyomatosis with extension to the right ventricle, causing heart failure. She underwent surgery successfully, undergoing a total resection of this tumor through the infrarenal cava and the hysterectomy in one surgical stage. Surgical technique considerations are discussed and the literature is reviewed. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Mesenchymal stem cells improve mouse non-heart-beating liver graft survival by inhibiting Kupffer cell apoptosis via TLR4-ERK1/2-Fas/FasL-caspase3 pathway regulation

    Directory of Open Access Journals (Sweden)

    Yang Tian

    2016-10-01

    Full Text Available Abstract Background Liver transplantation is the optimal treatment option for end-stage liver disease, but organ shortages dramatically restrict its application. Donation after cardiac death (DCD is an alternative approach that may expand the donor pool, but it faces challenges such as graft dysfunction, early graft loss, and cholangiopathy. Moreover, DCD liver grafts are no longer eligible for transplantation after their warm ischaemic time exceeds 30 min. Mesenchymal stem cells (MSCs have been proposed as a promising therapy for treatment of certain liver diseases, but the role of MSCs in DCD liver graft function remains elusive. Methods In this study, we established an arterialized mouse non-heart-beating (NHB liver transplantation model, and compared survival rates, cytokine and chemokine expression, histology, and the results of in vitro co-culture experiments in animals with or without MSC infusion. Results MSCs markedly ameliorated NHB liver graft injury and improved survival post-transplantation. Additionally, MSCs suppressed Kupffer cell apoptosis, Th1/Th17 immune responses, chemokine expression, and inflammatory cell infiltration. In vitro, PGE2 secreted by MSCs inhibited Kupffer cell apoptosis via TLR4-ERK1/2-caspase3 pathway regulation. Conclusion Our study uncovers a protective role for MSCs and elucidates the underlying immunomodulatory mechanism in an NHB liver transplantation model. Our results suggest that MSCs are uniquely positioned for use in future clinical studies owing to their ability to protect DCD liver grafts, particularly in patients for whom DCD organs are not an option according to current criteria.

  19. Disturbance of intracardiac hemodynamics in children with chronic rheumatic cardiac disease

    Directory of Open Access Journals (Sweden)

    Kondratiev V.A.

    2013-12-01

    Full Text Available By means of Doppler echocardiography there have been studied disturbances of intracardiac hemodynamics in 44 children aged 8-17 years with chronic rheumatic cardiac disease and developed mitral aortal and combined heart defects, as well as in chronic rheumatic cardiac disease without developed valvar defect. Differential approach has been defined to administration of inhibitors of angiotensin-converting factor in rheumatic heart defects: developed insufficiency of mitral and/or aortal valves II-III stage leads to remodeling of the left heart portions with developing chronic insufficiency of blood circulation, being an index for prolonged, not less than a year usage of the angiotensin-converting factor. In the presence of isolated mitral regurgitation, I stage in children with chronic rheumatic cardiac disease usage of the angiotensin-converting factor may be cancelled due to insignificant disturbances of valvar hemodynamics and a small risk of developing blood circulation insufficiency. Timely sanation of chronic infection foci in nasopharynx (conservative and surgical treatment of chronic tonsillitis, adenoid vegetations, therapy of hemolytic streptococcus presence decreases risk of developing rheumatic heart defect in children suffered acute rheumatic fever.

  20. A quantitative high resolution voxel-wise assessment of myocardial blood flow from contrast-enhanced first-pass magnetic resonance perfusion imaging: microsphere validation in a magnetic resonance compatible free beating explanted pig heart model.

    Science.gov (United States)

    Schuster, Andreas; Sinclair, Matthew; Zarinabad, Niloufar; Ishida, Masaki; van den Wijngaard, Jeroen P H M; Paul, Matthias; van Horssen, Pepijn; Hussain, Shazia T; Perera, Divaka; Schaeffter, Tobias; Spaan, Jos A E; Siebes, Maria; Nagel, Eike; Chiribiri, Amedeo

    2015-10-01

    To assess the feasibility of high-resolution quantitative cardiovascular magnetic resonance (CMR) voxel-wise perfusion imaging using clinical 1.5 and 3 T sequences and to validate it using fluorescently labelled microspheres in combination with a state of the art imaging cryomicrotome in a novel, isolated blood-perfused MR-compatible free beating pig heart model without respiratory motion. MR perfusion imaging was performed in pig hearts at 1.5 (n = 4) and 3 T (n = 4). Images were acquired at physiological flow ('rest'), reduced flow ('ischaemia'), and during adenosine-induced hyperaemia ('stress') in control and coronary occlusion conditions. Fluorescently labelled microspheres and known coronary myocardial blood flow represented the reference standards for quantitative perfusion validation. For the comparison with microspheres, the LV was divided into 48 segments based on a subdivision of the 16 AHA segments into subendocardial, midmyocardial, and subepicardial subsegments. Perfusion quantification of the time-signal intensity curves was performed using a Fermi function deconvolution. High-resolution quantitative voxel-wise perfusion assessment was able to distinguish between occluded and remote myocardium (P < 0.001) and between rest, ischaemia, and stress perfusion conditions at 1.5 T (P < 0.001) and at 3 T (P < 0.001). CMR-MBF estimates correlated well with the microspheres at the AHA segmental level at 1.5 T (r = 0.94, P < 0.001) and at 3 T (r = 0.96, P < 0.001) and at the subendocardial, midmyocardial, and subepicardial level at 1.5 T (r = 0.93, r = 0.9, r = 0.88, P < 0.001, respectively) and at 3 T (r = 0.91, r = 0.95, r = 0.84, P < 0.001, respectively). CMR-derived voxel-wise quantitative blood flow assessment is feasible and very accurate compared with microspheres. This technique is suitable for both clinically used field strengths and may provide the tools to assess extent and severity of myocardial ischaemia. Published on behalf of the European Society

  1. The effect of low-dose β-blocker on heart rate and heart rate variability in health subjects wth a resting heart rate of less than 65 beats per minute: Effect on the quality of prospective electrocardiography-gated coronary CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chul Hwan; Kim, Tae Hoon [Dept. of Radiology and Research Institute of Radiological Science, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Lee, Sang Min [Dept. of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Hong, Yoo Jin [Dept. of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2015-02-15

    We assessed the effect of a low-dose β-blocker on heart rate (HR), HR variability (HRV) and image quality of prospective electrocardiography-gated coronary CT angiography (CCTA) in healthy subjects with low HR. CCTA was performed with a 64-slice CT in 75 subjects with a HR of less than 65 beats per minute (bpm). Subjects were divided into 2 groups: Group 1 (G1), 35 with a low dose β-blocker; and Group 2 (G2), 40 without pre-medication. The image quality (IQ) of the CCTA was assessed on a 4-point grading scale (1, poor; 4, excellent). Initial HR (bpm) was not different between the 2 groups. HR during CCTA was lower in G1 than G2 (50.3 ± 5.6 vs. 53.3 ± 4.8, p = 0.016). HRV was not different between the 2 groups. Per-segment analysis showed better IQ at the mid-segment of the right coronary artery (3.0 ± 0.9 vs. 2.5 ± 1.1, p = 0.039) and the first diagonal branch (3.4 ± 0.6 vs. 3.1 ± 0.7, p = 0.024), in the G1 than the G2 group, respectively. The IQ was negatively correlated with HR, but no correlation was found between HRV and IQ. The IQs in the per-vessel analysis were not different between the 2 groups. Low-dose β-blocker reduced HR and improved the IQ of CCTA in a few segments, even at a HR of less than 65 bpm. However the effect was limited.

  2. Nickel allergy, Kounis syndrome and intracardiac metal devices.

    Science.gov (United States)

    Almpanis, George C; Tsigkas, Grigorios G; Koutsojannis, Constantinos; Mazarakis, Andreas; Kounis, George N; Kounis, Nicholas G

    2010-11-19

    Metal-induced allergic reactions are not rare in every day practice but nickel, cobalt and chromium are the most common offenders. Other metal anions and metal alloys represent also emerging causes for hypersensitivity reaction in humans. The metal struts of endovascular and intracardiac devices are usually alloys containing nickel and constitute causes for allergic reactions with possible intracardiac and intracoronary mast cell activation resulting in the Kounis hypersensitivity coronary syndrome. Newer intracoronary stents avoid nickel thus making them less allergenic. It is advisable that, before any device implantation, careful history of any metal allergy should be taken and efforts should be made for the development of new devices with better biocompatibility. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  3. The birth of intracardiac surgery: a semicentennial tribute (June 10, 1948-1998)

    Science.gov (United States)

    Dávila, J C

    1998-06-01

    On June 10, 1948, Charles Philamore Bailey, of Philadelphia, auspiciously performed the first anatomically conceived and digitally guided operation inside the heart: the first successful intracardiac operation. The patient, Claire Ward, was a 24-year-old woman afflicted with severe mitral stenosis. Dwight E. Harken and Russell C. Brock performed their own mitral operations very soon after Bailey, using new variations of methods that had been discarded about two decades earlier; they soon adopted the logical anatomic approach. This threesome, with the added contributions of Robert P. Glover--Bailey's partner at the time, in the role of respected and convincing teacher--opened the floodgates upon a decade of so-called closed heart surgery. These accomplishments, added to the earlier successes with the patent ductus, aortic coarctation, and "blue babies," justified and strengthened the demand for precise diagnosis in cardiology--at that time a languishing specialty--and brought to the fore the indisputable requirement to operate inside the heart with maximal control. This essay calls attention to the semicentennial of that seminal event and reviews the origins of surgery for mitral stenosis.

  4. Oxidative shift in tissue redox potential increases beat-to-beat variability of action potential duration.

    Science.gov (United States)

    Kistamás, Kornél; Hegyi, Bence; Váczi, Krisztina; Horváth, Balázs; Bányász, Tamás; Magyar, János; Szentandrássy, Norbert; Nánási, Péter P

    2015-07-01

    Profound changes in tissue redox potential occur in the heart under conditions of oxidative stress frequently associated with cardiac arrhythmias. Since beat-to-beat variability (short term variability, SV) of action potential duration (APD) is a good indicator of arrhythmia incidence, the aim of this work was to study the influence of redox changes on SV in isolated canine ventricular cardiomyocytes using a conventional microelectrode technique. The redox potential was shifted toward a reduced state using a reductive cocktail (containing dithiothreitol, glutathione, and ascorbic acid) while oxidative changes were initiated by superfusion with H2O2. Redox effects were evaluated as changes in "relative SV" determined by comparing SV changes with the concomitant APD changes. Exposure of myocytes to the reductive cocktail decreased SV significantly without any detectable effect on APD. Application of H2O2 increased both SV and APD, but the enhancement of SV was the greater, so relative SV increased. Longer exposure to H2O2 resulted in the development of early afterdepolarizations accompanied by tremendously increased SV. Pretreatment with the reductive cocktail prevented both elevation in relative SV and the development of afterdepolarizations. The results suggest that the increased beat-to-beat variability during an oxidative stress contributes to the generation of cardiac arrhythmias.

  5. Heartbeat International: making "poor" hearts beat better.

    Science.gov (United States)

    Mond, Harry G; Mick, Wil; Maniscalco, Benedict S

    2009-10-01

    Heartbeat International is a little-known 501(c)(3) charitable organization, which for the past 25 years has been responsible for the implantation and follow-up of cardiac implantable electronic devices in over 9000 indigent recipients in predominantly developing countries. Although the concept was founded in Guatemala over 30 years ago, it took the vision and drive of Dr. Henry D. McIntosh, M.D., M.A.C.C, to create Heartbeat International in 1984. The organization works through Pacemaker Banks established by local Rotary International chapters and other civic organizations in 24 countries over four continents and is dependent on the generosity of the implantable device manufacturers and teams of dedicated physicians and hospital personnel in the countries of operation. Since the vast majority of personnel are voluntary, 90 cents of every donated dollar directly supports the provision, implantation of devices, and follow-up care. Each US$500 provides a pacemaker to one needy patient. The organization's co-mission is also to educate and train implanting physicians in pacing and implantable cardioverter-defibrillator technology. The program remains dependent on the pacemaker manufacturers, who work in an environment of regulatory constraint and economic imperatives. With an ever growing demand for these devices, Heartbeat International will in the future need to increase its operating budget to purchase implantable inventory.

  6. Heart beats from the dark side

    Science.gov (United States)

    Chang, Jin

    2018-01-01

    The Dark Matter Particle Explorer (DAMPE) satellite is currently in orbit measuring cosmic rays to research their origin and propagation and also to find possible hidden signatures of dark matter, emphasizes Principal Investigator Jin Chang.

  7. Distinguishing between overdrive excited and suppressed ventricular beats in guinea pig ventricular myocardium

    Directory of Open Access Journals (Sweden)

    Amara eGreer-Short

    2015-02-01

    Full Text Available Rapid ventricular pacing rates induces two types of beats following pacing cessation: recovery cycle length (RCL prolongation (overdrive suppression and RCL shortening (overdrive excitation. The goals of this study were to compare common experimental protocols for studying triggered activity in whole-heart preparations and differentiate between recovery beats using a new methodology. Post-pacing recovery beat cycle length (RCL and QRS were normalized to pre-paced R-R and QRS intervals and analyzed using a K-means clustering algorithm. Control hearts only produced suppressed beats: RCL ratio increased with rapid pacing (25±4.0%, n=10 without changing QRS duration. Rapid pacing during hypercalcemia + hypothermia (5.5 mM and 34°C produced significantly earlier excited beats (53±14%, n=5 with wider QRS durations (58±6.3%, n=5 than suppressed beats. Digoxin + hypothermia (0.75 M produced the most excited beats with significantly earlier RCL (44±3.2%, n=6 and wider QRS (60±3.1%, n=6 ratios relative to suppressed beats. Increasing pacing further shortened RCL (30±7.8%, n=6. In a prospective study, TTX (100 nM increased RCL ratio (15±6.0%, n=10 without changing the QRS duration of excited beats. The algorithm was compared to a cross-correlation analysis with 93% sensitivity and 94% specificity. This ECG based algorithm distinguishes between triggered and automatic activity.

  8. An unexpected complication of acute pancreatitis: Intra-cardiac thrombus.

    Science.gov (United States)

    Keskin, Muhammed; Gümüşdağ, Ayça; Börklü, Edibe Betül; Dayı, Şennur Ünal; Avcı, İlhan İlker; Güvenç, Tolga Sinan; Güngör, Barış; Karabay, Can Yücel; Kozan, Ömer

    2017-05-01

    Left atrial thrombus after acute pancreatitis (AP) is a rare clinical statement. Because of induction of systemic prothrombotic process by AP; some patients with underlying risk factors may develop an intra-cardiac thrombus. We present a 53years-old-woman with moderate mitral stenosis and atrial fibrillation. However the patient was under warfarin treatment, she developed a big left atrial big thrombus which was originated from left atrial appendage after she was suffered from AP. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Intra-cardiac burkitt's lymphoma mimicking acute pulmonary embolism

    International Nuclear Information System (INIS)

    Fatimi, S.; Seikh, S.; Zaman, S; Shafiq, M.

    2006-01-01

    Primary cardiac lymphoma is a rare clinical entity with poor prognosis and delayed diagnosis is often due to variable and non-specific clinical presentation. The case of an elderly male is reported with multiple co-morbidities, who had undergone a spinal laminectomy two weeks prior to presentation, later presented to the emergency room (E.R.) with acute chest pain, dyspnea and hypoxemia. A diagnosis of intracardiac thrombus was made, based on the clinical picture and echocardiography findings but per-operatively, he was found to have an extensive, non-resectable cardiac tumor. (author)

  10. Left ventricle myocardial border detection in three-dimensional intracardiac ultrasound images

    Science.gov (United States)

    Liang, Weidong; Kanani, Prapti; Allan, John; Kerber, Richard; McKay, Charles R.; Sonka, Milan

    1997-05-01

    We have previously reported an automated approach to detection of endocardial and epicardial borders in individual intracardiac ultrasound (ICUS) images. Here, we report the method's extension to 3D ICUS image data sets. Our method is based on fully automated detection of epicardial and endocardial borders inside a single interactively identified region of interest. BOrder detection is based on an optimal graph-searching approach that utilizes a priori knowledge about left ventricular (LV) anatomy and ultrasound imaging physics. Eight cadaveric pig hearts were used for validation. Two ICUS sequences were obtained from each heart, with a 10 MHz CVIS 10F catheter positioned in the LV across (1) the aortic valve and (2) the mitral valve. Performance of the 3D automated border detection method was assessed by comparing the observer- defined and computer-determined quantitative indices of LV volume and by border positioning errors. The 3D reconstruction of the lV was performed from the sequences of the detected epicardial and endocardial borders using shape- based interpolation and surface rendering.

  11. Using music structure to improve beat tracking

    Science.gov (United States)

    Dannenberg, Roger B.

    2005-09-01

    Beats are an important feature of most music. Beats are used in music information retrieval systems for genre classification, similarity search, and segmentation. However, beats can be difficult to identify, especially in music audio. Traditional beat trackers attempt to (1) match predicted beats to observations of likely beats, and (2) maintain a fairly steady tempo. A third criterion can be added: when repetitions of musical passages occur, the beats in the first repetition should align with the beats in all other repetitions. This third criterion improves beat tracking performance significantly. Repetitions of musical passages are discovered in audio data by searching for similar sequences of chroma vectors. Beats are ``tracked'' by first locating a sequence of likely beats in the music audio using high frequency energy as an indicator of beat likelihood. This beat sequence is then extended by searching forward and backward for more matching beats, allowing slight variations in tempo, and using a relaxation algorithm to optimize the proposed beat locations with respect to the three criteria. Other high-level music features may offer further improvements in beat identification.

  12. 4D MUSIC CMR: value-based imaging of neonates and infants with congenital heart disease.

    Science.gov (United States)

    Nguyen, Kim-Lien; Han, Fei; Zhou, Ziwu; Brunengraber, Daniel Z; Ayad, Ihab; Levi, Daniel S; Satou, Gary M; Reemtsen, Brian L; Hu, Peng; Finn, J Paul

    2017-04-03

    4D Multiphase Steady State Imaging with Contrast (MUSIC) acquires high-resolution volumetric images of the beating heart during uninterrupted ventilation. We aim to evaluate the diagnostic performance and clinical impact of 4D MUSIC in a cohort of neonates and infants with congenital heart disease (CHD). Forty consecutive neonates and infants with CHD (age range 2 days to 2 years, weight 1 to 13 kg) underwent 3.0 T CMR with ferumoxytol enhancement (FE) at a single institution. Independently, two readers graded the diagnostic image quality of intra-cardiac structures and related vascular segments on FE-MUSIC and breath held FE-CMRA images using a four-point scale. Correlation of the CMR findings with surgery and other imaging modalities was performed in all patients. Clinical impact was evaluated in consensus with referring surgeons and cardiologists. One point was given for each of five key outcome measures: 1) change in overall management, 2) change in surgical approach, 3) reduction in the need for diagnostic catheterization, 4) improved assessment of risk-to-benefit for planned intervention and discussion with parents, 5) accurate pre-procedural roadmap. All FE-CMR studies were completed successfully, safely and without adverse events. On a four-point scale, the average FE-MUSIC image quality scores were >3.5 for intra-cardiac structures and >3.0 for coronary arteries. Intra-cardiac morphology and vascular anatomy were well visualized with good interobserver agreement (r = 0.46). Correspondence between the findings on MUSIC, surgery, correlative imaging and autopsy was excellent. The average clinical impact score was 4.2 ± 0.9. In five patients with discordant findings on echo/MUSIC (n = 5) and catheter angiography/MUSIC (n = 1), findings on FE-MUSIC were shown to be accurate at autopsy (n = 1) and surgery (n = 4). The decision to undertake biventricular vs univentricular repair was amended in 2 patients based on FE-MUSIC findings

  13. "Cristal tachycardias": origin of right atrial tachycardias from the crista terminalis identified by intracardiac echocardiography.

    Science.gov (United States)

    Kalman, J M; Olgin, J E; Karch, M R; Hamdan, M; Lee, R J; Lesh, M D

    1998-02-01

    We sought to use intracardiac echocardiography (ICE) to identify the anatomic origin of focal right atrial tachycardias and to define their relation with the crista terminalis (CT). Previous studies using ICE during mapping of atrial flutter and inappropriate sinus tachycardia have demonstrated an important relation between endocardial anatomy and electrophysiologic events. Recent studies have suggested that right atrial tachycardias may also have a characteristic anatomic distribution. Twenty-three consecutive patients with 27 right atrial tachycardias were included in the study. ICE was used to facilitate activation mapping in relation to endocardial structures. A 20-pole catheter was positioned along the CT under ICE guidance. ICE was also used to assist in guiding detailed mapping with the ablation catheter in the right atrium. Of 27 focal right atrial tachycardias, 18 (67%, 95% confidence interval [CI] 46% to 83%) were on the CT (2 high medial, 8 high lateral, 6 mid and 2 low). ICE identified the location of the tip of the ablation catheter in immediate relation to the CT in all 18 cases. The 20-pole mapping catheter together with echocardiographic visualization of the CT provided a guide to the site of tachycardia origin along this structure. Radiofrequency ablation was successful in 26 (96%) of 27 (95% CI 81% to 100%) right atrial tachycardias. This study demonstrates that approximately two thirds of focal right atrial tachycardias occurring in the absence of structural heart disease will arise along the CT. Recognition of this common distribution may potentially facilitate mapping and ablation of these tachycardias.

  14. Low-Grade Endometrial Stromal Sarcoma with Intravenous and Intracardiac Extension: A Multidisciplinary Approach

    Directory of Open Access Journals (Sweden)

    Wataru Kudaka

    2016-01-01

    Full Text Available Background. A rare case of low-grade endometrial stromal sarcoma (LG-ESS extending to inferior vena cava (IVC and cardiac chambers. Case Report. A 40-year-old woman had IVC tumor, which was incidentally detected by abdominal ultrasonography during a routine medical checkup. CT scan revealed a tumor in IVC, right iliac and ovarian veins, which was derived from the uterus and extended into the right atrium and ventricle. The operation was performed, the heart and IVC were exposed, and cardiopulmonary bypass was initiated. A right atriotomy was performed, and the intracardiac mass was removed. Then the tumor in IVC and the right internal iliac vein were removed after longitudinal venotomies in the suprarenal and infrarenal vena cava, the right common iliac vein. Next the pelvis was explored. Tumors were found originating from the posterior wall of the uterus and continuing into both the right uterine and ovarian vein. The patient underwent total hysterectomy with bilateral salpingooophorectomy. Complete tumor resection was achieved. Histopathological analysis confirmed a diagnosis of LG-ESS. She showed no evidence of disease for 2 years and 3 months. Conclusions. Our case highlights the importance of a multidisciplinary approach in treating this rare cardiovascular pathological condition through preoperative assessment to final operation.

  15. Neonatal atrial flutter after insertion of an intracardiac umbilical venous catheter

    Directory of Open Access Journals (Sweden)

    Marcos Moura de Almeida

    2016-03-01

    Full Text Available Abstract Objective: To describe a case of neonatal atrial flutter after the insertion of an intracardiac umbilical venous catheter, reporting the clinical presentation and reviewing the literature on this subject. Case description: A late-preterm newborn, born at 35 weeks of gestational age to a diabetic mother and large for gestational age, with respiratory distress and rule-out sepsis, required an umbilical venous access. After the insertion of the umbilical venous catheter, the patient presented with tachycardia. Chest radiography showed that the catheter was placed in the position that corresponds to the left atrium, and traction was applied. The patient persisted with tachycardia, and an electrocardiogram showed atrial flutter. As the patient was hemodynamically unstable, electric cardioversion was successfully applied. Comments: The association between atrial arrhythmias and misplaced umbilical catheters has been described in the literature, but in this case, it is noteworthy that the patient was an infant born to a diabetic mother, which consists in another risk factor for heart arrhythmias. Isolated atrial flutter is a rare tachyarrhythmia in the neonatal period and its identification is essential to establish early treatment and prevent systemic complications and even death.

  16. Intracardiac Low-grade Sarcoma Following Treatment for Ewing Sarcoma.

    Science.gov (United States)

    Ortiz, Michael V; Magnan, Heather; Slotkin, Emily K; Ambati, Srikanth R; Chou, Alexander J; Wexler, Leonard H; Meyers, Paul A; Walsh, Michael F; Heaton, Todd; Girardi, Leonard N; Wolden, Suzanne L; Price, Anita P; Kennedy, Jennifer A; Zehir, Ahmet; Hameed, Meera; Berger, Michael F; Kentsis, Alex; Shukla, Neerav

    2017-11-01

    A 16-year-old male was diagnosed with Ewing sarcoma of the ribcage with pulmonary metastases. Six months after completion of scheduled therapy, he was found to have a new intracardiac mass, presumed recurrent Ewing sarcoma. EWSR1 fusion was not detected by droplet digital polymerase chain reaction from blood plasma. After no improvement with salvage chemotherapy, he underwent surgical resection that identified a low-grade spindle cell sarcoma. Despite the near-synchronous presentation of 2 unrelated sarcomas, extensive genomic analyses did not reveal any unifying somatic or germline mutations nor any apparent cancer predisposition. This case also highlights the potential role of utilizing plasma cell-free DNA for diagnosing tumors in locations where biopsy confers high morbidity.

  17. Intracardiac Askin Tumor: an Unusual Form of Presentation

    Directory of Open Access Journals (Sweden)

    R. Stiha

    2016-06-01

    Full Text Available Askin tumor is a rare peripheral neuro-ectodermal tumor from the Ewing sarcoma family, developing in the soft tissue of the chest wall. Presenting in childhood and adolescence, females are affected more commonly. An aggressive malignant tumor, its diagnosis is established by radiology, and confirmed by histology. We report the case of a 23 year-old patient, presented with 3 month history of swelling right side of chest, unexplained fever, dry cough, progressive shortness of breath and general malaise. Thoracic-abdominal-pelvic computed tomography revealed an Ewing's sarcoma with an intrathoracic component, confirmed by histology. Under chemotherapy, transthoracic echocardiography showed a soft tissue mass sitting in the left atrium with the same characteristics as the endothoracic mass. Askin tumor is a rare disease, an intracardiac location is even rarer.Thus, a systematic resting thransthoracic echocardiography must be realized whenever a diagnosis of Askin tumor is carried.

  18. A 13 μA analog signal processing IC for accurate recognition of multiple intra-cardiac signals.

    Science.gov (United States)

    Yan, Long; Pettine, Julia; Mitra, Srinjoy; Kim, Sunyoung; Jee, Dong-Woo; Kim, Hyejung; Osawa, Masato; Harada, Yasunari; Tamiya, Kosei; Van Hoof, Chris; Yazicioglu, Refet Firat

    2013-12-01

    A low-power analog signal processing IC is presented for the low-power heart rhythm analysis. The ASIC features 3 identical, but independent intra-ECG readout channels each equipping an analog QRS feature extractor for low-power consumption and fast diagnosis of the fatal case. A 16-level digitized sine-wave synthesizer together with a synchronous readout circuit can measure bio-impedance in the range of 0.1-4.4 kΩ with 33 mΩ(rms) resolution and higher than 97% accuracy. The proposed 25 mm² ASIC consumes only 13 μA from 2.2 V. It is a highly integrated solution offering all the functionality of acquiring multiple high quality intra-cardiac signals, requiring only a few limited numbers of external passives.

  19. Automatic Arrhythmia Beat Detection: Algorithm, System, and Implementation

    Directory of Open Access Journals (Sweden)

    Wisnu Jatmiko

    2016-08-01

    Full Text Available Cardiac disease is one of the major causes of death in the world. Early diagnose of the symptoms depends on abnormality on heart beat pattern, known as Arrhythmia. A novel fuzzy neuro generalized learning vector quantization for automatic Arrhythmia heart beat classification is proposed. The algorithm is an extension from theGLVQ algorithm that employs a fuzzy logic concept as the discriminant function in order to develop a robust algorithmand improve the classification performance. The algorithm is testedagainst MIT-BIH arrhythmia database to measure theperformance. Based on the experiment result, FN-GLVQ is able to increase the accuracy of GLVQ by a soft margin. As we intend to build a device with automated Arrhythmia detection,FN-GLVQ is then implemented into Field Gate Programmable Array to prototype the system into a real device.

  20. Binaural beats at high frequencies.

    Science.gov (United States)

    McFadden, D; Pasanen, E G

    1975-10-24

    Binaural beats have long been believed to be audible only at low frequencies, but an interaction reminiscent of a binaural beat can sometimes be heard when different two-tone complexes of high frequency are presented to the two ears. The primary requirement is that the frequency separation in the complex at one ear be slightly different from that in the other--that is, that there be a small interaural difference in the envelope periodicities. This finding is in accord with other recent demonstrations that the auditory system is not deaf to interaural time differences at high frequencies.

  1. 21 CFR 870.3470 - Intracardiac patch or pledget made of polypropylene, polyethylene terephthalate, or...

    Science.gov (United States)

    2010-04-01

    ... polypropylene, polyethylene terephthalate, or polytetrafluoroethylene. 870.3470 Section 870.3470 Food and Drugs... polypropylene, polyethylene terephthalate, or polytetrafluoroethylene. (a) Identification. An intracardiac patch or pledget made of polypropylene, polyethylene terephthalate, or polytetrafluoroethylene is a fabric...

  2. Intracardiac bone cement embolism as a complication of vertebroplasty: management strategy.

    Science.gov (United States)

    Hatzantonis, Catherine; Czyz, Marcin; Pyzik, Renata; Boszczyk, Bronek M

    2017-12-01

    Vertebroplasty carries multiple complications due to the leakage of polymethylmethacrylate (PMMA) into the venous system through the iliolumbar or epidural veins. The rate of venous cement complications may vary from 1 to 10 %, with cement extravasation into the venous system in 24 % of patients. Emboli may further migrate into the right heart chambers and pulmonary arteries. Patients may vary in presentation from asymptomatic or symptoms such as syncope to life-threatening complications. We present a case of a 57-year-old lady diagnosed with osteoporosis who underwent a staged antero-posterior fixation with PMMA vertebroplasty of progressive thoraco-lumbar kyphosis caused by osteoporotic fractures to T12, L1 and L2 vertebral bodies. Four weeks after the operation, the patient developed symptoms of left-sided chest pain, tachycardia and tachypnea. CT pulmonary angiogram (CTPA) found a high-density material within the right atrium, whilst ECHO demonstrated normal systolic function. The patient was commenced on enoxaparin at therapeutic dose of 1.5 mg/kg for 3 months and remained asymptomatic. Follow-up ECHO found no change to the heart function and no blood clot on the PMMA embolus. Factors influencing the decision about conservative treatment included symptoms, localisation of the embolus, as well as time lapse between vertebroplasty and clinical manifestation. Patients that are commonly asymptomatic can be treated conservatively. The management of choice is anticoagulation with low-molecular-weight heparin or warfarin until the foreign body epithelialises and ceases in becoming potentially thrombogenic. Symptomatic patients with thrombi in the right atrium are commonly managed via percutaneous retrieval, whilst those with RV involvement or perforation are commonly managed with surgical retrieval. Management of individual patients should be based on individual clinical circumstances. Patients presenting with intracardiac bone cement embolism related to spinal

  3. [Resonance hypothesis of heart rate variability origin].

    Science.gov (United States)

    Sheĭkh-Zade, Iu R; Mukhambetaliev, G Kh; Cherednik, I L

    2009-09-01

    A hypothesis is advanced of the heart rate variability being subjected to beat-to-beat regulation of cardiac cycle duration in order to ensure the resonance interaction between respiratory and own fluctuation of the arterial system volume for minimization of power expenses of cardiorespiratory system. Myogenic, parasympathetic and sympathetic machanisms of heart rate variability are described.

  4. Demonstrations of Beats as Moving Interference Patterns.

    Science.gov (United States)

    Stein, T. S.; Dishman, L. G.

    1982-01-01

    Describes a ripple tank demonstration that displays interference patterns responsible for producing beats and provides photographs of computer simulations of various beat interference patterns. Includes programs for the computer simulation and equations of constructive interference paths in beat interference patterns. (Author/SK)

  5. Average beta-beating from random errors

    CERN Document Server

    Tomas Garcia, Rogelio; Langner, Andy Sven; Malina, Lukas; Franchi, Andrea; CERN. Geneva. ATS Department

    2018-01-01

    The impact of random errors on average β-beating is studied via analytical derivations and simulations. A systematic positive β-beating is expected from random errors quadratic with the sources or, equivalently, with the rms β-beating. However, random errors do not have a systematic effect on the tune.

  6. A comparison of auditory evoked potentials to acoustic beats and to binaural beats.

    Science.gov (United States)

    Pratt, Hillel; Starr, Arnold; Michalewski, Henry J; Dimitrijevic, Andrew; Bleich, Naomi; Mittelman, Nomi

    2010-04-01

    The purpose of this study was to compare cortical brain responses evoked by amplitude modulated acoustic beats of 3 and 6 Hz in tones of 250 and 1000 Hz with those evoked by their binaural beats counterparts in unmodulated tones to indicate whether the cortical processes involved differ. Event-related potentials (ERPs) were recorded to 3- and 6-Hz acoustic and binaural beats in 2000 ms duration 250 and 1000 Hz tones presented with approximately 1 s intervals. Latency, amplitude and source current density estimates of ERP components to beats-evoked oscillations were determined and compared across beat types, beat frequencies and base (carrier) frequencies. All stimuli evoked tone-onset components followed by oscillations corresponding to the beat frequency, and a subsequent tone-offset complex. Beats-evoked oscillations were higher in amplitude in response to acoustic than to binaural beats, to 250 than to 1000 Hz base frequency and to 3 Hz than to 6 Hz beat frequency. Sources of the beats-evoked oscillations across all stimulus conditions located mostly to left temporal lobe areas. Differences between estimated sources of potentials to acoustic and binaural beats were not significant. The perceptions of binaural beats involve cortical activity that is not different than acoustic beats in distribution and in the effects of beat- and base frequency, indicating similar cortical processing. Copyright 2010 Elsevier B.V. All rights reserved.

  7. Beat-to-beat variability of cardiac action potential duration: underlying mechanism and clinical implications.

    Science.gov (United States)

    Nánási, Péter P; Magyar, János; Varró, András; Ördög, Balázs

    2017-10-01

    Beat-to-beat variability of cardiac action potential duration (short-term variability, SV) is a common feature of various cardiac preparations, including the human heart. Although it is believed to be one of the best arrhythmia predictors, the underlying mechanisms are not fully understood at present. The magnitude of SV is basically determined by the intensity of cell-to-cell coupling in multicellular preparations and by the duration of the action potential (APD). To compensate for the APD-dependent nature of SV, the concept of relative SV (RSV) has been introduced by normalizing the changes of SV to the concomitant changes in APD. RSV is reduced by I Ca , I Kr , and I Ks while increased by I Na , suggesting that ion currents involved in the negative feedback regulation of APD tend to keep RSV at a low level. RSV is also influenced by intracellular calcium concentration and tissue redox potential. The clinical implications of APD variability is discussed in detail.

  8. Warning Signs of Heart Failure

    Science.gov (United States)

    ... of High Cholesterol Cholesterol Tools & Resources Congenital Defects Children & Adults About Congenital Heart Defects The Impact of Congenital ... the loss in pumping capacity, the heart beats faster. This content was last reviewed May 2017. ... Learn more about Novartis Heart Failure Questions to Ask ...

  9. The use of intracardiac echocardiography during percutaneous pulmonary valve replacement.

    Science.gov (United States)

    Awad, Sawsan M; Masood, Syed Asif; Gonzalez, Ismael; Cao, Qi-Ling; Abdulla, Ra-id; Heitschmidt, Mary G; Hijazi, Ziyad M

    2015-01-01

    High-quality live imaging assessment of cardiac valves and cardiac anatomy is crucial for the success of catheter-based procedures. We present our experience using Intracardiac echocardiography (ICE) during transcatheter Percutaneous Pulmonary Valve replacement (tPVR).This is a retrospective study that included 35 patients who underwent tPVR between April 2008 and June 2012. Thirty-one of these patients had the procedure performed under continuous ICE guidance. Pre-procedure transthoracic echocardiography (TTE) was obtained in all patients. ICE was performed at baseline, during the procedure, and at the conclusion of the procedure. Comparisons between the pre-procedure TTE and baseline ICE data and between post-procedure ICE data and the following day TTE were performed. Total of 35 patients had tPVR during the above-mentioned time period. Twenty-one patients received the Edwards Sapien valve and 14 patients had the Melody valve. Thirty-one patients had the procedure performed under continuous ICE guidance. The mean Pre-TTE peak gradient (PG) and Pre-ICE-PG were 45.5 ± 20 vs 33 ± 13 mmHg (p TTE mean gradient (MG) and Pre-ICE-MG were 27.7 ± 13 vs 21 ± 18 mmHg (p TTE- PG and Post-ICE-PG were 24.3 ± 11 vs 15.3 ± 7 mmHg (p TTE-MG and Post-ICE-MG were 14.2 ± 7 vs 8.4 ± 4 mmHg (p TTE gradient at baseline and after valve placement. For the degree of pulmonary regurgitation, there was no significant difference between TTE and ICE. ICE is an important modality to guide tPVR in patients with dysfunctional homograft valve between the right ventricle and pulmonary artery and should be used to assess valve function before, during and immediately after the procedure.

  10. Auditory driving of the autonomic nervous system: Listening to theta-frequency binaural beats post-exercise increases parasympathetic activation and sympathetic withdrawal

    OpenAIRE

    Patrick eMcConnell; Patrick eMcConnell; Brett eFroeliger; Eric L. Garland; Jeffrey C. Ives; Gary A. Sforzo

    2014-01-01

    Binaural beats are an auditory illusion perceived when two or more pure tones of similar frequencies are presented dichotically through stereo headphones. Although this phenomenon is thought to facilitate state changes (e.g., relaxation), few empirical studies have reported on whether binaural beats produce changes in autonomic arousal. Therefore, the present study investigated the effects of binaural beating on autonomic dynamics (heart-rate variability (HRV)) during post-exercise relaxation...

  11. Auditory driving of the autonomic nervous system: Listening to theta-frequency binaural beats post-exercise increases parasympathetic activation and sympathetic withdrawal

    OpenAIRE

    McConnell, Patrick A.; Froeliger, Brett; Garland, Eric L.; Ives, Jeffrey C.; Sforzo, Gary A.

    2014-01-01

    Binaural beats are an auditory illusion perceived when two or more pure tones of similar frequencies are presented dichotically through stereo headphones. Although this phenomenon is thought to facilitate state changes (e.g., relaxation), few empirical studies have reported on whether binaural beats produce changes in autonomic arousal. Therefore, the present study investigated the effects of binaural beating on autonomic dynamics [heart rate variability (HRV)] during post-exercise relaxation...

  12. Electrical brain responses to beat irregularities in two cases of beat deafness

    NARCIS (Netherlands)

    Mathias, B.; Lidji, P.; Honing, H.; Palmer, C.; Peretz, I.

    2016-01-01

    Beat deafness, a recently documented form of congenital amusia, provides a unique window into functional specialization of neural circuitry for the processing of musical stimuli: Beat-deaf individuals exhibit deficits that are specific to the detection of a regular beat in music and the ability to

  13. Intracardiac tumor: A risk factor for stroke in the young –A case report

    African Journals Online (AJOL)

    Intracardiac mass should be considered a possible risk factor for ischemic stroke in young adult, especially in the absence of other risk factors such as connective tissue disorders, HIV/AIDS, hemoglobinopathy or use of recreational drugs. High index of suspicion is required in order not to overlook such source of emboli.

  14. Intracardiac impedance response during acute AF internal cardioversion using novel rectilinear and capacitor-discharge waveforms.

    Science.gov (United States)

    Rababah, A S; Walsh, S J; Manoharan, G; Walsh, P R; Escalona, O J

    2016-07-01

    Intracardiac impedance (ICI) is a major determinant of success during internal cardioversion of atrial fibrillation (AF). However, there have been few studies that have examined the dynamic behaviour of atrial impedance during internal cardioversion in relation to clinical outcome. In this study, voltage and current waveforms captured during internal cardioversion of acute AF in ovine models using novel radiofrequency (RF) generated low-tilt rectilinear and conventional capacitor-discharge based shock waveforms were retrospectively analysed using a digital signal processing algorithm to investigate the dynamic behaviour of atrial impedance during cardioversion. The algorithm was specifically designed to facilitate the simultaneous analysis of multiple impedance parameters, including: mean intracardiac impedance (Z M), intracardiac impedance variance (ICIV) and impedance amplitude spectrum area (IAMSA) for each cardioversion event. A significant reduction in ICI was observed when comparing two successive shocks of increasing energy where cardioversion outcome was successful. In addition, ICIV and IAMSA variables were found to inversely correlate to the magnitude of energy delivered; with a stronger correlation found to the former parameter. In conclusion, ICIV and IAMSA have been evidenced as two key dynamic intracardiac impedance variables that may prove useful in better understanding of the cardioversion process and that could potentially act as prognostic markers with respect to clinical outcome.

  15. Dichotic beats of mistuned consonances.

    Science.gov (United States)

    Feeney, M P

    1997-10-01

    The beats of mistuned consonances (BMCs) result from the presentation of two sinusoids at frequencies slightly mistuned from a ratio of small integers. Several studies have suggested that the source of dichotic BMCs is an interaction within a binaural critical band. In one case the mechanism has been explained as an aural harmonic of the low-frequency tone (f1) creating binaural beats with the high-frequency tone (f2). The other explanation involves a binaural cross correlation between the excitation pattern of f1 and the contralateral f2--occurring within the binaural critical band centered at f2. This study examined the detection of dichotic BMCs for the octave and fifth. In one experiment with the octave, narrow-band noise centered at f2 was presented to one ear along with f1. The other ear was presented with f2. The noise was used to prevent interactions in the binaural critical band centered at f2. Dichotic BMCs were still detected under these conditions, suggesting that binaural interaction within a critical band does not explain the effect. Localization effects were also observed under this masking condition for phase reversals of tuned dichotic octave stimuli. These findings suggest a new theory of dichotic BMCs as a between-channel phase effect. The modified weighted-image model of localization [Stern and Trahiotis, in Auditory Physiology and Perception, edited by Y. Cazals, L. Demany, and K. Horner (Pergamon, Oxford, 1992), pp. 547-554] was used to provide an explanation of the between-channel mechanism.

  16. Ventricular beat detection in single channel electrocardiograms.

    Science.gov (United States)

    Dotsinsky, Ivan A; Stoyanov, Todor V

    2004-01-29

    Detection of QRS complexes and other types of ventricular beats is a basic component of ECG analysis. Many algorithms have been proposed and used because of the waves' shape diversity. Detection in a single channel ECG is important for several applications, such as in defibrillators and specialized monitors. The developed heuristic algorithm for ventricular beat detection includes two main criteria. The first of them is based on steep edges and sharp peaks evaluation and classifies normal QRS complexes in real time. The second criterion identifies ectopic beats by occurrence of biphasic wave. It is modified to work with a delay of one RR interval in case of long RR intervals. Other algorithm branches classify already detected QRS complexes as ectopic beats if a set of wave parameters is encountered or the ratio of latest two RR intervals RRi-1/RRi is less than 1:2.5. The algorithm was tested with the AHA and MIT-BIH databases. A sensitivity of 99.04% and a specificity of 99.62% were obtained in detection of 542014 beats. The algorithm copes successfully with different complicated cases of single channel ventricular beat detection. It is aimed to simulate to some extent the experience of the cardiologist, rather than to rely on mathematical approaches adopted from the theory of signal analysis. The algorithm is open to improvement, especially in the part concerning the discrimination between normal QRS complexes and ectopic beats.

  17. Electrical Brain Responses to Beat Irregularities in Two Cases of Beat Deafness

    Science.gov (United States)

    Mathias, Brian; Lidji, Pascale; Honing, Henkjan; Palmer, Caroline; Peretz, Isabelle

    2016-01-01

    Beat deafness, a recently documented form of congenital amusia, provides a unique window into functional specialization of neural circuitry for the processing of musical stimuli: Beat-deaf individuals exhibit deficits that are specific to the detection of a regular beat in music and the ability to move along with a beat. Studies on the neural underpinnings of beat processing in the general population suggest that the auditory system is capable of pre-attentively generating a predictive model of upcoming sounds in a rhythmic pattern, subserved largely within auditory cortex and reflected in mismatch negativity (MMN) and P3 event-related potential (ERP) components. The current study examined these neural correlates of beat perception in two beat-deaf individuals, Mathieu and Marjorie, and a group of control participants under conditions in which auditory stimuli were either attended or ignored. Compared to control participants, Mathieu demonstrated reduced behavioral sensitivity to beat omissions in metrical patterns, and Marjorie showed a bias to identify irregular patterns as regular. ERP responses to beat omissions reveal an intact pre-attentive system for processing beat irregularities in cases of beat deafness, reflected in the MMN component, and provide partial support for abnormalities in later cognitive stages of beat processing, reflected in an unreliable P3b component exhibited by Mathieu—but not Marjorie—compared to control participants. P3 abnormalities observed in the current study resemble P3 abnormalities exhibited by individuals with pitch-based amusia, and are consistent with attention or auditory-motor coupling accounts of deficits in beat perception. PMID:26941591

  18. Electrical brain responses to beat irregularities in two cases of beat deafness

    Directory of Open Access Journals (Sweden)

    Brian eMathias

    2016-02-01

    Full Text Available Beat deafness, a recently documented form of congenital amusia, provides a unique window into functional specialization of neural circuitry for the processing of musical stimuli: Beat-deaf individuals exhibit deficits that are specific to the detection of a regular beat in music and the ability to move along with a beat. Studies on the neural underpinnings of beat processing in the general population suggest that the auditory system is capable of pre-attentively generating a predictive model of upcoming sounds in a rhythmic pattern, subserved largely within auditory cortex and reflected in mismatch negativity (MMN and P3 event-related potential (ERP components. The current study examined these neural correlates of beat perception in two beat-deaf individuals, Mathieu and Marjorie, and a group of control participants under conditions in which auditory stimuli were either attended or ignored. Compared to control participants, Mathieu demonstrated reduced behavioral sensitivity to beat omissions in metrical patterns, and Marjorie showed a bias to identify irregular patterns as regular. ERP responses to beat omissions reveal an intact pre-attentive system for processing beat irregularities in cases of beat deafness, reflected in the MMN component, and provide partial support for abnormalities in later cognitive stages of beat processing, reflected in an unreliable P3b component exhibited by Mathieu – but not Marjorie – compared to control participants. P3 abnormalities observed in the current study resemble P3 abnormalities exhibited by individuals with pitch-based amusia, and are consistent with attention or auditory-motor coupling accounts of deficits in beat perception.

  19. Case Report: Rare Intracardiac Aneurysms seen in Jos, Nigeria: A ...

    African Journals Online (AJOL)

    One was a ruptured sinus of Valsalva aneurysm dissecting the interventricular septum and the other ventricular septal defect aneurysm involving the tricuspid valve. Conclusion: Some congenital heart diseases present late. Increased availability of echocardiography and skilled personnel should lead to early diagnosis ...

  20. Features of The Heart Remodeling in Patients with Chronic Obstructive Pulmonary Diseases, Combined with Coronary Heart Diseases

    Directory of Open Access Journals (Sweden)

    A.Yu. Ryabova

    2009-09-01

    Full Text Available The characteristics of heart remodeling in patients with chronic obstructive pulmonary diseases ( COPD, associated with coronary heart diseases (CHD were examined. The changes of structural and functional state of myocardium, intracardiac relationships with associated pathology were under study. The role of blood inflammatory cytokines (IL-6, IL-8, TNF-a and the level of cell adhesion molecules (ICAM-1, VCAM-1 in exacerbating myocardial dysfunction was clarified.

  1. Binaural beats and frequency-coding.

    Science.gov (United States)

    Fritze, W; Köhler, W

    1986-01-01

    Binaural beats were studied before and during a situation of temporary threshold shift, and no frequency shift could be found. In contrast, subjective binaural frequency comparison revealed a distinct shift. These findings demonstrate the two known modes of perception.

  2. Moving Sources: Doppler Beats and Mach Cones

    Science.gov (United States)

    Gluck, Paul

    2005-09-01

    This paper describes two experiments involving moving sources. The first one is a class activity for observing beats in a Doppler setup; the second one describes how to observe the transition from "subsonic" to "supersonic" waves in a ripple tank.

  3. Image Quality, Overall Evaluability, and Effective Radiation Dose of Coronary Computed Tomography Angiography With Prospective Electrocardiographic Triggering Plus Intracycle Motion Correction Algorithm in Patients With a Heart Rate Over 65 Beats Per Minute.

    Science.gov (United States)

    Pontone, Gianluca; Muscogiuri, Giuseppe; Baggiano, Andrea; Andreini, Daniele; Guaricci, Andrea I; Guglielmo, Marco; Fazzari, Fabio; Mushtaq, Saima; Conte, Edoardo; Annoni, Andrea; Formenti, Alberto; Mancini, Elisabetta; Verdecchia, Massimo; Fusini, Laura; Bonfanti, Lorenzo; Consiglio, Elisa; Rabbat, Mark G; Bartorelli, Antonio L; Pepi, Mauro

    2018-01-16

    Recently, a new intracycle motion correction algorithm (MCA) was introduced to reduce motion artifacts from heart rate (HR) in coronary computed tomography angiography (cCTA). The aim of the study was to evaluate the image quality, overall evaluability, and effective radiation dose (ED) of cCTA with prospective electrocardiographic (ECG) triggering plus MCA as compared with standard protocol with retrospective ECG triggering in patients with HR≥65 bpm. One hundred consecutive patients (67±10 y) scheduled for cCTA with 65Ethics Committee and a written informed consent was obtained from all patients. Image noise, signal to noise ratio, contrast to noise ratio, Likert image quality score (score 1, nondiagnostic; score 2, adequate; score 3, good; score 4, excellent), overall image evaluability, and ED were measured and compared between the 2 groups. Both vessel-based and patient-based analyses were evaluated. Student test or Wilcoxon test were used to evaluate differences of continuous variables, whereas the χ test was used to study differences with regard to categorical data. A P-value <0.05 was considered statistically significant. cCTA was successfully performed in all patients. In a segment-based model, group 1 compared with group 2 showed a lower rate of overall artifacts (67% vs. 83%; P<0.001) and motion artifacts (49% vs. 66%; P<0.001), resulting in a better Likert image quality score (2.83±1.03 vs. 2.37±1.02; P<0.01) and overall evaluability (85% vs. 75%; P<0.01). Group 1 showed a lower ED as compared with group 2 (3.1±1.9 vs. 11.9±3.3 mSv; P<0.01). MCA and cCTA with prospective ECG-triggering acquisition in patients with high HR improves image quality and overall evaluability compared with cCTA with standard retrospective ECG triggering.

  4. Theory of beat-wave current drive

    Energy Technology Data Exchange (ETDEWEB)

    Mendonca, J.T.; Galvao, R.M.O.

    1986-06-01

    The beat-wave scheme for current drive is studied in the frame of plasma weak-turbulence theory. The value of the driven current is limited by a quasi-linear diffusion mechanism. The one-dimensional problem, corresponding to the resonant excitation of electron plasma oscillations by two beating electro-magnetic beams is discussed in detail. The results may be relevant to the continuous operation of tokamak discharges.

  5. Alterações hemodinâmicas devido ao uso de estabilizadores em revascularização do miocárdio: estudo experimental Hemodynamic disorders related to beating heart surgery using cardiac stabilizers: experimental study

    Directory of Open Access Journals (Sweden)

    Pedro Paulo Martins de Oliveira

    2007-12-01

    -pump coronary artery bypass graft surgeries by means of both a suction device "Octopus" and a compression device (Speroni. METHODS: Ten swine underwent median sternotomy. Monitoring of ECG, continuous cardiac output, mean arterial pressure, mean pulmonary artery pressure, mean right and left atrial pressures, and right and left ventricular diastolic pressure were performed. Stroke volume and systemic vascular resistance were calculated. Both stabilizers were studied placed on three vessels: anterior interventricular branch, posterior interventricular branch, and marginal branch of the circumflex branch. Each animal was randomly designed to application regarding the type of stabilizer and the target artery. The measurements were carried out 5 minutes before and after the stabilizer application. RESULTS: In the anterior interventricular branch changes have occurred only with the compression device, thus reducing cardiac output, stroke volume, and mean arterial pressure, but increasing the systemic vascular resistance. In the posterior interventricular branch changes have occurred with the compression device (Speroni, reducing cardiac output and stroke volume, but increasing the heart rate. With the suction device (octopus there was an increase of both heart rate and systemic vascular resistance, but a decrease in stroke volume. In the marginal branch of the circumflex branch there was a decrease of cardiac output, stroke volume, and mean arterial pressure with both stabilizers. Also, there was a decrease in the mean pulmonary artery pressure and an increase in the mean right atrial pressure with the compression device (Speroni. CONCLUSION: Both stabilizers have caused hemodynamic changes. The compression device (Speroni is more associated with changes than the suction device (Octopus.

  6. Beat characteristics and beat maps of the King Seong-deok Divine Bell

    Science.gov (United States)

    Kim, Seock-Hyun; Lee, Chi-Wook; Lee, Jang-Moo

    2005-03-01

    King Seong-deok Divine Bell is the second oldest bell in Korea. The bell is considered to have the best sound quality among Korean bells. The beat phenomenon is one of the most important characteristics for the sound of the King Seong-deok Divine Bell. In this study, the relationships between the modal parameters and the peculiar beat phenomena of the bell are investigated. It is theoretically proved from the beat characteristics that the sound might indeed be heard differently depending on the listening positions. The beat map method is introduced to visualize the beat distribution properties. It is shown that the beat maps can be drawn with a theoretical model based on the modal data of the bell. Using the beat maps of the King Seong-deok Divine Bell, it is investigated why clear and unclear beats, large and small amplitudes of the vibrations are repeated periodically along the circumference of the bell. Furthermore, the effect of the striking position on the beat distribution property is examined systematically.

  7. Cartan frames for heart wall fiber motion

    NARCIS (Netherlands)

    Samari, Babak; Aumentado-Armstrong, Tristan; Strijkers, Gustav J.; Froeling, Martijn; Siddiqi, Kaleem

    2017-01-01

    Current understanding of heart wall fiber geometry is based on ex vivo static data obtained through diffusion imaging or histology. Thus, little is known about the manner in which fibers rotate as the heart beats. Yet, the geometric organization of moving fibers in the heart wall is key to its

  8. The impact of binaural beats on creativity.

    Science.gov (United States)

    Reedijk, Susan A; Bolders, Anne; Hommel, Bernhard

    2013-01-01

    Human creativity relies on a multitude of cognitive processes, some of which are influenced by the neurotransmitter dopamine. This suggests that creativity could be enhanced by interventions that either modulate the production or transmission of dopamine directly, or affect dopamine-driven processes. In the current study we hypothesized that creativity can be influenced by means of binaural beats, an auditory illusion that is considered a form of cognitive entrainment that operates through stimulating neuronal phase locking. We aimed to investigate whether binaural beats affect creative performance at all, whether they affect divergent thinking, convergent thinking, or both, and whether possible effects may be mediated by the individual striatal dopamine level. Binaural beats were presented at alpha and gamma frequency. Participants completed a divergent and a convergent thinking task to assess two important functions of creativity, and filled out the Positive And Negative Affect Scale-mood State questionnaire (PANAS-S) and an affect grid to measure current mood. Dopamine levels in the striatum were estimated using spontaneous eye blink rates (EBRs). Results showed that binaural beats, regardless of the presented frequency, can affect divergent but not convergent thinking. Individuals with low EBRs mostly benefitted from alpha binaural beat stimulation, while individuals with high EBRs were unaffected or even impaired by both alpha and gamma binaural beats. This suggests that binaural beats, and possibly other forms of cognitive entrainment, are not suited for a one-size-fits-all approach, and that individual cognitive-control systems need to be taken into account when studying cognitive enhancement methods.

  9. The impact of binaural beats on creativity

    Directory of Open Access Journals (Sweden)

    Susan A. Reedijk

    2013-11-01

    Full Text Available Human creativity relies on a multitude of cognitive processes, some of which are influenced by the neurotransmitter dopamine. This suggests that creativity could be enhanced by interventions that either modulate the production or transmission of dopamine directly, or affect dopamine-driven processes. In the current study we hypothesized that creativity can be influenced by means of binaural beats, an auditory illusion that is considered a form of cognitive entrainment that operates through stimulating neuronal phase locking. We aimed to investigate whether binaural beats affect creative performance at all, whether they affect divergent thinking, convergent thinking, or both, and whether possible effects may be mediated by the individual striatal dopamine level. Binaural beats were presented at alpha and gamma frequency. Participants completed a divergent and a convergent thinking task to assess two important functions of creativity, and filled out the Positive And Negative Affect Scale – mood State questionnaire (PANAS-S and affect grid to measure current mood. Dopamine levels in the striatum were estimated using spontaneous eye blink rates (EBRs. Results showed that binaural beats, regardless of the presented frequency, can affect divergent but not convergent thinking. Individuals with low EBRs mostly benefitted from alpha binaural beat stimulation, while individuals with high EBR were unaffected or even impaired by both alpha and gamma binaural beats. This suggests that binaural beats, and possibly other forms of cognitive entrainment, are not suited for a one-size-fits-all approach, and that individual cognitive-control systems need to be taken into account when studying cognitive enhancement methods.

  10. High beat-to-beat blood pressure variability in atrial fibrillation compared to sinus rhythm.

    Science.gov (United States)

    Olbers, Joakim; Gille, Adam; Ljungman, Petter; Rosenqvist, Mårten; Östergren, Jan; Witt, Nils

    2018-02-07

    Atrial fibrillation (AF) is associated with an increased risk for cardiovascular morbidity and mortality, not entirely explained by thromboembolism. The underlying mechanisms for this association are largely unknown. Similarly, high blood pressure (BP) increases the risk for cardiovascular events. Despite this the interplay between AF and BP is insufficiently studied. The purpose of this study was to examine and quantify the beat-to-beat blood pressure variability in patients with AF in comparison to a control group of patients with sinus rhythm. We studied 33 patients - 21 in atrial fibrillation and 12 in sinus rhythm - undergoing routine coronary angiography. Invasive blood pressure was recorded at three locations: radial artery, brachial artery and ascending aorta. Blood pressure variability, defined as average beat-to-beat blood pressure difference, was calculated for systolic and diastolic blood pressure at each site. We observed a significant difference (p blood pressure variability between the atrial fibrillation and sinus rhythm groups at all locations. Systolic blood pressure variability roughly doubled in the atrial fibrillation group compared to the sinus rhythm group (4.9 and 2.4 mmHg respectively). Diastolic beat-to-beat blood pressure variability was approximately 6 times as high in the atrial fibrillation group compared to the sinus rhythm group (7.5 and 1.2 mmHg respectively). No significant difference in blood pressure variability was seen between measurement locations. Beat-to-beat blood pressure variability in patients with atrial fibrillation was substantially higher than in patients with sinus rhythm. Hemodynamic effects of this beat-to-beat variation in blood pressure may negatively affect vascular structure and function, which may contribute to the increased cardiovascular morbidity and mortality seen in patients with atrial fibrillation.

  11. Peak heart rates at extreme altitudes

    DEFF Research Database (Denmark)

    Lundby, C; Van Hall, Gerrit

    2001-01-01

    We have measured maximal heart rate during a graded maximal bicycle exercise test to exhaustion in five healthy climbers before and during an expedition to Mt. Everest. Maximal heart rates at sea level were 186 (177-204) beats/min(-1) at sea level and 170 (169-182) beats/min(-1) with acute hypoxia....... After 1, 4 and 6 weeks of acclimatization to 5400 m, maximal heart rates were 155 (135-182), 158 (144-182), and 155 (140-183) beats/min(-1), respectively. Heart rates of two of the climbers were measured during their attempt to reach the summit of Mt. Everest without the use of supplemental oxygen....... The peak heart rates at 8,750 m for the two climbers were 142 and 144 beats/min(-1), which were similar to their maximal heart rates during exhaustive bicycle exercise at 5,400 m, the values being 144 and 148 beats/min(-1), respectively. The peak heart rates at 8,750 m are in agreement with other field...

  12. Acoustical sensing of cardiomyocyte cluster beating

    International Nuclear Information System (INIS)

    Tymchenko, Nina; Kunze, Angelika; Dahlenborg, Kerstin; Svedhem, Sofia; Steel, Daniella

    2013-01-01

    Highlights: •An example of the application of QCM-D to live cell studies. •Detection of human pluripotent stem cell-derived cardiomyocyte cluster beating. •Clusters were studied in a thin liquid film and in a large liquid volume. •The QCM-D beating profile provides an individual fingerprint of the hPS-CMCs. -- Abstract: Spontaneously beating human pluripotent stem cell-derived cardiomyocytes clusters (CMCs) represent an excellent in vitro tool for studies of human cardiomyocyte function and for pharmacological cardiac safety assessment. Such testing typically requires highly trained operators, precision plating, or large cell quantities, and there is a demand for real-time, label-free monitoring of small cell quantities, especially rare cells and tissue-like structures. Array formats based on sensing of electrical or optical properties of cells are being developed and in use by the pharmaceutical industry. A potential alternative to these techniques is represented by the quartz crystal microbalance with dissipation monitoring (QCM-D) technique, which is an acoustic surface sensitive technique that measures changes in mass and viscoelastic properties close to the sensor surface (from nm to μm). There is an increasing number of studies where QCM-D has successfully been applied to monitor properties of cells and cellular processes. In the present study, we show that spontaneous beating of CMCs on QCM-D sensors can be clearly detected, both in the frequency and the dissipation signals. Beating rates in the range of 66–168 bpm for CMCs were detected and confirmed by simultaneous light microscopy. The QCM-D beating profile was found to provide individual fingerprints of the hPS-CMCs. The presented results point towards acoustical assays for evaluation cardiotoxicity

  13. Acoustical sensing of cardiomyocyte cluster beating

    Energy Technology Data Exchange (ETDEWEB)

    Tymchenko, Nina; Kunze, Angelika [Dept. of Applied Physics, Chalmers University of Technology, 412 96 Göteborg (Sweden); Dahlenborg, Kerstin [Cellectis, 413 46 Göteborg (Sweden); Svedhem, Sofia, E-mail: sofia.svedhem@chalmers.se [Dept. of Applied Physics, Chalmers University of Technology, 412 96 Göteborg (Sweden); Steel, Daniella [Cellectis, 413 46 Göteborg (Sweden)

    2013-06-14

    Highlights: •An example of the application of QCM-D to live cell studies. •Detection of human pluripotent stem cell-derived cardiomyocyte cluster beating. •Clusters were studied in a thin liquid film and in a large liquid volume. •The QCM-D beating profile provides an individual fingerprint of the hPS-CMCs. -- Abstract: Spontaneously beating human pluripotent stem cell-derived cardiomyocytes clusters (CMCs) represent an excellent in vitro tool for studies of human cardiomyocyte function and for pharmacological cardiac safety assessment. Such testing typically requires highly trained operators, precision plating, or large cell quantities, and there is a demand for real-time, label-free monitoring of small cell quantities, especially rare cells and tissue-like structures. Array formats based on sensing of electrical or optical properties of cells are being developed and in use by the pharmaceutical industry. A potential alternative to these techniques is represented by the quartz crystal microbalance with dissipation monitoring (QCM-D) technique, which is an acoustic surface sensitive technique that measures changes in mass and viscoelastic properties close to the sensor surface (from nm to μm). There is an increasing number of studies where QCM-D has successfully been applied to monitor properties of cells and cellular processes. In the present study, we show that spontaneous beating of CMCs on QCM-D sensors can be clearly detected, both in the frequency and the dissipation signals. Beating rates in the range of 66–168 bpm for CMCs were detected and confirmed by simultaneous light microscopy. The QCM-D beating profile was found to provide individual fingerprints of the hPS-CMCs. The presented results point towards acoustical assays for evaluation cardiotoxicity.

  14. The Nature of Ventricular Ectopic Beats in Chronic Ischaemic Heart ...

    African Journals Online (AJOL)

    1974-05-25

    May 25, 1974 ... The study was conducted on 80 males and 4 females who had been hospitalised at I Military Hospital with the clinical picture of acute myocardial infarction, subs- tantiated by serial electrocardiographic and serum en- zyme changes. After discharge from hospital the patients were periodically evaluated at ...

  15. The new heart of the PS is beating strongly

    CERN Multimedia

    Corinne Pralavorio

    2011-01-01

    The PS has resumed operation with a brand new electrical power system called POPS; this enormous system comprising power electronics and capacitors is crucial because if it broke down practically no particles would be able to circulate at CERN. As soon as it started, POPS passed all the tests with flying colours and is now pulsing at full power.   The new PS power system is made up of 6 containers, each with 60 tonnes of capacitors and 8 power converters. The date 11/02/11 will always be remembered with affection by the engineers in the Electrical Power Converters Group. At 11:11 in the morning (no joke), the first beams powered by the new system began to circulate in the PS. The cutely-named POPS (POwer for PS) took over from the old rotating machine that had been working since 1968. From now on it will be POPS that supplies the PS main magnets with the electrical pulses needed to accelerate the beams for the LHC and all CERN's other facilities. The system is crucial as the PS is one of the lyn...

  16. Functional distribution of coronary vascular volume in beating goat hearts

    NARCIS (Netherlands)

    van der Ploeg, C. P.; Dankelman, J.; Spaan, J. A.

    1993-01-01

    With use of hemoglobin-bound O2 as an endogenous tracer, intramyocardial blood volume distribution between vessels involved in O2 exchange and more distal vessels was estimated. In nine anesthetized open-chest goats, the left main coronary artery was cannulated and perfused at a constant flow.

  17. Truthfulness in transplantation: non-heart-beating organ donation

    Directory of Open Access Journals (Sweden)

    Potts Michael

    2007-08-01

    Full Text Available Abstract The current practice of organ transplantation has been criticized on several fronts. The philosophical and scientific foundations for brain death criteria have been crumbling. In addition, donation after cardiac death, or non-heartbeating-organ donation (NHBD has been attacked on grounds that it mistreats the dying patient and uses that patient only as a means to an end for someone else's benefit. Verheijde, Rady, and McGregor attack the deception involved in NHBD, arguing that the donors are not dead and that potential donors and their families should be told that is the case. Thus, they propose abandoning the dead donor rule and allowing NHBD with strict rules concerning adequate informed consent. Such honesty about NHBD should be welcomed. However, NHBD violates a fundamental end of medicine, nonmaleficience, "do no harm." Physicians should not be harming or killing patients, even if it is for the benefit of others. Thus, although Verheijde and his colleages should be congratulated for calling for truthfulness about NHBD, they do not go far enough and call for an elimination of such an unethical procedure from the practice of medicine.

  18. Probabilistic Model-Based Approach for Heart Beat Detection

    OpenAIRE

    Chen, Hugh; Erol, Yusuf; Shen, Eric; Russell, Stuart

    2015-01-01

    Nowadays, hospitals are ubiquitous and integral to modern society. Patients flow in and out of a veritable whirlwind of paperwork, consultations, and potential inpatient admissions, through an abstracted system that is not without flaws. One of the biggest flaws in the medical system is perhaps an unexpected one: the patient alarm system. One longitudinal study reported an 88.8% rate of false alarms, with other studies reporting numbers of similar magnitudes. These false alarm rates lead to a...

  19. Behind the scenes of GS: CERN’s beating heart

    CERN Multimedia

    Antonella Del Rosso

    2014-01-01

    Founded at the same time as CERN, the library has followed, and sometimes even moved ahead of, the changes in the Organization. Today, far from being a simple book depository, the Scientific Information Service (SIS) that manages CERN's library is increasingly digitising its material and investing in innovative projects, such as Open Access.   Ever since it was set up in Building 52 on 1 September 1957, the library has played a vital role in the Organization.  “Our only official task is to provide a complete list of the publications by CERN researchers, but, in fact, this place is the memory bank of the whole Laboratory,” emphasises Tullio Basaglia, head of the Library Section within SIS.  “The role of the library and archives is to preserve, document and disseminate the knowledge produced at CERN.” Sixty years after its creation, the library today contains 90,000 books, two thirds of which are available in a digital ...

  20. Real-time integration of 2D intracardiac echocardiography and 3D electroanatomical mapping to guide ventricular tachycardia ablation.

    Science.gov (United States)

    Khaykin, Yaariv; Skanes, Allan; Whaley, Bonnie; Hill, Carol; Beardsall, Marianne; Seabrook, Catherine; Wulffhart, Zaev; Oosthuizen, Richard; Gula, Lorne; Verma, Atul

    2008-10-01

    Ablation of left ventricular tachycardia (LV VT) involves point-by-point reconstruction of the three-dimensional (3D) virtual anatomy. It is time consuming and requires substantial fluoroscopy exposure. Two-dimensional (2D) intracardiac echocardiography (ICE) affords real-time imaging of the cardiac structures. This study sought to evaluate a mapping system integrating ICE with 3D mapping to guide VT ablation. Seventeen patients (16 men, 62 +/- 11 years, LV ejection fraction 40% +/- 15%) had ablation of nonidiopathic VT guided using a system integrating 3D mapping and ICE. ICE probe with a location sensor tracked by the mapping system was positioned in the right heart. Endocardial contours traced on gated images of the LV were used to generate a registered 3D map. Regional wall motion abnormalities (WMA) were tagged. 3D maps were created in 26 +/- 8 min, before entering the LV and without fluoroscopy. Maps were built from 23 +/- 7 contours. Regional WMA corresponded to low bipolar voltage (ICE was 172 +/- 119 cm(3) versus 164 +/- 112 cm(3) for the point-by-point maps (P = .5). Scar area by ICE was 33 +/- 32 cm(2) versus 36 +/- 33 cm(2) for voltage mapping (P = .4). At 5 +/- 4 months, 12 patients (71%) were free of VT. A system combining 2D ICE and 3D mapping can reconstruct a 3D shell of the LV, including a substrate map based on regional WMA without the need to enter the LV. VT ablation guided using this approach is safe and effective.

  1. Clinical evaluation of the use of an intracardiac electrocardiogram to guide the tip positioning of peripherally inserted central catheters.

    Science.gov (United States)

    Zhao, Ruiyi; Chen, Chunfang; Jin, Jingfen; Sharma, Komal; Jiang, Nan; Shentu, Yingqin; Wang, Xingang

    2016-06-01

    The use of peripherally inserted central catheters (PICCs) provides important central venous accesses for clinical treatments, tests and monitoring. Compared with the traditional methods, intracardiac electrocardiogram (ECG)-guided method has the potential to guide more accurate tip positioning of PICCs. This study aimed to clinically evaluate the effectiveness of an intracardiac ECG to guide the tip positioning by monitoring characteristic P-wave changes. In this study, eligible patients enrolled September 2011 to May 2012 according to the inclusion and exclusion criteria received the catheterization monitored by intracardiac ECG. Then chest radiography was performed to check the catheter position. The results revealed that, with 117 eligible patients, all bar one patient who died (n = 116) completed the study, including 60 males and 56 females aged 51.2 ± 15.1 years. Most (n = 113, > 97%) had characteristic P-wave changes. The intracardiac ECG-guided positioning procedure achieved correct placement for 112 patients (96.56%), demonstrating 99.12% sensitivity and 100% specificity. In conclusion, the intracardiac ECG can be a promising technique to guide tip positioning of PICCs. However, since the sample size in this study is limited, more experience and further study during clinical practice are needed to demonstrate achievement of optimal catheterization outcomes. © 2015 John Wiley & Sons Australia, Ltd.

  2. A comparison of auditory evoked potentials to acoustic beats and to binaural beats

    OpenAIRE

    Pratt, H; Starr, A; Michalewski, HJ; Dimitrijevic, A; Bleich, N; Mittelman, N

    2010-01-01

    The purpose of this study was to compare cortical brain responses evoked by amplitude modulated acoustic beats of 3 and 6 Hz in tones of 250 and 1000 Hz with those evoked by their binaural beats counterparts in unmodulated tones to indicate whether the cortical processes involved differ. Event-related potentials (ERPs) were recorded to 3- and 6-Hz acoustic and binaural beats in 2000 ms duration 250 and 1000 Hz tones presented with approximately 1 s intervals. Latency, amplitude and source cur...

  3. Navigation accuracy for an intracardiac procedure using ultrasound enhanced virtual reality

    Science.gov (United States)

    Wiles, Andrew D.; Guiraudon, Gerard M.; Moore, John; Wedlake, Christopher; Linte, Cristian A.; Bainbridge, Daniel; Jones, Douglas L.; Peters, Terry M.

    2007-03-01

    Minimally invasive techniques for use inside the beating heart, such as mitral valve replacement and septal defect repair, are the focus of this work. Traditional techniques for these procedures require an open chest approach and a cardiopulmonary bypass machine. New techniques using port access and a combined surgical guidance tool that includes an overlaid two-dimensional ultrasound image in a virtual reality environment are being developed. To test this technique, a cardiac phantom was developed to simulate the anatomy. The phantom consists of an acrylic box filled with a 7% glycerol solution with ultrasound properties similar to human tissue. Plate inserts mounted in the box simulate the physical anatomy. An accuracy assessment was completed to evaluate the performance of the system. Using the cardiac phantom, a 2mm diameter glass toroid was attached to a vertical plate as the target location. An elastic material was placed between the target and plate to simulate the target lying on a soft tissue structure. The target was measured using an independent measurement system and was represented as a sphere in the virtual reality system. The goal was to test the ability of a user to probe the target using three guidance methods: (i) 2D ultrasound only, (ii) virtual reality only and (iii) ultrasound enhanced virtual reality. Three users attempted the task three times each for each method. An independent measurement system was used to validate the measurement. The ultrasound imaging alone was poor in locating the target (5.42 mm RMS) while the other methods proved to be significantly better (1.02 mm RMS and 1.47 mm RMS respectively). The ultrasound enhancement is expected to be more useful in a dynamic environment where the system registration may be disturbed.

  4. From music-beat to heart-beat: a journey in the complex interactions between music, brain and heart.

    Science.gov (United States)

    Cervellin, Gianfranco; Lippi, Giuseppe

    2011-08-01

    Although the potential influence of music in eliciting organic reactions has been appreciated since the ancient Assyrian and Greek cultures, its relationship with body responses has been believed for long to belong to the field of magic. Growing experimental evidence now attests that some kind of music might indeed modulate several cardiac and neurological functions, as well as trigger biochemical measurable stress-reducing effects in certain individuals, mostly depending on their subjective musical education. On this basis, music has been increasingly used as a therapeutic tool in the treatment of different diseases in healthy and ill subjects over recent years (e.g., the so called "Mozart effect"), although the underlying scientific background is still poorly understood. The aim of this article is to review the current scientific evidences about the complex and multifaceted interactions between music and human biology. Copyright © 2011 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

  5. A kinematic approach for efficient and robust simulation of the cardiac beating motion.

    Directory of Open Access Journals (Sweden)

    Takashi Ijiri

    Full Text Available Computer simulation techniques for cardiac beating motions potentially have many applications and a broad audience. However, most existing methods require enormous computational costs and often show unstable behavior for extreme parameter sets, which interrupts smooth simulation study and make it difficult to apply them to interactive applications. To address this issue, we present an efficient and robust framework for simulating the cardiac beating motion. The global cardiac motion is generated by the accumulation of local myocardial fiber contractions. We compute such local-to-global deformations using a kinematic approach; we divide a heart mesh model into overlapping local regions, contract them independently according to fiber orientation, and compute a global shape that satisfies contracted shapes of all local regions as much as possible. A comparison between our method and a physics-based method showed that our method can generate motion very close to that of a physics-based simulation. Our kinematic method has high controllability; the simulated ventricle-wall-contraction speed can be easily adjusted to that of a real heart by controlling local contraction timing. We demonstrate that our method achieves a highly realistic beating motion of a whole heart in real time on a consumer-level computer. Our method provides an important step to bridge a gap between cardiac simulations and interactive applications.

  6. The beat-wave accelerator: Twenty questions

    International Nuclear Information System (INIS)

    Lawson, J.D.

    1985-01-01

    Many questions in the field of accelerator physics, plasma physics and laser technology need to be addressed if a useful accelerator based on the beat-wave principle is to be constructed. Many of these must be considered together rather than sequentially. An attempt has been made to set out a number of the more important questions in a logical manner. (orig.)

  7. Acoustical sensing of cardiomyocyte cluster beating.

    Science.gov (United States)

    Tymchenko, Nina; Kunze, Angelika; Dahlenborg, Kerstin; Svedhem, Sofia; Steel, Daniella

    2013-06-14

    Spontaneously beating human pluripotent stem cell-derived cardiomyocytes clusters (CMCs) represent an excellent in vitro tool for studies of human cardiomyocyte function and for pharmacological cardiac safety assessment. Such testing typically requires highly trained operators, precision plating, or large cell quantities, and there is a demand for real-time, label-free monitoring of small cell quantities, especially rare cells and tissue-like structures. Array formats based on sensing of electrical or optical properties of cells are being developed and in use by the pharmaceutical industry. A potential alternative to these techniques is represented by the quartz crystal microbalance with dissipation monitoring (QCM-D) technique, which is an acoustic surface sensitive technique that measures changes in mass and viscoelastic properties close to the sensor surface (from nm to μm). There is an increasing number of studies where QCM-D has successfully been applied to monitor properties of cells and cellular processes. In the present study, we show that spontaneous beating of CMCs on QCM-D sensors can be clearly detected, both in the frequency and the dissipation signals. Beating rates in the range of 66-168 bpm for CMCs were detected and confirmed by simultaneous light microscopy. The QCM-D beating profile was found to provide individual fingerprints of the hPS-CMCs. The presented results point towards acoustical assays for evaluation cardiotoxicity. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  8. Newborn infants detect the beat in music

    NARCIS (Netherlands)

    Winkler, I.; Háden, G.P.; Ladinig, O.; Sziller, I.; Honing, H.

    2009-01-01

    To shed light on how humans can learn to understand music, we need to discover what the perceptual capabilities with which infants are born. Beat induction, the detection of a regular pulse in an auditory signal, is considered a fundamental human trait that, arguably, played a decisive role in the

  9. Intracardiac Echocardiography Guided Transeptal Catheter Injection of Microspheres for Assessment of Cerebral Microcirculation in Experimental Models

    Directory of Open Access Journals (Sweden)

    Judith Bellapart

    2013-01-01

    Full Text Available The use of microspheres for the determination of regional microvascular blood flow (RMBF has previously used different approaches. This study presents for the first time the intracardiac injection of microspheres using transeptal puncture under intracardiac echocardiography guidance. Five Merino sheep were instrumented and cardiovascularly supported according to local guidelines. Two catheter sheaths into the internal jugular vein facilitated the introduction of an intracardiac probe and transeptal catheter, respectively. Five million colour coded microspheres were injected into the left atrium via this catheter. After euthanasia the brain was used as proof of principle and the endpoint for determination of microcirculation at different time points. Homogeneous allocation of microspheres to different regions of the brain was found over time. Alternate slices from both hemispheres showed the following flow ranges: for slice 02; 0.57–1.02 mL/min/g, slice 04; 0.45–1.42 mL/min/g, slice 06; 0.35–1.87 mL/min/g, slice 08; 0.46–1.77 mL/min/g, slice 10; 0.34–1.28 mL/min/g. A mixed effect regression model demonstrated that the confidence interval did include zero suggesting that the apparent variability intra- and intersubject was not statistically significant, supporting the stability and reproducibility of the injection technique. This study demonstrates the feasibility of the transeptal injection of microspheres, showing a homogeneous distribution of blood flow through the brain unchanged over time and has established a new interventional model for the measurement of RMBF in ovine models.

  10. The Impact of Monaural Beat Stimulation on Anxiety and Cognition

    OpenAIRE

    Chaieb, Leila; Wilpert, Elke C.; Hoppe, Christian; Axmacher, Nikolai; Fell, Juergen

    2017-01-01

    Application of auditory beat stimulation has been speculated to provide a promising new tool with which to alleviate symptoms of anxiety and to enhance cognition. In spite of reportedly similar EEG effects of binaural and monaural beats, data on behavioral effects of monaural beats are still lacking. Therefore, we examined the impact of monaural beat stimulation on anxiety, mood and memory performance. We aimed to target states related to anxiety levels and general well-being, in addition to ...

  11. Relationship between age and location of the apex beat among ...

    African Journals Online (AJOL)

    Location of apex beat is an integral part of routine cardiovascular system examination in clinical practice. However, there is paucity of ... Apex beat location in the intercostal space was determined and distance of apex beat from the midline, midclavicular line and nipple lines were measured. The measured distances were ...

  12. Detection of intra-cardiac and intra-arterial thrombi using labelled platelets

    International Nuclear Information System (INIS)

    Bernard, P.J.; Laforte, C. de

    1990-01-01

    Scintigraphy with 111 Indium labelled platelets is a powerful tool to detect platelet deposits in vessels. This quantitative and functional imaging method needs a labeling procedure which completely preserves the properties of the platelets and allows the concept of hematologically active clot. Three main groups of patients were examined. 1-91 hematologically active intra-cardiac thrombi were detected. The follow-up of 19 of them shows 5 deaths and 7 cerebral embolisms. 2-372 patients with lower limb ischemia, mainly in the case of blue toe syndrome were examined. 158 times a comparison with the surgical patterns was possible, there were 3 false positive and 9 false negative results. 3-In a group of 310 patients with transient cerebro-vascular accidents, 38 times the records were poorly significant. In 27 patients we were able to compare the morphological examinations (including platelet scintigraphy) to the anatomical findings. Sensitivity was only 64% and specificity 71%. As in the cases of intra-cardiac thrombi, the method allows the follow-up of pharmacological therapy. Platelets labelled with 111 Indium provide the means for sensitive and specific detection of hematologically active clots in cardiac and arterial pathology [fr

  13. Intra-cardiac remote ischemic post-conditioning attenuates ischemia-reperfusion injury in rats.

    Science.gov (United States)

    Fang, Jun; Chen, Lianglong; Wu, Liming; Li, Weiwei

    2009-12-01

    It remains unknown whether brief occlusion and relaxation of remote non-infarct-related coronary arteries limits infarct size. We tested the hypothesis that repetitive, brief, non-infarcting ischemia in one remote myocardial region, applied before sustained reperfusion to another intra-cardiac vasculature following infarcting ischemia, attenuates ischemia-reperfusion injury. In anesthetized open-chest rats, the left main coronary artery (LCA) was occluded for 30 min followed by sustained relaxation for 120 min. All rats were randomly allocated to six groups (n=8): without other interventions; Intra-cardiac remote ischemic post-conditioning (R-Post): before LCA relaxation, 3 cycles of 10 s ischemia by occluding the circumflex branch and 10 s reperfusion by relaxing it were applied; Atractyloside (Atr): given intravenously with atractyloside, an opener of the mitochondrial permeability transition pore; R-Post + Atr; Classical ischemic post-conditioning (Post): 3 cycles of 10 s reperfusion followed by 10 s ischemia were applied before 120 min of LCA relaxation; Sham: without LCA occlusion. We evaluated infarct size, cardiac function, cardiomyocyte ultrastructure and inflammatory processes. Compared with CONTROL, at the end of sustained reperfusion, R-Post and Post had smaller infarcts (respectively, 49%+/-5% vs. 32%+/-6% and 26%+/-5%, pinjury, and inhibition of the mitochondrial permeability transition pore opening may be involved in this cardioprotection.

  14. The Impact of Monaural Beat Stimulation on Anxiety and Cognition

    Directory of Open Access Journals (Sweden)

    Leila Chaieb

    2017-05-01

    Full Text Available Application of auditory beat stimulation has been speculated to provide a promising new tool with which to alleviate symptoms of anxiety and to enhance cognition. In spite of reportedly similar EEG effects of binaural and monaural beats, data on behavioral effects of monaural beats are still lacking. Therefore, we examined the impact of monaural beat stimulation on anxiety, mood and memory performance. We aimed to target states related to anxiety levels and general well-being, in addition to long-term and working memory processes, using monaural beats within the range of main cortical rhythms. Theta (6 Hz, alpha (10 Hz and gamma (40 Hz beat frequencies, as well as a control stimulus were applied to healthy participants for 5 min. After each stimulation period, participants were asked to evaluate their current mood state and to perform cognitive tasks examining long-term and working memory processes, in addition to a vigilance task. Monaural beat stimulation was found to reduce state anxiety. When evaluating responses for the individual beat frequencies, positive effects on state anxiety were observed for all monaural beat conditions compared to control stimulation. Our results indicate a role for monaural beat stimulation in modulating state anxiety and are in line with previous studies reporting anxiety-reducing effects of auditory beat stimulation.

  15. The Impact of Monaural Beat Stimulation on Anxiety and Cognition.

    Science.gov (United States)

    Chaieb, Leila; Wilpert, Elke C; Hoppe, Christian; Axmacher, Nikolai; Fell, Juergen

    2017-01-01

    Application of auditory beat stimulation has been speculated to provide a promising new tool with which to alleviate symptoms of anxiety and to enhance cognition. In spite of reportedly similar EEG effects of binaural and monaural beats, data on behavioral effects of monaural beats are still lacking. Therefore, we examined the impact of monaural beat stimulation on anxiety, mood and memory performance. We aimed to target states related to anxiety levels and general well-being, in addition to long-term and working memory processes, using monaural beats within the range of main cortical rhythms. Theta (6 Hz), alpha (10 Hz) and gamma (40 Hz) beat frequencies, as well as a control stimulus were applied to healthy participants for 5 min. After each stimulation period, participants were asked to evaluate their current mood state and to perform cognitive tasks examining long-term and working memory processes, in addition to a vigilance task. Monaural beat stimulation was found to reduce state anxiety. When evaluating responses for the individual beat frequencies, positive effects on state anxiety were observed for all monaural beat conditions compared to control stimulation. Our results indicate a role for monaural beat stimulation in modulating state anxiety and are in line with previous studies reporting anxiety-reducing effects of auditory beat stimulation.

  16. The impact of binaural beats on creativity

    OpenAIRE

    Reedijk, Susan A.; Bolders, Anne; Hommel, Bernhard

    2013-01-01

    Human creativity relies on a multitude of cognitive processes, some of which are influenced by the neurotransmitter dopamine. This suggests that creativity could be enhanced by interventions that either modulate the production or transmission of dopamine directly, or affect dopamine-driven processes. In the current study we hypothesized that creativity can be influenced by means of binaural beats, an auditory illusion that is considered a form of cognitive entrainment that operates through st...

  17. Auditory driving of the autonomic nervous system: Listening to theta-frequency binaural beats post-exercise increases parasympathetic activation and sympathetic withdrawal.

    Science.gov (United States)

    McConnell, Patrick A; Froeliger, Brett; Garland, Eric L; Ives, Jeffrey C; Sforzo, Gary A

    2014-01-01

    Binaural beats are an auditory illusion perceived when two or more pure tones of similar frequencies are presented dichotically through stereo headphones. Although this phenomenon is thought to facilitate state changes (e.g., relaxation), few empirical studies have reported on whether binaural beats produce changes in autonomic arousal. Therefore, the present study investigated the effects of binaural beating on autonomic dynamics [heart rate variability (HRV)] during post-exercise relaxation. Subjects (n = 21; 18-29 years old) participated in a double-blind, placebo-controlled study during which binaural beats and placebo were administered over two randomized and counterbalanced sessions (within-subjects repeated-measures design). At the onset of each visit, subjects exercised for 20-min; post-exercise, subjects listened to either binaural beats ('wide-band' theta-frequency binaural beats) or placebo (carrier tones) for 20-min while relaxing alone in a quiet, low-light environment. Dependent variables consisted of high-frequency (HF, reflecting parasympathetic activity), low-frequency (LF, reflecting sympathetic and parasympathetic activity), and LF/HF normalized powers, as well as self-reported relaxation. As compared to the placebo visit, the binaural-beat visit resulted in greater self-reported relaxation, increased parasympathetic activation and increased sympathetic withdrawal. By the end of the 20-min relaxation period there were no observable differences in HRV between binaural-beat and placebo visits, although binaural-beat associated HRV significantly predicted subsequent reported relaxation. Findings suggest that listening to binaural beats may exert an acute influence on both LF and HF components of HRV and may increase subjective feelings of relaxation.

  18. Auditory driving of the autonomic nervous system: Listening to theta-frequency binaural beats post-exercise increases parasympathetic activation and sympathetic withdrawal

    Directory of Open Access Journals (Sweden)

    Patrick eMcConnell

    2014-11-01

    Full Text Available Binaural beats are an auditory illusion perceived when two or more pure tones of similar frequencies are presented dichotically through stereo headphones. Although this phenomenon is thought to facilitate state changes (e.g., relaxation, few empirical studies have reported on whether binaural beats produce changes in autonomic arousal. Therefore, the present study investigated the effects of binaural beating on autonomic dynamics (heart-rate variability (HRV during post-exercise relaxation. Subjects (n = 21; 18-29 years old participated in a double-blind, placebo-controlled study during which binaural beats and placebo were administered over two randomized and counterbalanced sessions (within-subjects repeated-measures design. At the onset of each visit, subjects exercised for 20-min; post-exercise, subjects listened to either binaural beats (‘wide-band’ theta-frequency binaural beats or placebo (carrier tone for 20-min while relaxing alone in a quiet, low-light environment. Dependent variables consisted of high frequency (HF, reflecting parasympathetic activity, low frequency (LF, reflecting sympathetic and parasympathetic activity and LF/HF normalized powers, as well as self-reported relaxation. As compared to the placebo visit, the binaural beat visit resulted in greater self-reported relaxation, as well as increased parasympathetic activation and sympathetic withdrawal. By the end of the 20-min relaxation period there were no observable differences in HRV between binaural beat and placebo visits, although binaural-beat associated HRV significantly predicted subsequent reported relaxation. Findings suggest that listening to binaural beats may exert an acute influence on both LF and HF components of HRV and may increase subjective feelings of relaxation.

  19. Cortical evoked potentials to an auditory illusion: binaural beats.

    Science.gov (United States)

    Pratt, Hillel; Starr, Arnold; Michalewski, Henry J; Dimitrijevic, Andrew; Bleich, Naomi; Mittelman, Nomi

    2009-08-01

    To define brain activity corresponding to an auditory illusion of 3 and 6Hz binaural beats in 250Hz or 1000Hz base frequencies, and compare it to the sound onset response. Event-Related Potentials (ERPs) were recorded in response to unmodulated tones of 250 or 1000Hz to one ear and 3 or 6Hz higher to the other, creating an illusion of amplitude modulations (beats) of 3Hz and 6Hz, in base frequencies of 250Hz and 1000Hz. Tones were 2000ms in duration and presented with approximately 1s intervals. Latency, amplitude and source current density estimates of ERP components to tone onset and subsequent beats-evoked oscillations were determined and compared across beat frequencies with both base frequencies. All stimuli evoked tone-onset P(50), N(100) and P(200) components followed by oscillations corresponding to the beat frequency, and a subsequent tone-offset complex. Beats-evoked oscillations were higher in amplitude with the low base frequency and to the low beat frequency. Sources of the beats-evoked oscillations across all stimulus conditions located mostly to left lateral and inferior temporal lobe areas in all stimulus conditions. Onset-evoked components were not different across stimulus conditions; P(50) had significantly different sources than the beats-evoked oscillations; and N(100) and P(200) sources located to the same temporal lobe regions as beats-evoked oscillations, but were bilateral and also included frontal and parietal contributions. Neural activity with slightly different volley frequencies from left and right ear converges and interacts in the central auditory brainstem pathways to generate beats of neural activity to modulate activities in the left temporal lobe, giving rise to the illusion of binaural beats. Cortical potentials recorded to binaural beats are distinct from onset responses. Brain activity corresponding to an auditory illusion of low frequency beats can be recorded from the scalp.

  20. Ivabradine in stable coronary artery disease without clinical heart failure

    DEFF Research Database (Denmark)

    Fox, Kim; Ford, Ian; Steg, Philippe Gabriel

    2014-01-01

    BACKGROUND: An elevated heart rate is an established marker of cardiovascular risk. Previous analyses have suggested that ivabradine, a heart-rate-reducing agent, may improve outcomes in patients with stable coronary artery disease, left ventricular dysfunction, and a heart rate of 70 beats per m...

  1. The role of flow in the morphodynamics of embryonic heart

    Science.gov (United States)

    Gharib, Morteza

    2017-11-01

    Nature has shown us that some hearts do not require valves to achieve unidirectional flow. In its earliest stages, the vertebrate heart consists of a primitive tube that drives blood through a simple vascular network nourishing tissues and other developing organ systems. We have shown that in the case of the embryonic zebrafish heart, an elastic wave resonance mechanism based on impedance mismatches at the boundaries of the heart tube is the likely mechanism responsible for the valveless pumping behavior. When functioning normally, mature heart valves prevent intracardiac retrograde blood flow; before valves develop there is considerable regurgitation, resulting in oscillatory flow between the atrium and ventricle. We show that reversing flows are particularly strong stimuli to endothelial cells and that heart valves form as a developmental response to oscillatory blood flow through the maturing heart.

  2. Beat-Frequency/Microsphere Medical Ultrasonic Imaging

    Science.gov (United States)

    Yost, William T.; Cantrell, John H.; Pretlow, Robert A., III

    1995-01-01

    Medical ultrasonic imaging system designed to provide quantitative data on various flows of blood in chambers, blood vessels, muscles, and tissues of heart. Sensitive enough to yield readings on flows of blood in heart even when microspheres used as ultrasonic contrast agents injected far from heart and diluted by circulation of blood elsewhere in body.

  3. 4D ICE: A 2D Array Transducer with Integrated ASIC in a 10 Fr Catheter for Real-Time 3D Intracardiac Echocardiography.

    Science.gov (United States)

    Wildes, Douglas; Lee, Warren; Haider, Bruno; Cogan, Scott; Sundaresan, Krishnakumar; Mills, David; Yetter, Christopher; Hart, Patrick; Haun, Christopher; Concepcion, Mikael; Kirkhorn, Johan; Bitoun, Marc

    2016-10-12

    We developed a 2.5 x 6.6 mm 2D array transducer with integrated transmit/receive ASIC for 4D ICE (real-time 3D IntraCardiac Echocardiography) applications. The ASIC and transducer design were optimized so that the high voltage transmit, low-voltage TGC (time-gain control) and preamp, subaperture beamformer, and digital control circuits for each transducer element all fit within the 0.019 mm2 area of the element. The transducer assembly was deployed in a 10 Fr (3.3 mm diameter) catheter, integrated with a GE Vivid1 E9 ultrasound imaging system, and evaluated in three pre-clinical studies. 2D image quality and imaging modes were comparable to commercial 2D ICE catheters. The 4D field of view was at least 90° x 60° x 8 cm and could be imaged at 30 volumes/sec, sufficient to visualize cardiac anatomy and other diagnostic and therapy catheters. 4D ICE should significantly reduce X-ray fluoroscopy use and dose during electrophysiology (EP) ablation procedures. 4D ICE may be able to replace trans-esophageal echocardiography (TEE), and the associated risks and costs of general anesthesia, for guidance of some structural heart procedures.

  4. 4-D ICE: A 2-D Array Transducer With Integrated ASIC in a 10-Fr Catheter for Real-Time 3-D Intracardiac Echocardiography.

    Science.gov (United States)

    Wildes, Douglas; Lee, Warren; Haider, Bruno; Cogan, Scott; Sundaresan, Krishnakumar; Mills, David M; Yetter, Christopher; Hart, Patrick H; Haun, Christopher R; Concepcion, Mikael; Kirkhorn, Johan; Bitoun, Marc

    2016-12-01

    We developed a 2.5 ×6.6 mm 2 2 -D array transducer with integrated transmit/receive application-specific integrated circuit (ASIC) for real-time 3-D intracardiac echocardiography (4-D ICE) applications. The ASIC and transducer design were optimized so that the high-voltage transmit, low-voltage time-gain control and preamp, subaperture beamformer, and digital control circuits for each transducer element all fit within the 0.019-mm 2 area of the element. The transducer assembly was deployed in a 10-Fr (3.3-mm diameter) catheter, integrated with a GE Vivid E9 ultrasound imaging system, and evaluated in three preclinical studies. The 2-D image quality and imaging modes were comparable to commercial 2-D ICE catheters. The 4-D field of view was at least 90 ° ×60 ° ×8 cm and could be imaged at 30 vol/s, sufficient to visualize cardiac anatomy and other diagnostic and therapy catheters. 4-D ICE should significantly reduce X-ray fluoroscopy use and dose during electrophysiology ablation procedures. 4-D ICE may be able to replace transesophageal echocardiography (TEE), and the associated risks and costs of general anesthesia, for guidance of some structural heart procedures.

  5. 18F-FDG-PET Scanning Confirmed Infected Intracardiac Device-Leads with Abiotrophia defectiva

    Directory of Open Access Journals (Sweden)

    Sonja van Roeden

    2016-01-01

    Full Text Available Abiotrophia species are relatively slow growing pathogens, which may be present as commensal flora. However, invasive infections are frequently reported, like endocarditis, septic arthritis, osteomyelitis, and many other types of infection. In this case report we describe a 65-year-old male patient with an intracardiac device- (ICD- lead infection caused by Abiotrophia defectiva. Diagnosis was confirmed by 18F-FDG-PET scanning. This is remarkable, since Abiotrophia defectiva is a slow growing pathogen causing low-grade infections. This case demonstrates that although infection of ICD-leads cannot be excluded in case of 18F-FDG-PET-negative findings, positive findings are highly suggestive for infection.

  6. Appropriate threshold levels of cardiac beat-to-beat variation in semi-automatic analysis of equine ECG recordings

    DEFF Research Database (Denmark)

    Madsen, Mette Flethøj; Kanters, Jørgen K.; Pedersen, Philip Juul

    2016-01-01

    Background: Although premature beats are a matter of concern in horses, the interpretation of equine ECG recordings is complicated by a lack of standardized analysis criteria and a limited knowledge of the normal beat-to-beat variation of equine cardiac rhythm. The purpose of this study was to de......Background: Although premature beats are a matter of concern in horses, the interpretation of equine ECG recordings is complicated by a lack of standardized analysis criteria and a limited knowledge of the normal beat-to-beat variation of equine cardiac rhythm. The purpose of this study...... was to determine the appropriate threshold levels of maximum acceptable deviation of RR intervals in equine ECG analysis, and to evaluate a novel two-step timing algorithm by quantifying the frequency of arrhythmias in a cohort of healthy adult endurance horses. Results: Beat-to-beat variation differed......, range 1–24). Conclusions: Beat-to-beat variation of equine cardiac rhythm varies according to HR, and threshold levels in equine ECG analysis should be adjusted accordingly. Standardization of the analysis criteria will enable comparisons of studies and follow-up examinations of patients. A small number...

  7. The Harvard Beat Assessment Test (H-BAT: A Battery for Assessing Beat Perception and Production and their Dissociation

    Directory of Open Access Journals (Sweden)

    Shinya eFujii

    2013-11-01

    Full Text Available Humans have the abilities to perceive, produce, and synchronize with a musical beat, yet there are widespread individual differences. To investigate these abilities and to determine if a dissociation between beat perception and production exists, we developed the Harvard Beat Assessment Test (H-BAT, a new battery that assesses beat perception and production abilities. H-BAT consists of four subtests: 1 music tapping test (MTT, 2 beat saliency test (BST, 3 beat interval test (BIT, and 4 beat finding and interval test (BFIT. MTT measures the degree of tapping synchronization with the beat of music, whereas BST, BIT, and BFIT measure perception and production thresholds via psychophysical adaptive stair-case methods. We administered the H-BAT on thirty individuals and investigated the performance distribution across these individuals in each subtest. There was a wide distribution in individual abilities to tap in synchrony with the beat of music during the MTT. The degree of synchronization consistency was negatively correlated with thresholds in the BST, BIT, and BFIT: a lower degree of synchronization was associated with higher perception and production thresholds. H-BAT can be a useful tool in determining an individual’s ability to perceive and produce a beat within a single session.

  8. Significance of beating observed in earthquake responses of buildings

    Science.gov (United States)

    Çelebi, Mehmet; Ghahari, S. F.; Taciroglu, E.

    2016-01-01

    The beating phenomenon observed in the recorded responses of a tall building in Japan and another in the U.S. are examined in this paper. Beating is a periodic vibrational behavior caused by distinctive coupling between translational and torsional modes that typically have close frequencies. Beating is prominent in the prolonged resonant responses of lightly damped structures. Resonances caused by site effects also contribute to accentuating the beating effect. Spectral analyses and system identification techniques are used herein to quantify the periods and amplitudes of the beating effects from the strong motion recordings of the two buildings. Quantification of beating effects is a first step towards determining remedial actions to improve resilient building performance to strong earthquake induced shaking.

  9. Beate Wagner-Hasel – notice

    OpenAIRE

    2017-01-01

    Beate Wagner-Hasel est professeure à la faculté d’histoire de l’Université Leibnitz de Hanovre. Elle a fait des études d’histoire, de philologie allemande et de journalisme à Münster et Berlin (Université Libre et Université Technique). En 1980, elle a soutenu son doctorat en histoire ancienne à l’Université Technique de Berlin, en 1995 elle a passé son habilitation à l’Université Technique de Darmstadt. Elle a enseigné aux universités de Darmstadt, Kassel, Münster, Basel et Salzburg avant d’...

  10. A new Bayesian Earthquake Analysis Tool (BEAT)

    Science.gov (United States)

    Vasyura-Bathke, Hannes; Dutta, Rishabh; Jónsson, Sigurjón; Mai, Martin

    2017-04-01

    Modern earthquake source estimation studies increasingly use non-linear optimization strategies to estimate kinematic rupture parameters, often considering geodetic and seismic data jointly. However, the optimization process is complex and consists of several steps that need to be followed in the earthquake parameter estimation procedure. These include pre-describing or modeling the fault geometry, calculating the Green's Functions (often assuming a layered elastic half-space), and estimating the distributed final slip and possibly other kinematic source parameters. Recently, Bayesian inference has become popular for estimating posterior distributions of earthquake source model parameters given measured/estimated/assumed data and model uncertainties. For instance, some research groups consider uncertainties of the layered medium and propagate these to the source parameter uncertainties. Other groups make use of informative priors to reduce the model parameter space. In addition, innovative sampling algorithms have been developed that efficiently explore the often high-dimensional parameter spaces. Compared to earlier studies, these improvements have resulted in overall more robust source model parameter estimates that include uncertainties. However, the computational demands of these methods are high and estimation codes are rarely distributed along with the published results. Even if codes are made available, it is often difficult to assemble them into a single optimization framework as they are typically coded in different programing languages. Therefore, further progress and future applications of these methods/codes are hampered, while reproducibility and validation of results has become essentially impossible. In the spirit of providing open-access and modular codes to facilitate progress and reproducible research in earthquake source estimations, we undertook the effort of producing BEAT, a python package that comprises all the above-mentioned features in one

  11. HEART RATE DURING SLEEP: IMPLICATIONS FOR MONITORING TRAINING STATUS

    Directory of Open Access Journals (Sweden)

    Miriam R. Waldeck

    2003-12-01

    Full Text Available Resting heart rate has sometimes been used as a marker of training status. It is reasonable to assume that the relationship between heart rate and training status should be more evident during sleep when extraneous factors that may influence heart rate are reduced. Therefore the aim of the study was to assess the repeatability of monitoring heart rate during sleep when training status remained unchanged, to determine if this measurement had sufficient precision to be used as a marker of training status. The heart rate of ten female subjects was monitored for 24 hours on three occasions over three weeks whilst training status remained unchanged. Average, minimum and maximum heart rate during sleep was calculated. The average heart rate of the group during sleep was similar on each of the three tests (65 ± 9, 63 ± 6 and 67 ± 7 beats·min-1 respectively. The range in minimum heart rate variation during sleep for all subjects over the three testing sessions was from 0 to 10 beats·min-1 (mean = 5 ± 3 beats·min-1 and for maximum heart rate variation was 2 to 31 beats·min-1 (mean = 13 ± 9 beats·min-1. In summary it was found that on an individual basis the minimum heart rate during sleep varied by about 8 beats·min-1. This amount of intrinsic day-to-day variation needs to be considered when changes in heart rate that may occur with changes in training status are interpreted

  12. Cardiac magnetic resonance imaging in patients with congenital heart disease

    International Nuclear Information System (INIS)

    Kreitner, Karl-Friedrich; Sorantin, Erich

    2015-01-01

    The prevalence of congenital heart disease (CHD) is around 10 per 1000 live births in Germany. More than 90 % of these patients will survive into adulthood due to improvements in therapy. The classification of CHD may be based according to the anatomic structures involved, to the presence of an intracardiac shunt, the presence of a cyanosis and the intensity of therapy and complexity of the disease. Nearly half of all patients with CHD suffer from an intracardiac shunt, whereas complex cases such as patients with a tetralogy of Fallot or transposition of the great arteries are much more rare. Cardiac magnetic resonance imaging plays an important role in the work-up and follow-up of patients with CHD, especially after infancy and childhood. Depending on the abnormality in question, a multiparametric examination protocol is mandatory. Knowledge of operative procedures and findings of other imaging modalities help to optimize examination and time needed for it.

  13. Beats on the Table: Beat Writing in the Chicago Review and Big Table

    Directory of Open Access Journals (Sweden)

    Jaap van der Bent

    2012-07-01

    Full Text Available Normal 0 21 false false false NL X-NONE X-NONE MicrosoftInternetExplorer4 Kleine literaire tijdschriften, zogenaamde little magazines, hebben een belangrijke rol gespeeld bij de doorbraak, in de loop van de jaren vijftig, van de Amerikaanse Beat Generation. Aangezien grotere uitgeverijen en de gevestigde tijdschriften lange tijd terugschrokken voor de zowel inhoudelijk als formeel van de norm afwijkende uitingen van de Beats, verscheen hun werk aanvankelijk vooral in kleinere tijdschriften als de twee waaraan in dit artikel aandacht wordt besteed: de Chicago Review en Big Table. Aan de hand van een beschrijving van de inhoud van deze twee tijdschriften wordt geprobeerd duidelijk te maken hoe het werk van de Beat Generation zich in deze tijdschriften gaandeweg een eigen plaats verwierf. Speciale aandacht wordt besteed aan de rol van de redacteuren Irving Rosenthal en Paul Carroll; door zijn uitgekiende strategie om voor het omstreden werk van Beat-auteur William S. Burroughs geleidelijk een steeds grotere plaats in te ruimen, bepaalde vooral Rosenthal het veranderende karakter van de Chicago Review. De veranderingen bij dat tijdschrift verliepen niet zonder slag of stoot en waren voor de eigenaar ervan, de University of Chicago, op een gegeven moment aanleiding om de Chicago Review aan censuur te onderwerpen. Ook deze censuur en de reactie erop, de oprichting van Big Table, worden in het artikel belicht.

  14. Binaural auditory beats affect vigilance performance and mood.

    Science.gov (United States)

    Lane, J D; Kasian, S J; Owens, J E; Marsh, G R

    1998-01-01

    When two tones of slightly different frequency are presented separately to the left and right ears the listener perceives a single tone that varies in amplitude at a frequency equal to the frequency difference between the two tones, a perceptual phenomenon known as the binaural auditory beat. Anecdotal reports suggest that binaural auditory beats within the electroencephalograph frequency range can entrain EEG activity and may affect states of consciousness, although few scientific studies have been published. This study compared the effects of binaural auditory beats in the EEG beta and EEG theta/delta frequency ranges on mood and on performance of a vigilance task to investigate their effects on subjective and objective measures of arousal. Participants (n = 29) performed a 30-min visual vigilance task on three different days while listening to pink noise containing simple tones or binaural beats either in the beta range (16 and 24 Hz) or the theta/delta range (1.5 and 4 Hz). However, participants were kept blind to the presence of binaural beats to control expectation effects. Presentation of beta-frequency binaural beats yielded more correct target detections and fewer false alarms than presentation of theta/delta frequency binaural beats. In addition, the beta-frequency beats were associated with less negative mood. Results suggest that the presentation of binaural auditory beats can affect psychomotor performance and mood. This technology may have applications for the control of attention and arousal and the enhancement of human performance.

  15. Predictive Value of Beat-to-Beat QT Variability Index across the Continuum of Left Ventricular Dysfunction: Competing Risks of Non-cardiac or Cardiovascular Death, and Sudden or Non-Sudden Cardiac Death

    Science.gov (United States)

    Tereshchenko, Larisa G.; Cygankiewicz, Iwona; McNitt, Scott; Vazquez, Rafael; Bayes-Genis, Antoni; Han, Lichy; Sur, Sanjoli; Couderc, Jean-Philippe; Berger, Ronald D.; de Luna, Antoni Bayes; Zareba, Wojciech

    2012-01-01

    Background The goal of this study was to determine the predictive value of beat-to-beat QT variability in heart failure (HF) patients across the continuum of left ventricular dysfunction. Methods and Results Beat-to-beat QT variability index (QTVI), heart rate variance (LogHRV), normalized QT variance (QTVN), and coherence between heart rate variability and QT variability have been measured at rest during sinus rhythm in 533 participants of the Muerte Subita en Insuficiencia Cardiaca (MUSIC) HF study (mean age 63.1±11.7; males 70.6%; LVEF >35% in 254 [48%]) and in 181 healthy participants from the Intercity Digital Electrocardiogram Alliance (IDEAL) database. During a median of 3.7 years of follow-up, 116 patients died, 52 from sudden cardiac death (SCD). In multivariate competing risk analyses, the highest QTVI quartile was associated with cardiovascular death [hazard ratio (HR) 1.67(95%CI 1.14-2.47), P=0.009] and in particular with non-sudden cardiac death [HR 2.91(1.69-5.01), P<0.001]. Elevated QTVI separated 97.5% of healthy individuals from subjects at risk for cardiovascular [HR 1.57(1.04-2.35), P=0.031], and non-sudden cardiac death in multivariate competing risk model [HR 2.58(1.13-3.78), P=0.001]. No interaction between QTVI and LVEF was found. QTVI predicted neither non-cardiac death (P=0.546) nor SCD (P=0.945). Decreased heart rate variability (HRV) rather than increased QT variability was the reason for increased QTVI in this study. Conclusions Increased QTVI due to depressed HRV predicts cardiovascular mortality and non-sudden cardiac death, but neither SCD nor excracardiac mortality in HF across the continuum of left ventricular dysfunction. Abnormally augmented QTVI separates 97.5% of healthy individuals from HF patients at risk. PMID:22730411

  16. Real-time Continuous Assessment Method for Mental and Physiological Condition using Heart Rate Variability

    Science.gov (United States)

    Yoshida, Yutaka; Yokoyama, Kiyoko; Ishii, Naohiro

    It is necessary to monitor the daily health condition for preventing stress syndrome. In this study, it was proposed the method assessing the mental and physiological condition, such as the work stress or the relaxation, using heart rate variability at real time and continuously. The instantanuous heart rate (HR), and the ratio of the number of extreme points (NEP) and the number of heart beats were calculated for assessing mental and physiological condition. In this method, 20 beats heart rate were used to calculate these indexes. These were calculated in one beat interval. Three conditions, which are sitting rest, performing mental arithmetic and watching relaxation movie, were assessed using our proposed algorithm. The assessment accuracies were 71.9% and 55.8%, when performing mental arithmetic and watching relaxation movie respectively. In this method, the mental and physiological condition was assessed using only 20 regressive heart beats, so this method is considered as the real time assessment method.

  17. KLASIFIKASI BEAT ARITMIA PADA SINYAL EKG MENGGUNAKAN FUZZY WAVELET LEARNING VECTOR QUANTIZATION

    Directory of Open Access Journals (Sweden)

    Elly Matul Imah

    2012-05-01

    Full Text Available Pengenalan pola beat dalam analisa rekaman elektrokardiogram (EKG menjadi bagian yang penting dalam deteksi penyakit jantung terutama aritmia. Banyak metode yang dikembangkan terkait dengan pengenalan pola beat, namun sebagian besar masih mengunakan algoritma klasifikasi klasik di mana masih belum mampu mengenali outlier klasifikasi. Fuzzy Learning Vector Quantization (FLVQ merupakan salah satu algoritma yang mampu untuk mengenali outlier klasifikasi tetapi juga memiliki kelemahan untuk sistem uji yang bukan data berkelompok. Dalam tulisan ini peneliti mengusulkan Fuzzy Wavelet LearningVector Quantization (FWLVQ, yaitu modifikasi FLVQ sehingga mampu mengatasi data crisp maupun data fuzzy dan juga memodifikasi inferensi sistemnya sebagai perpaduan model fuzzy Takagi Sugeno Kang dengan wavelet. Sinyal EKG diperoleh dari database MIT-BIH. Sistem pengenalan pola beat secara keseluruhan terbagi atas dua bagian yaitu data pra proses dan klasifikasi. Hasil percobaan diperoleh bahwa FWLVQ memiliki akurasi sebesar 90.20% untuk data yang tidak mengandung outlier klasifikasi dan 87.19% untuk data yang melibatkan outlier klasifikasi dengan rasio data uji outlier klasifikasi dengan data non-outlier sebesar 1:1. The recognition of beat pattern in analysis of recording an electrocardiogram (ECG becomes an important detection of heart disease, especially arrhythmias. Many methods are developed related to the recognition of beat patterns, but most still use the classical classification algorithms which are still not able to identify outlier classification. Fuzzy Learning Vector Quantization (FLVQ is one of the algorithms that can identify outlier classification but also has a weakness for test systems that are not grouped data. In this paper we propose a Fuzzy Wavelet Quantization Learning Vector (FWLVQ, which is modified so as to overcome FLVQ crisp data and fuzzy data and also modify the inference system as a combination of Takagi Sugeno Kang fuzzy model with

  18. What makes a rhythm complex? The influence of musical training and accent type on beat perception

    Science.gov (United States)

    Burgoyne, J. Ashley; Odijk, Daan; Honing, Henkjan; Grahn, Jessica A.

    2018-01-01

    Perception of a regular beat in music is inferred from different types of accents. For example, increases in loudness cause intensity accents, and the grouping of time intervals in a rhythm creates temporal accents. Accents are expected to occur on the beat: when accents are “missing” on the beat, the beat is more difficult to find. However, it is unclear whether accents occurring off the beat alter beat perception similarly to missing accents on the beat. Moreover, no one has examined whether intensity accents influence beat perception more or less strongly than temporal accents, nor how musical expertise affects sensitivity to each type of accent. In two experiments, we obtained ratings of difficulty in finding the beat in rhythms with either temporal or intensity accents, and which varied in the number of accents on the beat as well as the number of accents off the beat. In both experiments, the occurrence of accents on the beat facilitated beat detection more in musical experts than in musical novices. In addition, the number of accents on the beat affected beat finding more in rhythms with temporal accents than in rhythms with intensity accents. The effect of accents off the beat was much weaker than the effect of accents on the beat and appeared to depend on musical expertise, as well as on the number of accents on the beat: when many accents on the beat are missing, beat perception is quite difficult, and adding accents off the beat may not reduce beat perception further. Overall, the different types of accents were processed qualitatively differently, depending on musical expertise. Therefore, these findings indicate the importance of designing ecologically valid stimuli when testing beat perception in musical novices, who may need different types of accent information than musical experts to be able to find a beat. Furthermore, our findings stress the importance of carefully designing rhythms for social and clinical applications of beat perception, as

  19. Beat-wave generation of plasmons in semiconductor plasmas

    International Nuclear Information System (INIS)

    Berezhiani, V.I.; Mahajan, S.M.

    1995-08-01

    It is shown that in semiconductor plasmas, it is possible to generate large amplitude plasma waves by the beating of two laser beams with frequency difference close to the plasma frequency. For narrow gap seimconductors (for example n-type InSb), the system can simulate the physics underlying beat wave generation in relativistic gaseous plasmas

  20. Beat-wave generation of plasmons in semiconductor plasmas

    International Nuclear Information System (INIS)

    Berezhiani, V.I.; Mahajan, S.M.

    1995-08-01

    It is shown that in semiconductor plasmas, it is possible to generate large amplitude plasma waves by the beating of two laser beams with frequency difference close to the plasma frequency. For narrow gap semiconductor (for example n-type InSb), the system can simulate the physics underlying beat wave generation in relativistic gaseous plasmas. (author). 7 refs

  1. Movement Instruction to Facilitate Beat Competency in Instrumental Music

    Science.gov (United States)

    Conway, Colleen; Marshall, Herbert; Hartz, Barry

    2014-01-01

    This article offers instrumental directors at all levels some suggestions for the use of movement to facilitate "beat competency". We use the term beat competency to refer to a musician's ability to play with a consistent sense of pulse and balanced subdivision, as well as the eventual ability to bring that sense of pulse to reading…

  2. Beat Perception and Sociability: Evidence from Williams Syndrome.

    Science.gov (United States)

    Lense, Miriam D; Dykens, Elisabeth M

    2016-01-01

    Beat perception in music has been proposed to be a human universal that may have its origins in adaptive processes involving temporal entrainment such as social communication and interaction. We examined beat perception skills in individuals with Williams syndrome (WS), a genetic, neurodevelopmental disorder. Musical interest and hypersociability are two prominent aspects of the WS phenotype although actual musical and social skills are variable. On a group level, beat and meter perception skills were poorer in WS than in age-matched peers though there was significant individual variability. Cognitive ability, sound processing style, and musical training predicted beat and meter perception performance in WS. Moreover, we found significant relationships between beat and meter perception and adaptive communication and socialization skills in WS. Results have implications for understanding the role of predictive timing in both music and social interactions in the general population, and suggest music as a promising avenue for addressing social communication difficulties in WS.

  3. Experimental Observation of Chaotic Beats in Oscillators Sharing Nonlinearity

    Science.gov (United States)

    Paul Asir, M.; Jeevarekha, A.; Philominathan, P.

    This paper deals with the generation of chaotic beats in a system of two forced dissipative LCR oscillators sharing a nonlinear element. The presence of two external periodic excitations and a common nonlinear element in the chosen system enables the facile generation of chaotic beats. Thus rendered chaotic beats were characterized in both time domain and phase space. Lyapunov exponents and envelope of the beats were computed to diagnose the chaotic nature of the signals. The role of common nonlinearity on the complexity of the generated beats is discussed. Real-time experimental hardware implementation has also been done to confirm the subsistence of the phenomenon, for the first time. Extensive Multisim simulations were carried out to understand, a bit more about the shrinkage and revivals of state variables in phase space.

  4. Heart rate response to breathing

    DEFF Research Database (Denmark)

    Mehlsen, J; Pagh, K; Nielsen, J S

    1987-01-01

    Heart rate responses to stepwise and periodic changes in lung volume were studied in seven young healthy males. Stepwise inspiration and expiration both resulted in an increase in heart rate followed by a rapid decrease in heart rate. The fastest heart rate was reached in 1.6 +/- 0.5 s and in 3.......6 +/- 1.4 s in response to inspiration and expiration, respectively (P less than 0.01). The slowest heart rate was reached in 4.8 +/- 1.0 s and in 7.6 +/- 1.9 s in response to inspiration and expiration, respectively (P less than 0.01). Following this biphasic change the heart rate returned to a steady...... level. The difference between the fastest and the slowest heart rates was significantly larger in response to inspiration (21.7 +/- 7.3 beats per minute) than in response to expiration (12.0 +/- 7.3 beats per minute; P less than 0.01). Periodic changes in lung volume were performed with frequencies from...

  5. Human induced pluripotent stem cell-derived beating cardiac tissues on paper.

    Science.gov (United States)

    Wang, Li; Xu, Cong; Zhu, Yujuan; Yu, Yue; Sun, Ning; Zhang, Xiaoqing; Feng, Ke; Qin, Jianhua

    2015-11-21

    There is a growing interest in using paper as a biomaterial scaffold for cell-based applications. In this study, we made the first attempt to fabricate a paper-based array for the culture, proliferation, and direct differentiation of human induced pluripotent stem cells (hiPSCs) into functional beating cardiac tissues and create "a beating heart on paper." This array was simply constructed by binding a cured multi-well polydimethylsiloxane (PDMS) mold with common, commercially available paper substrates. Three types of paper material (print paper, chromatography paper and nitrocellulose membrane) were tested for adhesion, proliferation and differentiation of human-derived iPSCs. We found that hiPSCs grew well on these paper substrates, presenting a three-dimensional (3D)-like morphology with a pluripotent property. The direct differentiation of human iPSCs into functional cardiac tissues on paper was also achieved using our modified differentiation approach. The cardiac tissue retained its functional activities on the coated print paper and chromatography paper with a beating frequency of 40-70 beats per min for up to three months. Interestingly, human iPSCs could be differentiated into retinal pigment epithelium on nitrocellulose membrane under the conditions of cardiac-specific induction, indicating the potential roles of material properties and mechanical cues that are involved in regulating stem cell differentiation. Taken together, these results suggest that different grades of paper could offer great opportunities as bioactive, low-cost, and 3D in vitro platforms for stem cell-based high-throughput drug testing at the tissue/organ level and for tissue engineering applications.

  6. Beat wave current drive experiment on DDT

    International Nuclear Information System (INIS)

    Hwang, D.Q.

    1991-03-01

    Several improvements have been made to the beat wave experiment this year. We are now able to vary the magnetic field over a much larger range, the plasma density is more uniform, and the electron temperature is significantly higher than last year (making it easier to couple energy from the electrostatic wave into the electron distribution). We have found evidence that at higher magnetic fields, ω ce /ω pe > 1, that numerous electrostatic modes are excited. This may be due to the fact that for a bounded plasma, ω pe is allowed (for small wave numbers). Although we are still not sure why the rvec k matching criteria (rvec k 0 = rvec k 1 + rvec k e ) is not more restrictive. A 35 GHz microwave scattering diagnostic has been designed, built, and tested in order to make a less perturbing measure of the electrostatic wave

  7. Use of intra-cardiac ultrasound in the diagnosis of prosthetic valve malfunction.

    Science.gov (United States)

    Osman, Faizel; Steeds, Rick

    2007-10-01

    A 46-year old lady was under regular follow up for aortic valve replacement done in 2002 for aortic stenosis. The valve was a Carbomedics 19 mm bi-leaflet aortic valve prosthesis for which she had adequate anticoagulation since implantation. She had a past history of end stage renal failure, type 2 diabetes, hypertension, cerebrovascular disease and systemic lupus erythematosus. She was asymptomatic and had a routine transthoracic echocardiogram performed which revealed that her aortic valve prosthesis was well seated with an elevated velocity across the valve; the aortic valve leaflets were poorly visualised but appeared to be mobile. A transoesophageal echocardiogram (TOE) confirmed the markedly increased forward velocity across the aortic valve (maximum velocity 4.6 m/s) with small aortic root raising the possibility of pressure recovery phenomenon. Once again the leaflets were not clearly seen but appeared mobile despite the use of deep trans-gastric view. Fluoroscopy was performed and revealed that one of the leaflets was not moving. The patient had an intra-cardiac ultrasound scan (ACUSON AcuNav; Siemens) with the probe of the scanner within the right atrium. A long-axis view demonstrated the prosthetic aortic valve leaflets clearly (Fig. 1). A short-axis view of the prosthetic valve revealed an echogenic area at the six o'clock position; this may be due to pannus formation (Fig. 2); colour flow across the valve during systole revealed absence of colour flow though one of the leaflets due to the leaflet being stuck (Fig. 3). The sewing cuff of the Carbomedics valve is coated with biolite carbon, which is an anti-thrombotic agent that prevents adhesion of thrombus or pannus on the sewing cuff. There are few reports of Carbomedics valve dysfunction by pannus formation in the mitral position but none in the aortic position. Fluoroscopy can be used to visualize mobility of valve leaflets but is unable to identify thrombus/pannus formation that may be causing the

  8. The impact of beat-to-beat variability in optimising the acute hemodynamic response in cardiac resynchronisation therapy

    Directory of Open Access Journals (Sweden)

    Steven Niederer

    2015-12-01

    Conclusion: The beat-to-beat variation in AHR is significant in the context of CRT cut off values. A LOS optimisation offers a novel index to identify the optimal pacing site that accounts for both the mean and variation of the baseline measurement and pacing protocol.

  9. Beat-to-beat variability of QT intervals is increased in patients with drug-induced long-QT syndrome

    DEFF Research Database (Denmark)

    Hinterseer, Martin; Thomsen, Morten Bækgaard; Beckmann, Britt-Maria

    2008-01-01

    Torsades de pointes arrhythmias (TdP) occur by definition in the setting of prolonged QT intervals. Animal models of drug induced Long-QT syndrome (dLQTS) have shown higher predictive value for proarrhythmia with beat-to-beat variability of repolarization duration (BVR) when compared with QT inte...

  10. Prognostic Significance of Blood Pressure Variability on Beat-to-Beat Monitoring After Transient Ischemic Attack and Stroke.

    Science.gov (United States)

    Webb, Alastair J S; Mazzucco, Sara; Li, Linxin; Rothwell, Peter M

    2018-01-01

    Visit-to-visit and day-to-day blood pressure (BP) variability (BPV) predict an increased risk of cardiovascular events but only reflect 1 form of BPV. Beat-to-beat BPV can be rapidly assessed and might also be predictive. In consecutive patients within 6 weeks of transient ischemic attack or nondisabling stroke (Oxford Vascular Study), BPV (coefficient of variation) was measured beat-to-beat for 5 minutes (Finometer), day-to-day for 1 week on home monitoring (3 readings, 3× daily), and on awake ambulatory BP monitoring. BPV after 1-month standard treatment was related (Cox proportional hazards) to recurrent stroke and cardiovascular events for 2 to 5 years, adjusted for mean systolic BP. Among 520 patients, 26 had inadequate beat-to-beat recordings, and 22 patients were in atrial fibrillation. Four hundred five patients had all forms of monitoring. Beat-to-beat BPV predicted recurrent stroke and cardiovascular events independently of mean systolic BP (hazard ratio per group SD, stroke: 1.47 [1.12-1.91]; P =0.005; cardiovascular events: 1.41 [1.08-1.83]; P =0.01), including after adjustment for age and sex (stroke: 1.47 [1.12-1.92]; P =0.005) and all risk factors (1.40 [1.00-1.94]; P =0.047). Day-to-day BPV was less strongly associated with stroke (adjusted hazard ratio, 1.29 [0.97-1.71]; P =0.08) but similarly with cardiovascular events (1.41 [1.09-1.83]; P =0.009). BPV on awake ambulatory BP monitoring was nonpredictive (stroke: 0.89 [0.59-1.35]; P =0.59; cardiovascular events: 1.08 [0.77-1.52]; P =0.65). Despite a weak correlation ( r =0.119; P =0.02), beat-to-beat BPV was associated with risk of recurrent stroke independently of day-to-day BPV (1.41 [1.05-1.90]; P =0.02). Beat-to-beat BPV predicted recurrent stroke and cardiovascular events, independently of mean systolic BP and risk factors but short-term BPV on ambulatory BP monitoring did not. Beat-to-beat BPV may be a useful additional marker of cardiovascular risk. © 2017 The Authors.

  11. Diuretics as pathogenetic treatment for heart failure

    Science.gov (United States)

    Guglin, Maya

    2011-01-01

    Increased intracardiac filling pressure or congestion causes symptoms and leads to hospital admissions in patients with heart failure, regardless of their systolic function. A history of hospital admission, in turn, predicts further hospitalizations and morbidity, and a higher number of hospitalizations determine higher mortality. Congestion is therefore the driving force of the natural history of heart failure. Congestion is the syndrome shared by heart failure with preserved and reduced systolic function. These two conditions have almost identical morbidity, mortality, and survival because the outcomes are driven by congestion. A small difference in favor of heart failure with preserved systolic function comes from decreased ejection fraction and left ventricular remodeling which is only present in heart failure with decreased systolic function. The magnitude of this difference reflects the contribution of decreased systolic function and ventricular remodeling to the progression of heart failure. The only treatment available for congestion is fluid removal via diuretics, ultrafiltration, or dialysis. It is the only treatment that works equally well for heart failure with reduced and preserved systolic function because it affects congestion, the main pathogenetic feature of the disease. Diuretics are pathogenetic therapy for heart failure. PMID:21403798

  12. Biventricular capture verification by means of morphological analysis of intracardiac electrogram.

    Science.gov (United States)

    Lian, Jie; Garner, Garth; Muessig, Dirk

    2013-11-01

    The aim of this study is to develop a new feature for automatic biventricular capture verification in cardiac resynchronization therapy (CRT) devices, by means of morphological analysis of the intracardiac electrogram (IEGM). The algorithm performs capture classification based on a novel adaptive signed correlation index (ASCI), which measures morphological similarity between the post-pace IEGM and a template waveform representing captured paces. To evaluate the performance of the algorithm, CRT pacemakers were implanted in six dogs. During a mean follow-up of 23 days, 175 biventricular threshold tests were conducted with various configurations of pace/sense polarities. Biventricular IEGMs were recorded and downloaded for offline analysis. Template signals for each pace/sense configuration in each chamber were created for individual dogs during the first follow-up. Each pace was annotated for capture or non-capture by visual examination of the IEGM. A total of 9991 capture paces and 4474 non-capture paces were included for morphological analysis. The calculated ASCI values were well separated for capture and non-capture paces irrespective of right/left pacing chambers, pace/sense configurations, pacing amplitude, individual dogs, and temporal proximity of the capture templates. Overall, the classification accuracy of the algorithm remained ≥99% for any ASCI cut-off value choosing between 0.18 and 0.52. This study demonstrated the feasibility to perform automatic biventricular capture verification based on morphological analysis of the IEGM.

  13. Heart Health - Brave Heart

    Science.gov (United States)

    ... Bar Home Current Issue Past Issues Cover Story Heart Health Brave Heart Past Issues / Winter 2009 Table of Contents For ... you can have a good life after a heart attack." Lifestyle Changes Surviving—and thriving—after such ...

  14. Resting heart rate and cardiovascular events: risk factor or risk ...

    African Journals Online (AJOL)

    syndrome. In 139 194 patients with a non-ST-segment elevated acute coronary syndrome (NONSTEMI), a clear. J-shaped correlation was found between resting heart and all-cause mortality.5 The lowest mortality rate were in patients with resting heart rates between 50 and 70 beats per minute, but mortality doubled when ...

  15. Using a Phototransduction System to Monitor the Isolated Frog Heart

    Science.gov (United States)

    Stephens, Philip J.

    2015-01-01

    A simple and inexpensive method of monitoring the movement of an isolated frog heart provides comparable results to those obtained with a force transducer. A commercially available photoresistor is integrated into a Wheatstone bridge circuit, and the output signal is interfaced directly with a recording device. An excised, beating frog heart is…

  16. Study Heart Rate by Tools from Complex Networks

    International Nuclear Information System (INIS)

    Makowiec, D.; Wdowczyk-Szulc, J.; Zarczynska-Buchowiecka, M.; Gruchala, M.; Rynkiewicz, A.

    2011-01-01

    Heart rate measured as beat-to-beat time intervals varies in time. It is believed that time intervals between subsequent normal heart contractions carry information about the regulatory system of the heart. How to quantify such signals is not clear and because of that heart rate variability is still apart from the clinic routine. In the following, we propose a method for representing a heart rate signal as a directed network. Then we study the signal properties by complex network tools. The signals to study were collected from patients recovering after the heart transplantation. The aim is to classify the progress of adapting of the new heart - graft. Moreover, it is expected that the method allows for visual classification. Our investigations are preliminary, however the obtained results are promising. (authors)

  17. Psychoacoustic Factors in Musical Intonation: Beats, Interval Tuning, and Inharmonicity.

    Science.gov (United States)

    Keislar, Douglas Fleming

    Three psychoacoustic experiments were conducted using musically experienced subjects. In the first two experiments, the interval tested was the perfect fifth F4-C5; in the final one it was the major third F4-A4. The beat rate was controlled by two different methods: (1) simply retuning the interval, and (2) frequency-shifting one partial of each pair of beating partials without changing the overall interval tuning. The second method introduces inharmonicity. In addition, two levels of beat amplitude were introduced by using either a complete spectrum of 16 equal-amplitude partials per note, or by deleting one partial from each pair of beating partials. The results of all three experiments indicate that, for these stimuli, beating does not contribute significantly to the percept of "out-of-tuneness," because it made no difference statistically whether the beat amplitude was maximal or minimal. By contrast, mistuning the interval was highly significant. For the fifths, frequency-shifting the appropriate partials had about as much effect on the perceived intonation as mistuning the interval. For thirds, this effect was weaker, presumably since there were fewer inharmonic partials and they were higher in the harmonic series. Subjects were less consistent in their judgments of thirds than of fifths, perhaps because the equal-tempered and just thirds differ noticeably, unlike fifths. Since it is unlikely that beats would be more audible in real musical situations than under these laboratory conditions, these results suggest that the perception of intonation in music is dependent on the actual interval tuning rather than the concomitant beat rate. If beating partials are unimportant vis-a-vis interval tuning, this strengthens the argument for a cultural basis for musical intonation and scales, as opposed to the acoustical basis set forth by Helmholtz and others.

  18. Single-beat versus multibeat real-time 3D echocardiography for assessing left ventricular volumes and ejection fraction: a comparison study with cardiac magnetic resonance.

    Science.gov (United States)

    Macron, Laurent; Lim, Pascal; Bensaid, Alexandre; Nahum, Julien; Dussault, Caroline; Mitchell-Heggs, Laurens; Dubois-Randé, Jean-Luc; Deux, Jean-François; Gueret, Pascal

    2010-07-01

    Real-time 3-dimensional echocardiography (RT3DE) is superior to 2D echocardiography in assessing left ventricular (LV) volumes and ejection fraction (EF), but its feasibility is limited by multibeat acquisition, which requires an optimal breath-hold and a regular heart rhythm. We sought to evaluate the accuracy and feasibility of single- and 2-beat RT3DE for LV volume and EF assessment. Sixty-six consecutive patients referred for cardiac magnetic resonance (CMR) underwent RT3DE and CMR on the same day. Of the 50 patients (age, 59+/-18 years; 68%men; 42% coronary artery disease; LVEF=49+/-14%; limits, 14% to 76%) with an adequate RT3DE image quality, accuracy for LV volumes and EF measurements of single- and 2-beat modalities were compared with the conventional 4-beat acquisition and CMR. Correlations with CMR for LV end-diastolic volume (161+/-59 mL, r=0.93 to 0.94) and end-systolic volume (86+/-56 mL, r=0.93 to 0.96) were excellent regardless of the number of cardiac cycles used. However, because of the low temporal resolution (7+/-2 volumes per second), single-beat underestimated LVEF (bias, -5+/-8%) with greater bias than 2-beat (bias, 1+/-6%, P<0.001) and 4-beat (bias, 3+/-7%, P<0.001) modalities. Interestingly, 2-beat provided accuracy similar to 4-beat for end-diastolic volume (bias, -17+/-21 mL versus -15+/-23 mL), end-systolic volume (bias, -9+/-16 mL versus -12+/-17 mL), and LVEF (bias, 1+/-6% versus 3+/-7%) measurements, but fewer stitching artifacts were observed with 2- than 4-beat modalities (3% versus 30%). Compared with conventional multibeat acquisitions, 2-beat modality provides similar accuracy in LV volume and EF measurements and should be preferred due to fewer stitching artifacts. In contrast, the temporal resolution of single-beat modality appears insufficient to provide an accurate estimation of LVEF.

  19. Measuring and characterizing beat phenomena with a smartphone

    Science.gov (United States)

    Osorio, M.; Pereyra, C. J.; Gau, D. L.; Laguarda, A.

    2018-03-01

    Nowadays, smartphones are in everyone’s life. Apart from being excellent tools for work and communication, they can also be used to perform several measurements of simple physical magnitudes, serving as a mobile and inexpensive laboratory, ideal for use physics lectures in high schools or universities. In this article, we use a smartphone to analyse the acoustic beat phenomena by using a simple experimental setup, which can complement lessons in the classroom. The beats were created by the superposition of the waves generated by two tuning forks, with their natural frequencies previously characterized using different applications. After the characterization, we recorded the beats and analysed the oscillations in time and frequency.

  20. Generic flow profiles induced by a beating cilium.

    Science.gov (United States)

    Vilfan, A

    2012-08-01

    We describe a multipole expansion for the low-Reynolds-number fluid flows generated by a localized source embedded in a plane with a no-slip boundary condition. It contains 3 independent terms that fall quadratically with the distance and 6 terms that fall with the third power. Within this framework we discuss the flows induced by a beating cilium described in different ways: a small particle circling on an elliptical trajectory, a thin rod and a general ciliary beating pattern. We identify the flow modes present based on the symmetry properties of the ciliary beat.

  1. Left ventricular diastolic filling with an implantable ventricular assist device: beat to beat variability with overall improvement

    Science.gov (United States)

    Nakatani, S.; Thomas, J. D.; Vandervoort, P. M.; Zhou, J.; Greenberg, N. L.; Savage, R. M.; McCarthy, P. M.

    1997-01-01

    OBJECTIVES: We studied the effects of left ventricular (LV) unloading by an implantable ventricular assist device on LV diastolic filling. BACKGROUND: Although many investigators have reported reliable systemic and peripheral circulatory support with implantable LV assist devices, little is known about their effect on cardiac performance. METHODS: Peak velocities of early diastolic filling, late diastolic filling, late to early filling ratio, deceleration time of early filling, diastolic filling period and atrial filling fraction were measured by intraoperative transesophageal Doppler echocardiography before and after insertion of an LV assist device in eight patients. A numerical model was developed to simulate this situation. RESULTS: Before device insertion, all patients showed either a restrictive or a monophasic transmitral flow pattern. After device insertion, transmitral flow showed rapid beat to beat variation in each patient, from abnormal relaxation to restrictive patterns. However, when the average values obtained from 10 consecutive beats were considered, overall filling was significantly normalized from baseline, with early filling velocity falling from 87 +/- 31 to 64 +/- 26 cm/s (p assistance produced significant beat to beat variation in filling indexes, but overall a normalization of deceleration time as well as other variables. CONCLUSIONS: With LV assistance, transmitral flow showed rapidly varying patterns beat by beat in each patient, but overall diastolic filling tended to normalize with an increase of atrial contribution to the filling. Because of the variable nature of the transmitral flow pattern with the assist device, the timing of the device cycle must be considered when inferring diastolic function from transmitral flow pattern.

  2. "'Jackin’ for Beats'": DJing for Citation Critique

    Directory of Open Access Journals (Sweden)

    Todd Craig

    2013-10-01

    Full Text Available A challenge in teaching English composition is helping students envision plagiarism as “borrowing” – showing love to author(s and/or text(s that further their argument(s, versus “stealing” – biting someone’s style and words. Alastair Pennycook (1996 and Sarah Wakefield (2006 have contributed pieces to the elaborate plagiarism/citation puzzle, while Houston Baker situated the hip-hop DJ in seminal text Black Studies, Rap and the Academy (1993. Merging these moments introduces critical questions: Did Diddy invent “the remix” or become the illest beat-biter ever? How did DJ/Producers Pete Rock and Large Professor pay homage to previous musical genres to further hip-hop remix production without just taking 4-8 bar samples, copying sources and claiming unethical ownership? And how can this discussion provide students a window into citation conversations? This article will remix these “texts” to introduce the idea of DJ Rhetoric to discuss plagiarism. Through the lens of the hip-hop DJ in writing classrooms, one can foster an appreciation of the difference between “love and theft” in student citation. This article will couple examples from hip-hop music/culture while simultaneously remixing interviews from various hip-hop DJ/producers to help answer these difficult questions.

  3. Heart Rates of High School Physical Education Students during Team Sports, Individual Sports, and Fitness Activities

    Science.gov (United States)

    Laurson, Kelly R.; Brown, Dale D.; Cullen, Robert W.; Dennis, Karen K.

    2008-01-01

    This study examined how activity type influenced heart rates and time spent in target heart rate zones of high school students participating in physical education classes. Significantly higher average heart rates existed for fitness (142 plus or minus 24 beats per minute [bpm]) compared to team (118 plus or minus 24 bpm) or individual (114 plus or…

  4. MR imaging of the heart: functional imaging

    International Nuclear Information System (INIS)

    Croisille, P.; Revel, D.

    2000-01-01

    To date, most applications of cardiovascular MRI relate to the evaluation of major vessels rather than the heart itself. However, MRI plays a major role in the evaluation of specific types of cardiovascular pathology, namely intracardiac and paracardiac masses, pericardial disease, and congenital heart disease. In addition, because the visualization of cardiovascular anatomy with MR is non-invasive and permits three-dimensional analysis but also allows functional assessment of the cardiac pump, it is clear that MRI will have a growing and significant impact over the next years. We review some of the technical aspect of cardiac MRI and describe the current and potential clinical and investigative applications of this new methodology. (orig.)

  5. Nerve endings in the heart of teleosts.

    Science.gov (United States)

    Kumar, S

    1979-01-01

    The nerve endings in the heart of fishes were studied using silver impregnation techniques. The heart chambers are profusely innervated by the sympathetic, parasympathetic (vagal) and postganglionic fibers of the intracardiac ganglia situated at the sinuatrial and the atrioventricular junctions. The plexuses are composed of medullated and nonmedullated fibers. The nerve fibers generally end freely and are slightly branched or unbranched terminations of myelinated and unmyelinated fibers. Moreover, a few nerve fibers end redundant in the form of end-rings, bulb-like, bush-like, club-shaped end end-coil like structures. The complex unencapsulated types of endings are also found in the myocardium of the atrium and the ventricle. The encapsulated endings (Vater-Pacinian; Krause end-bulb) could not be observed.

  6. Resting heart rate, heart rate variability and functional decline in old age

    DEFF Research Database (Denmark)

    Ogliari, Giulia; Mahinrad, Simin; Stott, David J

    2015-01-01

    BACKGROUND: Heart rate and heart rate variability, markers of cardiac autonomic function, have been linked with cardiovascular disease. We investigated whether heart rate and heart rate variability are associated with functional status in older adults, independent of cardiovascular disease. METHODS......: We obtained data from the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER). A total of 5042 participants were included in the present study, and mean followup was 3.2 years. Heart rate and heart rate variability were derived from baseline 10-second electrocardiograms. Heart rate.......3 years. At baseline, higher heart rate was associated with worse ADL and IADL, and lower SDNN was related to worse IADL (all p values heart rate (range 71-117 beats/min) had a 1.79-fold (95% confidence interval [CI] 1.45-2.22) and 1.35-fold (95% CI 1...

  7. EARLY PRENATAL DIAGNOSTICS OF INBORN HEART DISEASES OF FETUSES WITH NUCHAL TRANSLUCENCY

    Directory of Open Access Journals (Sweden)

    E.A. Shevchenko

    2008-01-01

    Full Text Available The article represents an analysis of 38 events of inborn heart diseases of fetus with nuchal translucency, diagnosing on 11–16 weeks of pregnancy during consultative procedure. The spectrum of registered inborn heart diseases is represented by following nosologic forms: defect of interventricular partition, heart ectopy, atrioventricular canal, general arterial trunk, hypoplastic syndrome of the left sections of heart, fallot's tetrad, combination of defects of intracardiac partitions with diverticulum of ventricle. Frequency of registered inborn heart diseases and negative perinatal outcomes increased with the rise of thickness of nuchal translucency of fetus. transvaginal echocardiography with use of highly resolving ultra sonic equipment and new technology should be carried out in all cases of registration of widened nuchal translucency of fetus. It is decisive in improvement of diagnostics of inborn heart diseases, especially on early terms.Key words: inborn heart diseases, transvaginal echocardiography, prenatal diagnostics.

  8. Beat-to-beat P-wave morphology as a predictor of paroxysmal atrial fibrillation.

    Science.gov (United States)

    Filos, Dimitrios; Chouvarda, Ioanna; Tachmatzidis, Dimitris; Vassilikos, Vassilios; Maglaveras, Nicos

    2017-11-01

    Atrial Fibrillation (AF) is the most common cardiac arrhythmia. The initiation and the perpetuation of AF is linked with phenomena of atrial remodeling, referring to the modification of the electrical and structural characteristics of the atrium. P-wave morphology analysis can reveal information regarding the propagation of the electrical activity on the atrial substrate. The purpose of this study is to investigate patterns on the P-wave morphology that may occur in patients with Paroxysmal AF (PAF) and which can be the basis for distinguishing between PAF and healthy subjects. Vectorcardiographic signals in the three orthogonal axes (X, Y and Z), of 3-5 min duration, were analyzed during SR. In total 29 PAF patients and 34 healthy volunteers were included in the analysis. These data were divided into two distinct datasets, one for the training and one for the testing of the proposed approach. The method is based on the identification of the dominant and the secondary P-wave morphology by combining adaptive k-means clustering of morphologies and a beat-to-beat cross correlation technique. The P-waves of the dominant morphology were further analyzed using wavelet transform whereas time domain characteristics were also extracted. Following a feature selection step, a SVM classifier was trained, for the discrimination of the PAF patients from the healthy subjects, while its accuracy was tested using the independent testing dataset. In the cohort study, in both groups, the majority of the P-waves matched a main and a secondary morphology, while other morphologies were also present. The percentage of P-waves which simultaneously matched the main morphology in all three leads was lower in PAF patients (90.4 ± 7.8%) than in healthy subjects (95.5 ± 3.4%, p= 0.019). Three optimal scale bands were found and wavelet parameters were extracted which presented statistically significant differences between the two groups. Classification between the two groups was

  9. Human auditory steady state responses to binaural and monaural beats.

    Science.gov (United States)

    Schwarz, D W F; Taylor, P

    2005-03-01

    Binaural beat sensations depend upon a central combination of two different temporally encoded tones, separately presented to the two ears. We tested the feasibility to record an auditory steady state evoked response (ASSR) at the binaural beat frequency in order to find a measure for temporal coding of sound in the human EEG. We stimulated each ear with a distinct tone, both differing in frequency by 40Hz, to record a binaural beat ASSR. As control, we evoked a beat ASSR in response to both tones in the same ear. We band-pass filtered the EEG at 40Hz, averaged with respect to stimulus onset and compared ASSR amplitudes and phases, extracted from a sinusoidal non-linear regression fit to a 40Hz period average. A 40Hz binaural beat ASSR was evoked at a low mean stimulus frequency (400Hz) but became undetectable beyond 3kHz. Its amplitude was smaller than that of the acoustic beat ASSR, which was evoked at low and high frequencies. Both ASSR types had maxima at fronto-central leads and displayed a fronto-occipital phase delay of several ms. The dependence of the 40Hz binaural beat ASSR on stimuli at low, temporally coded tone frequencies suggests that it may objectively assess temporal sound coding ability. The phase shift across the electrode array is evidence for more than one origin of the 40Hz oscillations. The binaural beat ASSR is an evoked response, with novel diagnostic potential, to a signal that is not present in the stimulus, but generated within the brain.

  10. A quantitative electroencephalographic study of meditation and binaural beat entrainment.

    Science.gov (United States)

    Lavallee, Christina F; Koren, Stanley A; Persinger, Michael A

    2011-04-01

    The study objective was to determine the quantitative electroencephalographic correlates of meditation, as well as the effects of hindering (15 Hz) and facilitative (7 Hz) binaural beats on the meditative process. The study was a mixed design, with experience of the subject as the primary between-subject measure and power of the six classic frequency bands (δ, θ, low α, high α, β, γ), neocortical lobe (frontal, temporal, parietal, occipital), hemisphere (left, right), and condition (meditation only, meditation with 7-Hz beats, meditation with 15-Hz beats) as the within-subject measures. The study was conducted at Laurentian University in Sudbury, Ontario, Canada. The subjects comprised novice (mean of 8 months experience) and experienced (mean of 18 years experience) meditators recruited from local meditation groups. Experimental manipulation included application of hindering and facilitative binaural beats to the meditative process. Experienced meditators displayed increased left temporal lobe δ power when the facilitative binaural beats were applied, whereas the effect was not observed for the novice subjects in this condition. When the hindering binaural beats were introduced, the novice subjects consistently displayed more γ power than the experienced subjects over the course of their meditation, relative to baseline. Based on the results of this study, novice meditators were not able to maintain certain levels of θ power in the occipital regions when hindering binaural beats were presented, whereas when the facilitative binaural beats were presented, the experienced meditators displayed increased θ power in the left temporal lobe. These results suggest that the experienced meditators have developed techniques over the course of their meditation practice to counter hindering environmental stimuli, whereas the novice meditators have not yet developed those techniques.

  11. Utility of intracardiac ultrasound imaging to guide pulmonary vein ablation using laser balloon catheter.

    Science.gov (United States)

    Leite, Luiz; Su, Wilber; Johnson, Susan B; Milton, Mark; Henz, Benhur; Sarabanda, Alvaro; Santos, Simone N; Packer, Douglas L

    2009-12-01

    Pulmonary vein isolation (PVI) with balloon catheter has been used as the endpoint for AF ablation. To determine the usefulness of intracardiac ultrasound (ICUS) to guide PVI using laser balloon catheter. 59 PVs were ablated in 27 dogs. Doppler imaging was used to identify blood flow leaks between PV and balloon. After each energy delivery, the circular mapping catheter was repositioned to check if isolation had been achieved. The leak position was then correlated with the gap position at the pathological study. Multivariate logistic regression analysis was undertaken. 59 PV were ablated. Mean burn time was 279+/-177 sec, mean balloon diameter was 23+/-3 mm, and mean balloon length was 25+/-4 mm. Complete isolation was achieved in 38/59 (64%) cases, and it was significantly more common when there was no leak: [30/38 (79%) versus 8/23 (35%), p<0.001]. This occurred regardless of time of laser application (302+/-223 sec. vs. 266+/-148 sec., p=ns), laser power (3.5 W/cm, 4.5 W/cm, and 5.5 W/cm), balloon diameter (24+/- 3 mm vs. 22+/- 3 mm, p=ns) and length (27+/-4 mm vs. 24+/-4mm, p=ns). The positive predictive value for predicting incomplete isolation was 65% and the negative predictive value was 83%. An identifiable leak between PV and the LBA device seen at the ICUS is predictive of lower PV isolation rates. ICUS may be useful for leak detection to avoid ineffective energy application during circumferential PV ablation. This could also be helpful when other types of energy are used.

  12. Incidental intracardiac thromboemboli during liver transplantation: incidence, risk factors, and management.

    Science.gov (United States)

    Xia, Victor W; Ho, Jonathan K; Nourmand, Hamid; Wray, Christopher; Busuttil, Ronald W; Steadman, Randolph H

    2010-12-01

    Even though numerous cases of massive thromboemboli have been reported in the literature, intracardiac thromboemboli (ICTs) incidentally found during orthotopic liver transplantation (OLT) have not been examined. In this study, we retrospectively examined the incidence, risk factors, and management of incidental ICTs during OLT. After institutional review board approval, adult patients who underwent OLT between January 2004 and December 2008 at our center were reviewed. ICTs were identified and confirmed by the examination of OLT datasheets, anesthesia records, and recorded transesophageal echocardiography (TEE) clips. The clinical presentation, management, and outcomes of the patients with ICTs were reviewed. Risk factors were analyzed by multivariate logistic regression. During the study period, 426 of the 936 adult OLT patients (45.5%) underwent intraoperative TEE monitoring. Incidental ICTs were identified in 8 of these 426 patients (1.9%). Two ICTs occurred before reperfusion, and 6 ICTs occurred after reperfusion. The treatment was at the discretion of the treating physicians; however, none of the patients received an anticoagulant or thrombolytics. Multivariate analysis identified 2 independent risk factors for intraoperative incidental ICTs: the presence of symptomatic or surgically treated portal hypertension (a history of gastrointestinal bleeding, a transjugular intrahepatic portosystemic shunt procedure, or portocaval shunt surgery) before OLT and intraoperative hemodialysis (odds ratios of 4.05 and 7.29, respectively; P ICTs during OLT occurred at a rate of 1.9% and were associated with several preoperative and intraoperative risk factors. The use of TEE allows early identification, which may be important. Our management for incidental ICTs is described; however, no conclusions can be made about the optimal therapy. Copyright © 2010 American Association for the Study of Liver Diseases.

  13. Ivabradine: Heart Failure and Beyond.

    Science.gov (United States)

    Chaudhary, Rahul; Garg, Jalaj; Krishnamoorthy, Parasuram; Shah, Neeraj; Lanier, Gregg; Martinez, Mathew W; Freudenberger, Ronald

    2016-07-01

    Heart failure affects over 5 million people in the United States and carries a high rate of mortality. Ivabradine, a new agent has been added to the current medical options for managing heart failure. It is a selective funny current (If) inhibitor in sinoatrial node and slows its firing rate, prolonging diastolic depolarization without a negative inotropic effect. Ivabradine was only recently approved by Food and Drug administration after the results of Systolic Heart Failure Treatment with the If Inhibitor Ivabradine (SHIFT) trial, for a reduction in rehospitalizations from chronic heart failure. This trial assessed patients with stable heart failure with reduced ejection fraction and a heart rate of at least 70 beats per minute at rest on maximally tolerated beta-blocker therapy and demonstrated statistically significant reduction in heart failure hospitalization and deaths. Additionally, ivabradine has been associated with reduced cardiac remodeling, reduced heart rate variability, improvement in exercise tolerance, improved heart failure class of New York Heart Association, and better quality of life. It has also been tried in other conditions, such as inappropriate sinus tachycardia and cardiogenic shock, and is currently in phase II trial for patients with newly diagnosed multiple organ dysfunction syndrome. © The Author(s) 2015.

  14. Binaural auditory beats affect long-term memory.

    Science.gov (United States)

    Garcia-Argibay, Miguel; Santed, Miguel A; Reales, José M

    2017-12-08

    The presentation of two pure tones to each ear separately with a slight difference in their frequency results in the perception of a single tone that fluctuates in amplitude at a frequency that equals the difference of interaural frequencies. This perceptual phenomenon is known as binaural auditory beats, and it is thought to entrain electrocortical activity and enhance cognition functions such as attention and memory. The aim of this study was to determine the effect of binaural auditory beats on long-term memory. Participants (n = 32) were kept blind to the goal of the study and performed both the free recall and recognition tasks after being exposed to binaural auditory beats, either in the beta (20 Hz) or theta (5 Hz) frequency bands and white noise as a control condition. Exposure to beta-frequency binaural beats yielded a greater proportion of correctly recalled words and a higher sensitivity index d' in recognition tasks, while theta-frequency binaural-beat presentation lessened the number of correctly remembered words and the sensitivity index. On the other hand, we could not find differences in the conditional probability for recall given recognition between beta and theta frequencies and white noise, suggesting that the observed changes in recognition were due to the recollection component. These findings indicate that the presentation of binaural auditory beats can affect long-term memory both positively and negatively, depending on the frequency used.

  15. The Effects of Female Sex Hormones on Ventricular Premature Beats and Repolarization Parameters in Physiological Menstrual Cycle.

    Science.gov (United States)

    Dogan, Mehmet; Yiginer, Omer; Uz, Omer; Kucuk, Ugur; Degirmencioglu, Gokhan; Isilak, Zafer; Uzun, Mehmet; Davulcu, Ezgi

    2016-05-01

    The effects of gender difference on cardiac electrophysiology have been well studied. In this study, we aimed to evaluate the effects of estradiol and progesteron changes occuring in physiological menstrual cycle on ventricular premature beats (VPBs) and cardiac repolarization parameters. Women of reproductive age with VPBs were included into the study group and healthy women were recruited as the control group. During the menstruation period, a 12-lead electrocardiography, blood samples, and 24-hour rhythm Holter were applied to the study group. Similarly, all tests were repeated in the estimated ovulation period (12-14 days before menstruation) by all cases. The study group consisted of 20 women patients with VPB, and the control group of 18 healthy women. While the number of VPB in the menstruation period was 210 beats/day (interquartile range [IQR]: 1,144), it decreased to 86 beats/day (IQR: 251) in the ovulation period with statistical significance (P < 0.05). Average heart rate in the menstruation period was 81.4 ± 10 beats/min and it significantly increased to 84.6 ± 8 beats/min in the ovulation period (P < 0.05). There were no differences in cardiac repolarization parameters in both menstruation and ovulation periods between the study and control groups. Comparing the menstruation and the ovulation periods, J-Tpeak interval, which reflects early repolarization, was shorter in the ovulation period (193 ± 27.7 ms and 201.1 ± 28.6 ms, respectively; P < 0.05). Other repolarization parameters did not show any significant difference. VPB frequency decreases with estradiol peak in the ovulation period. This suggests that estrogen may have protective effects against ventricular arrhythmias. ©2016 Wiley Periodicals, Inc.

  16. Reversing blood flows act through klf2a to ensure normal valvulogenesis in the developing heart.

    Directory of Open Access Journals (Sweden)

    Julien Vermot

    2009-11-01

    Full Text Available Heart valve anomalies are some of the most common congenital heart defects, yet neither the genetic nor the epigenetic forces guiding heart valve development are well understood. When functioning normally, mature heart valves prevent intracardiac retrograde blood flow; before valves develop, there is considerable regurgitation, resulting in reversing (or oscillatory flows between the atrium and ventricle. As reversing flows are particularly strong stimuli to endothelial cells in culture, an attractive hypothesis is that heart valves form as a developmental response to retrograde blood flows through the maturing heart. Here, we exploit the relationship between oscillatory flow and heart rate to manipulate the amount of retrograde flow in the atrioventricular (AV canal before and during valvulogenesis, and find that this leads to arrested valve growth. Using this manipulation, we determined that klf2a is normally expressed in the valve precursors in response to reversing flows, and is dramatically reduced by treatments that decrease such flows. Experimentally knocking down the expression of this shear-responsive gene with morpholine antisense oligonucleotides (MOs results in dysfunctional valves. Thus, klf2a expression appears to be necessary for normal valve formation. This, together with its dependence on intracardiac hemodynamic forces, makes klf2a expression an early and reliable indicator of proper valve development. Together, these results demonstrate a critical role for reversing flows during valvulogenesis and show how relatively subtle perturbations of normal hemodynamic patterns can lead to both major alterations in gene expression and severe valve dysgenesis.

  17. Electrocardiogram: his bundle potentials can be recorded noninvasively beat by beat on surface electrocardiogram.

    Science.gov (United States)

    Wang, Gaopin; Liu, Renguang; Chang, Qinghua; Xu, Zhaolong; Zhang, Yingjie; Pan, Dianzhu

    2017-03-15

    The micro waveform of His bundle potential can't be recorded beat-to-beat on surface electrocardiogram yet. We have found that the micro-wavelets before QRS complex may be related to atrioventricular conduction system potentials. This study is to explore the possibility of His bundle potential can be noninvasively recorded on surface electrocardiogram. We randomized 65 patients undergoing radiofrequency catheter ablation of paroxysmal superventricular tachycardia (exclude overt Wolff-Parkinson-White syndrome) to receive "conventional electrocardiogram" and "new electrocardiogram" before the procedure. His bundle electrogram was collected during the procedure. Comparative analysis of PA s (PA interval recorded on surface electrocardiogram), AH s (AH interval recorded on surface electrocardiogram) and HV s (HV interval recorded on surface electrocardiogram) interval recorded on surface "new electrocardiogram" and PA, AH, HV interval recorded on His bundle electrogram was investigated. There was no difference (P > 0.05) between groups in HV s interval (49.63 ± 6.19 ms) and HV interval (49.35 ± 6.49 ms). Results of correlational analysis found that HV S interval was significantly positively associated with HV interval (r = 0.929; P electrocardiogram. Noninvasive His bundle potential tracing might represent a new method for locating the site of atrioventricular block and identifying the origin of a wide QRS complex.

  18. Intracardiac and intracerebral thrombosis associated with methylenetetrahydrofolate reductase A1298C homozygote mutation in paediatric steroidresistant nephrotic syndrome

    Directory of Open Access Journals (Sweden)

    Rahime Renda

    2016-12-01

    Full Text Available Thromboembolic complications are a significant cause of morbidity and mortality in cases of nephrotic syndrome. Hereditary thrombophilias are also known to increase vascular thrombosis. We present a case that has been followed up for steroid-resistant nephrotic syndrome (NS in which intracardiac and intracranial thrombosis subsequently developed. The patient was found to have a homozygote mutation in the methylenetetrahydrofolate reductase (MTHFR gene as an additional risk factor for recurrent thrombosis. MTHFR mutation with NS was considered to have an important effect on the development of life-threatening thrombosis.

  19. Intracardiac Eustachian Valve Cyst in an Adult Detected with Other Cardiac Anomalies: Usefulness of Multidetector CT in Diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Hyung Ji; Jung, Jung Im; Kim, Hwan Wook; Lee, Kyo Young [Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2012-07-15

    We present an unusual case of an intracardiac Eustachian valve cyst observed concurrently with atresia of the coronary sinus ostium, a persistent left superior vena cava (LSVC) and a bicuspid aortic valve. There have been several echocardiographic reports of Eustachian valve cysts; however, there is no report of multidetector computed tomography (MDCT) findings related to a Eustachian valve cyst. Recently, we observed a Eustachian valve cyst diagnosed on MDCT showing a hypodense cyst at the characteristic location of the Eustachian valve (the junction of the right atrium and inferior vena cava). MDCT also demonstrated additional cardiovascular anomalies including atresia of the coronary sinus ostium and a persistent LSVC and bicuspid aortic valve.

  20. Nitric oxide improves the hemodynamic performance of the hypoxic goldfish (Carassius auratus) heart

    DEFF Research Database (Denmark)

    Imbrogno, Sandra; Capria, C.; Tota, Bruno

    2014-01-01

    nitric oxide (NO) under normoxic and hypoxic conditions. Cardiac performance was examined both under basal (constant preload and afterload) and loading conditions, i.e. preload-induced increases in stroke volume (SV) and hence cardiac output at constant afterload (the Frank–Starling response). Hypoxic......Goldfish tolerate prolonged and severe hypoxia, thus representing a well-suited model to study the maintenance of cardiac function when O2 availability represents a limiting factor. Using a working heart preparation, we explored the role of the intracardiac nitric oxide synthase (NOS)- derived...... complemented by Western blotting analysis which revealed increased expressions of NOS and hypoxia inducible factor α(HIF-1α). In conclusion, we demonstrated that intracardiac NO/NOS enhances goldfish heart performance, remarkably expanding its hypoxic tolerance....

  1. Maternal heart rate changes during labour.

    Science.gov (United States)

    Söhnchen, N; Melzer, K; Tejada, B Martinez de; Jastrow-Meyer, N; Othenin-Girard, V; Irion, O; Boulvain, M; Kayser, B

    2011-10-01

    Labour and delivery represent a considerable effort for pregnant women. Lack of aerobic fitness may limit pushing efforts during childbirth and represents increased cardiovascular strain and risk. Increasing prevalence of sedentary behaviour and lack of aerobic fitness may reduce heart rate reserve during labour. We quantified maternal heart rate reserve (maximum heart rate minus resting heart rate) of 30 healthy pregnant women during labour and delivery and related it to habitual daily physical activity levels quantified during the third pregnancy trimester by the Pregnancy Physical Activity Questionnaire. Heart rates during labour reached values similar to those observed during moderate to heavy physical exercise. During active pushing one out of five women reached heart rates more than 90% of their heart rate reserve (188 ± 7 beats per min). Half of the women reached more than 70% of heart rate reserve (172 ± 14 beats per min). Physically inactive women used more of their heart rate reserve as physically more active women (87 ± 20% vs. 65 ± 12%, upper and lower tertile respectively, plabour is increased in physically inactive women and may potentially limit the intensity and duration of pushing efforts. Such higher cardiovascular strain in physically less active women may represent increased cardiovascular risk during labour. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  2. Reduced Dietary Sodium Intake Increases Heart Rate

    DEFF Research Database (Denmark)

    Graudal, Niels A; Hubeck-Graudal, Thorbjørn; Jürgens, Gesche

    2016-01-01

    Reduced dietary sodium intake (sodium reduction) increases heart rate in some studies of animals and humans. As heart rate is independently associated with the development of heart failure and increased risk of premature death a potential increase in heart rate could be a harmful side......-effect of sodium reduction. The purpose of the present meta-analysis was to investigate the effect of sodium reduction on heart rate. Relevant studies were retrieved from an updated pool of 176 randomized controlled trials (RCTs) published in the period 1973-2014. Sixty-three of the RCTs including 72 study...... populations reported data on heart rate. In a meta-analysis of these data sodium reduction increased heart rate with 1.65 beats per minute [95% CI: 1.19, 2.11], p sodium reduction...

  3. Scale Invariant Properties in Heart Rate Signals

    Science.gov (United States)

    Makowiec, D.; Dudkowska, A.; Zwierz, M.; Galaska, R.; Rynkiewicz, A.

    2006-05-01

    The rate of heart beat is controlled by autonomic nervous system: accelerated by the sympathetic system and slowed by the parasympathetic system. Scaling properties in heart rate are usually related to the intrinsic dynamics of this physiological regulatory system. The two packages calculating local exponent spectra: Wavelet Transform Modulus Maxima and Multifractal Detrended Fluctuation Analysis (accessible from Physionet home page http://circ.ahajournals.org/cgi/content/full/101/23/e215) are tested, and then used to investigate the spectrum of singularity exponents in series of heart rates obtained from patients suffering from reduced left ventricle systolic function. It occurs that this state of a heart could be connected to some perturbation in the regulatory system, because the heart rate appears to be less controlled than in a healthy human heart. The multifractality in the heart rate signal is weakened: the spectrum is narrower and moved to higher values what indicate the higher activity of the sympatethic nervous system.

  4. BIOPHYSICAL CHARACTERISATION OF THE UNDER-APPRECIATED AND IMPORTANT RELATIONSHIP BETWEEN HEART RATE VARIABILITY AND HEART RATE

    Science.gov (United States)

    Monfredi, Oliver; Lyashkov, Alexey E; Johnsen, Anne-Berit; Inada, Shin; Schneider, Heiko; Wang, Ruoxi; Nirmalan, Mahesh; Wisloff, Ulrik; Maltsev, Victor A; Lakatta, Edward G; Zhang, Henggui; Boyett, Mark R

    2014-01-01

    Heart rate variability (beat-to-beat changes in the RR interval) has attracted considerable attention over the last 30+ years (PubMed currently lists >17,000 publications). Clinically, a decrease in heart rate variability is correlated to higher morbidity and mortality in diverse conditions, from heart disease to foetal distress. It is usually attributed to fluctuation in cardiac autonomic nerve activity. We calculated heart rate variability parameters from a variety of cardiac preparations (including humans, living animals, Langendorff-perfused heart and single sinoatrial nodal cell) in diverse species, combining this with data from previously published papers. We show that regardless of conditions, there is a universal exponential decay-like relationship between heart rate variability and heart rate. Using two biophysical models, we develop a theory for this, and confirm that heart rate variability is primarily dependent on heart rate and cannot be used in any simple way to assess autonomic nerve activity to the heart. We suggest that the correlation between a change in heart rate variability and altered morbidity and mortality is substantially attributable to the concurrent change in heart rate. This calls for re-evaluation of the findings from many papers that have not adjusted properly or at all for heart rate differences when comparing heart rate variability in multiple circumstances. PMID:25225208

  5. Beating of wives: a cross-cultural perspective.

    Science.gov (United States)

    Campbell, J C

    1985-01-01

    This paper reports a more in-depth analysis of wife beating from a cross-cultural perspective. As background for the analysis, the methodological, operationalization, and measurement in previous cross-cultural research on wife beating is examined. Subsequently, a review of findings from these studies and the theoretical explanations from selected disciplines are presented as the basis of selection of variables expected to affect the presence and severity of wife abuse in a given culture. These variables are then examined with evidence from female perspective ethnographies on eleven different societies. This cross-cultural analysis of wife beating has illuminated more issues of methodology and variations of patterns than it has answered any questions about what may increase the frequency and severity of wife-beating in a given culture. It is possible that the beating of wives is a personal expression of hostility against women that may be expressed in addition to, or instead of, institutionalized aggression toward women in that culture. As such, wife beating can take many forms. It can be an indication of manhood, a means of personal control, a reflection of personal animosity, and an expression of sexual jealousy. These personal forms would be paralleled by societal expression such as gang rape, control of women by exclusion from the public sphere, general hostility between sexes, and the virtue of women becoming an issue of extended family and community honor. In conclusion, the importance of the variables is summarized and directions for future cross-cultural research on wife beating are suggested.

  6. Heart murmurs

    Science.gov (United States)

    Chest sounds - murmurs; Heart sounds - abnormal; Murmur - innocent; Innocent murmur; Systolic heart murmur; Diastolic heart murmur ... The heart has 4 chambers: Two upper chambers (atria) Two lower chambers (ventricles) The heart has valves that close ...

  7. Music and the heart.

    Science.gov (United States)

    Koelsch, Stefan; Jäncke, Lutz

    2015-11-21

    Music can powerfully evoke and modulate emotions and moods, along with changes in heart activity, blood pressure (BP), and breathing. Although there is great heterogeneity in methods and quality among previous studies on effects of music on the heart, the following findings emerge from the literature: Heart rate (HR) and respiratory rate (RR) are higher in response to exciting music compared with tranquilizing music. During musical frissons (involving shivers and piloerection), both HR and RR increase. Moreover, HR and RR tend to increase in response to music compared with silence, and HR appears to decrease in response to unpleasant music compared with pleasant music. We found no studies that would provide evidence for entrainment of HR to musical beats. Corresponding to the increase in HR, listening to exciting music (compared with tranquilizing music) is associated with a reduction of heart rate variability (HRV), including reductions of both low-frequency and high-frequency power of the HRV. Recent findings also suggest effects of music-evoked emotions on regional activity of the heart, as reflected in electrocardiogram amplitude patterns. In patients with heart disease (similar to other patient groups), music can reduce pain and anxiety, associated with lower HR and lower BP. In general, effects of music on the heart are small, and there is great inhomogeneity among studies with regard to methods, findings, and quality. Therefore, there is urgent need for systematic high-quality research on the effects of music on the heart, and on the beneficial effects of music in clinical settings. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  8. Heart Transplantation in Congenital Heart Disease: In Whom to Consider and When?

    Science.gov (United States)

    Attenhofer Jost, Christine H.; Schmidt, Dörthe; Huebler, Michael; Balmer, Christian; Noll, Georg; Caduff, Rosmarie; Greutmann, Matthias

    2013-01-01

    Due to impressive improvements in surgical repair options, even patients with complex congenital heart disease (CHD) may survive into adulthood and have a high risk of end-stage heart failure. Thus, the number of patients with CHD needing heart transplantation (HTx) has been increasing in the last decades. This paper summarizes the changing etiology of causes of death in heart failure in CHD. The main reasons, contraindications, and risks of heart transplantation in CHD are discussed and underlined with three case vignettes. Compared to HTx in acquired heart disease, HTx in CHD has an increased risk of perioperative death and rejection. However, outcome of HTx for complex CHD has improved over the past 20 years. Additionally, mechanical support options might decrease the waiting list mortality in the future. The number of patients needing heart-lung transplantation (especially for Eisenmenger's syndrome) has decreased in the last years. Lung transplantation with intracardiac repair of a cardiac defect is another possibility especially for patients with interatrial shunts. Overall, HTx will remain an important treatment option for CHD in the near future. PMID:23577237

  9. Detection of left atrial thrombus by intracardiac echocardiography in patients undergoing ablation of atrial fibrillation.

    Science.gov (United States)

    Sriram, Chenni S; Banchs, Javier E; Moukabary, Talal; Moradkhan, Raman; Gonzalez, Mario D

    2015-09-01

    The role of intracardiac echocardiography (ICE) to detect thrombus within left atrium (LA) before atrial fibrillation (AF) ablation despite a recent transesophageal echocardiogram (TEE) is not well defined. We examined the prevalence of LA/left atrial appendage (LAA) thrombus using ICE immediately prior to AF ablation in patients in whom anticoagulation was not withheld. We analyzed 122 consecutive patients (62.6 ± 10.8 years, 90 males, CHA(2)DS(2) -VASc score 2.4 ± 1.5, persistent AF 29.5 %) who underwent an ICE-guided AF ablation 1 day after a negative (n = 120) or inconclusive (n = 2) TEE for LA thrombus. LA was imaged with ICE from the right atrium, coronary sinus, and right ventricular inflow tract (RVIT). ICE and TEE images were compared for LAA area, thrombus, and spontaneous echo contrast (SEC). LAA was adequately visualized in 99 and 100 % of patients with TEE and ICE, respectively. RVIT was the best ICE view for LAA visualization. The LAA 2-D-area measured by TEE was 4.9 ± 0.5 vs. 5 ± 0.5 cm(2) by ICE (P = NS). ICE identified a thrombus in seven patients with a previous negative TEE, leading to cancellation of ablation. It ruled out a thrombus in two patients with an inconclusive TEE. Thrombi were found in the LAA (n = 4), atrial septum (n = 2), and left superior pulmonary vein (n = 1). SEC during TEE was more frequent in patients with thrombus on ICE than those without (85.7 vs. 17.4 %; p = 0.03; positive predictive value 23.1 %, negative predictive value 98.9 %). The results of our staged imaging approach suggest that ICE has a complimentary value in re-screening the LA/LAA for thrombus after a recent negative or equivocal TEE. The presence of SEC during TEE increases the probability of finding a thrombus with ICE, which could potentially be dislodged during catheter manipulation.

  10. Heart rate recovery and heart rate variability are unchanged in patients with coronary artery disease following 12 weeks of high-intensity interval and moderate-intensity endurance exercise training.

    Science.gov (United States)

    Currie, Katharine D; Rosen, Lee M; Millar, Philip J; McKelvie, Robert S; MacDonald, Maureen J

    2013-06-01

    Decreased heart rate variability and attenuated heart rate recovery following exercise are associated with an increased risk of mortality in cardiac patients. This study investigated the effects of 12 weeks of moderate-intensity endurance exercise (END) and a novel low-volume high-intensity interval exercise protocol (HIT) on measures of heart rate recovery and heart rate variability in patients with coronary artery disease (CAD). Fourteen males with CAD participated in 12 weeks of END or HIT training, each consisting of 2 supervised exercise sessions per week. END consisted of 30-50 min of continuous cycling at 60% peak power output (PPO). HIT involved ten 1-min intervals at 88% PPO separated by 1-min intervals at 10% PPO. Heart rate recovery at 1 min and 2 min was measured before and after training (pre- and post-training, respectively) using a submaximal exercise bout. Resting time and spectral and nonlinear domain measures of heart rate variability were calculated. Following 12 weeks of END and HIT, there was no change in heart rate recovery at 1 min (END, 40 ± 12 beats·min(-1) vs. 37 ± 19 beats·min(-1); HIT, 31 ± 8 beats·min(-1) vs. 35 ± 8 beats·min(-1); p ≥ 0.05 for pre- vs. post-training) or 2 min (END, 44 ± 18 beats·min(-1) vs. 43 ± 19 beats·min(-1); HIT, 42 ± 10 beats·min(-1) vs. 50 ± 6 beats·min(-1); p ≥ 0.05 for pre- vs. post-training). All heart rate variability indices were unchanged following END and HIT training. In conclusion, neither END nor HIT exercise programs elicited training-induced improvements in cardiac autonomic function in patients with CAD. The absence of improvements with training may be attributed to the optimal medical management and normative pretraining state of our sample.

  11. Mobile Intracardiac Mass after Inguinal Hernia Repair: An Unresolved Treatment Dilemma

    OpenAIRE

    Almehmadi, Fahad; Davis, Mark; Singh, Sheldon M.

    2015-01-01

    Right heart thrombi (RHT) are rare but well-described entity in literature. Their isolation has been considered as confirmatory for the diagnosis of venous thromboembolism (VTE). Even though their isolation aids the diagnosis, physicians are faced with a difficult management dilemma giving the paucity of data to support any treatment decision. We present a case of RHT in an 81-year-old man who presented to hospital with a large mobile right heart thrombus in transit seen on transthoracic echo...

  12. Continuing studies of the plasma beat wave accelerator

    International Nuclear Information System (INIS)

    Joshi, C.

    1990-01-01

    This is a proposal for the release of third year funds for the ''Plasma Beat Wave Accelerator'' program (PBWA) at UCLA under the direction of Professor C. Joshi. This report is also a summary of progress on this project since March 1990; i.e., the date of the last report to the DOE. Once again we note that although the program is for historical reasons called the Plasma Beat Wave Accelerator Program, our group is active in all areas of applications of lasers and plasmas in future high energy accelerators. These are as follows: heat gradient plasma structures; excited by plasma beat wave technique; laser wake field technique; and plasma wake field technique. Development of a photoinjector-driven, 20 MeV linac; and theoretical studies of the plasma lens and use of plasmas at the final focus

  13. Some nonlinear processes relevant to the beat wave accelerator

    International Nuclear Information System (INIS)

    Bingham, R.; Mori, W.B.

    1985-03-01

    The beat wave accelerator depends on the generation of a large amplitude plasma wave with a phase velocity close to the velocity of light c. The plasma wave (ωsub(p), ksub(p)) is generated by beating colinear laser beams (ω 1 , k 1 ) and (ω 2 ,k 2 ) with ωsub(p) = ω 1 -ω 2 , ksub(p) = k 1 -k 2 . Since the process involves both large amplitude transverse and longitudinal waves, various nonlinear instabilities associated with either wave may occur. The object of the article is to discuss some of the processes that may compete with the beat wave generation listing their threshold and growth rate. (author)

  14. Human sperm steer with second harmonics of the flagellar beat.

    Science.gov (United States)

    Saggiorato, Guglielmo; Alvarez, Luis; Jikeli, Jan F; Kaupp, U Benjamin; Gompper, Gerhard; Elgeti, Jens

    2017-11-10

    Sperm are propelled by bending waves traveling along their flagellum. For steering in gradients of sensory cues, sperm adjust the flagellar waveform. Symmetric and asymmetric waveforms result in straight and curved swimming paths, respectively. Two mechanisms causing spatially asymmetric waveforms have been proposed: an average flagellar curvature and buckling. We image flagella of human sperm tethered with the head to a surface. The waveform is characterized by a fundamental beat frequency and its second harmonic. The superposition of harmonics breaks the beat symmetry temporally rather than spatially. As a result, sperm rotate around the tethering point. The rotation velocity is determined by the second-harmonic amplitude and phase. Stimulation with the female sex hormone progesterone enhances the second-harmonic contribution and, thereby, modulates sperm rotation. Higher beat frequency components exist in other flagellated cells; therefore, this steering mechanism might be widespread and could inspire the design of synthetic microswimmers.

  15. Meta-analysis of validity of echogenic intracardiac foci for calculating the risk of Down syndrome in the second trimester of pregnancy

    Directory of Open Access Journals (Sweden)

    Ana María Rubio Lorente

    2017-02-01

    Full Text Available Echogenic intracardiac foci are a second trimester marker associated with aneuploidy in high-risk populations. The objective of this study is to assess the validity of echogenic intracardiac foci for Down syndrome detection in the second trimester ultrasound scan. A systematic search in major bibliographic databases was carried out (MEDLINE, EMBASE, CINAHL. Twenty-five studies about echogenic intracardiac foci were selected for statistical synthesis in this systematic review. Those 25 considered to be relevant were then subjected to critical reading, following the Critical Appraisal Skills Programme criteria, by at least three independent observers. Then, the published articles were subjected to a meta-analysis. A global sensitivity of 21.8% and a 4.1% false positive rate were obtained. The positive likelihood ratio was 5.08 (95% confidence interval, 4.04–6.41. The subgroups analysis did not reveal statistically significant differences. In conclusion, echogenic intracardiac foci as an isolated marker could be a tool to identify—rather than exclude—the high-risk group of Down syndrome, although it should be noted that it shows low sensitivity.

  16. Alfven Eigenmode excitation by ICRH beat-waves

    International Nuclear Information System (INIS)

    Fasoli, A.; Lister, J.B.; Dobbing, J.A.; Gormezano, C.; Jacquinot, J.; Sharapov, S.; Sibley, A.

    1995-08-01

    The resonant excitation of Alfven Eigenmodes by ICRH beat waves has been attempted experimentally on JET tokamak plasmas. Toroidicity induced AE are excited when the difference frequency between two ICRH antennas is of the order of the central frequency of the relative Alfven continuum gap. The relatively large amplitudes for the TAE driven ICRH beat waves suggest that this new non-linear excitation mechanism could allow investigations into the effects of AE on particle orbits and should be taken into account in ICRH heated thermonuclear plasmas. (author) 6 figs., 9 refs

  17. Cortical evoked potentials to an auditory illusion: Binaural beats

    OpenAIRE

    Pratt, H; Starr, A; Michalewski, HJ; Dimitrijevic, A; Bleich, N; Mittelman, N

    2009-01-01

    Objective: To define brain activity corresponding to an auditory illusion of 3 and 6 Hz binaural beats in 250 Hz or 1000 Hz base frequencies, and compare it to the sound onset response. Methods: Event-Related Potentials (ERPs) were recorded in response to unmodulated tones of 250 or 1000 Hz to one ear and 3 or 6 Hz higher to the other, creating an illusion of amplitude modulations (beats) of 3 Hz and 6 Hz, in base frequencies of 250 Hz and 1000 Hz. Tones were 2000 ms in duration and presented...

  18. Record Low β-beat of 10% in the LHC

    CERN Document Server

    Vanbavinckhove, G; Calaga, R; Miyamoto, R; Tomas, R

    2011-01-01

    During the 2011 LHC run several measurements and cor- rection campaigns were conducted. As a result a peak β- beat of 10% level was achieved. This level, well below the specified tolerances of the LHC, improves the aperture margins and helps minimize the luminosity imbalance be- tween the different experiments. A combination of local corrections at the insertion regions and an overall global correction were used to achieve this record low beta-beat. The sequence of the optics corrections and stability along the 2011 run are reported.

  19. The brain responses to different frequencies of binaural beat sounds on QEEG at cortical level.

    Science.gov (United States)

    Jirakittayakorn, Nantawachara; Wongsawat, Yodchanan

    2015-01-01

    Beat phenomenon is occurred when two slightly different frequency waves interfere each other. The beat can also occur in the brain by providing two slightly different frequency waves separately each ear. This is called binaural beat. The brain responses to binaural beat are in discussion process whether the brain side and the brain area. Therefore, this study aims to figure out the brain responses to binaural beat by providing different binaural beat frequencies on 250 carrier tone continuously for 30 minutes to participants and using quantitative electroencephalography (QEEG) to interpret the data. The result shows that different responses appear in different beat frequency. Left hemisphere dominance occur in 3 Hz beat within 15 minutes and 15 Hz beat within 5 minutes. Right hemisphere dominance occurs in 10 Hz beat within 25 minute. 6 Hz beat enhances all area of the brain within 10 minutes. 8 Hz and 25 Hz beats have no clearly responses while 40 Hz beat enhances the responses in frontal lobe. These brain responses can be used for brain modulation application to induce the brain activity in further studies.

  20. Zebrafish heart as a model to study the integrative autonomic control of pacemaker function

    Science.gov (United States)

    Stoyek, Matthew R.; Quinn, T. Alexander; Croll, Roger P.

    2016-01-01

    The cardiac pacemaker sets the heart's primary rate, with pacemaker discharge controlled by the autonomic nervous system through intracardiac ganglia. A fundamental issue in understanding the relationship between neural activity and cardiac chronotropy is the identification of neuronal populations that control pacemaker cells. To date, most studies of neurocardiac control have been done in mammalian species, where neurons are embedded in and distributed throughout the heart, so they are largely inaccessible for whole-organ, integrative studies. Here, we establish the isolated, innervated zebrafish heart as a novel alternative model for studies of autonomic control of heart rate. Stimulation of individual cardiac vagosympathetic nerve trunks evoked bradycardia (parasympathetic activation) and tachycardia (sympathetic activation). Simultaneous stimulation of both vagosympathetic nerve trunks evoked a summative effect. Effects of nerve stimulation were mimicked by direct application of cholinergic and adrenergic agents. Optical mapping of electrical activity confirmed the sinoatrial region as the site of origin of normal pacemaker activity and identified a secondary pacemaker in the atrioventricular region. Strong vagosympathetic nerve stimulation resulted in a shift in the origin of initial excitation from the sinoatrial pacemaker to the atrioventricular pacemaker. Putative pacemaker cells in the sinoatrial and atrioventricular regions expressed adrenergic β2 and cholinergic muscarinic type 2 receptors. Collectively, we have demonstrated that the zebrafish heart contains the accepted hallmarks of vertebrate cardiac control, establishing this preparation as a viable model for studies of integrative physiological control of cardiac function by intracardiac neurons. PMID:27342878

  1. Mobile Intracardiac Mass after Inguinal Hernia Repair: An Unresolved Treatment Dilemma.

    Science.gov (United States)

    Almehmadi, Fahad; Davis, Mark; Singh, Sheldon M

    2015-01-01

    Right heart thrombi (RHT) are rare but well-described entity in literature. Their isolation has been considered as confirmatory for the diagnosis of venous thromboembolism (VTE). Even though their isolation aids the diagnosis, physicians are faced with a difficult management dilemma giving the paucity of data to support any treatment decision. We present a case of RHT in an 81-year-old man who presented to hospital with a large mobile right heart thrombus in transit seen on transthoracic echocardiogram (TTE). He was successfully treated with anticoagulation alone. This case highlights the importance of TTE in establishing the diagnosis and describes the interplay of factors influencing treatment decision.

  2. Mobile Intracardiac Mass after Inguinal Hernia Repair: An Unresolved Treatment Dilemma

    Directory of Open Access Journals (Sweden)

    Fahad Almehmadi

    2015-01-01

    Full Text Available Right heart thrombi (RHT are rare but well-described entity in literature. Their isolation has been considered as confirmatory for the diagnosis of venous thromboembolism (VTE. Even though their isolation aids the diagnosis, physicians are faced with a difficult management dilemma giving the paucity of data to support any treatment decision. We present a case of RHT in an 81-year-old man who presented to hospital with a large mobile right heart thrombus in transit seen on transthoracic echocardiogram (TTE. He was successfully treated with anticoagulation alone. This case highlights the importance of TTE in establishing the diagnosis and describes the interplay of factors influencing treatment decision.

  3. Anatomy of the python heart.

    Science.gov (United States)

    Jensen, Bjarke; Nyengaard, Jens R; Pedersen, Michael; Wang, Tobias

    2010-12-01

    The hearts of all snakes and lizards consist of two atria and a single incompletely divided ventricle. In general, the squamate ventricle is subdivided into three chambers: cavum arteriosum (left), cavum venosum (medial) and cavum pulmonale (right). Although a similar division also applies to the heart of pythons, this family of snakes is unique amongst snakes in having intracardiac pressure separation. Here we provide a detailed anatomical description of the cardiac structures that confer this functional division. We measured the masses and volumes of the ventricular chambers, and we describe the gross morphology based on dissections of the heart from 13 ball pythons (Python regius) and one Burmese python (P. molurus). The cavum venosum is much reduced in pythons and constitutes approximately 10% of the cavum arteriosum. We suggest that shunts will always be less than 20%, while other studies conclude up to 50%. The high-pressure cavum arteriosum accounted for approximately 75% of the total ventricular mass, and was twice as dense as the low-pressure cavum pulmonale. The reptile ventricle has a core of spongious myocardium, but the three ventricular septa that separate the pulmonary and systemic chambers--the muscular ridge, the bulbuslamelle and the vertical septum--all had layers of compact myocardium. Pythons, however, have unique pads of connective tissue on the site of pressure separation. Because the hearts of varanid lizards, which also are endowed with pressure separation, share many of these morphological specializations, we propose that intraventricular compact myocardium is an indicator of high-pressure systems and possibly pressure separation.

  4. Intracardiac foreign body resulting from a transmediastinal gunshot mimics an extracardiac foreign body: An image presentation

    Directory of Open Access Journals (Sweden)

    Hsun-Yi Fu

    2017-10-01

    Full Text Available A transmediastinal gunshot wound (TMGW is one of the most severe traumatic injuries, with a high mortality rate. Prompt diagnosis and emergency surgical intervention with or without cardiopulmonary bypass are usually required to save lives. We report a particular case of TMGW in which the computed tomography imaging findings indicated an extracardiac foreign body. However, intraoperative findings revealed an intracardiac foreign body, and urgent cardiopulmonary bypass was performed to remove the foreign body. We suggest that cardiopulmonary bypass should be on standby during an exploratory sternotomy for TMGW, when the trajectory of the bullet hints at a cardiac-penetrating injury according to imaging studies and the location of the bullet remains unaffected by the patient's postural changes.

  5. Successful Management of Tubal Ectopic Pregnancy with Transvaginal Sonography Guided Intracardiac KCL Injection and Systemic Methotrexate - A Case Report

    Directory of Open Access Journals (Sweden)

    Sumesh Choudhary

    2014-01-01

    Full Text Available Background: Methotrexate (Mtx is an accepted modality for conservative treatment of ectopic pregnancy. However, there is no consensus regarding its use in live ectopic pregnancy and high serum beta-human chorionic gonadotrophin (β-hCG titres. Concurrent use of intra-sac hypertonic KCl, to produce cardiac asystole with systemic Mtx potentially improve outcome in live ectopic gestations with very high serum β-hCG titres. Here a successful management of live ectopic pregnancy in a 25-year-old nulliparous woman, with very high β-hCG titres (29502.04mIU/mL, using ultrasound-guided intra-cardiac potassium chloride (KCl injection and systemic Mtx is reported. No treatment related complications were encountered. However, individualized treatment with a stringent follow-up regime is mandatory in such cases.

  6. Uterine intravenous leiomyomatosis with intracardiac extension and pulmonary benign metastases on FDG PET/CT: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hui Chun; Wang, Yu Bin; Chen, Xiao Hong; Cu, Lan Lan [PET/CT Center, Gansu Provincial Hospital, Lanzhou (China)

    2016-04-15

    A 48-year-old woman presented with a 50-day history of irregular vaginal bleeding and lower abdominal pain. Ultrasound indicated an extremely large occupying lesion in the pelvic cavity that was highly suggestive of malignancy. Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) was performed to further assess the nature of pelvic abnormality. PET/CT images demonstrated a diffusely lobulated mass ranging from cervix up to the inferior pole of kidneys with mild FDG uptake. Simultaneously, multiple nodules in bilateral lungs and a hypodense lesion in the right ventricle were shown without FDG-avidity. Based on the imaging results, the presumptive diagnosis was uterine intravenous leiomyomatosis with intracardiac extension and pulmonary benign metastases, which was subsequently confirmed by MRI and the lesion biopsy.

  7. Extensive Intracardiac and Deep Venous Thromboses in a Young Woman with Heparin-Induced Thrombocytopenia and May-Thurner Syndrome

    Directory of Open Access Journals (Sweden)

    Yekaterina Kim

    2017-01-01

    Full Text Available A 38-year-old woman with a history of recurrent deep venous thromboses (DVTs on chronic anticoagulation presented with acute left leg swelling. The patient was diagnosed with an acute left lower extremity (LLE DVT in the setting of May-Thurner syndrome for which treatment with unfractionated heparin was started. Her hospital course was complicated by a new diagnosis of heparin-induced thrombocytopenia (HIT, with an incidental discovery of a large tricuspid valve mobile mass on a transthoracic echocardiogram (TTE. Subsequent imaging confirmed multiple right atrial thrombi along with LLE venous stent thrombosis and a new right LE acute DVT. Anticoagulation with argatroban for HIT thrombosis was started. She underwent a right atrial percutaneous thrombectomy and bilateral lower extremity thrombectomy with directed angioplasty and stent placement. This presentation is a rare manifestation of HIT with extensive intracardiac and deep venous thrombi, with successful staged interventions.

  8. Using Science and Much More to Beat the Flood

    Science.gov (United States)

    Seeley, Claire

    2014-01-01

    The Beat the Flood challenge involves designing and building a model flood-proof home, which is then tested in "flood" conditions. It is set on the fictitious Watu Island. The children form teams, with each team member being assigned a responsibility for the duration of the task--team leader, chief recorder, and resource manager. This…

  9. Wife beating amongst Africans as a challenge to pastoral care

    Directory of Open Access Journals (Sweden)

    Magezi E. Baloyi

    2013-11-01

    Full Text Available Traditional African people are known for respecting their marriage. Even though marriage is so highly regarded, it is astonishing to realise that wife beating has become an extremely common practice amongst them. It therefore becomes an important research question to ask about the extent to which deeply-seated traditional customs regarding wife beating as a form of stamping down authority and of trying to keep the household in order, will have to be confronted with what is deemed to be good practice from the perspective of the law, community and pastoral caregivers. There are women who live with scars on their faces and bodies, having been beaten by their husbands. Although there are many forms of abuse towards women in family situations, this article aims particularly to focus on wife beating that is practiced for traditional as well as other related reasons. This research will involve itself with establishing whether the reasons for wife beating are part of the traditional system for keeping the household in order and interrogate both legal and pastoral interventions that attempt to eliminate or avoid such behaviour.

  10. Efficiency of brainwave entrainment by binaural beats in reducing anxiety

    Directory of Open Access Journals (Sweden)

    Ahmad Alipoor

    2014-04-01

    Full Text Available Background: Anxiety is a fundamental phenomenon that is a common symptom in all mental disorders. The aim of the present study was to assess the effect of brainwave entrainment on anxiety reduction using binaural beats. Methods: In this experimental double-blind study, 30 employees were selected from an engineering research firm through random sampling and replacement and divided into two groups: control group and experimental group. All participants completed the Spielberger’s State-Trait Anxiety Inventory (STAI. Then, the experimental group listened to binaural beats which was recorded on a non-vocal piece of music for 4 weeks, 3 sessions each week. Each session lasted about 20 minutes. At the same time, the control group listened to the background music without any entrainment sound. At the end, both groups completed the anxiety questionnaire and the anxiety scores of both groups obtained before and after intervention were analyzed by ANCOVA. Results: The findings showed that the brainwave entrainment using binaural beats led to the significant reduction of state anxiety (P<0.001 and trait anxiety (P<0.018. Conclusion: Brainwave entrainment using binaural beats is an effective factor in decreasing state and trait anxiety; so, it can be used to reduce anxiety in mental health centers.

  11. Intimate partner abuse: wife beating among civil servants in Ibadan ...

    African Journals Online (AJOL)

    Wife beating is one of the most common forms of violence against women by husbands or other intimate male partners. Although violence against women is pervasive, there are only few studies documenting the magnitude of the problem especially among the working class. The civil service comprises of persons from all ...

  12. Beat-wave accelerator studies at the Rutherford Appleton Laboratory

    International Nuclear Information System (INIS)

    Lawson, J.D.

    1985-01-01

    The study carried out in 1982-83 at the Rutherford Appleton Laboratory to examine how one might use the beat-wave principle to construct a useful high energy accelerator is reviewed, and comments are made on later developments. A number of problems are evident to which solutions cannot at present be foreseen. (author)

  13. Popular Music in Southeast Asia : Banal Beats, Muted Histories

    NARCIS (Netherlands)

    Barendregt, Bart; Keppy, Peter; Schulte Nordholt, Henk

    2017-01-01

    'Popular Music in Southeast Asia: Banal Beats, Muted Histories' offers a cultural history of modern Southeast Asia from the original vantage point of popular music since the 1920s up to the present. By creatively connecting indigenous musical styles with foreign musical genres, Southeast Asians

  14. Beam cooling by using laser-undulator beat wave

    International Nuclear Information System (INIS)

    Kishimoto, Yasuaki; Tajima, Toshiki; Fisher, D.L.; Mima, Kunioki; Koga, J.

    1995-01-01

    Non-Hamiltonian manipulation of internal structure of phase space of charged particle beams can result in much faster cooling than the conventional stochastic cooling. The longitudinal emittance reduction is accomplished by the ponderomotive force of the beat between the undulator and the laser adjusted appropriate in its broadband spectrum through feedback at each turn. (author)

  15. An ethnic predilection for fetal echogenic intracardiac focus identified during targeted midtrimester ultrasound examination: A retrospective review

    Directory of Open Access Journals (Sweden)

    Monda Susan

    2004-06-01

    Full Text Available Abstract Background Echogenic intracardiac focus (EIF has been identified as a common ultrasound finding in association with fetal aneuploidy. Little is known about the association of this soft marker aneuploidy in various ethnic groups. Although it is commonly thought Asians in general have a higher incidence of EIF, it is unknown whether this also applies to Japanese as a subpopulation. The purpose of this study is to determine the antenatal incidence and postnatal significance of EIF observed during sonography in Japanese patients. Methods A cohort of Japanese patients who underwent ultrasound screening from 1997 to 1999 in the ultrasound unit at the New York University School of Medicine was identified. Variables included age, gestational age, serum markers, and the presence or absence of aneuploidy. Patients with first degree paternal or maternal Japanese ancestry were included for analysis. Examinations were performed between 14 and 24 weeks gestation. The prevalence of EIF was calculated. The control group was based on previously published data in the U.S (7.3% prevalence. Results A total of 154 subjects were identified, 148 were available for final analysis. Twenty-two fetuses had an EIF, 19 (86.4% left-sided, 3 (13.6% right-sided. Seventeen patients had other sonographic markers associated with aneuploidy. The mean maternal age at diagnosis was 30.7 ± 3.9 years and the mean gestational age was 19.8 ± 1.6 weeks. The prevalence of EIF was 14.8%. Compared to published population prevalence, there was a statistically significant difference (p Conclusion Asians of Japanese origin may have a higher prevalence of echogenic intracardiac foci, thus affecting the positive predictive value of this sonographic marker for aneuploidy.

  16. The role of pygopus in the differentiation of intra-cardiac valves in Drosophila

    Science.gov (United States)

    Tang, Min; Yuan, Wuzhou; Bodmer, Rolf; Wu, Xiushan; Ocorr, Karen

    2014-01-01

    Cardiac valves serve an important function; they support unidirectional blood flow and prevent blood regurgitation. Wnt signaling plays an important role in the formation of mouse cardiac valves and cardiac valve proliferation in Zebrafish, but identification of the specific signaling components involved has not been addressed systematically. Of the components involved in Wnt signal transduction, pygopus (pygo), first identified as a core component of Wnt signaling in Drosophila, has yet to be investigated with respect to valve development and differentiation. Here, we take advantage of the Drosophila heart model to study the role of pygo in formation of valves between the cardiac chambers. We found that cardiac-specific pygo knockdown in the Drosophila heart causes dilation in the region of these cardiac valves, and their characteristic dense mesh of myofibrils does not form and resembles that of neighboring cardiomyocytes. In contrast, heart-specific knockdown of the transcription factors, arm/β-Cat, lgs/BCL9 or pan/TCF, which mediate canonical Wnt signal transduction, shows a much weaker valve differentiation defect. Double-heterozygous combinations of mutants for pygo and the Wnt-signaling components have no additional effect on heart function compared to pygo heterozygotes alone. These results are consistent with the idea that pygo functions independently of canonical Wnt signaling in the differentiation of the adult inter-chamber cardiac valves. PMID:24265259

  17. [Frequency of heart tumors and their histopathological correlation].

    Science.gov (United States)

    Villalpando-Mendoza, Esteban; Pérez-Pérez, Francisco Manuel; Cortés-Flores, Ana Olivia; Velázquez-Ramírez, Gabriela Abigail; Fuentes-Orozco, Clotilde; González-Ojeda, Alejandro

    2006-01-01

    The presentation of heart tumors is very uncommon. Eighty percent of primary heart neoplasias are benign, and myxomas represent the first cause in frequency among adult populations. Due to the frequency of presentation of these tumors, it is common to make the clinical/surgical diagnosis without obtaining histopathologic confirmation. Our objective was to determine the frequency of presentation of heart tumors and its correlation between the surgical/clinical and histopathologic diagnosis in our Institute. This is a case series with 16 patients with cardiac tumors treated surgically at the Department of Cardiothoracic Surgery during a 4-year period. We used descriptive statistics, and quantitative variables are expressed as mean, range and standard deviation whereas qualitative variables were described as proportions. We included 3 men (19%) and 13 women (81%) with a mean age of 41.4 +/- 16.2 years. Clinical presentation was predominantly of congestive heart failure. Clinical diagnosis was determined in 15 patients (94%) and just one case of intracardiac thrombus (6%), whereas the histopathologic diagnosis reported myxoma in only 11 cases (68.8%), three patients with intra-cardiac thrombus (18.7%) and two patients with sarcomas (12.5%), leiomiosarcoma and angiosarcoma, respectively. We found a positive correlation between the clinical diagnosis and the histopathology results. There was no mortality. Even though myxomas represent the most frequent proportion of presentation in heart tumors, histopathological confirmation is necessary for diagnosis. Clinical and histopathologic correlation represents the basis for the choice of adequate management strategies and prognosis for the patient.

  18. Physiological importance of the coronary arterial blood supply to the rattlesnake heart

    DEFF Research Database (Denmark)

    Hagensen, Mette; Abe, Augusto S.; Falk, Erling

    2008-01-01

    Pa and 58.2±2.2 beats min-1, respectively, during activity and the ECG was not affected. This was not different from sham-operated snakes. Thus, while the outer compact layer of the rattlesnake heart clearly has an extensive coronary supply, rattlesnakes sustain a high blood pressure and heart rate during...

  19. What makes a rhythm complex? The influence of musical training and accent type on beat perception

    NARCIS (Netherlands)

    Bouwer, F.L.; Burgoyne, J.A.; Odijk, D.; Honing, H.; Grahn, J.A.

    2018-01-01

    Perception of a regular beat in music is inferred from different types of accents. For example, increases in loudness cause intensity accents, and the grouping of time intervals in a rhythm creates temporal accents. Accents are expected to occur on the beat: when accents are “missing” on the beat,

  20. Normal Values for Heart Electrophysiology Parameters of Healthy Swine Determined on Electrophysiology Study.

    Science.gov (United States)

    Noszczyk-Nowak, Agnieszka; Cepiel, Alicja; Janiszewski, Adrian; Pasławski, Robert; Gajek, Jacek; Pasławska, Urszula; Nicpoń, Józef

    2016-01-01

    Swine are a well-recognized animal model for human cardiovascular diseases. Despite the widespread use of porcine model in experimental electrophysiology, still no reference values for intracardiac electrical activity and conduction parameters determined during an invasive electrophysiology study (EPS) have been developed in this species thus far. The aim of the study was to develop a set of normal values for intracardiac electrical activity and conduction parameters determined during an invasive EPS of swine. The study included 36 healthy domestic swine (24-40 kg body weight). EPS was performed under a general anesthesia with midazolam, propofol and isoflurane. The reference values for intracardiac electrical activity and conduction parameters were calculated as arithmetic means ± 2 standard deviations. The reference values were determined for AH, HV and PA intervals, interatrial conduction time at its own and imposed rhythm, sinus node recovery time (SNRT), corrected sinus node recovery time (CSNRT), anterograde and retrograde Wenckebach points, atrial, atrioventricular node and ventricular refractory periods. No significant correlations were found between body weight and heart rate of the examined pigs and their electrophysiological parameters. The hereby presented reference values can be helpful in comparing the results of various studies, as well as in more accurately estimating the values of electrophysiological parameters that can be expected in a given experiment.

  1. Camera-cinematography of the heart

    International Nuclear Information System (INIS)

    Adam, W.E.; Meyer, G.; Bitter, F.; Kampmann, H.; Bargon, G.; Stauch, M.; Ulm Univ.

    1975-01-01

    By 'camera-cinematography' of the heart, we mean an isotope method which permits detailed observation of cardiac mechanics without the use of a catheter. All that is necessary is an intravenous injection of 10 to 15 mCisup(99m)Tc human serum albumin followed after ten minutes by a five to ten minute period of observation with a scintillation camera. At this time the isotope has become distributed in the blood. Variations in the precordial impulses correspond with intra-cardiac changes of blood volume during a cardiac cycle. Analysis of the R-wave provides adequate information of cyclical volume changes in limited portions of the heart. This is achieved by a monitor with a pseudo-3-dimensional display; contraction and relaxation of the myocardium can be shown for any chosen longitudinal or horizontal diameter of the heart. Our programme allows simultaneous presentation of the movement of any point on the myocardium as a time-activity curve. The method is recommended as an addition to chest radiography, heart screening or cardiac kymography before carrying out cardiac catheterisation. (orig.) [de

  2. Cardiac magnetic resonance imaging in patients with congenital heart disease; Kardiale MRT bei Patienten mit angeborenen Herzfehlern

    Energy Technology Data Exchange (ETDEWEB)

    Kreitner, Karl-Friedrich [Mainz Univ. Universitaetsmedizin Mainz (Germany). Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie; Kaufmann, Lilly [Mainz Univ. (Germany); Sorantin, Erich [Univ.-Klinik fuer Radiologie, Graz (Austria). Klinische Abt. fuer Kinderradiologie

    2015-06-15

    The prevalence of congenital heart disease (CHD) is around 10 per 1000 live births in Germany. More than 90 % of these patients will survive into adulthood due to improvements in therapy. The classification of CHD may be based according to the anatomic structures involved, to the presence of an intracardiac shunt, the presence of a cyanosis and the intensity of therapy and complexity of the disease. Nearly half of all patients with CHD suffer from an intracardiac shunt, whereas complex cases such as patients with a tetralogy of Fallot or transposition of the great arteries are much more rare. Cardiac magnetic resonance imaging plays an important role in the work-up and follow-up of patients with CHD, especially after infancy and childhood. Depending on the abnormality in question, a multiparametric examination protocol is mandatory. Knowledge of operative procedures and findings of other imaging modalities help to optimize examination and time needed for it.

  3. Effect of oxygen treatment on heart rate after abdominal surgery

    DEFF Research Database (Denmark)

    Rosenberg-Adamsen, S; Lie, C; Bernhard, A

    1999-01-01

    BACKGROUND: Cardiac complications are common during the postoperative period and may be associated with hypoxemia and tachycardia. Preliminary studies in high-risk patients after operation have shown a possible beneficial effect of oxygen therapy on arterial oxygen saturation and heart rate....... METHODS: The authors studied the effect of oxygen therapy on arterial oxygen saturation and heart rate in 100 consecutive unselected patients randomly and double blindly allocated to receive air or oxygen therapy between the first and fourth day after major abdominal surgery. RESULTS: The median arterial...... oxygen saturation rate increased significantly from 96% to 99% (P heart rate decreased significantly from 85 beats/min to 81 beats/min (P heart rate occurred...

  4. Mitral valve m-mode echo in complete heart block with atrial tachycardia

    Directory of Open Access Journals (Sweden)

    Kalathingathodika Sajeer

    2013-01-01

    Full Text Available We report a 48-year-old man who presented with history of syncope. Electrocardiogram on admission showed infrahisian complete heart block with a ventricular rate of 36 beats per min with wide QRS junctional escape and atrial rate was 188 beats per min. Transthoracic echocardiogram showed fine vibratory movement of both mitral leaflet tips. M-mode evaluation of mitral leaflets showed multiple ′a′ waves corresponding to atrial tachycardia rate.

  5. Loss of lag-response curvilinearity of indices of heart rate variability in congestive heart failure

    Directory of Open Access Journals (Sweden)

    Smith Michael L

    2006-06-01

    Full Text Available Abstract Background Heart rate variability (HRV is known to be impaired in patients with congestive heart failure (CHF. Time-domain analysis of ECG signals traditionally relies heavily on linear indices of an essentially non-linear phenomenon. Poincaré plots are commonly used to study non-linear behavior of physiologic signals. Lagged Poincaré plots incorporate autocovariance information and analysis of Poincaré plots for various lags can provide interesting insights into the autonomic control of the heart. Methods Using Poincaré plot analysis, we assessed whether the relation of the lag between heart beats and HRV is altered in CHF. We studied the influence of lag on estimates of Poincaré plot indices for various lengths of beat sequence in a public domain data set (PhysioNet of 29 subjects with CHF and 54 subjects with normal sinus rhythm. Results A curvilinear association was observed between lag and Poincaré plot indices (SD1, SD2, SDLD and SD1/SD2 ratio in normal subjects even for a small sequence of 50 beats (p value for quadratic term 3 × 10-5, 0.002, 3.5 × 10-5 and 0.0003, respectively. This curvilinearity was lost in patients with CHF even after exploring sequences up to 50,000 beats (p values for quadratic term > 0.5. Conclusion Since lagged Poincaré plots incorporate autocovariance information, these analyses provide insights into the autonomic control of heart rate that is influenced by the non-linearity of the signal. The differences in lag-response in CHF patients and normal subjects exist even in the face of the treatment received by the CHF patients.

  6. Identification of the impact direction using the beat signals detected by piezoceramic sensors

    Science.gov (United States)

    Huo, Linsheng; Li, Xu; Chen, Dongdong; Li, Hongnan; Song, Gangbing

    2017-08-01

    The beat phenomenon may be observed in a free vibration test with piezoceramic sensors. In contrast to exponential decay vibration, the beat signal is characterized as decreasing or increasing periodically. The beat phenomenon in the piezoelectric sensors is caused by the combination of signals of an oblique impact coming from two orthogonal directions of structures. An impact direction determination method based on the beat signal is proposed in this paper. The proposed method was verified through an impact test on a steel column specimen. The results showed that the proposed method can effectively identify the impact direction by using the envelope of the beat signal of the piezoelectric sensor.

  7. Cardiac CT angiography in children with congenital heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Siripornpitak, Suvipaporn, E-mail: ssiripornpitak@yahoo.com [Division of Diagnostic Radiology, Department of Diagnostic and Therapeutic Radiology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok (Thailand); Pornkul, Ratanaporn [Division of Diagnostic Radiology, Department of Diagnostic and Therapeutic Radiology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok (Thailand); Khowsathit, Pongsak [Pediatric Cardiac Unit, Department of Pediatrics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok (Thailand); Layangool, Thanarat; Promphan, Worakan [Pediatric Cardiology Unit, Queen Sirikit National Institute of Child Health, Bangkok (Thailand); Pongpanich, Boonchob [Pediatric Cardiac Unit, Department of Pediatrics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok (Thailand)

    2013-07-15

    Cardiac imaging plays an important role in both congenital and acquired heart diseases. Cardiac computed tomography (angiography) cCT(A) is a non-invasive, increasingly popular, complementary modality to echocardiography in evaluation of congenital heart diseases (CHD) in children. Despite radiation exposure, cCT(A) is now commonly used for evaluation of the complex CHD, giving information of both intra-cardiac and extra-cardiac anatomy, coronary arteries, and vascular structures. This review article will focus on the fundamentals and essentials for performing cCT(A) in children, including radiation dose awareness, basic techniques, and strengths and weaknesses of cCT(A) compared with cardiac magnetic resonance imaging (cMRI), and applications. The limitations of this modality will also be discussed, including the CHD for which cMRI may be substituted.

  8. Heart Failure

    Science.gov (United States)

    Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. Heart failure does not mean that your heart has stopped ... and shortness of breath Common causes of heart failure are coronary artery disease, high blood pressure and ...

  9. The Effect of Binaural Beats on Visuospatial Working Memory and Cortical Connectivity.

    Science.gov (United States)

    Beauchene, Christine; Abaid, Nicole; Moran, Rosalyn; Diana, Rachel A; Leonessa, Alexander

    2016-01-01

    Binaural beats utilize a phenomenon that occurs within the cortex when two different frequencies are presented separately to each ear. This procedure produces a third phantom binaural beat, whose frequency is equal to the difference of the two presented tones and which can be manipulated for non-invasive brain stimulation. The effects of binaural beats on working memory, the system in control of temporary retention and online organization of thoughts for successful goal directed behavior, have not been well studied. Furthermore, no studies have evaluated the effects of binaural beats on brain connectivity during working memory tasks. In this study, we determined the effects of different acoustic stimulation conditions on participant response accuracy and cortical network topology, as measured by EEG recordings, during a visuospatial working memory task. Three acoustic stimulation control conditions and three binaural beat stimulation conditions were used: None, Pure Tone, Classical Music, 5Hz binaural beats, 10Hz binaural beats, and 15Hz binaural beats. We found that listening to 15Hz binaural beats during a visuospatial working memory task not only increased the response accuracy, but also modified the strengths of the cortical networks during the task. The three auditory control conditions and the 5Hz and 10Hz binaural beats all decreased accuracy. Based on graphical network analyses, the cortical activity during 15Hz binaural beats produced networks characteristic of high information transfer with consistent connection strengths throughout the visuospatial working memory task.

  10. The Effect of Binaural Beats on Visuospatial Working Memory and Cortical Connectivity.

    Directory of Open Access Journals (Sweden)

    Christine Beauchene

    Full Text Available Binaural beats utilize a phenomenon that occurs within the cortex when two different frequencies are presented separately to each ear. This procedure produces a third phantom binaural beat, whose frequency is equal to the difference of the two presented tones and which can be manipulated for non-invasive brain stimulation. The effects of binaural beats on working memory, the system in control of temporary retention and online organization of thoughts for successful goal directed behavior, have not been well studied. Furthermore, no studies have evaluated the effects of binaural beats on brain connectivity during working memory tasks. In this study, we determined the effects of different acoustic stimulation conditions on participant response accuracy and cortical network topology, as measured by EEG recordings, during a visuospatial working memory task. Three acoustic stimulation control conditions and three binaural beat stimulation conditions were used: None, Pure Tone, Classical Music, 5Hz binaural beats, 10Hz binaural beats, and 15Hz binaural beats. We found that listening to 15Hz binaural beats during a visuospatial working memory task not only increased the response accuracy, but also modified the strengths of the cortical networks during the task. The three auditory control conditions and the 5Hz and 10Hz binaural beats all decreased accuracy. Based on graphical network analyses, the cortical activity during 15Hz binaural beats produced networks characteristic of high information transfer with consistent connection strengths throughout the visuospatial working memory task.

  11. Auditory beat stimulation and its effects on cognition and mood states

    Directory of Open Access Journals (Sweden)

    Leila eChaieb

    2015-05-01

    Full Text Available Auditory beat stimulation may be a promising new tool for the manipulation of cognitive processes and the modulation of mood-states. Here we aim to review the literature examining the most current applications of auditory beat stimulation and its targets. We give a brief overview of research on auditory steady-state responses and its relationship to auditory beat stimulation. We have summarized relevant studies investigating the neurophysiological changes related to auditory beat stimulation and how they impact upon the design of appropriate stimulation protocols. Focusing on binaural beat stimulation, we then discuss the role of monaural and binaural beat frequencies in cognition and mood-states, in addition to their efficacy in targeting disease symptoms. We aim to highlight important points concerning stimulation parameters and try to address why there are often contradictory findings with regard to the outcomes of auditory beat stimulation.

  12. Ultrafast quantum beats of anisotropic excitons in atomically thin ReS2.

    Science.gov (United States)

    Sim, Sangwan; Lee, Doeon; Trifonov, Artur V; Kim, Taeyoung; Cha, Soonyoung; Sung, Ji Ho; Cho, Sungjun; Shim, Wooyoung; Jo, Moon-Ho; Choi, Hyunyong

    2018-01-24

    Quantum beats, periodic oscillations arising from coherent superposition states, have enabled exploration of novel coherent phenomena. Originating from strong Coulomb interactions and reduced dielectric screening, two-dimensional transition metal dichalcogenides exhibit strongly bound excitons either in a single structure or hetero-counterpart; however, quantum coherence between excitons is barely known to date. Here we observe exciton quantum beats in atomically thin ReS 2 and further modulate the intensity of the quantum beats signal. Surprisingly, linearly polarized excitons behave like a coherently coupled three-level system exhibiting quantum beats, even though they exhibit anisotropic exciton orientations and optical selection rules. Theoretical studies are also provided to clarify that the observed quantum beats originate from pure quantum coherence, not from classical interference. Furthermore, we modulate on/off quantum beats only by laser polarization. This work provides an ideal laboratory toward polarization-controlled exciton quantum beats in two-dimensional materials.

  13. Recovery of spray paint traces from clothing by beating.

    Science.gov (United States)

    Olderiks, Maurice; Baiker, Martin; van Velzen, Jill; van der Weerd, Jaap

    2015-03-01

    Manual recovery of spray paints from textiles using a microscope, the routine method in many laboratories, is often laborious. Beating the clothing with a plastic rod, the routine method used for recovery of glass traces within the authors' laboratory, is proposed as an alternative. The efficiency of the method was evaluated by spray tests with fluorescent paint. In these tests, paint particles in the acquired debris samples, as well as those remaining on the textiles, were investigated. The results show that beating is an efficient way to recover and concentrate paint particles. A good efficiency for jeans fabric and rough knitwear is reported. The results appeared to be less satisfactory for smooth woven fabric. Application of the method in casework was effective for graffiti paints as well as for flaked car paint. © 2014 American Academy of Forensic Sciences.

  14. Nonlinear beat excitation of low frequency wave in degenerate plasmas

    Science.gov (United States)

    Mir, Zahid; Shahid, M.; Jamil, M.; Rasheed, A.; Shahbaz, A.

    2018-03-01

    The beat phenomenon due to the coupling of two signals at slightly different frequencies that generates the low frequency signal is studied. The linear dispersive properties of the pump and sideband are analyzed. The modified nonlinear dispersion relation through the field coupling of linear modes against the beat frequency is derived in the homogeneous quantum dusty magnetoplasmas. The dispersion relation is used to derive the modified growth rate of three wave parametric instability. Moreover, significant quantum effects of electrons through the exchange-correlation potential, the Bohm potential, and the Fermi pressure evolved in macroscopic three wave interaction are presented. The analytical results are interpreted graphically describing the significance of the work. The applications of this study are pointed out at the end of introduction.

  15. Measuring of beat up force on weaving machines

    Directory of Open Access Journals (Sweden)

    Bílek Martin

    2017-01-01

    Full Text Available The textile material (warp is stressed cyclically at a relative high frequency during the weaving process. Therefore, the special measuring device for analysis of beat up force in the textile material during the weaving process, has been devised in the Weaving Laboratory of the TUL. This paper includes a description of this measuring device. The experimental part includes measurements results for various materials (PES and VS and various warp thread densities of the produced fabric.

  16. Effectiveness of binaural beats in reducing preoperative dental anxiety.

    Science.gov (United States)

    Isik, B K; Esen, A; Büyükerkmen, B; Kilinç, A; Menziletoglu, D

    2017-07-01

    Binaural beats are an auditory illusion perceived when two different pure-tone sine waves are presented one to each ear at a steady intensity and frequency. We evaluated their effectiveness in reducing preoperative anxiety in dentistry. Sixty patients (30 in each group) who were to have impacted third molars removed were studied (experimental group: 20 women and 10 men, mean (range) age 24 (18-35) years, and control group: 22 women and 8 men, mean (range) age 28 (15-47) years). All patients were fully informed about the operation preoperatively, and their anxiety recorded on a visual analogue scale (VAS). The local anaesthetic was given and the patients waited for 10minutes, during which those in the experimental group were asked to listen to binaural beats through stereo earphones (200Hz for the left ear and 209.3Hz for the right ear). No special treatment was given to the control group. In both groups anxiety was then recorded again, and the tooth removed in the usual way. The paired t test and t test were used to assess the significance of differences between groups. The degree of anxiety in the control group was unchanged after the second measurement (p=0.625), while that in the experimental group showed a significant reduction in anxiety (p=0.001). We conclude that binaural beats may be useful in reducing preoperative anxiety in dentistry. Copyright © 2017 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  17. Transplantation of Hearts Donated after Circulatory Death

    Directory of Open Access Journals (Sweden)

    Christopher W. White

    2018-02-01

    Full Text Available Cardiac transplantation has become limited by a critical shortage of suitable organs from brain-dead donors. Reports describing the successful clinical transplantation of hearts donated after circulatory death (DCD have recently emerged. Hearts from DCD donors suffer significant ischemic injury prior to organ procurement; therefore, the traditional approach to the transplantation of hearts from brain-dead donors is not applicable to the DCD context. Advances in our understanding of ischemic post-conditioning have facilitated the development of DCD heart resuscitation strategies that can be used to minimize ischemia-reperfusion injury at the time of organ procurement. The availability of a clinically approved ex situ heart perfusion device now allows DCD heart preservation in a normothermic beating state and minimizes exposure to incremental cold ischemia. This technology also facilitates assessments of organ viability to be undertaken prior to transplantation, thereby minimizing the risk of primary graft dysfunction. The application of a tailored approach to DCD heart transplantation that focuses on organ resuscitation at the time of procurement, ex situ preservation, and pre-transplant assessments of organ viability has facilitated the successful clinical application of DCD heart transplantation. The transplantation of hearts from DCD donors is now a clinical reality. Investigating ways to optimize the resuscitation, preservation, evaluation, and long-term outcomes is vital to ensure a broader application of DCD heart transplantation in the future.

  18. Transplantation of Hearts Donated after Circulatory Death

    Science.gov (United States)

    White, Christopher W.; Messer, Simon J.; Large, Stephen R.; Conway, Jennifer; Kim, Daniel H.; Kutsogiannis, Demetrios J.; Nagendran, Jayan; Freed, Darren H.

    2018-01-01

    Cardiac transplantation has become limited by a critical shortage of suitable organs from brain-dead donors. Reports describing the successful clinical transplantation of hearts donated after circulatory death (DCD) have recently emerged. Hearts from DCD donors suffer significant ischemic injury prior to organ procurement; therefore, the traditional approach to the transplantation of hearts from brain-dead donors is not applicable to the DCD context. Advances in our understanding of ischemic post-conditioning have facilitated the development of DCD heart resuscitation strategies that can be used to minimize ischemia-reperfusion injury at the time of organ procurement. The availability of a clinically approved ex situ heart perfusion device now allows DCD heart preservation in a normothermic beating state and minimizes exposure to incremental cold ischemia. This technology also facilitates assessments of organ viability to be undertaken prior to transplantation, thereby minimizing the risk of primary graft dysfunction. The application of a tailored approach to DCD heart transplantation that focuses on organ resuscitation at the time of procurement, ex situ preservation, and pre-transplant assessments of organ viability has facilitated the successful clinical application of DCD heart transplantation. The transplantation of hearts from DCD donors is now a clinical reality. Investigating ways to optimize the resuscitation, preservation, evaluation, and long-term outcomes is vital to ensure a broader application of DCD heart transplantation in the future. PMID:29487855

  19. Heart Anatomy

    Science.gov (United States)

    ... kilometers), which is far enough to circle the earth more than twice! See also on other sites: ... For the Public Heart Information Center Project Heart Women’s Heart Health Clinical Trials 6770 Bertner Avenue Houston, ...

  20. Failure of intravenous or intracardiac delivery of mesenchymal stromal cells to improve outcomes after focal traumatic brain injury in the female rat.

    Directory of Open Access Journals (Sweden)

    L Christine Turtzo

    Full Text Available Mesenchymal stromal cells secrete a variety of anti-inflammatory factors and may provide a regenerative medicine option for the treatment of traumatic brain injury. The present study investigates the efficacy of multiple intravenous or intracardiac administrations of rat mesenchymal stromal cells or human mesenchymal stromal cells in female rats after controlled cortical impact by in vivo MRI, neurobehavior, and histopathology evaluation. Neither intravenous nor intracardiac administration of mesenchymal stromal cells derived from either rats or humans improved MRI measures of lesion volume or neurobehavioral outcome compared to saline treatment. Few mesenchymal stromal cells (<0.0005% of injected dose were found within 3 days of last dosage at the site of injury after either delivery route, with no mesenchymal stromal cells being detectable in brain at 30 or 56 days post-injury. These findings suggest that non-autologous mesenchymal stromal cells therapy via intravenous or intracardiac administration is not a promising treatment after focal contusion traumatic brain injury in this female rodent model.

  1. A Bone Metastasis Nude Mouse Model Created by Ultrasound Guided Intracardiac Injection of Breast Cancer Cells: the Micro-CT, MRI and Bioluminescence Imaging Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Park, Young Jin; Song, Eun Hye; Kim, Seol Hwa; Song, Ho Taek; Suh, Jin Suck [Yonsei University College of Medicine, Seoul (Korea, Republic of); Choi, Sang Hyun [Korean Minjok Leadership Academy, Heongsung (Korea, Republic of)

    2011-01-15

    The purpose of this study was to develop a nude mouse model of bone metastasis by performing intracardiac injection of breast cancer cells under ultrasonography guidance and we wanted to evaluate the development and the distribution of metastasis in vivo using micro-CT, MRI and bioluminescence imaging. Animal experiments were performed in 6-week-old female nude mice. The animals underwent left ventricular injection of 2x105 MDA-MB-231Bo-Luc cells. After injection of the tumor cells, serial bioluminescence imaging was performed for 7 weeks. The findings of micro-CT, MRI and the histology were correlated with the 'hot' lesions seen on the bioluminescence imaging. Metastasis was found in 62.3% of the animals. Two weeks after intracardiac injection, metastasis to the brain, spine and femur was detected with bioluminescence imaging with an increasing intensity by week 7. Micro-CT scan confirmed multiple osteolytic lesions at the femur, spine and skull. MRI and the histology were able to show metastasis in the brain and extraskeletal metastasis around the femur. The intracardiac injection of cancer cells under ultrasonography guidance is a safe and highly reproducible method to produce bone metastasis in nude mice. This bone metastasis nude mouse model will be useful to study the mechanism of bone metastasis and to validate new therapeutics

  2. The Design and Use of an Optical Mapping System for the Study of Intracardiac Electrical Signaling

    Directory of Open Access Journals (Sweden)

    Maneesh Shrivastav, PhD

    2012-07-01

    Full Text Available Fluorescent optical mapping of electrically active cardiac tissues provides a unique method to examine the excitation wave dynamics of underlying action potentials. Such mapping can be viewed as a bridge between cellular level and organ systems physiology, e.g., by facilitating the development of advanced theoretical concepts of arrhythmia. We present the design and use of a high-speed, high-resolution optical mapping system composed entirely of “off the shelf” components. The electrical design integrates a 256 element photodiode array with a 16 bit data acquisition system. Proper grounding and shielding at various stages of the design reduce electromagnetic interference. Our mechanical design provides flexibility in terms of mounting positions and applications (use for whole heart or tissue preparations, while maintaining precise alignment between all optical components. The system software incorporates a user friendly graphical user interface, e.g., spatially recorded action potentials can be represented as intensity graphs or in strip chart format. Thus, this system is capable of displaying cardiac action potentials with high spatiotemporal resolution. Results from cardiac action potential mapping with intact mouse hearts are provided. It should be noted that this system could be readily configured to study isolated myocardial biopsies (e.g., isolated ventricular trabeculae. We describe the details of a versatile, user-friendly system that could be employed for a magnitude of study protocols.

  3. Heart rate variability is severely impaired among type 2 diabetic patients with hypertension.

    Science.gov (United States)

    Istenes, Ildikó; Körei, Anna Erzsébet; Putz, Zsuzsanna; Németh, Nóra; Martos, Timea; Keresztes, Katalin; Kempler, Miklós Soma; Erzsébet, Vági Orsolya; Vargha, Péter; Kempler, Péter

    2014-05-01

    The aim of our study was to evaluate the relative effect of diabetes and hypertension on heart rate variability. Four age-matched groups including type 2 diabetic patients with and without hypertension, non-diabetic patients with essential hypertension and healthy control subjects were studied. Autonomic function was evaluated by the standard cardiovascular reflex tests and 24-hour heart rate variability measurement. Heart rate variability was characterized by the triangular index value and by the spectral components of the frequency domain analysis. According to the two-way analysis of variance on ranks, all parameters were influenced negatively by diabetes (heart rate variability triangular index: p heart rate variability parameters are additive. Beat-to-beat variation upon deep breathing, the most sensitive cardiovascular reflex test was also negatively influenced by both diabetes (p heart rate variability. Early assessment of the autonomic nerve function is suggested in diabetic patients with hypertension. Copyright © 2013 John Wiley & Sons, Ltd.

  4. Study on the Relationship among Parents' Cognition on China Anti-Domestic Violence, Attitude of Beating Children and Frequency of Beating Children

    Science.gov (United States)

    Song, Shi

    2018-01-01

    This research aims at analyzing the correlation between parents' awareness of anti-domestic violence in China, attitude and frequency of beating children. According to the literature analysis, this paper sets children's parents' anti-domestic violence cognition and attitude of beating children as independent variable, and the frequency of beating…

  5. Hemodynamics of Right Heart in Healthy Children according to Doppler Echocardiography

    Directory of Open Access Journals (Sweden)

    V.A. Kondratiev

    2015-10-01

    Full Text Available There was studied intracardiac hemodynamics in 96 healthy children aged from 3 to 15 years old. There were identified age-related standards for dopplerechocardiography parameters of right heart, which can be used for the diagnosis of pathological abnormalities of the cardiac functionality in children with cardiac and somatic pathology in the practice of pediatrics and pediatric cardiology. The use of standardized methodological approaches to the assessment of systolic and diastolic function of the right ventricle will allow compare the results of studies obtained in different clinics, and use these data in scientific research.

  6. Neural Entrainment and Sensorimotor Synchronization to the Beat in Children with Developmental Dyslexia: An EEG Study

    Directory of Open Access Journals (Sweden)

    Lincoln J. Colling

    2017-07-01

    Full Text Available Tapping in time to a metronome beat (hereafter beat synchronization shows considerable variability in child populations, and individual differences in beat synchronization are reliably related to reading development. Children with developmental dyslexia show impairments in beat synchronization. These impairments may reflect deficiencies in auditory perception of the beat which in turn affect auditory-motor mapping, or may reflect an independent motor deficit. Here, we used a new methodology in EEG based on measuring beat-related steady-state evoked potentials (SS-EPs, Nozaradan et al., 2015 in an attempt to disentangle neural sensory and motor contributions to behavioral beat synchronization in children with dyslexia. Children tapped with both their left and right hands to every second beat of a metronome pulse delivered at 2.4 Hz, or listened passively to the beat. Analyses of preferred phase in EEG showed that the children with dyslexia had a significantly different preferred phase compared to control children in all conditions. Regarding SS-EPs, the groups differed significantly for the passive Auditory listening condition at 2.4 Hz, and showed a trend toward a difference in the Right hand tapping condition at 3.6 Hz (sensorimotor integration measure. The data suggest that neural rhythmic entrainment is atypical in children with dyslexia for both an auditory beat and during sensorimotor coupling (tapping. The data are relevant to a growing literature suggesting that rhythm-based interventions may help language processing in children with developmental disorders of language learning.

  7. Prostanoid Receptors Involved in Regulation of the Beating Rate of Neonatal Rat Cardiomyocytes

    Science.gov (United States)

    Mechiche, Hakima; Grassin-Delyle, Stanislas; Robinet, Arnaud; Nazeyrollas, Pierre; Devillier, Philippe

    2012-01-01

    Although prostanoids are known to be involved in regulation of the spontaneous beating rate of cultured neonatal rat cardiomyocytes, the various subtypes of prostanoid receptors have not been investigated in detail. In our experiments, prostaglandin (PG)F2α and prostanoid FP receptor agonists (fluprostenol, latanoprost and cloprostenol) produced a decrease in the beating rate. Two prostanoid IP receptor agonists (iloprost and beraprost) induced first a marked drop in the beating rate and then definitive abrogation of beating. In contrast, the prostanoid DP receptor agonists (PGD2 and BW245C) and TP receptor agonists (U-46619) produced increases in the beating rate. Sulprostone (a prostanoid EP1 and EP3 receptor agonist) induced marked increases in the beating rate, which were suppressed by SC-19220 (a selective prostanoid EP1 antagonist). Butaprost (a selective prostanoid EP2 receptor agonist), misoprostol (a prostanoid EP2 and EP3 receptor agonist), 11-deoxy-PGE1 (a prostanoid EP2, EP3 and EP4 receptor agonist) did not alter the beating rate. Our results strongly suggest that prostanoid EP1 receptors are involved in positive regulation of the beating rate. Prostanoid EP1 receptor expression was confirmed by western blotting with a selective antibody. Hence, neonatal rat cardiomyocytes express both prostanoid IP and FP receptors (which negatively regulate the spontaneous beating rate) and prostanoid TP, DP1 and EP1 receptors (which positively regulate the spontaneous beating rate). PMID:22984630

  8. Congenital Heart Disease: Causes, Diagnosis, Symptoms, and Treatments.

    Science.gov (United States)

    Sun, RongRong; Liu, Min; Lu, Lei; Zheng, Yi; Zhang, Peiying

    2015-07-01

    The congenital heart disease includes abnormalities in heart structure that occur before birth. Such defects occur in the fetus while it is developing in the uterus during pregnancy. About 500,000 adults have congenital heart disease in USA (WebMD, Congenital heart defects medications, www.WebMD.com/heart-disease/tc/congenital-heart-defects-medications , 2014). 1 in every 100 children has defects in their heart due to genetic or chromosomal abnormalities, such as Down syndrome. The excessive alcohol consumption during pregnancy and use of medications, maternal viral infection, such as Rubella virus, measles (German), in the first trimester of pregnancy, all these are risk factors for congenital heart disease in children, and the risk increases if parent or sibling has a congenital heart defect. These are heart valves defects, atrial and ventricular septa defects, stenosis, the heart muscle abnormalities, and a hole inside wall of the heart which causes defect in blood circulation, heart failure, and eventual death. There are no particular symptoms of congenital heart disease, but shortness of breath and limited ability to do exercise, fatigue, abnormal sound of heart as heart murmur, which is diagnosed by a physician while listening to the heart beats. The echocardiogram or transesophageal echocardiogram, electrocardiogram, chest X-ray, cardiac catheterization, and MRI methods are used to detect congenital heart disease. Several medications are given depending on the severity of this disease, and catheter method and surgery are required for serious cases to repair heart valves or heart transplantation as in endocarditis. For genetic study, first DNA is extracted from blood followed by DNA sequence analysis and any defect in nucleotide sequence of DNA is determined. For congenital heart disease, genes in chromosome 1 show some defects in nucleotide sequence. In this review the causes, diagnosis, symptoms, and treatments of congenital heart disease are described.

  9. Unusual abdominal tumors with intracardiac extension. Two cases with successful surgical resection

    Directory of Open Access Journals (Sweden)

    Stolf Noedir A. G.

    1999-01-01

    Full Text Available Abdominal tumors that can grow through vascular lumen and spread to the right heart are rare. Although these tumors have different histologic aspects, they may cause similar abdominal and cardiac symptoms and are a serious risk factor for pulmonary embolism and sudden death when they reach the right atrium and tricuspid valve. The best treatment is radical surgical resection of the entire tumor using cardiopulmonary bypass with or without deep hypothermia and total circulatory arrest. We report the cases of two patients, the first with leiomyosarcoma of the inferior vena cava and the other with intravenous leiomyomatosis of the uterus that showed intravascular growth up to right atrium and ventricle, who underwent successful radical resection in a one-stage procedure with the use of cardiopulmonary bypass. We discuss the clinical and histologic aspects and imaging diagnosis and review the literature.

  10. Automated tissue classification of intracardiac optical coherence tomography images (Conference Presentation)

    Science.gov (United States)

    Gan, Yu; Tsay, David; Amir, Syed B.; Marboe, Charles C.; Hendon, Christine P.

    2016-03-01

    Remodeling of the myocardium is associated with increased risk of arrhythmia and heart failure. Our objective is to automatically identify regions of fibrotic myocardium, dense collagen, and adipose tissue, which can serve as a way to guide radiofrequency ablation therapy or endomyocardial biopsies. Using computer vision and machine learning, we present an automated algorithm to classify tissue compositions from cardiac optical coherence tomography (OCT) images. Three dimensional OCT volumes were obtained from 15 human hearts ex vivo within 48 hours of donor death (source, NDRI). We first segmented B-scans using a graph searching method. We estimated the boundary of each region by minimizing a cost function, which consisted of intensity, gradient, and contour smoothness. Then, features, including texture analysis, optical properties, and statistics of high moments, were extracted. We used a statistical model, relevance vector machine, and trained this model with abovementioned features to classify tissue compositions. To validate our method, we applied our algorithm to 77 volumes. The datasets for validation were manually segmented and classified by two investigators who were blind to our algorithm results and identified the tissues based on trichrome histology and pathology. The difference between automated and manual segmentation was 51.78 +/- 50.96 μm. Experiments showed that the attenuation coefficients of dense collagen were significantly different from other tissue types (P < 0.05, ANOVA). Importantly, myocardial fibrosis tissues were different from normal myocardium in entropy and kurtosis. The tissue types were classified with an accuracy of 84%. The results show good agreements with histology.

  11. 3-D ultrasound imaging using a forward-looking CMUT ring array for intravascular/intracardiac applications.

    Science.gov (United States)

    Yeh, David T; Oralkan, Omer; Wygant, Ira O; O'Donnell, Matthew; Khuri-Yakub, Butrus T

    2006-06-01

    Forward-viewing ring arrays can enable new applications in intravascular and intracardiac ultrasound. This work presents compelling, full-synthetic, phased-array volumetric images from a forward-viewing capacitive micromachined ultrasonic transducer (CMUT) ring array wire bonded to a custom integrated circuit front end. The CMUT ring array has a diameter of 2 mm and 64 elements each 100 microm x 100 microm in size. In conventional mode, echo signals received from a plane reflector at 5 mm had 70% fractional bandwidth around a center frequency of 8.3 MHz. In collapse mode, 69% fractional bandwidth is measured around 19 MHz. Measured signal-to-noise ratio (SNR) of the echo averaged 16 times was 29 dB for conventional operation and 35 dB for collapse mode. B-scans were generated of a target consisting of steel wires 0.3 mm in diameter to determine resolution performance. The 6 dB axial and lateral resolutions for the B-scan of the wire target are 189 microm and 0.112 radians for 8 MHz, and 78 microm and 0.051 radians for 19 MHz. A reduced firing set suitable for real-time, intravascular applications was generated and shown to produce acceptable images. Rendered three-dimensional (3-D) images of a Palmaz-Schatz stent also are shown, demonstrating that the imaging quality is sufficient for practical applications.

  12. [Behçet's disease: Intracardiac thrombosis (a description of two cases and a review of literature)].

    Science.gov (United States)

    Alekberova, Z S; Ovcharov, P S; Lisitsyna, T A; Volkov, A V; Popkova, T V

    Behçet's disease (BD) is systemic vasculitis of unknown etiology, which is more common in the countries located along the Great Silk Road. The disease is diagnosed if a patient has 4 key diagnostic signs: aphthous stomatitis, genital sores, and eye and skin lesions. Vascular diseases referred to as minor criteria for BD are characterized by the formation of aneurysms and thrombosis, predominantly in the venous bed. In venous disorders, a blood clot can form in any vessel, including caval, cerebral, pulmonary, and other veins. The paper describes two clinical cases of BD with intracardiac thrombosis. In one case, a 24-year-old male patient with a documented diagnosis of BD, echocardiography revealed a left ventricular spontaneous echo contrast phenomenon that disappeared due to immunosuppressive therapy. The other case was a 34-year-old female patient, in whom the diagnosis was based on the international disease criteria: aphthous stomatitis, skin lesions (pseudopustulosis, erythema nodosum), and genital sores. Computed tomographic angiography showed a 3.7×2.2-cm mass (thrombus) in the right atrium. In addition, blood clots were present in the hepatic and inferior vena cava. No abnormalities in the coagulation system were found in both cases.

  13. Evaluation of aspirin therapy on intracardiac thrombi using indium-111-oxine platelet scintigraphy, two-dimentional echocardiography and left ventriculography

    International Nuclear Information System (INIS)

    Shibuya, Masanori; Irino, Tadayoshi; Yoshioka, Toshiharu; Sugimoto, Tsuyoshi; Tsuji, Kazuo; Naka, Masashi; Arai, Hidekazu.

    1984-01-01

    Left ventriculography (LVG), two-dimensional echocardiography (2-DE) and indium-111-oxine platelet scintigraphy were performed in five patients with intracardiac thrombi. Thrombi were visible in 7 sites (5 in the ventricle and 2 in the atrium) by platelet scintigraphy, in 4 sites (3 in the ventricle and 1 in the atrium) by 2-DE, and in 4 sites (4 in the ventricle) by LVG. When aspirin was administered to the patients, platelet scintigraphy had become negative for thrombi in 5 sites and false-negative for them in 2 sites. However, thrombi were detected in 6 sites after the withdrawal of aspirin. On the other hand, thrombi were detected in 4 sites by 2-DE, irrespective of the administration of aspirin. Indium-111-oxine platelet scintigraphy has proved to not only have higher sensitivity for detecting thrombi but also to be capable of observing the coagulation status of platelets on the thrombi. It is therefore considered very helpful in assessing anticoagulation therapy. (Namekawa, K)

  14. Effect of Temperature on Heart Rate Variability in Neonatal ICU Patients With Hypoxic-Ischemic Encephalopathy.

    Science.gov (United States)

    Massaro, An N; Campbell, Heather E; Metzler, Marina; Al-Shargabi, Tareq; Wang, Yunfei; du Plessis, Adre; Govindan, Rathinaswamy B

    2017-04-01

    To determine whether measures of heart rate variability are related to changes in temperature during rewarming after therapeutic hypothermia for hypoxic-ischemic encephalopathy. Prospective observational study. Level 4 neonatal ICU in a free-standing academic children's hospital. Forty-four infants with moderate to severe hypoxic-ischemic encephalopathy treated with therapeutic hypothermia. Continuous electrocardiogram data from 2 hours prior to rewarming through 2 hours after completion of rewarming (up to 10 hr) were analyzed. Median beat-to-beat interval and measures of heart rate variability were quantified including beat-to-beat interval SD, low and high frequency relative spectral power, detrended fluctuation analysis short and long α exponents (αS and αL), and root mean square short and long time scales. The relationships between heart rate variability measures and esophageal/axillary temperatures were evaluated. Heart rate variability measures low frequency, αS, and root mean square short and long time scales were negatively associated, whereas αL was positively associated, with temperature (p variability as temperature increased toward normothermia. Measures of heart rate variability are temperature dependent in the range of therapeutic hypothermia to normothermia. Core body temperature needs to be considered when evaluating heart rate variability metrics as potential physiologic biomarkers of illness severity in hypoxic-ischemic encephalopathy infants undergoing therapeutic hypothermia.

  15. Multidetector CT for congenital heart patients: what a paediatric radiologist should know

    Energy Technology Data Exchange (ETDEWEB)

    Paul, Jean-Francois; Rohnean, Adela; Sigal-Cinqualbre, Anne [Radiology Unit, Marie Lannelongue Hospital, Plessis-Robinson (France)

    2010-06-15

    Multidetector CT (MDCT) is increasingly used for imaging congenital heart disease (CHD) patients in addition to echocardiography, due to its ability to provide high quality three-dimensional images, giving a comprehensive evaluation of complex heart malformations. Using 4-slice or 16-slice CT, diagnostic information in CHD patients is limited to extra-cardiac anatomy, mainly the pulmonary arteries, aorta and venous connections. Due to high heart rates in babies however, coronary evaluation and intra-cardiac analysis were not reliable with the first generations of MDCT. Larger detector size with 64-slice CT and faster acquisition time, up to 75 ms for one slice, has progressively improved coronary and intra-cardiac visualization. Because radiation dose is the main concern, especially in children, every attempt to minimize dose whilst preserving image quality is important: the ALARA concept should always be applied in this population. The 80 kVp setting is now well accepted as a standard for more and more radiological teams involved in CT of children. Different acquisition strategies are now possible for childhood coronary imaging, using retrospective or even prospective gating. Using the latest technology, sub-mSv acquisitions are now attainable for scanning a whole thorax, providing a complete analysis of any 3-D cardiac malformation, including coronary artery course visualisation. This review will describe how technological developments have improved image quality with continuous reduction of radiation dose. (orig.)

  16. Heart Attack

    Science.gov (United States)

    Each year almost 800,000 Americans have a heart attack. A heart attack happens when blood flow to the heart suddenly ... it's important to know the symptoms of a heart attack and call 9-1-1 if you or ...

  17. Heart Transplantation

    Science.gov (United States)

    A heart transplant removes a damaged or diseased heart and replaces it with a healthy one. The healthy heart comes from a donor who has died. It is the last resort for people with heart failure when all other treatments have failed. The ...

  18. Heart Diseases

    Science.gov (United States)

    ... re like most people, you think that heart disease is a problem for others. But heart disease is the number one killer in the U.S. ... disability. There are many different forms of heart disease. The most common cause of heart disease is ...

  19. Wavelet-based segmentation and feature extraction of heart sounds for intelligent PDA-based phonocardiography.

    Science.gov (United States)

    Nazeran, H

    2007-01-01

    Many pathological conditions of the cardiovascular system cause murmurs and aberrations in heart sounds. Phonocardiography provides the clinician with a complementary tool to record the heart sounds heard during auscultation. The advancement of intracardiac phonocardiography combined with modern digital signal processing techniques has strongly renewed researchers' interest in studying heart sounds and murmurs. The aim of this work is to investigate the applicability of different spectral analysis methods to heart sound signals and explore their suitability for PDA-based implementation. Fourier transform (FT), short-time Fourier transform (STFT) and wavelet transform (WT) are used to perform spectral analysis on heart sounds. A segmentation algorithm based on Shannon energy is used to differentiate between first and second heart sounds. Then wavelet transform is deployed again to extract 64 features of heart sounds. The FT provides valuable frequency information but the timing information is lost during the transformation process. The STFT or spectrogram provides valuable time-frequency information but there is a trade-off between time and frequency resolution. Wavelet analysis, however, does not suffer from limitations of the STFT and provides adequate time and frequency resolution to accurately characterize the normal and pathological heart sounds. The results show that the wavelet-based segmentation algorithm is quite effective in localizing the important components of both normal and abnormal heart sounds. They also demonstrate that wavelet-based feature extraction provides suitable feature vectors which are clearly differentiable and useful for automatic classification of heart sounds.

  20. Effect of heart rate on the hemodynamics of bileaflet mechanical heart valves' prostheses (St. Jude Medical) in the aortic position and in the opening phase: A computational study.

    Science.gov (United States)

    Jahandardoost, Mehdi; Fradet, Guy; Mohammadi, Hadi

    2016-03-01

    To date, to the best of the authors' knowledge, in almost all of the studies performed around the hemodynamics of bileaflet mechanical heart valves, a heart rate of 70-72 beats/min has been considered. In fact, the heart rate of ~72 beats/min does not represent the entire normal physiological conditions under which the aortic or prosthetic valves function. The heart rates of 120 or 50 beats/min may lead to hemodynamic complications, such as plaque formation and/or thromboembolism in patients. In this study, the hemodynamic performance of the bileaflet mechanical heart valves in a wide range of normal and physiological heart rates, that is, 60-150 beats/min, was studied in the opening phase. The model considered in this study was a St. Jude Medical bileaflet mechanical heart valve with the inner diameter of 27 mm in the aortic position. The hemodynamics of the native valve and the St. Jude Medical valve were studied in a variety of heart rates in the opening phase and the results were carefully compared. The results indicate that peak values of the velocity profile downstream of the valve increase as heart rate increases, as well as the location of the maximum velocity changes with heart rate in the St. Jude Medical valve model. Also, the maximum values of shear stress and wall shear stresses downstream of the valve are proportional to heart rate in both models. Interestingly, the maximum shear stress and wall shear stress values in both models are in the same range when heart rate is valve model when heart rate is >90 beats/min (up to ~40% growth compared to that of the native valve). The findings of this study may be of importance in the hemodynamic performance of bileaflet mechanical heart valves. They may also play an important role in design improvement of conventional prosthetic heart valves and the design of the next generation of prosthetic valves, such as percutaneous valves. © IMechE 2016.

  1. Wife beating amongst Africans as a challenge to pastoral care

    Directory of Open Access Journals (Sweden)

    Magezi E. Baloyi

    2013-11-01

    Full Text Available Traditional African people are known for respecting their marriage. Even though marriage is so highly regarded, it is astonishing to realise that wife beating has become an extremely common practice amongst them. It therefore becomes an important research question to ask about the extent to which deeply-seated traditional customs regarding wife beating as a form of stamping down authority and of trying to keep the household in order, will have to be confronted with what is deemed to be good practice from the perspective of the law, community and pastoral caregivers. There are women who live with scars on their faces and bodies, having been beaten by their husbands. Although there are many forms of abuse towards women in family situations, this article aims particularly to focus on wife beating that is practiced for traditional as well as other related reasons. This research will involve itself with establishing whether the reasons for wife beating are part of the traditional system for keeping the household in order and interrogate both legal and pastoral interventions that attempt to eliminate or avoid such behaviour. Tradisionele Afrikane is nog altyd daarvoor bekend dat hulle die instelling van die huwelik respekteer. Verbasend genoeg is vroueslanery egter ’n ou gevestigde gebruik wat vandag algemeen onder Afrikane voorkom. Die mate waartoe diepgewortelde gebruike soos vroueslanery as ’n manier om gesag af te dwing en orde in die huis te handhaaf, gekonfronteer sal moet word met wat as goeie praktyk beskou word vanuit die gesigspunt van die reg, die gemeenskap en pastorale versorgers, is dus ’n belangrike navorsingsvraag. Baie vroue dra fisiese en emosionele littekens wat deur hulle eggenote veroorsaak is. Alhoewel daar baie vorme van vrouemishandeling in familiesituasies voorkom, fokus hierdie artikel veral op vroueslanery wat om tradisionele en verwante redes beoefen word. Hierdie navorsing probeer vasstel of die redes vir

  2. MHD simulation of a beat frequency heated plasma

    International Nuclear Information System (INIS)

    Milroy, R.D.; Capjack, C.E.; James, C.R.; McMullin, J.N.

    1976-01-01

    The heating of a plasma in a solenoid, with a beat frequency harmonic which is excited at a frequency near to that of a Langmuir mode in a plasma, is examined. It is shown that at high temperatures the heating rate is very insensitive to changes in plasma density. The amount of energy that can be coupled to a plasma in a solenoid with this heating scheme is investigated by using a one-dimensional computer code which incorporates an exact solution of the relevant MHD equations. The absorption of energy from a high powered laser is shown to be significantly enhanced with this process. (author)

  3. Run to the Beat: Sport and music for the masses

    OpenAIRE

    Karageorghis, CI

    2013-01-01

    Run to the Beat is a half marathon event that is accompanied by live and pre-recorded music. The author was involved with the event as the lead consultant in the period 2007-2010. This case study examines the genesis of the event, the science on which it was predicated and how it was received by participating runners and the media. The primary driver for the event was the 2007 ban on personal listening devices by the International Amateur Athletics Federation, which outraged recreational runn...

  4. Gaussian-state entanglement in a quantum beat laser

    International Nuclear Information System (INIS)

    Tahira, Rabia; Ikram, Manzoor; Nha, Hyunchul; Zubairy, M. Suhail

    2011-01-01

    Recently quantum beat lasers have been considered as a source of entangled radiation [S. Qamar, F. Ghafoor, M. Hillery, and M. S. Zubairy, Phys. Rev. A 77, 062308 (2008)]. We investigate and quantify the entanglement of this system when the initial cavity modes are prepared in a Gaussian two-mode state, one being a nonclassical state and the other a thermal state. It is investigated how the output entanglement varies with the nonclassicality of the input Gaussian state, thermal noise, and the strength of the driving field.

  5. Individual differences in beat perception affect gait responses to low- and high-groove music.

    Directory of Open Access Journals (Sweden)

    Li-Ann eLeow

    2014-10-01

    Full Text Available Slowed gait in Parkinson’s disease (PD patients can be improved when patients synchronize footsteps to isochronous metronome cues, but limited retention of such improvements suggest that permanent cueing regimes are needed for long-term improvements. If so, music might make permanent cueing regimes more pleasant, improving adherence; however, music cueing requires patients to synchronize movements to the beat, which might be difficult for PD patients who tend to show weak beat perception. One solution may be to use high groove music, which has high beat salience that may facilitate synchronization, and affective properties which may improve motivation to move. As a first step in understanding how beat perception affects gait in complex neurological disorders, we examined how beat perception ability affected gait in neurotypical adults. Synchronization performance and gait parameters were assessed as healthy young adults with strong or weak beat perception synchronized to low groove music, high groove music, and metronome cues. High groove music was predicted to elicit better synchronization than low groove music, due to its higher beat salience. Two musical tempi, or rates, were used: (1 preferred tempo: beat rate matched to preferred step rate and (2 faster tempo: beat rate adjusted to 22.5% faster than preferred step rate. For both strong and weak beat-perceivers, synchronization performance was best with metronome cues, followed by high groove music, and worst with low groove music. In addition, high groove music elicited longer and faster steps than low groove music, both at preferred tempo and at faster tempo. Low groove music was particularly detrimental to gait in weak beat-perceivers, who showed slower and shorter steps compared to uncued walking. The findings show that individual differences in beat perception affect gait when synchronizing footsteps to music, and have implications for using music in gait rehabilitation.

  6. The effect of binaural beats on verbal working memory and cortical connectivity

    OpenAIRE

    Beauchene, Christine; Abaid, Nicole; Moran, Rosalyn; Diana, Rachel A.; Leonessa, Alexander

    2017-01-01

    Objective. Synchronization in activated regions of cortical networks affect the brain's frequency response, which has been associated with a wide range of states and abilities, including memory. A non-invasive method for manipulating cortical synchronization is binaural beats. Binaural beats take advantage of the brain's response to two pure tones, delivered independently to each ear, when those tones have a small frequency mismatch. The mismatch between the tones is interpreted as a beat fre...

  7. The Effect of Binaural Beats on Visuospatial Working Memory and Cortical Connectivity

    OpenAIRE

    Beauchene, C.; Abaid, N; Moran, Rosalyn; Diana, R; Leonessa, A

    2016-01-01

    Binaural beats utilize a phenomenon that occurs within the cortex when two different frequencies are presented separately to each ear. This procedure produces a third phantom binaural beat, whose frequency is equal to the difference of the two presented tones and which can be manipulated for non-invasive brain stimulation. The effects of binaural beats on working memory, the system in control of temporary retention and online organization of thoughts for successful goal directed behavior, hav...

  8. Response of cat inferior colliculus neurons to binaural beat stimuli: possible mechanisms for sound localization.

    Science.gov (United States)

    Kuwada, S; Yin, T C; Wickesberg, R E

    1979-11-02

    The interaural phase sensitivity of neurons was studied through the use of binaural beat stimuli. The response of most cells was phase-locked to the beat frequency, which provides a possible neural correlate to the human sensation of binaural beats. In addition, this stimulus allowed the direction and rate of interaural phase change to be varied. Some neurons in our sample responded selectively to manipulations of these two variables, which suggests a sensitivity to direction or speed of movement.

  9. Results of Cryoenergy and Radiofrequency-Based Catheter Ablation for Treating Ventricular Arrhythmias Arising From the Papillary Muscles of the Left Ventricle, Guided by Intracardiac Echocardiography and Image Integration.

    Science.gov (United States)

    Rivera, Santiago; Ricapito, Maria de la Paz; Tomas, Leandro; Parodi, Josefina; Bardera Molina, Guillermo; Banega, Rodrigo; Bueti, Pablo; Orosco, Agustin; Reinoso, Marcelo; Caro, Milagros; Belardi, Diego; Albina, Gaston; Giniger, Alberto; Scazzuso, Fernando

    2016-04-01

    Catheter radiofrequency ablation of ventricular arrhythmias (VAs) arising from the left ventricle's papillary muscles has been associated with inconsistent results. The use of cryoenergy versus radiofrequency has not been compared yet. This study compares outcomes and complications of catheter ablation of VA from the papillary muscles of the left ventricle with either cryoenergy or radiofrequency. Twenty-one patients (40±12 years old; 47% males; median ejection fraction 59±7.3%) with drug refractory premature ventricular contractions or ventricular tachycardia underwent catheter cryoablation or radiofrequency ablation. VAs were localized using 3-dimensional mapping, multidetector computed tomography, and intracardiac echocardiography, with arrhythmia foci being mapped at either the anterolateral papillary muscle or posteromedial papillary muscles of the left ventricle. Focal ablation was performed using an 8-mm cryoablation catheter or a 4-mm open-irrigated radiofrequency catheter, via transmitral approach. Acute success rate was 100% for cryoenergy (n=12) and 78% for radiofrequency (n=9; P=0.08). Catheter stability was achieved in all patients (100%) treated with cryoenergy, and only in 2 (25%) patients treated with radiofrequency (P=0.001). Incidence of multiple VA morphologies was observed in 7 patients treated with radiofrequency (77.7%), whereas none was observed in those treated with cryoenergy (P=0.001). VA recurrence at 6 months follow-up was 0% for cryoablation and 44% for radiofrequency (P=0.03). Cryoablation was associated with higher success rates and lower recurrence rates than radiofrequency catheter ablation, better catheter stability, and lesser incidence of polymorphic arrhythmias. © 2016 American Heart Association, Inc.

  10. Enhanced Timing Abilities in Percussionists Generalize to Rhythms Without a Musical Beat

    Directory of Open Access Journals (Sweden)

    Daniel J Cameron

    2014-12-01

    Full Text Available The ability to entrain movements to music is arguably universal, but it is unclear how specialized training may influence this. Previous research suggests that percussionists have superior temporal precision in perception and production tasks. Such superiority may be limited to temporal sequences that resemble real music or, alternatively, may generalize to musically implausible sequences. To test this, percussionists and nonpercussionists completed two tasks that used rhythmic sequences varying in musical plausibility. In the beat tapping task, participants tapped with the beat of a rhythmic sequence over 3 stages: finding the beat (as an initial sequence played, continuation of the beat (as a second sequence was introduced and played simultaneously, and switching to a second beat (the initial sequence finished, leaving only the second. The metres of the two sequences were either congruent or incongruent, as were their tempi (minimum inter-onset intervals. In the rhythm reproduction task, participants reproduced rhythms of four types, ranging from high to low musical plausibility: Metric simple rhythms induced a strong sense of the beat, metric complex rhythms induced a weaker sense of the beat, nonmetric rhythms had no beat, and jittered nonmetric rhythms also had no beat as well as low temporal predictability. For both tasks, percussionists performed more accurately than nonpercussionists. In addition, both groups were better with musically plausible than implausible conditions. Overall, the percussionists’ superior abilities to entrain to, and reproduce, rhythms generalized to musically implausible sequences.

  11. Reduced intrinsic heart rate is associated with reduced arrhythmic susceptibility in guinea-pig heart.

    Science.gov (United States)

    Osadchii, Oleg E

    2014-12-01

    In the clinical setting, patients with slower resting heart rate are less prone to cardiovascular death compared with those with elevated heart rate. However, electrophysiological adaptations associated with reduced cardiac rhythm have not been thoroughly explored. In this study, relationships between intrinsic heart rate and arrhythmic susceptibility were examined by assessments of action potential duration (APD) rate adaptation and inducibility of repolarization alternans in sinoatrial node (SAN)-driven and atrioventricular (AV)-blocked guinea-pig hearts perfused with Langendorff apparatus. Electrocardiograms, epicardial monophasic action potentials, and effective refractory periods (ERP) were assessed in normokalemic and hypokalemic conditions. Slower basal heart rate in AV-blocked hearts was associated with prolonged ventricular repolarization during spontaneous beating, and with attenuated APD shortening at increased cardiac activation rates during dynamic pacing, when compared with SAN-driven hearts. During hypokalemic perfusion, the inducibility of repolarization alternans and tachyarrhythmia by rapid pacing was found to be lower in AV-blocked hearts. This difference was ascribed to prolonged ERP in the setting of reduced basal heart rate, which prevented ventricular capture at critically short pacing intervals required to induce arrhythmia. Reduced basal heart rate is associated with electrophysiological changes that prevent electrical instability upon an abrupt cardiac acceleration.

  12. Mathematical Modeling of Flow Characteristics in the Embryonic Chick Heart

    DEFF Research Database (Denmark)

    Heebøll-Christensen, Jesper

    modified inertia, and resistance due to friction and curvature of the multilayered tubular heart. Through the modeling, flow conditions in the embryonic heart are characterized. The models suggest that eccentric rather than concentric deformation of the beating heart is optimal for mean flows induced...... the models are not conclusive on this point. In addition the Liebau effect is investigated in a simpler system containing two elastic tubes joined to form a liquid filled ring, with a compression pump at an asymmetric location. Through comparison to other reports the system validates model construction...

  13. Understanding scuba diving fatalities: carbon dioxide concentrations in intra-cardiac gas.

    Science.gov (United States)

    Varlet, Vincent; Dominguez, Alejandro; Augsburger, Marc; Lossois, Maisy; Egger, Coraline; Palmiere, Cristian; Vilarino, Raquel; Grabherr, Silke

    2017-06-01

    Important developments in the diagnosis of scuba diving fatalities have been made thanks to forensic imaging tool improvements. Multi-detector computed tomography (MDCT) permits reliable interpretation of the overall gaseous distribution in the cadaver. However, due to post-mortem delay, the radiological interpretation is often doubtful because the distinction between gas related to the dive and post-mortem decomposition artifactual gases becomes less obvious. We present six cases of fatal scuba diving showing gas in the heart and other vasculature. Carbon dioxide (CO₂) in cardiac gas measured by gas chromatography coupled to thermal conductivity detection were employed to distinguish decomposition from embolism based on the detection of decomposition gases (hydrogen, hydrogen sulfide and methane) and to confirm arterial gas embolism (AGE) or post-mortem offgasing diagnoses. A Radiological Alteration Index (RAI) was calculated from the scan. Based on the dive history, the intra-cadaveric gas was diagnosed as deriving from decomposition (one case, minimal RAI of 61), post-mortem decompression artifacts (two cases, intermediate RAI between 60 and 85) and barotrauma/AGE (three cases, maximal RAI between 85 and 100), illustrating a large distribution inside the bodies. MDCT scans should be interpreted simultaneously with compositional analysis of intra-cadaveric gases. Intra-cadaveric gas sampling and analysis may become useful tools for understanding and diagnosing scuba diving fatalities. In cases with short post-mortem delays, the CO₂ concentration of the cardiac gas provides relevant information about the circumstances and cause of death when this parameter is interpreted in combination with the diving profile.

  14. smRithm: Graphical user interface for heart rate variability analysis.

    Science.gov (United States)

    Nara, Sanjeev; Kaur, Manvinder; Datta, Saurav

    2015-01-01

    Over the past 25 years, Heart rate variability (HRV) has become a non-invasive research and clinical tool for indirectly carrying out investigation of both cardiac and autonomic system function in both healthy and diseased. It provides valuable information about a wide range of cardiovascular disorders, pulmonary diseases, neurological diseases, etc. Its primary purpose is to access the functioning of the nervous system. The source of information for HRV analysis is the continuous beat to beat measurement of inter-beat intervals. The electrocardiography (ECG or EKG) is considered as the best way to measure inter-beat intervals. This paper proposes an open source Graphical User Interface (GUI): smRithm developed in MATLAB for HRV analysis that will apply effective techniques on the raw ECG signals to process and decompose it in a simpler manner to obtain more useful information out of signals that can be utilized for more powerful and efficient applications in the near future related to HRV.

  15. Beating the diffraction limit in astronomy via quantum cloning

    Science.gov (United States)

    Kellerer, A.

    2014-01-01

    Context. The diffraction limit is considered as the absolute boundary for the angular resolution of a telescope. Non-linear optical processes, however, allow the diffraction limit to be beaten non-deterministically. Aims: We examine the possibility of overcoming the diffraction limit of a telescope through photon cloning processes, heralded by trigger events. Whilst perfect cloning is ruled out by quantum mechanics, imperfect cloning is attainable and can beat the diffraction limit on a reduced fraction of photons. Methods: We suggest to insert a layer of excited atoms in a pupil plane of the telescope. When a photon from the astronomical source passes the pupil, it stimulates the emission of identical photons by the excited atoms. The set of photons arrives on a coincidence detector, and the average position of simultaneously arriving photons is recorded. The contribution of spontaneous emissions is minimized by use of a trigger signal, implemented via a quantum-non-demolition measurement. Results: The proposed set-up - an optical amplifier triggered by a quantum-non-demolition measurement - allows to beat the diffraction limit of a telescope, at the price of a loss in efficiency. The efficiency may, however, be compensated for through increased exposure times. Conclusions: The main conclusion is the possibility in principle to improve the angular resolution of a telescope beyond the diffraction limit and thus to achieve high-angular resolutions with moderately sized telescopes.

  16. Effect of Cilia Beat Frequency on Mucociliary Clearance

    Directory of Open Access Journals (Sweden)

    Sedaghat M. H.

    2016-12-01

    Full Text Available Background: The airway surface liquid (ASL, which is a fluid layer coating the interior epithelial surface of the bronchi and bronchiolesis, plays an important defensive role against foreign particles and chemicals entering lungs. Objective: Numerical investigation has been employed to solve two-layer model consisting of mucus layer as a viscoelastic fluid and periciliary liquid layer as a Newtonian fluid to study the effects of cilia beat frequency (CBF at various amounts of mucus properties on muco-ciliary transport problem. Methods: Hybrid finite difference-lattice Boltzmann-method (FB-LBM has been used to solve the momentum equations and to simulate cilia forces, and also the PCLmucus interface more accurately, immersed boundary method (IBM has been employed. The main contribution of the current study is to use an Oldroyd-B model as the constitutive equation of mucus. Results: Our results show that increasing CBF and decreasing mucus viscosity ratio have great effects on mucus flow, but the effect of viscosity ratio is more significant. The results also illustrate that the relation between cilia beat frequency and mean mucus velocity is almost linear and it has similar behavior at different values of viscosity ratio. Conclusion: Numerical investigation based on hybrid IB-FD-LBM has been used to study the effect of CBF at various mounts of mucus viscosity ratio on the muco-ciliary clearance. The results showed that the effect of viscosity ratio on the muco-ciliary transport process is more significant compared with CBF.

  17. Visibility graph analysis of heart rate time series and bio-marker of congestive heart failure

    Science.gov (United States)

    Bhaduri, Anirban; Bhaduri, Susmita; Ghosh, Dipak

    2017-09-01

    Study of RR interval time series for Congestive Heart Failure had been an area of study with different methods including non-linear methods. In this article the cardiac dynamics of heart beat are explored in the light of complex network analysis, viz. visibility graph method. Heart beat (RR Interval) time series data taken from Physionet database [46, 47] belonging to two groups of subjects, diseased (congestive heart failure) (29 in number) and normal (54 in number) are analyzed with the technique. The overall results show that a quantitative parameter can significantly differentiate between the diseased subjects and the normal subjects as well as different stages of the disease. Further, the data when split into periods of around 1 hour each and analyzed separately, also shows the same consistent differences. This quantitative parameter obtained using the visibility graph analysis thereby can be used as a potential bio-marker as well as a subsequent alarm generation mechanism for predicting the onset of Congestive Heart Failure.

  18. Fetal auditory responses to external sounds and mother's heart beat: detection improved by Independent Component Analysis.

    Science.gov (United States)

    Porcaro, Camillo; Zappasodi, Filippo; Barbati, Giulia; Salustri, Carlo; Pizzella, Vittorio; Rossini, Paolo Maria; Tecchio, Franca

    2006-07-26

    In this paper, we present a magnetoencephalographic study of the fetal auditory response to external stimuli and to the sound of the mother's heartbeat. We describe how an ad hoc functional selection procedure allowed us to isolate the sources in the fetal brain responding to sounds only, after the application to the recorded data of a standard Independent Component Analysis algorithm. In our experiment, acoustic stimuli were delivered to twelve healthy women with uncomplicated pregnancies at a time between 36 and 40 weeks gestational age, with their fetuses in breech presentation. Ultrasound images allowed determination of the region over the women's abdomen nearest to the fetal head, over which both the acoustic stimulator and the MEG sensors were subsequently placed. In 8 out of the 12 cases, our analysis provided consistent evidence of a fetal response both to the mother's heartbeat and to the external auditory stimulation; both were characterized by a clear prominent component at around 200 ms latency, which is widely accepted as the marker of the fetal response to auditory stimuli.

  19. A novel approach for the averaging of magnetocardiographically recorded heart beats

    Energy Technology Data Exchange (ETDEWEB)

    DiPietroPaolo, D [Advanced Technologies Biomagnetics, Pescara (Italy); Mueller, H-P [Division for Biosignals and Imaging Technologies, Central Institute for Biomedical Engineering, Ulm University, D-89069 Ulm (Germany); Erne, S N [Division for Biosignals and Imaging Technologies, Central Institute for Biomedical Engineering, Ulm University, D-89069 Ulm (Germany)

    2005-05-21

    Performing signal averaging in an efficient and correct way is indispensable since it is a prerequisite for a broad variety of magnetocardiographic (MCG) analysis methods. One of the most common procedures for performing the signal averaging to increase the signal-to-noise ratio (SNR) in magnetocardiography, as well as in electrocardiography (ECG), is done by means of spatial or temporal techniques. In this paper, an improvement of the temporal averaging method is presented. In order to obtain an accurate signal detection, temporal alignment methods and objective classification criteria are developed. The processing technique based on hierarchical clustering is introduced to take into account the non-stationarity of the noise and, to some extent, the biological variability of the signals reaching the optimum SNR. The method implemented is especially designed to run fast and does not require any interaction from the operator. The averaging procedure described in this work is applied to the averaging of MCG data as an example, but with its intrinsic properties it can also be applied to the averaging of ECG recording, averaging of body-surface-potential mapping (BSPM) and averaging of magnetoencephalographic (MEG) or electroencephalographic (EEG) signals.

  20. Imminent brain death: Point of departure for potential heart-beating organ donor recognition

    NARCIS (Netherlands)

    Y.J. de Groot (Yorick); N.E. Jansen (Nichon); J. Bakker (Jan); M.A. Kuiper (Michael); S. Aerdts (Stan); A.I.R. Maas (Andrew); E.F.M. Wijdicks (Eelco); H.A. van Leiden (Hendrik); A.J. Hoitsma (Andries); H.P.H. Kremer (Berry); E.J.O. Kompanje (Erwin)

    2010-01-01

    textabstractPurpose: There is, in European countries that conduct medical chart review of intensive care unit (ICU) deaths, no consensus on uniform criteria for defining a potential organ donor. Although the term is increasingly being used in recent literature, it is seldom defined in detail. We

  1. Imminent brain death : point of departure for potential heart-beating organ donor recognition

    NARCIS (Netherlands)

    de Groot, Yorick J.; Jansen, Nichon E.; Bakker, Jan; Kuiper, Michael A.; Aerdts, Stan; Maas, Andrew I. R.; Wijdicks, Eelco F. M.; van Leiden, Hendrik A.; Hoitsma, Andries J.; Kremer, Berry H. P. H.; Kompanje, Erwin J. O.

    There is, in European countries that conduct medical chart review of intensive care unit (ICU) deaths, no consensus on uniform criteria for defining a potential organ donor. Although the term is increasingly being used in recent literature, it is seldom defined in detail. We searched for criteria

  2. Imminent brain death: point of departure for potential heart-beating organ donor recognition.

    NARCIS (Netherlands)

    Groot, Y.J. de; Jansen, N.E.; Bakker, J.; Kuiper, M.A.; Aerdts, S.; Maas, A.I.; Wijdicks, E.F.; Leiden, H.A. van; Hoitsma, A.J.; Kremer, H.P.H.; Kompanje, E.J.

    2010-01-01

    PURPOSE: There is, in European countries that conduct medical chart review of intensive care unit (ICU) deaths, no consensus on uniform criteria for defining a potential organ donor. Although the term is increasingly being used in recent literature, it is seldom defined in detail. We searched for

  3. Make the call, don't miss a beat: Heart Attack Information for Women

    Science.gov (United States)

    ... Carpal tunnel syndrome Depression Irritable bowel syndrome Migraine Thyroid disease Urinary tract infections All A-Z health topics ... Carpal tunnel syndrome Depression Irritable bowel syndrome Migraine Thyroid disease Urinary tract infections All A-Z health topics ...

  4. Effects of radiographic contrast media on cellular electrophysiology in the beating heart

    Energy Technology Data Exchange (ETDEWEB)

    Wolpers, H.G.; Baller, D.; Ensink, F.B.M.; Hoeft, A.; Korb, H.; Hellige, G.

    1982-01-01

    Electrophysiological effects of intracoronarily administered contrast media have been documented in 12 thoracotomized dogs at the cellular level by use of a modified microelectrode technique. Injections (n = 63) of 4 different contrast media uniformly led to a temporary cellular hyperpolarisation of the resting potential and prolongation of the action potential. Additional experiments with intracoronary injections of several electrolyte concentrations, mainly by a local deficiency of potassium ions and an excess of sodium ions. The significance of the findings for mechanisms underlying ECG-changes and ventricular arrhythmia by radiographic contrasts media will be discussed.

  5. Mimo pillow--an intelligent cushion designed with maternal heart beat vibrations for comforting newborn infants.

    Science.gov (United States)

    Chen, Wei; Oetomo, Sidarto Bambang; Tetteroo, Daniel; Versteegh, Frank; Mamagkaki, Thelxi; Pereira, Mariana Serras; Janssen, Lindy; van Meurs, Andrea

    2015-05-01

    Premature infants are subject to numerous interventions ranging from a simple diaper change to surgery while residing in neonatal intensive care units. These neonates often suffer from pain, distress, and discomfort during the first weeks of their lives. Although pharmacological pain treatment often is available, it cannot always be applied to relieve a neonate from pain or discomfort. This paper describes a nonpharmacological solution, called Mimo, which provides comfort through mediation of a parent's physiological features to the distressed neonate via an intelligent pillow system embedded with sensing and actuating functions. We present the design, the implementation, and the evaluation of the prototype. Clinical tests at Máxima Medical Center in the Netherlands show that among the nine of ten infants who showed discomfort following diaper change, a shorter recovery time to baseline skin conductance analgesimeter values could be measured when the maternal heartbeat vibration in the Mimo was switched ON and in seven of these ten a shorter crying time was measured.

  6. A tiny heart beating: Student-edited legal periodicals in good ol' Europe

    OpenAIRE

    Russi, L.; Longobardi, F.

    2009-01-01

    This paper has a twofold aim: to analyze the possible opportunities disclosed by the observed growth of student- dited law reviews in Europe and to propose an innovative model of student participation to legal publication. The first part explores the phenomenon of student-edited law reviews in the U.S., focusing on its recognized educational benefits. Among others, it is observed that participation in student-edited law reviews might promote greater scholarly maturity among J.D. students, who...

  7. "My Heart Beats in Two Places": Immigration Stories in Korean-American Picture Books

    Science.gov (United States)

    Yi, Joanne H.

    2014-01-01

    This article examines the impact of immigration on Korean children through a content and literary analysis of 14 children's picture books. A majority of published children's literature dealing with the subject of Korean Americans or Korean immigration contains culturally specific themes common to the Korean immigration experience. These…

  8. Heart transplantation from donation after circulatory determined death

    Science.gov (United States)

    Page, Aravinda; Messer, Simon

    2018-01-01

    Fifty years since the first successful human heart transplant from a non-heart beating donor, this concept of heart transplantation from donation after circulatory determined death (DCD) promises to be one of the most exciting developments in heart transplantation. Heart transplantation has established itself as the best therapeutic option for patients with end-stage heart failure, with the opportunity to provide these patients with a near-normal quality of life. However, this treatment is severely limited by the availability of suitable donor hearts. In recent times, heart transplantation has been limited to using donor hearts from donors following brain stem death. The use of donor hearts from DCD had been thought to be associated with high risk and poor outcomes until recent developments in organ perfusion and retrieval techniques have shown that this valuable resource may provide an answer to the global shortage of suitable donor hearts. With established DCD heart transplant programmes reporting encouraging results, this technique has been shown to be comparable to the current gold standard of donation after brain death (DBD) heart transplantation. PMID:29492385

  9. Risk of 22q11.2 deletion in fetuses with right aortic arch and without intracardiac anomalies.

    Science.gov (United States)

    Perolo, A; De Robertis, V; Cataneo, I; Volpe, N; Campobasso, G; Frusca, T; Ghi, T; Prandstraller, D; Pilu, G; Volpe, P

    2016-08-01

    To assess the risk of 22q11.2 deletion in fetuses with a prenatal diagnosis of right aortic arch without intracardiac anomalies (RAA-no ICA). This was a retrospective study of all fetuses with RAA-no ICA diagnosed prenatally at three referral centers, between 2004 and 2014. A detailed sonographic examination was performed in each case, including visualization of the thymus and of the head and neck vessels to identify the presence of an aberrant left subclavian artery (ALSA). Karyotyping and fluorescence in situ hybridization analysis for diagnosis of 22q11.2 deletion were always offered either prenatally or postnatally. Clinical and echocardiographic examinations were performed in livebirths and a postmortem examination in cases of termination of pregnancy. During the study period, 85 fetuses were diagnosed prenatally with RAA-no ICA. Genetic or clinical data were not available for three cases and these were excluded from analysis. 22q11.2 deletion was found in 7/82 cases (8.5% (95% CI, 3.8-17.3%)). The thymus was small or non-visualized in all seven cases and additional abnormal sonographic findings were present in four. 22q11.2 deletion is present in a clinically significant proportion of fetuses with a prenatal diagnosis of RAA-no ICA. In such cases, a detailed sonographic examination, with assessment of the thymus in particular, may be useful to further define the level of risk for 22q11.2 deletion. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

  10. Utility of intracardiac echocardiography for catheter ablation of complex cardiac arrhythmias in a medium-volume training center.

    Science.gov (United States)

    Filgueiras-Rama, David; de Torres-Alba, Fernando; Castrejón-Castrejón, Sergio; Estrada, Alejandro; Figueroa, Jorge; Salvador-Montañés, Óscar; López, Teresa; Moreno-Yanguela, Mar; López Sendón, José L; Merino, José L

    2015-04-01

    New electrophysiology tools like intracardiac echocardiography (ICE) might help to minimize and early detect complications during cardiac ablation procedures. The aim of the study was to assess the utility and vascular safety of ICE during catheter ablation of complex cardiac arrhythmias in a medium-volume training center. Prospective, observational study consisted of consecutive patients who underwent catheter-based ablation of complex cardiac arrhythmias. All procedures were performed using three-dimensional electro-anatomical mapping and routine cannulation of right and left femoral veins. The ICE probe was initially positioned at the mid-level of the right atrium and properly moved to monitor different steps of the procedure and identify complications. All procedure-related vascular complications were registered. One hundred two patients (age 61.4 ± 13.1 years, 69 male) underwent 110 ablation procedures. Pulmonary vein isolation was the most common ablation substrate (55.4%). Ventricular tachycardia (17.2%) and left atrial flutter procedures (16.4%) were also common. The use of ICE enabled us to early initiate anticoagulation and to optimize the transseptal puncture. It also provided the capability to early detect life-threatening complications such as tamponade (3.6%), along with important information during the procedure such as exact catheter location, lesion formation, and stability during radiofrequency delivery. Such benefits were not associated with a higher number of vascular complications. The use of ICE during catheter-based ablation of complex cardiac substrates provides technical features that may decrease complications and increase accuracy while applying radiofrequency, especially in training centers where fellows start to perform complex procedures. © 2014, Wiley Periodicals, Inc.

  11. Estimation of Human Heart Activity Using Ensemble Kalman Filter

    Directory of Open Access Journals (Sweden)

    Pradhnya Arun Priyadarshi

    2017-02-01

    Full Text Available Heart beat measurement techniques come across various challenges. Electrocardiogram (ECG obtained sometimes does not reveal complete information about electrochemical activity of human heart, because of which functioning of heart cannot be studied properly. In this paper Ensemble Kalman Filter (EnKF is used to generate ECG signal efficiently with better accuracy such that the drawbacks of current techniques are eliminated. Here EnKF is applied to second order mathematical model of human heart, input applied to this mathematical model is a pacemaker signal. The initial values of heart muscle movements and electrochemical activity as a discrete data set are used and prediction steps are commenced. EnKF uses ensemble integration technique to model error statistics which helps obtaining more precise output. The results are obtained with negligible sum squared error, therefore the ECG obtained using EnKF can diagnose the disease related to heart with better accuracy.

  12. Gender- and age-related differences in heart rate dynamics: are women more complex than men?

    Science.gov (United States)

    Ryan, S. M.; Goldberger, A. L.; Pincus, S. M.; Mietus, J.; Lipsitz, L. A.

    1994-01-01

    OBJECTIVES. This study aimed to quantify the complex dynamics of beat-to-beat sinus rhythm heart rate fluctuations and to determine their differences as a function of gender and age. BACKGROUND. Recently, measures of heart rate variability and the nonlinear "complexity" of heart rate dynamics have been used as indicators of cardiovascular health. Because women have lower cardiovascular risk and greater longevity than men, we postulated that there are important gender-related differences in beat-to-beat heart rate dynamics. METHODS. We analyzed heart rate dynamics during 8-min segments of continuous electrocardiographic recording in healthy young (20 to 39 years old), middle-aged (40 to 64 years old) and elderly (65 to 90 years old) men (n = 40) and women (n = 27) while they performed spontaneous and metronomic (15 breaths/min) breathing. Relatively high (0.15 to 0.40 Hz) and low (0.01 to 0.15 Hz) frequency components of heart rate variability were computed using spectral analysis. The overall "complexity" of each heart rate time series was quantified by its approximate entropy, a measure of regularity derived from nonlinear dynamics ("chaos" theory). RESULTS. Mean heart rate did not differ between the age groups or genders. High frequency heart rate power and the high/low frequency power ratio decreased with age in both men and women (p gender-as well as age-related differences in heart rate dynamics. Whether these gender differences are related to lower cardiovascular disease risk and greater longevity in women requires further study.

  13. An EPROM-based heart-rate meter with wide range and multifunctions.

    Science.gov (United States)

    Zhang, K; Zheng, E; Peng, C

    1992-03-01

    A digital heart-rate meter has been developed to display instantaneous as well as average heart-rate of 4 or 8 beats. The display resolution is 1 beat min-1 (BPM) in the range of 13-362 BPM, and 8 BPM in the range of up to 999 BPM. The whole circuit consists of 10 general-purpose integrated circuits (including LCDs). Two EPROM 2716 chips are preprogrammed with heart-rate data. A 12-bit binary counter, which sums the clock pulses between beat-to-beat intervals, is used to address the EPROMs to send appropriate data to the LCD display. We conclude that, with the resolution of 1 BPM, the relationship between the counting clock frequency f and upper display limit f' and lower display limit f" are: f' approximately square root 60f; f" = 60f/Nmax Where Nmax is the capacity of the EPROMs. To extend the dislay range, two clock frequencies, i.e. 256 Hz and 2048 Hz, are generated and switched automatically according to the heart-rate measured. The former is for the heart-rate less than 120 BPM, and the latter is for that higher than 120BPM.

  14. Intracranial electroencephalography power and phase synchronization changes during monaural and binaural beat stimulation.

    Science.gov (United States)

    Becher, Ann-Katrin; Höhne, Marlene; Axmacher, Nikolai; Chaieb, Leila; Elger, Christian E; Fell, Juergen

    2015-01-01

    Auditory stimulation with monaural or binaural auditory beats (i.e. sine waves with nearby frequencies presented either to both ears or to each ear separately) represents a non-invasive approach to influence electrical brain activity. It is still unclear exactly which brain sites are affected by beat stimulation. In particular, an impact of beat stimulation on mediotemporal brain areas could possibly provide new options for memory enhancement or seizure control. Therefore, we examined how electroencephalography (EEG) power and phase synchronization are modulated by auditory stimulation with beat frequencies corresponding to dominant EEG rhythms based on intracranial recordings in presurgical epilepsy patients. Monaural and binaural beat stimuli with beat frequencies of 5, 10, 40 and 80 Hz and non-superposed control signals were administered with low amplitudes (60 dB SPL) and for short durations (5 s). EEG power was intracranially recorded from mediotemporal, temporo-basal and temporo-lateral and surface sites. Evoked and total EEG power and phase synchronization during beat vs. control stimulation were compared by the use of Bonferroni-corrected non-parametric label-permutation tests. We found that power and phase synchronization were significantly modulated by beat stimulation not only at temporo-basal, temporo-lateral and surface sites, but also at mediotemporal sites. Generally, more significant decreases than increases were observed. The most prominent power increases were seen after stimulation with monaural 40-Hz beats. The most pronounced power and synchronization decreases resulted from stimulation with monaural 5-Hz and binaural 80-Hz beats. Our results suggest that beat stimulation offers a non-invasive approach for the modulation of intracranial EEG characteristics. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  15. Intracardiac echo-guided radiofrequency catheter ablation of atrial fibrillation in patients with atrial septal defect or patent foramen ovale repair: a feasibility, safety, and efficacy study.

    Science.gov (United States)

    Lakkireddy, Dhanunjaya; Rangisetty, Umamahesh; Prasad, Subramanya; Verma, Atul; Biria, Mazda; Berenbom, Loren; Pimentel, Rhea; Emert, Martin; Rosamond, Thomas; Fahmy, Tamer; Patel, Dimpi; Di Biase, Luigi; Schweikert, Robert; Burkhardt, David; Natale, Andrea

    2008-11-01

    Intracardiac Echo-Guided Radiofrequency Catheter. Patients with atrial septal defect (ASD) are at higher risk for atrial fibrillation (AF) even after repair. Transseptal access in these patients is perceived to be difficult. We describe the feasibility, safety, and efficacy of pulmonary vein antral isolation (PVAI) in these patients. We prospectively compared post-ASD/patent foramen ovale (PFO) repair patients (group I, n = 45) with age-gender-AF type matched controls (group II, n = 45). All the patients underwent PVAI through a double transseptal puncture with a roving circular mapping catheter technique guided by intracardiac echocardiography (ICE). The short-term (3 months) and long-term (12 month) failure rates were assessed. In group I, 23 (51%) had percutaneous closure devices and 22 (49%) had a surgical closure. There was no significant difference between group I and II in the baseline characteristics. Intracardiac echo-guided double transseptal access was obtained in 98% of patients in group I and in 100% of patients in group II. PVAI was performed in all patients, with right atrial flutter ablation in 7 patients in group I and in 4 patients in group II. Over a mean follow-up of 15 +/- 4 months, group I had higher short-term (18% vs 13%, P = 0.77) and long-term recurrence (24% vs 18%, P = 0.6) than group II. There was no significant difference in the perioperative complications between the two groups. Echocardiography at 3 months showed interatrial communication in 2 patients in group I and 1 patient in group II, which resolved at 12 months. Percutaneous AF ablation using double transseptal access is feasible, safe, and efficacious in patients with ASD and PFO repairs.

  16. A protocol to study ex vivo mouse working heart at human-like heart rate.

    Science.gov (United States)

    Feng, Han-Zhong; Jin, Jian-Ping

    2018-01-01

    Genetically modified mice are widely used as experimental models to study human heart function and diseases. However, the fast rate of normal mouse heart at 400-600bpm limits its capacity of assessing kinetic parameters that are important for the physiology and pathophysiology of human heart that beats at a much slower rate (75-180bpm). To extend the value of mouse models, we established a protocol to study ex vivo mouse working hearts at a human-like heart rate. In the presence of 300μM lidocaine to lower pacemaker and conductive activities and prevent arrhythmia, a stable rate of 120-130bpm at 37°C is achieved for ex vivo mouse working hearts. The negative effects of decreased heart rate on force-frequency dependence and lidocaine as a myocardial depressant on intracellular calcium can be compensated by using a higher but still physiological level of calcium (2.75mM) in the perfusion media. Multiple parameters were studied to compare the function at the human-like heart rate with that of ex vivo mouse working hearts at the standard rate of 480bpm. The results showed that the conditions for slower heart rate in the presence of 300μM lidocaine did not have depressing effect on left ventricular pressure development, systolic and diastolic velocities and stroke volume with maintained positive inotropic and lusitropic responses to β-adrenergic stimulation. Compared with that at 480bpm, the human-like heart rate increased ventricular filling and end diastolic volume with enhanced Frank-Starling responses. Coronary perfusion was increased from longer relaxation time and interval between beats whereas cardiac efficiency was significantly improved. Although the intrinsic differences between mouse and human heart remain, this methodology for ex vivo mouse hearts to work at human-like heart rate extends the value of using genetically modified mouse models to study cardiac function and human heart diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Diminution of Heart Rate Variability in Bipolar Depression

    Directory of Open Access Journals (Sweden)

    Brandon Hage

    2017-12-01

    Full Text Available Autonomic nervous system (ANS dysregulation in depression is associated with symptoms associated with the ANS. The beat-to-beat pattern of heart rate defined as heart rate variability (HRV provides a noninvasive portal to ANS function and has been proposed to represent a means of quantifying resting vagal tone. We quantified HRV in bipolar depressed (BDD patients as a measure of ANS dysregulation seeking to establish HRV as a potential diagnostic and prognostic biomarker for treatment outcome. Forty-seven BDD patients were enrolled. They were randomized to receive either escitalopram–celecoxib or escitalopram-placebo over 8 weeks in a double-blind study design. Thirty-five patients completed the HRV studies. Thirty-six healthy subjects served as controls. HRV was assessed at pretreatment and end of study and compared with that of controls. HRV was quantified and corrected for artifacts using an algorithm that incorporates time and frequency domains to address non-stationarity of the beat-to-beat heart rate pattern. Baseline high frequency-HRV (i.e., respiratory sinus arrhythmia was lower in BDD patients than controls, although the difference did not reach significance. Baseline low-frequency HRV was significantly lower in BDD patients (ln4.20 than controls (ln = 5.50 (p < 0.01. Baseline heart period was significantly shorter (i.e., faster heart rate in BDD patients than controls. No significant change in HRV parameters were detected over the course of the study with either treatment. These findings suggest that components of HRV may be diminished in BDD patients.

  18. Frequency Dynamics of the First Heart Sound

    Science.gov (United States)

    Wood, John Charles

    Cardiac auscultation is a fundamental clinical tool but first heart sound origins and significance remain controversial. Previous clinical studies have implicated resonant vibrations of both the myocardium and the valves. Accordingly, the goals of this thesis were threefold, (1) to characterize the frequency dynamics of the first heart sound, (2) to determine the relative contribution of the myocardium and the valves in determining first heart sound frequency, and (3) to develop new tools for non-stationary signal analysis. A resonant origin for first heart sound generation was tested through two studies in an open-chest canine preparation. Heart sounds were recorded using ultralight acceleration transducers cemented directly to the epicardium. The first heart sound was observed to be non-stationary and multicomponent. The most dominant feature was a powerful, rapidly-rising frequency component that preceded mitral valve closure. Two broadband components were observed; the first coincided with mitral valve closure while the second significantly preceded aortic valve opening. The spatial frequency of left ventricular vibrations was both high and non-stationary which indicated that the left ventricle was not vibrating passively in response to intracardiac pressure fluctuations but suggested instead that the first heart sound is a propagating transient. In the second study, regional myocardial ischemia was induced by left coronary circumflex arterial occlusion. Acceleration transducers were placed on the ischemic and non-ischemic myocardium to determine whether ischemia produced local or global changes in first heart sound amplitude and frequency. The two zones exhibited disparate amplitude and frequency behavior indicating that the first heart sound is not a resonant phenomenon. To objectively quantify the presence and orientation of signal components, Radon transformation of the time -frequency plane was performed and found to have considerable potential for pattern

  19. Heart Failure

    DEFF Research Database (Denmark)

    Jorsal, Anders; Wiggers, Henrik; McMurray, John J V

    2018-01-01

    This article briefly discusses the epidemiology of heart failure and diabetes and summarizes the key findings from the recent cardiovascular outcome trials in patients with type 2 diabetes, with a focus on heart failure as an endpoint.......This article briefly discusses the epidemiology of heart failure and diabetes and summarizes the key findings from the recent cardiovascular outcome trials in patients with type 2 diabetes, with a focus on heart failure as an endpoint....

  20. [The effect of public defense of a doctoral thesis on the heart rate of the doctoral candidate].

    Science.gov (United States)

    Kiljander, Toni; Toikka, Jyri; Koskenvuo, Juha; Jaakkola, Ilkka

    2011-01-01

    The effect of public defense of a doctoral thesis on the heart rate of the doctoral candidate Most doctoral candidates find the public defense of a doctoral thesis an exciting and stressful experience. In this study, Holter recording during the defense was made for four doctoral candidates of the Faculty of Medicine. Maximum heart rate among the subjects was on the average 172 beats/min with a median heart rate of 116 beats/min. Sympathicotonia and release of stress hormones associated with the defense raise the heart rate to levels that may be very high for several hours. This is a risk factor for a coronary event and should be considered, if the doctoral candidate has coronary heart disease, carries risk factors for coronary heart disease, or is an elderly person.

  1. Heart attack

    Science.gov (United States)

    ... part in support groups for people with heart disease . Outlook (Prognosis) After a heart attack, you have a higher ... P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine . 10th ed. Philadelphia, PA: Elsevier Saunders; 2014: ...

  2. Beat processing is pre-attentive for metrically simple rhythms with clear accents: an ERP study.

    Directory of Open Access Journals (Sweden)

    Fleur L Bouwer

    Full Text Available The perception of a regular beat is fundamental to music processing. Here we examine whether the detection of a regular beat is pre-attentive for metrically simple, acoustically varying stimuli using the mismatch negativity (MMN, an ERP response elicited by violations of acoustic regularity irrespective of whether subjects are attending to the stimuli. Both musicians and non-musicians were presented with a varying rhythm with a clear accent structure in which occasionally a sound was omitted. We compared the MMN response to the omission of identical sounds in different metrical positions. Most importantly, we found that omissions in strong metrical positions, on the beat, elicited higher amplitude MMN responses than omissions in weak metrical positions, not on the beat. This suggests that the detection of a beat is pre-attentive when highly beat inducing stimuli are used. No effects of musical expertise were found. Our results suggest that for metrically simple rhythms with clear accents beat processing does not require attention or musical expertise. In addition, we discuss how the use of acoustically varying stimuli may influence ERP results when studying beat processing.

  3. Direct Visualization of Mechanical Beats by Means of an Oscillating Smartphone

    Science.gov (United States)

    Giménez, Marcos H.; Salinas, Isabel; Monsoriu, Juan A.; Castro-Palacio, Juan C.

    2017-10-01

    The resonance phenomenon is widely known in physics courses. Qualitatively speaking, resonance takes place in a driven oscillating system whenever the frequency approaches the natural frequency, resulting in maximal oscillatory amplitude. Very closely related to resonance is the phenomenon of mechanical beating, which occurs when the driving and natural frequencies of the system are slightly different. The frequency of the beat is just the difference of the natural and driving frequencies. Beats are very familiar in acoustic systems. There are several works in this journal on visualizing the beats in acoustic systems. For instance, the microphone and the speaker of two mobile devices were used in previous work to analyze the acoustic beats produced by two signals of close frequencies. The formation of beats can also be visualized in mechanical systems, such as a mass-spring system or a double-driven string. Here, the mechanical beats in a smartphone-spring system are directly visualized in a simple way. The frequency of the beats is measured by means of the acceleration sensor of a smartphone, which hangs from a spring attached to a mechanical driver. This laboratory experiment is suitable for both high school and first-year university physics courses.

  4. Training with Rhythmic Beat Gestures Benefits L2 Pronunciation in Discourse-Demanding Situations

    Science.gov (United States)

    Gluhareva, Daria; Prieto, Pilar

    2017-01-01

    Recent research has shown that beat gestures (hand gestures that co-occur with speech in spontaneous discourse) are temporally integrated with prosodic prominence and that they help word memorization and discourse comprehension. However, little is known about the potential beneficial effects of beat gestures in second language (L2) pronunciation…

  5. Beat-wave laser accelerators, further comment including note on the 'Surfatron' concept

    International Nuclear Information System (INIS)

    Lawson, J.D.

    1984-07-01

    The paper deals with the Rutherford Appleton Laboratory (RAL) study of the beat-wave particle accelerator, intended for high energy physics. Three factors; the build-up of beat-wave, the surfatron concept and the self-focusing effects are considered in the context of the RAL study. (U.K.)

  6. Simple non-invasive analysis of embryonic stem cell-derived cardiomyocytes beating in vitro.

    Science.gov (United States)

    Radaszkiewicz, Katarzyna Anna; Sýkorová, Dominika; Karas, Pavel; Kudová, Jana; Kohút, Lukáš; Binó, Lucia; Večeřa, Josef; Víteček, Jan; Kubala, Lukáš; Pacherník, Jiří

    2016-02-01

    The analysis of digital video output enables the non-invasive screening of various active biological processes. For the monitoring and computing of the beating parameters of cardiomyocytes in vitro, CB Analyser (cardiomyocyte beating analyser) software was developed. This software is based on image analysis of the video recording of beating cardiomyocytes. CB Analyser was tested using cardiomyocytes derived from mouse embryonic stem cells at different stages of cardiomyogenesis. We observed that during differentiation (from day 18), the beat peak width decreased, which corresponded to the increased speed of an individual pulse. However, the beating frequency did not change. Further, the effects of epinephrine modulating mature cardiomyocyte functions were tested to validate the CB Analyser analysis. In conclusion, data show that CB Analyser is a useful tool for evaluating the functions of both developing and mature cardiomyocytes under various conditions in vitro.

  7. Auditory beat stimulation and its effects on cognition and mood States.

    Science.gov (United States)

    Chaieb, Leila; Wilpert, Elke Caroline; Reber, Thomas P; Fell, Juergen

    2015-01-01

    Auditory beat stimulation may be a promising new tool for the manipulation of cognitive processes and the modulation of mood states. Here, we aim to review the literature examining the most current applications of auditory beat stimulation and its targets. We give a brief overview of research on auditory steady-state responses and its relationship to auditory beat stimulation (ABS). We have summarized relevant studies investigating the neurophysiological changes related to ABS and how they impact upon the design of appropriate stimulation protocols. Focusing on binaural-beat stimulation, we then discuss the role of monaural- and binaural-beat frequencies in cognition and mood states, in addition to their efficacy in targeting disease symptoms. We aim to highlight important points concerning stimulation parameters and try to address why there are often contradictory findings with regard to the outcomes of ABS.

  8. More attentional focusing through binaural beats: evidence from the global-local task.

    Science.gov (United States)

    Colzato, Lorenza S; Barone, Hayley; Sellaro, Roberta; Hommel, Bernhard

    2017-01-01

    A recent study showed that binaural beats have an impact on the efficiency of allocating attention over time. We were interested to see whether this impact affects attentional focusing or, even further, the top-down control over irrelevant information. Healthy adults listened to gamma-frequency (40 Hz) binaural beats, which are assumed to increase attentional concentration, or a constant tone of 340 Hz (control condition) for 3 min before and during a global-local task. While the size of the congruency effect (indicating the failure to suppress task-irrelevant information) was unaffected by the binaural beats, the global-precedence effect (reflecting attentional focusing) was considerably smaller after gamma-frequency binaural beats than after the control condition. Our findings suggest that high-frequency binaural beats bias the individual attentional processing style towards a reduced spotlight of attention.

  9. Simple non-invasive analysis of embryonic stem cell-derived cardiomyocytes beating in vitro

    Science.gov (United States)

    Radaszkiewicz, Katarzyna Anna; Sýkorová, Dominika; Karas, Pavel; Kudová, Jana; Kohút, Lukáš; Binó, Lucia; Večeřa, Josef; Víteček, Jan; Kubala, Lukáš; Pacherník, Jiří

    2016-02-01

    The analysis of digital video output enables the non-invasive screening of various active biological processes. For the monitoring and computing of the beating parameters of cardiomyocytes in vitro, CB Analyser (cardiomyocyte beating analyser) software was developed. This software is based on image analysis of the video recording of beating cardiomyocytes. CB Analyser was tested using cardiomyocytes derived from mouse embryonic stem cells at different stages of cardiomyogenesis. We observed that during differentiation (from day 18), the beat peak width decreased, which corresponded to the increased speed of an individual pulse. However, the beating frequency did not change. Further, the effects of epinephrine modulating mature cardiomyocyte functions were tested to validate the CB Analyser analysis. In conclusion, data show that CB Analyser is a useful tool for evaluating the functions of both developing and mature cardiomyocytes under various conditions in vitro.

  10. The quantum beat principles and applications of atomic clocks

    CERN Document Server

    Major, F

    2007-01-01

    This work attempts to convey a broad understanding of the physical principles underlying the workings of these quantum-based atomic clocks, with introductory chapters placing them in context with the early development of mechanical clocks and the introduction of electronic time-keeping as embodied in the quartz-controlled clocks. While the book makes no pretense at being a history of atomic clocks, it nevertheless takes a historical perspective in its treatment of the subject. Intended for nonspecialists with some knowledge of physics or engineering, The Quantum Beat covers a wide range of salient topics relevant to atomic clocks, treated in a broad intuitive manner with a minimum of mathematical formalism. Detailed descriptions are given of the design principles of the rubidium, cesium, hydrogen maser, and mercury ion standards; the revolutionary changes that the advent of the laser has made possible, such as laser cooling, optical pumping, the formation of "optical molasses," and the cesium "fountain" stand...

  11. MD 979: Beta-beating measurements on colliding beams

    CERN Document Server

    Goncalves Jorge, Patrik; Pieloni, Tatiana; Buffat, Xavier; Carlier, Felix Simon; Coello De Portugal - Martinez Vazquez, Jaime Maria; Fol, Elena; Langner, Andy Sven; Medina Medrano, Luis Eduardo; Olexa, Jakub; Tomas Garcia, Rogelio; Valuch, Daniel; Wegscheider, Andreas; CERN. Geneva. ATS Department

    2017-01-01

    The HL-LHC high brightness beams will give a large β-beating due to the head-on and long-range interactions since a beam-beam parameter of 0.01 per Interaction Point (IP) is expected. The β-heating induced by two head-on collision reaches 15%. A third IP, i.e. IP8, could bring the β-heating up to 24%. The aim of the Machine Development (MD) study was to test optics measurements with AC dipole and ADT on colliding beams at injection and to implement a correction of the β-heating due to to head-on collision in the two experiments IP1&5. Int his note, we summarize the first results of this test performed in the LHC.

  12. The effect of binaural beats on verbal working memory and cortical connectivity

    Science.gov (United States)

    Beauchene, Christine; Abaid, Nicole; Moran, Rosalyn; Diana, Rachel A.; Leonessa, Alexander

    2017-04-01

    Objective. Synchronization in activated regions of cortical networks affect the brain’s frequency response, which has been associated with a wide range of states and abilities, including memory. A non-invasive method for manipulating cortical synchronization is binaural beats. Binaural beats take advantage of the brain’s response to two pure tones, delivered independently to each ear, when those tones have a small frequency mismatch. The mismatch between the tones is interpreted as a beat frequency, which may act to synchronize cortical oscillations. Neural synchrony is particularly important for working memory processes, the system controlling online organization and retention of information for successful goal-directed behavior. Therefore, manipulation of synchrony via binaural beats provides a unique window into working memory and associated connectivity of cortical networks. Approach. In this study, we examined the effects of different acoustic stimulation conditions during an N-back working memory task, and we measured participant response accuracy and cortical network topology via EEG recordings. Six acoustic stimulation conditions were used: None, Pure Tone, Classical Music, 5 Hz binaural beats, 10 Hz binaural beats, and 15 Hz binaural beats. Main results. We determined that listening to 15 Hz binaural beats during an N-Back working memory task increased the individual participant’s accuracy, modulated the cortical frequency response, and changed the cortical network connection strengths during the task. Only the 15 Hz binaural beats produced significant change in relative accuracy compared to the None condition. Significance. Listening to 15 Hz binaural beats during the N-back task activated salient frequency bands and produced networks characterized by higher information transfer as compared to other auditory stimulation conditions.

  13. The effect of binaural beats on verbal working memory and cortical connectivity.

    Science.gov (United States)

    Beauchene, Christine; Abaid, Nicole; Moran, Rosalyn; Diana, Rachel A; Leonessa, Alexander

    2017-04-01

    Synchronization in activated regions of cortical networks affect the brain's frequency response, which has been associated with a wide range of states and abilities, including memory. A non-invasive method for manipulating cortical synchronization is binaural beats. Binaural beats take advantage of the brain's response to two pure tones, delivered independently to each ear, when those tones have a small frequency mismatch. The mismatch between the tones is interpreted as a beat frequency, which may act to synchronize cortical oscillations. Neural synchrony is particularly important for working memory processes, the system controlling online organization and retention of information for successful goal-directed behavior. Therefore, manipulation of synchrony via binaural beats provides a unique window into working memory and associated connectivity of cortical networks. In this study, we examined the effects of different acoustic stimulation conditions during an N-back working memory task, and we measured participant response accuracy and cortical network topology via EEG recordings. Six acoustic stimulation conditions were used: None, Pure Tone, Classical Music, 5 Hz binaural beats, 10 Hz binaural beats, and 15 Hz binaural beats. We determined that listening to 15 Hz binaural beats during an N-Back working memory task increased the individual participant's accuracy, modulated the cortical frequency response, and changed the cortical network connection strengths during the task. Only the 15 Hz binaural beats produced significant change in relative accuracy compared to the None condition. Listening to 15 Hz binaural beats during the N-back task activated salient frequency bands and produced networks characterized by higher information transfer as compared to other auditory stimulation conditions.

  14. Heart Rate Variability - A Historical Perspective

    Directory of Open Access Journals (Sweden)

    George E Billman

    2011-11-01

    Full Text Available Heart rate variability (HRV, the beat-to-beat variation in either heart rate or the duration of the R-R interval – the heart period, has become a popular clinical and investigational tool. The temporal fluctuations in heart rate exhibit a marked synchrony with respiration (increasing during inspiration and decreasing during expiration – the so called respiratory sinus arrhythmia, RSA and are widely believed to reflect changes in cardiac autonomic regulation. Although the exact contributions of the parasympathetic and the sympathetic divisions of the autonomic nervous system to this variability are controversial and remain the subject of active investigation and debate, a number of time and frequency domain techniques have been developed to provide insight into cardiac autonomic regulation in both health and disease. It is the purpose of this essay to provide an historical overview of the evolution in the concept of heart rate variability. Briefly, pulse rate was first measured by ancient Greek physicians and scientists. However, it was not until the invention of the Physician’s Pulse Watch (a watch with a second hand that could be stopped in 1707 that changes in pulse rate could be accurately assessed. The Rev. Stephen Hales (1733 was the first to note that pulse varied with respiration and in 1847 Carl Ludwig was the first to record RSA. With the measurement of the ECG (1895 and advent of digital signal processing techniques in the 1960’s, investigation of HRV and its relationship to health and disease has exploded. This essay will conclude with a brief description of time domain, frequency domain, and non-linear dynamic analysis techniques (and their limitations that are commonly used to measure heart rate variability.

  15. Increased Short-Term Beat-to-Beat QT Interval Variability in Patients with Impaired Glucose Tolerance

    Directory of Open Access Journals (Sweden)

    Andrea Orosz

    2017-06-01

    Full Text Available Prediabetic states and diabetes are important risk factors for cardiovascular morbidity and mortality. Determination of short-term QT interval variability (STVQT is a non-invasive method for assessment of proarrhythmic risk. The aim of the study was to evaluate the STVQT in patients with impaired glucose tolerance (IGT. 18 IGT patients [age: 63 ± 11 years, body mass index (BMI: 31 ± 6 kg/m2, fasting glucose: 6.0 ± 0.4 mmol/l, 120 min postload glucose: 9.0 ± 1.0 mmol/l, hemoglobin A1c (HbA1c: 5.9 ± 0.4%; mean ± SD] and 18 healthy controls (age: 56 ± 9 years, BMI: 27 ± 5 kg/m2, fasting glucose: 5.2 ± 0.4 mmol/l, 120 min postload glucose: 5.5 ± 1.3 mmol/l, HbA1c: 5.4 ± 0.3% were enrolled into the study. ECGs were recorded, processed, and analyzed off-line. The RR and QT intervals were expressed as the average of 30 consecutive beats, the temporal instability of beat-to-beat repolarization was characterized by calculating STVQT as follows: STVQT = Σ|QTn + 1 − QTn| (30x√2−1. Autonomic function was assessed by means of standard cardiovascular reflex tests. There were no differences between IGT and control groups in QT (411 ± 43 vs 402 ± 39 ms and QTc (431 ± 25 vs 424 ± 19 ms intervals or QT dispersion (44 ± 13 vs 42 ± 17 ms. However, STVQT was significantly higher in IGT patients (5.0 ± 0.7 vs 3.7 ± 0.7, P < 0.0001. The elevated temporal STVQT in patients with IGT may be an early indicator of increased instability of cardiac repolarization during prediabetic conditions.

  16. Heart rate and heart rate variability responses to Tai Chi and jogging in Beijing and Graz.

    Science.gov (United States)

    Litscher, Gerhard; Zhang, Weibo; Huang, Tao; Wang, Lu

    2011-02-01

    Tai Chi is a famous training method in China, and jogging is a popular kind of exercise both in Austria and China. Nevertheless, there is little information concerning online monitoring of biosignals during both training activities in parallel. Within the last years innovative scientific monitoring tools for evaluating features of neurocardial fitness have been developed. The goal of this study was to demonstrate heart rate and heart rate variability analysis for the first time during Tai Chi and jogging. Continuous electrocardiographic monitoring over a period of 75 minutes was performed simultaneously in two healthy volunteers using the same type of equipment (medilog AR12 systems). Two healthy persons (both male, 49 years and 52 years, respectively), both hobby sportsmen, were monitored continuously during two resting periods before and after active sport and also during Tai Chi and jogging, respectively. Data acquisition was performed without any technical problems in both subjects. Poincaré plots of sequential R-R intervals (beat to beat variability) show two ellipses of different shape and magnitude. During resting periods blood pressure effects can be clearly seen in one subject (jogging). The same effects, however reduced, are obvious in the other volunteer during Tai Chi. The present investigations during Tai Chi and jogging highlight the potential value of heart rate and heart rate variability monitoring even under difficult conditions. The innovative kind of analysis helps to show how well the human body reacts to sport, stress and recovery.

  17. Electrogramas intracardíacos en tiempo real en el diagnóstico de fallas de marcapasos Real time intracardiac electrograms for the diagnosis of pacemaker malfunction

    Directory of Open Access Journals (Sweden)

    Adrián Baranchuk

    2008-02-01

    Full Text Available El desplazamiento crónico del catéter ventricular es una complicación infrecuente del implante de marcapasos. Es infrecuente que un catéter desplazado sense y capture en una cámara donde no fue implantado originalmente. Se presenta el caso de un paciente con marcapasos doble cámara en el que el catéter ventricular se desplazó hacia la aurícula derecha. El catéter desplazado permite sensar y capturar la aurícula. El diagnóstico inicial se realizó mediante el análisis deductivo conjunto de los electrogramas en tiempo real y los eventos en los canales de registro ("marker channel". La radiografía de tórax confirmó el diagnóstico presuntivo.Chronic ventricular lead dislodgement is an infrequent complication of pacemaker implantation. Occasionally, the dislodged lead may sense and capture a chamber in which the lead was not originally positioned. Intracardiac real time electrograms and channel markers are useful tools for the diagnosis of pacemaker malfunction. We present the case of a patient with a ventricular lead dislodgement into the atrium. The ventricular lead was able to sense and capture the atrium. Initial diagnosis was performed based on the deductive analysis of intracardiac real time electrograms and channel markers and confirmed by chest X-ray.

  18. [Camera-cinematography of the heart (author's transl)].

    Science.gov (United States)

    Adam, W E; Meyer, G; Bitter, F; Kampmann, H; Bargon, G; Stauch, M

    1975-07-01

    By "camera-cinematography" of the heart, we mean an isotope method which permits detailed observation of cardiac mechanics without the use of a catheter. All that is necessary is an intravenous injection of 10 to 15 mCi 99mTc human serum albumen followed after ten minutes by a five to ten minute period of observation with a scintilation camera. At this time the isotope has become distributed in the blood. Variations in the precordial impulses correspond with intra-cardiac changes of blood volume during a cardiac cycle. Analysis of the R-wave provides adequate information of cyclical volume changes in limited portions of the heart. This is achieved by a monitor with a pseudo-3-dimensional display; contraction and relaxation of the myocardium can be shown for any chosen longitudinal or horizontal diameter of the heart. Our programme allows simultaneous presentation of the movement of any point on the myocardium as a time-activity curve. The method is recommended as an addition to chest radiography, heart screening or cardiac kymography before carrying out cardiac catheterisation.

  19. Identification of low and high frequency ranges for heart rate variability and blood pressure variability analyses using pharmacological autonomic blockade with atropine and propranolol in swine.

    Science.gov (United States)

    Poletto, Rosangela; Janczak, Andrew M; Marchant-Forde, Ruth M; Marchant-Forde, Jeremy N; Matthews, Donald L; Dowell, Carol A; Hogan, Daniel F; Freeman, Lynetta J; Lay, Donald C

    2011-05-03

    Understanding autonomic nervous system functioning, which mediates behavioral and physiological responses to stress, offers great potential for assessing farm animal stress and welfare. Evaluation of heart rate variability (HRV) and blood pressure variability (BPV), using time and frequency domain analyses may provide a sensitive and reliable measure of affective states and stress-mediated changes in sympathetic and parasympathetic tones. The aim of this research was to define low (LF) and high frequency (HF) power spectral ranges using pharmacological autonomic blockade, and to examine HRV and BPV parameter changes in response to atropine and propranolol in swine. Ten, 13-week old, barrows (n=6) and gilts (n=4) underwent surgery to place an intra-cardiac electrode and a blood pressure catheter attached to a biotelemetric transmitter; pigs had a 3-week recovery period prior to data collection. Each pig was subjected to administration of 4 intravenous (i.v.) drug treatments: a control treatment, 3 mL of saline, and 3 blockade treatments; 0.1 mg/kg of atropine, 1.0 mg/kg of propranolol, and .1 mg/kg of atropine together with 1.0 mg/kg of propranolol. All treatments were delivered by injection in the jugular vein with a minimum of 48 h between individual treatments. Behavior, ECG and blood pressure data were recorded continuously for a total of 1h, from 30 min pre-injection to 30 min post-injection. For data analyses, two 512-beat intervals were selected for each treatment while the pig was lying and inactive. The first interval was selected from the pre-injection period (baseline), and the second was selected between 10 and 30 min post-injection. Time and frequency domain (power spectral density) analyses were performed on each data interval. Subsequent, LF and HF bands from the power spectral densities were defined based on general linear and regression analyses. The HRV and BPV were computed with a covariate (baseline) factorial analysis of treatment by sex

  20. Effect of pre operative heart rate on post spinal hypotension in obsteric patients

    International Nuclear Information System (INIS)

    Khan, S.; Zahoor, M.U.; Zaid, A.Y.; Buland, K.

    2010-01-01

    The purpose of the study was to determine the association between of preoperative heart rate and post spinal hypotension in women undergoing cesarean section, Two hundred patients undergoing caesarean were included in the study selected on non probability convenience sampling technique, The patients were divided into two groups depending upon their pre operative heart rate. Spinal anesthesia was administered and number of patients developing hypotension was noted. Among 200 patients, who were included in the study; 112 were placed in group A and 88 were placed in group B depending on mean heart rate of 90 beats per minute or less or 91 beats per minute or more respectively. In group A 14 (11.86%) patients developed hypotension where as in group B 28 (31,82%) patients developed hypotension. Pre operative heart rate is significantly associated with post spinal hypotension in obstetric patients undergoing cesarean section. (author)

  1. Plasma protein concentration and control of coronary vascular resistance in isolated rat heart

    NARCIS (Netherlands)

    Avolio, A. P.; Spaan, J. A.; Laird, J. D.

    1980-01-01

    Isolated externally paced (300 beats/min) rat hearts were perfused at constant pressure (70 mmHg) using a modified Krebs-Henseleit solution with (n = 52) and without (n = 15) washed bovine red cells. Albumin concentration varied from 1 to 10 g/dl. With increasing albumin concentration in

  2. Functional imaging of murine hearts using accelerated self-gated UTE cine MRI

    NARCIS (Netherlands)

    Motaal, Abdallah G.; Noorman, Nils; de Graaf, Wolter L.; Hoerr, Verena; Florack, Luc M. J.; Nicolay, Klaas; Strijkers, Gustav J.

    2015-01-01

    We introduce a fast protocol for ultra-short echo time (UTE) Cine magnetic resonance imaging (MRI) of the beating murine heart. The sequence involves a self-gated UTE with golden-angle radial acquisition and compressed sensing reconstruction. The self-gated acquisition is performed asynchronously

  3. Accelerated high-frame-rate mouse heart cine-MRI using compressed sensing reconstruction

    NARCIS (Netherlands)

    Motaal, Abdallah G.; Coolen, Bram F.; Abdurrachim, Desiree; Castro, Rui M.; Prompers, Jeanine J.; Florack, Luc M. J.; Nicolay, Klaas; Strijkers, Gustav J.

    2013-01-01

    We introduce a new protocol to obtain very high-frame-rate cinematographic (Cine) MRI movies of the beating mouse heart within a reasonable measurement time. The method is based on a self-gated accelerated fast low-angle shot (FLASH) acquisition and compressed sensi ng reconstruction. Key to our

  4. Effects of single cycle binaural beat duration on auditory evoked potentials.

    Science.gov (United States)

    Mihajloski, Todor; Bohorquez, Jorge; Özdamar, Özcan

    2014-01-01

    Binaural beat (BB) illusions are experienced as continuous central pulsations when two sounds with slightly different frequencies are delivered to each ear. It has been shown that steady-state auditory evoked potentials (AEPs) to BBs can be captured and investigated. The authors recently developed a new method of evoking transient AEPs to binaural beats using frequency modulated stimuli. This methodology was able to create single BBs in predetermined intervals with varying carrier frequencies. This study examines the effects of the BB duration and the frequency modulating component of the stimulus on the binaural beats and their evoked potentials. Normal hearing subjects were tested with a set of four durations (25, 50, 100, and 200 ms) with two stimulation configurations, binaural dichotic (binaural beats) and diotic (frequency modulation). The results obtained from the study showed that out of the given durations, the 100 ms beat, was capable of evoking the largest amplitude responses. The frequency modulation effect showed a decrease in peak amplitudes with increasing beat duration until their complete disappearance at 200 ms. Even though, at 200 ms, the frequency modulation effects were not present, the binaural beats were still perceived and captured as evoked potentials.

  5. The effect of beat frequency on eye movements during free viewing.

    Science.gov (United States)

    Maróti, Emese; Knakker, Balázs; Vidnyánszky, Zoltán; Weiss, Béla

    2017-02-01

    External periodic stimuli entrain brain oscillations and affect perception and attention. It has been shown that background music can change oculomotor behavior and facilitate detection of visual objects occurring on the musical beat. However, whether musical beats in different tempi modulate information sampling differently during natural viewing remains to be explored. Here we addressed this question by investigating how listening to naturalistic drum grooves in two different tempi affects eye movements of participants viewing natural scenes on a computer screen. We found that the beat frequency of the drum grooves modulated the rate of eye movements: fixation durations were increased at the lower beat frequency (1.7Hz) as compared to the higher beat frequency (2.4Hz) and no music conditions. Correspondingly, estimated visual sampling frequency decreased as fixation durations increased with lower beat frequency. These results imply that slow musical beats can retard sampling of visual information during natural viewing by increasing fixation durations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Two-dimensional analysis of beat wave current drive with intense microwave pulses

    International Nuclear Information System (INIS)

    Amin, M.R.; Cairns, R.A.

    1990-01-01

    Current drive in tokamak plasmas by a beat wave is considered in two-dimensional (2-D) geometry. The beat wave is excited by the non-linear interaction of two intense microwave pulses (free electron lasers) in the plasma. The three-wave non-linear interaction equations in steady state are solved numerically. The 2-D toroidal effect and the effect of finite spatial width of the pump microwave pulses are taken into account for the excitation of the beat mode. To illustrate the principle, two types of tokamak are considered: one is small, such as, typically, the Microwave Tokamak Experiment (MTX). and the other one is larger, such as the Joint European Torus (JET). In both cases, it is found that good beat wave coupling exists for a Langmuir beat wave with a phase velocity of around 2.0 to 4.0 times the thermal velocity of the electrons. The fraction of total input power of the right circularly polarized pump waves deposited in the beat mode can be as high as 29% in JET and 32% in MTX. In these cases, there is almost complete pump depletion of the higher frequency pump microwave. It is also found that, for the same input parameters, left circularly polarized pump waves are less efficient than right circularly polarized pump waves for depositing power in the beat mode. (author). 12 refs, 15 figs, 5 tabs

  7. N-terminal-pro-B-type natriuretic peptide during pharmacological heart rate reduction in hyperthyroidism

    DEFF Research Database (Denmark)

    Schultz, M; Kistorp, C; Corell, P

    2009-01-01

    of pharmacologically induced heart rate reduction in untreated hyperthyroidism. We designed a noncontrolled interventional study. Eighteen women with newly diagnosed hyperthyroidism were evaluated (including an echocardiography) before and after pharmacological heart rate reduction with 360 mg verapamil daily for 6......; resting heart rate [from mean 97 to 80 beats per min (17.5%), p...-index decreased from median 319 to 315 arbitrary units (p=0.039) and free triiodothyronine-index increased from 8.6 to 9.9 arbitrary units (p=0.010). No changes in echocardiographic parameters were observed. A decrease in resting heart rate in untreated hyperthyroidism due to verapamil treatment did not result...

  8. The evolutionary neuroscience of musical beat perception: the Action Simulation for Auditory Prediction (ASAP hypothesis.

    Directory of Open Access Journals (Sweden)

    Aniruddh D. Patel

    2014-05-01

    Full Text Available Every human culture has some form of music with a beat: a perceived periodic pulse that structures the perception of musical rhythm and which serves as a framework for synchronized movement to music. What are the neural mechanisms of musical beat perception, and how did they evolve? One view, which dates back to Darwin and implicitly informs some current models of beat perception, is that the relevant neural mechanisms are relatively general and are widespread among animal species. On the basis of recent neural and cross-species data on musical beat processing, this paper argues for a different view. Here we argue that beat perception is a complex brain function involving temporally-precise communication between auditory regions and motor planning regions of the cortex (even in the absence of overt movement. More specifically, we propose that simulation of periodic movement in motor planning regions provides a neural signal that helps the auditory system predict the timing of upcoming beats. This action simulation for auditory prediction (ASAP hypothesis leads to testable predictions. We further suggest that ASAP relies on dorsal auditory pathway connections between auditory regions and motor planning regions via the parietal cortex, and suggest that these connections may be stronger in humans than in nonhuman primates due to the evolution of vocal learning in our lineage. This suggestion motivates cross-species research to determine which species are capable of human-like beat perception, i.e., beat perception that involves accurate temporal prediction of beat times across a fairly broad range of tempi.

  9. Disentangling beat perception from sequential learning and examining the influence of attention and musical abilities on ERP responses to rhythm.

    Science.gov (United States)

    Bouwer, Fleur L; Werner, Carola M; Knetemann, Myrthe; Honing, Henkjan

    2016-05-01

    Beat perception is the ability to perceive temporal regularity in musical rhythm. When a beat is perceived, predictions about upcoming events can be generated. These predictions can influence processing of subsequent rhythmic events. However, statistical learning of the order of sounds in a sequence can also affect processing of rhythmic events and must be differentiated from beat perception. In the current study, using EEG, we examined the effects of attention and musical abilities on beat perception. To ensure we measured beat perception and not absolute perception of temporal intervals, we used alternating loud and soft tones to create a rhythm with two hierarchical metrical levels. To control for sequential learning of the order of the different sounds, we used temporally regular (isochronous) and jittered rhythmic sequences. The order of sounds was identical in both conditions, but only the regular condition allowed for the perception of a beat. Unexpected intensity decrements were introduced on the beat and offbeat. In the regular condition, both beat perception and sequential learning were expected to enhance detection of these deviants on the beat. In the jittered condition, only sequential learning was expected to affect processing of the deviants. ERP responses to deviants were larger on the beat than offbeat in both conditions. Importantly, this difference was larger in the regular condition than in the jittered condition, suggesting that beat perception influenced responses to rhythmic events in addition to sequential learning. The influence of beat perception was present both with and without attention directed at the rhythm. Moreover, beat perception as measured with ERPs correlated with musical abilities, but only when attention was directed at the stimuli. Our study shows that beat perception is possible when attention is not directed at a rhythm. In addition, our results suggest that attention may mediate the influence of musical abilities on beat

  10. Three-dimensional surface reconstruction imaging for evaluation of congenital heart disease from ECG-triggered MR images

    International Nuclear Information System (INIS)

    Vannier, M.W.; Laschinger, J.; Knapp, R.H.; Gutierrez, F.R.; Gronnemeyer, S.A.

    1987-01-01

    Three-dimensional surface reconstruction images of the heart and great vessels were produced from contiguous sequences of electrocardiographically triggered MR images in 25 patients with congenital heart disease and in three healthy subjects. The imaging data were semiautomatically processed to separate the epicardial and endocardial surfaces and to define the outline of the enclosed blood volumes on a section by section basis. Images were obtained at 5-mm intervals in patients aged 3 months to 30 years with anomalies of the great vessels, tetralogy of Fallot, septal defects, pulmonary atresia, and other congenital heart malformations. The results were used to facilitate the surgical treatment of these patients and were compared with echocardiographic and cineradiographic studies, and with surgical findings or pathologic specimens. These surface reconstruction images were useful for communicating the results of diagnostic examinations to cardiac surgeons, for sizing and location of intracardiac defects, for imaging the pulmonary venous drainage, and for assessing regional and global function

  11. Quantum beat and entanglement of multi-qubits interacting with a common reservoir

    International Nuclear Information System (INIS)

    Sato, Arata; Ishi-Hayase, Junko; Minami, Fujio; Sasaki, Masahide

    2006-01-01

    The qubits can be entangled when they interact with a common Ohmic reservoir. We analyze how the reservoir-induced entanglement of qubits can be observed as the beat signal in the decay curve of the macroscopic polarization. The origin of this effect is the Lamb phase shift on the qubit array. We quantify the amount of the reservoir-induced entanglement and show how to experimentally evaluate it from the decay curve of the macroscopic polarization. We discuss how the beat signal can be discriminated from the other kinds of beat signals. We also show that our analysis can be used to estimate the reservoir characteristics

  12. Dysfunction of Right Heart in Attack Period of Bronchial Asthma in Children

    Directory of Open Access Journals (Sweden)

    V.А. Kondratiev

    2015-11-01

    Full Text Available There were performed Doppler echocardiography investigations of functional state of the right heart in 42 children aged 5–17 years old in attack period of bronchial asthma of moderate to severe degree. Changes of intra-cardiac hemodynamics of the right heart in children in attack period of bronchial asthma were characterized by disturbance of systolic and diastolic function of the right ventricle and right atrium. Combined systolic-diastolic variant of the right ventricle dysfunction was typical for attack period of bronchial asthma in children and developed in 95.5 % of cases. Elevation of pressure in pulmonary artery was typical and significantly more often occurred in severe asthma attack, herewith pulmonary hypertension of the second degree predominated.

  13. The effect of competition on heart rate during kart driving: A field study

    Science.gov (United States)

    2011-01-01

    Background Both the act of competing, which can create a kind of mental stress, and participation in motor sports, which induces physical stress from intense g-forces, are known to increase heart rate dramatically. However, little is known about the specific effect of competition on heart rate during motor sports, particularly during four-wheel car driving. The goal of this preliminary study, therefore, was to investigate whether competition increases heart rate under such situations. Findings The participants drove an entry-level formula kart during two competitive races and during solo driving against the clock while heart rate and g-forces were measured. Analyses showed that heart rate values during the races (168.8 beats/min) were significantly higher than those during solo driving (140.9 beats/min) and rest (75.1 beats/min). Conclusions The results of this preliminary study indicate that competition heightens heart rate during four-wheel car driving. Kart drivers should be concerned about maintaining good health and developing physical strength. PMID:21906298

  14. Intracardiac Metastatic Rhabdomyosarcoma

    Directory of Open Access Journals (Sweden)

    Tae Ho Kim

    2015-12-01

    Full Text Available A 70-year-old man who visited Samsung Medical Center reported experiencing palpitation for 2 weeks. He had undergone excision of a mass in the right buttock due to rhabdomyosarcoma 7 years prior to this visit. Transesophageal echocardiography showed a pedunculated mass in the left ventricle, which was thought to be a vegetation of infective endocarditis, metastasis of the primary tumor, or thrombus. He underwent removal of the cardiac tumor, and the pathologic report was metastatic rhabdomyosarcoma. Thus, here, we report a rare case of metastatic rhabdomyosarcoma in the left ventricle.

  15. INTRACARDIAC ATRIAL DEFIBRILLATION

    Science.gov (United States)

    Dosdall, Derek J.; Ideker, Raymond E.

    2007-01-01

    Intravascular ventricular defibrillation and intravascular atrial defibrillation have many similarities, some of which are as follows. An important factor influencing the outcome of the shock is the potential gradient field created throughout the ventricles or the atria by the shock. A minimum potential gradient is required throughout the ventricles and probably the atria to defibrillate. The value of this minimum potential gradient is affected by several factors including the duration, tilt, and number of phases of the waveform. For shock strengths near the defibrillation threshold, earliest activation following failed shocks arises in a region in which the potential gradient is low. The defibrillation threshold energy can be decreased by adding a third and even a fourth defibrillation electrode in regions where the shock potential gradient is low for the shock field created by the first two defibrillation electrodes and giving two sequential shocks, each through a different set of electrodes. However, the addition of more electrodes and sequential shocks complicates both the device and its implantation. Since patients are conscious when the atrial defibrillation shock is given, they experience pain during the shock, which is one of the main drawbacks of intravascular atrial defibrillation. Unfortunately, the pain threshold for defibrillation shocks is so low that a shock of less than 1 Joule is uncomfortable and is not much less painful than shocks several times stronger. Therefore, even though electrode configurations exist that have lower atrial defibrillation threshold energy requirements than the atrial defibrillation threshold with standard defibrillation electrode configurations used in implantable cardioverter/defibrillators (ICDs) for ventricular defibrillation, they are not clinically practical because their shocks are almost as painful as with the standard ICD electrode configurations and they would cause the ICD to be more complicated and to take longer and be more difficult to implant. PMID:17336885

  16. Investigation of the interaction of radiation and cardiotoxic anticancer agents using a fetal mouse heart organ culture system

    International Nuclear Information System (INIS)

    Kimler, B.F.; Rethorst, R.D.; Cox, G.G.

    1985-01-01

    The fetal mouse heart organ culture was utilized in an attempt to predict the cardiotoxic effects of combinations of radiation, Adriamycin (ADR), and Dihydroxyanthraquinone (DHAQ), antineoplastic agents which have been shown to produce clinical cardiomyopathy. Seventeen-day fetal hearts were removed and placed in a culture system of micro-titer plates. A single heart was placed in each well on a piece of aluminum mesh to keep the heart above the culture medium but bathed by capillary action. The plates were then placed in a 100% oxygen environment at 37 0 C. Treatments were performed on day 1 after culture: radiation doses (Cs-137) of 10, 20, or 40 Gy; drug treatment with 10, 30, or 100 μg/ml of ADR; 5, 20, or 50 μg/ml of DHAQ; and combinations and sequences of drug and radiation. Hearts were checked every day for functional activity as evidenced by a continuous heart beat. Untreated hearts beat rhythmically for up to 9 days; treated hearts stopped beating earlier. Using an endpoint of functional retention time, dose response curves were obtained for all individual agents and for combinations of agents. This system may help to predict the cardiotoxic effects that result from the use of these drugs and radiation. It may also aid in the development of new anthracycline chemotherapeutic agents that lack cardiotoxicity

  17. Heart transplant

    Science.gov (United States)

    ... hospital for 7 to 21 days after a heart transplant. The first 24 to 48 hours will likely be in ... follow your self-care instructions. Biopsies of the heart muscle are ... after transplant, and then less often after that. This helps ...

  18. Application of binaural beat phenomenon with aphasic patients.

    Science.gov (United States)

    Barr, D F; Mullin, T A; Herbert, P S

    1977-04-01

    We investigated whether six aphasics and six normal subjects could binaurally fuse two slightly differing frequencies of constant amplitude. The aphasics were subdivided into two groups: (1) two men who had had mild cerebrovascular accidents (CVAs) during the past 15 months; (2) four men who had had severe CVAs during the last 15 months. Two tones of different frequency levels but equal in intensity were presented dichotically to the subjects at 40 dB sensation level. All subjects had normal hearing at 500 Hz (0 to 25 dB). All six normal subjects and the two aphasics who had had mild CVAs could hear the binaural beats. The four aphasics who had had severe CVAs could not hear them. A 2 X 2 design resulting from this study was compared using chi2 test with Yates correction and was found to be significantly different (P less than .05). Two theories are presented to explain these findings: the "depression theory" and the "temporal time-sequencing theory." Therapeutic implications are also discussed relative to cerebral and/or brain stem involvement in the fusion of binaural stimuli.

  19. A question of getting the right BEAT? Life cycle assesment

    Energy Technology Data Exchange (ETDEWEB)

    Zeiler, W. [Kropman Building Services, Nijmegen (Netherlands); Van Deursen, J.T.; Boxem, G. [Technische Universiteit Eindhoven, Eindhoven (Netherlands)

    2009-06-15

    There is a strong need for more efficient and more sustainable buildings. At present it is difficult in the conceptual design phase to define the life cycle performance of buildings in terms of efficiency and sustainability in an objective way. Goal of this project is to examine and to understand differences between different building rating systems and between these systems and the necessary design support. What makes a good building is subject to multiple interpretations based on the different background, training and experiences of the people who answer the question about how good a building is. What is needed is a new integral design approach which enables to integrate the different aspects of sustainable buildings in a supportive framework during the design process. Especially, the focus is on Multi Criteria Decision making within the design process and how to support this, so that the decisions about fulfilling sustainable aspects in the design are made transparent for all stakeholders within the design process. BEAT in the title stands for Building Environmental Assessment Tools.

  20. Coordinated beating of algal flagella is mediated by basal coupling

    Science.gov (United States)

    Wan, Kirsty Y.; Goldstein, Raymond E.

    2016-01-01

    Cilia and flagella often exhibit synchronized behavior; this includes phase locking, as seen in Chlamydomonas, and metachronal wave formation in the respiratory cilia of higher organisms. Since the observations by Gray and Rothschild of phase synchrony of nearby swimming spermatozoa, it has been a working hypothesis that synchrony arises from hydrodynamic interactions between beating filaments. Recent work on the dynamics of physically separated pairs of flagella isolated from the multicellular alga Volvox has shown that hydrodynamic coupling alone is sufficient to produce synchrony. However, the situation is more complex in unicellular organisms bearing few flagella. We show that flagella of Chlamydomonas mutants deficient in filamentary connections between basal bodies display markedly different synchronization from the wild type. We perform micromanipulation on configurations of flagella and conclude that a mechanism, internal to the cell, must provide an additional flagellar coupling. In naturally occurring species with 4, 8, or even 16 flagella, we find diverse symmetries of basal body positioning and of the flagellar apparatus that are coincident with specific gaits of flagellar actuation, suggesting that it is a competition between intracellular coupling and hydrodynamic interactions that ultimately determines the precise form of flagellar coordination in unicellular algae. PMID:27140605

  1. Electromyographic activity of beating and reaching during simulated boardsailing.

    Science.gov (United States)

    Buchanan, M; Cunningham, P; Dyson, R J; Hurrion, P D

    1996-04-01

    This study examined the responses of six competitive boardsailors (three males, three females) during laboratory-based simulation tasks while the electromyographic activity of up to 13 muscles was recorded. A sailboard, mounted in a steel frame and resting on a waterbed, allowed simulation of roll and pitch movements. Wind force was simulated by attaching the boom to a weight stack with a hydraulically controlled buffered release phase. The progression of the simulation test was controlled by the sailor copying movements on an edited video of each subject boardsailing on the open water. Analysis of individual pumping movements for mean peak percentage of maximal enveloped voluntary contraction (%MEVC) in 'beating' and 'reaching' showed that muscular activity in the arm (flexor carpi ulnaris, extensor carpi radialis and biceps brachii) was greatest (66-94% MEVC), with considerable activity (58-75% MEVC) in the deltoid and trapezius shoulder muscles, but much less activity in the leg muscles (16-40% MEVC). For the combined upper and lower body muscles there was a significant difference (P reflecting the current dynamic nature of the sport.

  2. [Autonomic angiotensinergic fibres in the human heart with an efferent sympathetic cophenotype].

    Science.gov (United States)

    Bohlender, J; Nussberger, J; Tevaearai, H; Imboden, H

    2015-06-01

    The autonomic innervation of the heart consists of sympathetic and parasympathetic nerve fibres, and fibres of the intrinsic ganglionated plexus with noradrenaline and acytylcholine as principal neurotransmitters. The fibres co-release neuropeptides to modulate intracardiac neurotransmission by specific presynaptic and postsynaptic receptors. The coexpression of angiotensin II in sympathetic fibres of the human heart and its role are not known so far. Autopsy specimens of human hearts were studied (n=3; ventricles). Using immunocytological methods, cryostat sections were stained by a murine monoclonal antibody (4B3) directed against angiotensin II and co-stained by polyclonal antibodies against tyrosine hydroxylase, a catecholaminergic marker. Visualisation of the antibodies was by confocal light microscopy or laser scanning microscopy. Angiotensin II-positive autonomic fibres with and without a catecholaminergic cophenotype (hydroxylase-positive) were found in all parts of the human ventricles. In the epicardium, the fibres were grouped in larger bundles of up to 100 and more fibres. They followed the preformed anatomic septa and epicardial vessels towards the myocardium and endocardium where the bundles dissolved and the individual fibres spread between myocytes and within the endocardium. Generally, angiotensinergic fibres showed no synaptic enlargements or only a few if they were also catecholaminergic. The exclusively catechalominergic fibres were characterised by multiple beaded synapses. The autonomic innervation of the human heart contains angiotensinergic fibres with a sympathetic efferent phenotype and exclusively angiotensinergic fibers representing probably afferents. Angiotensinergic neurotransmission may modulate intracardiac sympathetic and parasympathetic activity and thereby influence cardiac and circulatory function. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  3. The power of auditory-motor synchronization in sports: enhancing running performance by coupling cadence with the right beats.

    Science.gov (United States)

    Bood, Robert Jan; Nijssen, Marijn; van der Kamp, John; Roerdink, Melvyn

    2013-01-01

    Acoustic stimuli, like music and metronomes, are often used in sports. Adjusting movement tempo to acoustic stimuli (i.e., auditory-motor synchronization) may be beneficial for sports performance. However, music also possesses motivational qualities that may further enhance performance. Our objective was to examine the relative effects of auditory-motor synchronization and the motivational impact of acoustic stimuli on running performance. To this end, 19 participants ran to exhaustion on a treadmill in 1) a control condition without acoustic stimuli, 2) a metronome condition with a sequence of beeps matching participants' cadence (synchronization), and 3) a music condition with synchronous motivational music matched to participants' cadence (synchronization+motivation). Conditions were counterbalanced and measurements were taken on separate days. As expected, time to exhaustion was significantly longer with acoustic stimuli than without. Unexpectedly, however, time to exhaustion did not differ between metronome and motivational music conditions, despite differences in motivational quality. Motivational music slightly reduced perceived exertion of sub-maximal running intensity and heart rates of (near-)maximal running intensity. The beat of the stimuli -which was most salient during the metronome condition- helped runners to maintain a consistent pace by coupling cadence to the prescribed tempo. Thus, acoustic stimuli may have enhanced running performance because runners worked harder as a result of motivational aspects (most pronounced with motivational music) and more efficiently as a result of auditory-motor synchronization (most notable with metronome beeps). These findings imply that running to motivational music with a very prominent and consistent beat matched to the runner's cadence will likely yield optimal effects because it helps to elevate physiological effort at a high perceived exertion, whereas the consistent and correct cadence induced by auditory

  4. The power of auditory-motor synchronization in sports: enhancing running performance by coupling cadence with the right beats.

    Directory of Open Access Journals (Sweden)

    Robert Jan Bood

    Full Text Available Acoustic stimuli, like music and metronomes, are often used in sports. Adjusting movement tempo to acoustic stimuli (i.e., auditory-motor synchronization may be beneficial for sports performance. However, music also possesses motivational qualities that may further enhance performance. Our objective was to examine the relative effects of auditory-motor synchronization and the motivational impact of acoustic stimuli on running performance. To this end, 19 participants ran to exhaustion on a treadmill in 1 a control condition without acoustic stimuli, 2 a metronome condition with a sequence of beeps matching participants' cadence (synchronization, and 3 a music condition with synchronous motivational music matched to participants' cadence (synchronization+motivation. Conditions were counterbalanced and measurements were taken on separate days. As expected, time to exhaustion was significantly longer with acoustic stimuli than without. Unexpectedly, however, time to exhaustion did not differ between metronome and motivational music conditions, despite differences in motivational quality. Motivational music slightly reduced perceived exertion of sub-maximal running intensity and heart rates of (near-maximal running intensity. The beat of the stimuli -which was most salient during the metronome condition- helped runners to maintain a consistent pace by coupling cadence to the prescribed tempo. Thus, acoustic stimuli may have enhanced running performance because runners worked harder as a result of motivational aspects (most pronounced with motivational music and more efficiently as a result of auditory-motor synchronization (most notable with metronome beeps. These findings imply that running to motivational music with a very prominent and consistent beat matched to the runner's cadence will likely yield optimal effects because it helps to elevate physiological effort at a high perceived exertion, whereas the consistent and correct cadence induced by

  5. The Power of Auditory-Motor Synchronization in Sports: Enhancing Running Performance by Coupling Cadence with the Right Beats

    Science.gov (United States)

    Bood, Robert Jan; Nijssen, Marijn; van der Kamp, John; Roerdink, Melvyn

    2013-01-01

    Acoustic stimuli, like music and metronomes, are often used in sports. Adjusting movement tempo to acoustic stimuli (i.e., auditory-motor synchronization) may be beneficial for sports performance. However, music also possesses motivational qualities that may further enhance performance. Our objective was to examine the relative effects of auditory-motor synchronization and the motivational impact of acoustic stimuli on running performance. To this end, 19 participants ran to exhaustion on a treadmill in 1) a control condition without acoustic stimuli, 2) a metronome condition with a sequence of beeps matching participants’ cadence (synchronization), and 3) a music condition with synchronous motivational music matched to participants’ cadence (synchronization+motivation). Conditions were counterbalanced and measurements were taken on separate days. As expected, time to exhaustion was significantly longer with acoustic stimuli than without. Unexpectedly, however, time to exhaustion did not differ between metronome and motivational music conditions, despite differences in motivational quality. Motivational music slightly reduced perceived exertion of sub-maximal running intensity and heart rates of (near-)maximal running intensity. The beat of the stimuli –which was most salient during the metronome condition– helped runners to maintain a consistent pace by coupling cadence to the prescribed tempo. Thus, acoustic stimuli may have enhanced running performance because runners worked harder as a result of motivational aspects (most pronounced with motivational music) and more efficiently as a result of auditory-motor synchronization (most notable with metronome beeps). These findings imply that running to motivational music with a very prominent and consistent beat matched to the runner’s cadence will likely yield optimal effects because it helps to elevate physiological effort at a high perceived exertion, whereas the consistent and correct cadence induced by

  6. Short-term beat-to-beat variability of the QT interval is increased and correlates with parameters of left ventricular hypertrophy in patients with hypertrophic cardiomyopathy.

    Science.gov (United States)

    Orosz, Andrea; Baczkó, István; Nagy, Viktória; Gavallér, Henriette; Csanády, Miklós; Forster, Tamás; Papp, Julius Gy; Varró, András; Lengyel, Csaba; Sepp, Róbert

    2015-09-01

    Stratification models for the prediction of sudden cardiac death (SCD) are inappropriate in patients with hypertrophic cardiomyopathy (HCM). We investigated conventional electrocardiogram (ECG) repolarization parameters and the beat-to-beat short-term QT interval variability (QT-STV), a new parameter of proarrhythmic risk, in 37 patients with HCM (21 males, average age 48 ± 15 years). Resting ECGs were recorded for 5 min and the frequency corrected QT interval (QTc), QT dispersion (QTd), beat-to-beat short-term variability of QT interval (QT-STV), and the duration of terminal part of T waves (Tpeak-Tend) were calculated. While all repolarization parameters were significantly increased in patients with HCM compared with the controls (QTc, 488 ± 61 vs. 434 ± 23 ms, p < 0.0001; QT-STV, 4.5 ± 2 vs. 3.2 ± 1 ms, p = 0.0002; Tpeak-Tend duration, 107 ± 27 vs. 91 ± 10 ms, p = 0.0015; QTd, 47 ± 17 vs. 34 ± 9 ms, p = 0.0002), QT-STV had the highest relative increase (+41%). QT-STV also showed the best correlation with indices of left ventricular (LV) hypertrophy, i.e., maximal LV wall thickness normalized for body surface area (BSA; r = 0.461, p = 0.004) or LV mass (determined by cardiac magnetic resonance imaging) normalized for BSA (r = 0.455, p = 0.015). In summary, beat-to-beat QT-STV showed the most marked increase in patients with HCM and may represent a novel marker that merits further testing for increased SCD risk in HCM.

  7. Resting heart rate, heart rate variability and functional decline in old age.

    Science.gov (United States)

    Ogliari, Giulia; Mahinrad, Simin; Stott, David J; Jukema, J Wouter; Mooijaart, Simon P; Macfarlane, Peter W; Clark, Elaine N; Kearney, Patricia M; Westendorp, Rudi G J; de Craen, Anton J M; Sabayan, Behnam

    2015-10-20

    Heart rate and heart rate variability, markers of cardiac autonomic function, have been linked with cardiovascular disease. We investigated whether heart rate and heart rate variability are associated with functional status in older adults, independent of cardiovascular disease. We obtained data from the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER). A total of 5042 participants were included in the present study, and mean follow-up was 3.2 years. Heart rate and heart rate variability were derived from baseline 10-second electrocardiograms. Heart rate variability was defined as the standard deviation of normal-to-normal RR intervals (SDNN). Functional status in basic (ADL) and instrumental (IADL) activities of daily living was measured using Barthel and Lawton scales, at baseline and during follow-up. The mean age of the study population was 75.3 years. At baseline, higher heart rate was associated with worse ADL and IADL, and lower SDNN was related to worse IADL (all p values heart rate (range 71-117 beats/min) had a 1.79-fold (95% confidence interval [CI] 1.45-2.22) and 1.35-fold (95% CI 1.12-1.63) higher risk of decline in ADL and IADL, respectively (p for trend heart rate and lower heart rate variability were associated with worse functional status and with higher risk of future functional decline in older adults, independent of cardiovascular disease. This study provides insight into the role of cardiac autonomic function in the development of functional decline. © 2015 Canadian Medical Association or its licensors.

  8. Application of a "relative" procedure to a problem in binaural beat perception.

    Science.gov (United States)

    1963-08-01

    The existence of binaural beats has long been considered an indication of binaural interaction for timing and for periodicity of information. In the past, bilaterally matched sound pressure or sensation levels have been used in the investigation of t...

  9. The Effect of Dopaminergic Medication on Beat-Based Auditory Timing in Parkinson's Disease

    Directory of Open Access Journals (Sweden)

    Daniel J Cameron

    2016-02-01

    Full Text Available Parkinson’s disease (PD adversely affects timing abilities. Beat-based timing is a mechanism that times events relative to a regular interval, such as the ‘beat’ in musical rhythm, and is impaired in PD. It is unknown if dopaminergic medication influences beat-based timing in PD. Here we tested beat-based timing over two sessions in participants with PD (OFF then ON dopaminergic medication, and unmedicated control participants. People with PD and control participants completed two tasks. The first was a discrimination task in which participants compared two rhythms and determined whether they were the same or different. Rhythms either had a beat structure (metric simple rhythms, or did not (metric complex rhythms, as in previous studies. Discrimination accuracy was analyzed to test for the effects of beat structure, as well as differences between participants with PD and controls, and effects of medication (PD group only. The second task was the Beat Alignment Test (BAT, in which participants listened to music with regular tones superimposed, and responded as to whether the tones were ‘on’ or ‘off’ the beat of the music. Accuracy was analyzed to test for differences between participants with PD and controls, and for an effect of medication in patients.Both patients and controls discriminated metric simple rhythms better than metric complex rhythms. Controls also improved at the discrimination task in the second vs. first session, whereas people with PD did not. For participants with PD, the difference in performance between metric simple and metric complex rhythms was greater (sensitivity to changes in simple rhythms increased and sensitivity to changes in complex rhythms decreased when ON vs. OFF medication. Performance also worsened with disease severity. For the Beat Alignment Test, no group differences or effects of medication were found. Overall, these findings suggest that timing is impaired in PD, and that dopaminergic

  10. Binaural beat technology in humans: a pilot study to assess neuropsychologic, physiologic, and electroencephalographic effects.

    Science.gov (United States)

    Wahbeh, Helané; Calabrese, Carlo; Zwickey, Heather; Zajdel, Dan

    2007-03-01

    When two auditory stimuli of different frequency are presented to each ear, binaural beats are perceived by the listener. The binaural beat frequency is equal to the difference between the frequencies applied to each ear. Our primary objective was to assess whether steady-state entrainment of electroencephalographic activity to the binaural beat occurs when exposed to a specific binaural beat frequency as has been hypothesized. Our secondary objective was to gather preliminary data on neuropsychologic and physiologic effects of binaural beat technology. A randomized, blinded, placebo-controlled crossover experiment in 4 healthy adult subjects. Subjects were randomized to experimental auditory stimulus of 30 minutes of binaural beat at 7 Hz (carrier frequencies: 133 Hz L; 140 Hz R) with an overlay of pink noise resembling the sound of rain on one session and control stimuli of the same overlay without the binaural beat carrier frequencies on the other session. Data were collected during two separate sessions 1 week apart. Neuropsychologic and blood pressure data were collected before and after the intervention; electroencephalographic data were collected before, during, and after listening to either binaural beats or control. Neuropsychologic measures included State Trait Anxiety Inventory, Profile of Mood States, Rey Auditory Verbal List Test, Stroop Test, and Controlled Oral Word Association Test. Spectral and coherence analysis was performed on the electroencephalogram (EEG), and all measures were analyzed for changes between sessions with and without binaural beat stimuli. There were no significant differences between the experimental and control conditions in any of the EEG measures. There was an increase of the Profile of Mood States depression subscale in the experimental condition relative to the control condition (p = 0.02). There was also a significant decrease in immediate verbal memory recall (p = 0.03) in the experimental condition compared to control

  11. The effect of gamma-enhancing binaural beats on the control of feature bindings

    OpenAIRE

    Colzato, L.S.; Steenbergen, L.; Sellaro, R.

    2017-01-01

    Binaural beats represent the auditory experience of an oscillating sound that occurs when two sounds with neighboring frequencies are presented to one?s left and right ear separately. Binaural beats have been shown to impact information processing via their putative role in increasing neural synchronization. Recent studies of feature-repetition effects demonstrated interactions between perceptual features and action-related features: repeating only some, but not all features of a perception?a...

  12. Mismatch negativity to acoustical illusion of beat: how and where the change detection takes place?

    Science.gov (United States)

    Chakalov, Ivan; Paraskevopoulos, Evangelos; Wollbrink, Andreas; Pantev, Christo

    2014-10-15

    In case of binaural presentation of two tones with slightly different frequencies the structures of brainstem can no longer follow the interaural time differences (ITD) resulting in an illusionary perception of beat corresponding to frequency difference between the two prime tones. Hence, the beat-frequency does not exist in the prime tones presented to either ear. This study used binaural beats to explore the nature of acoustic deviance detection in humans by means of magnetoencephalography (MEG). Recent research suggests that the auditory change detection is a multistage process. To test this, we employed 26 Hz-binaural beats in a classical oddball paradigm. However, the prime tones (250 Hz and 276 Hz) were switched between the ears in the case of the deviant-beat. Consequently, when the deviant is presented, the cochleae and auditory nerves receive a "new afferent", although the standards and the deviants are heard identical (26 Hz-beats). This allowed us to explore the contribution of auditory periphery to change detection process, and furthermore, to evaluate its influence on beats-related auditory steady-state responses (ASSRs). LORETA-source current density estimates of the evoked fields in a typical mismatch negativity time-window (MMN) and the subsequent difference-ASSRs were determined and compared. The results revealed an MMN generated by a complex neural network including the right parietal lobe and the left middle frontal gyrus. Furthermore, difference-ASSR was generated in the paracentral gyrus. Additionally, psychophysical measures showed no perceptual difference between the standard- and deviant-beats when isolated by noise. These results suggest that the auditory periphery has an important contribution to novelty detection already at sub-cortical level. Overall, the present findings support the notion of hierarchically organized acoustic novelty detection system. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. More attentional focusing through binaural beats: Evidence from the global-local task

    OpenAIRE

    Colzato, L.S.; Barone, H.; Sellaro, R.; Hommel, B.

    2017-01-01

    A recent study showed that binaural beats have an impact on the efficiency of allocating attention over time. We were interested to see whether this impact affects attentional focusing or, even further, the top-down control over irrelevant information. Healthy adults listened to gamma-frequency (40?Hz) binaural beats, which are assumed to increase attentional concentration, or a constant tone of 340?Hz (control condition) for 3?min before and during a global?local task. While the size of the ...

  14. Extraction of cilium beat parameters by the combined application of photoelectric measurements and computer simulation.

    OpenAIRE

    Gheber, L; Priel, Z

    1997-01-01

    Photoelectric signals were created and used to investigate the features of the signals as a function of the ciliary beat parameters. Moreover, correlation between the simulated and the measured signals permitted measurement of the cilium beat parameters. The simulations of the signals were based on generation of a series of time-frozen top-view frames of an active ciliary area and determination of the amount of light passing through an observation area in each of these frames. All the factors...

  15. Beat wave current drive with intense pulsed free-electron lasers

    International Nuclear Information System (INIS)

    Cohen, B.I.; Cohen, R.H.; Logan, B.G.; McCay Nevins, W.; Smith, G.R.; Kluge, A.V.; Kritz, A.H.

    1988-01-01

    High power free-electron lasers make possible new methods for driving current in toroidal devices with electromagnetic waves. Earlier considerations of beat wave current drive are applied to a hot magnetized plasma and an arbitrary beat wave. Here the beating of two electromagnetic waves resonantly excites a low frequency beat wave that accelerates and heats electrons and leads to a current. The absolute current drive efficiency depends non-linearly on the two pump wave intensities and is constrained by the Manley-Rowe relations. Accessibility at high plasma densities is not a difficulty, but a degree of frequency tunability of the wave sources is required. Particle simulations indicate that there is a good coupling to an electron velocity tail for a Langmuir beat wave with a phase velocity 1.5 to 3 times (T e /m e ) 1/2 , so that all of the high frequency wave source is absorbed and the beat wave damps completely on the electrons. A novel diagnostic, based on an analytical solution for the linearized Fokker-Planck equation describing electron scattering and slowing down, is added to the particle code. This permits the computation of the current drive efficiency, including both the non-linear beat wave coupling and the collisional relaxation of the electron distribution. A realistic scenario for a beat wave current drive experiment in the Livermore Microwave Tokamak Experiment is calculated using the TORAY toroidal ray tracing code, and the scaling to an engineering test reactor plasma is described. (author). 23 refs, 8 figs

  16. Autonomic control of heart rate after exercise in trained wrestlers.

    Science.gov (United States)

    Henríquez, Olguín C; Báez, San Martín E; Von Oetinger, A; Cañas, Jamett R; Ramírez, Campillo R

    2013-06-01

    The objective of this study was to establish differences in vagal reactivation, through heart rate recovery and heart rate variability post exercise, in Brazilian jiu-jitsu wrestlers (BJJW). A total of 18 male athletes were evaluated, ten highly trained (HT) and eight moderately trained (MT), who performed a maximum incremental test. At the end of the exercise, the R-R intervals were recorded during the first minute of recovery. We calculated heart rate recovery (HRR60s), and performed linear and non-linear (standard deviation of instantaneous beat-to-beat R-R interval variability - SD1) analysis of heart rate variability (HRV), using the tachogram of the first minute of recovery divided into four segments of 15 s each (0-15 s, 15-30 s, 30-45 s, 45-60 s). Between HT and MT individuals, there were statistically significant differences in HRR60s (p <0.05) and in the non linear analysis of HRV from SD130-45s (p <0.05) and SD145-60s (p <0.05). The results of this research suggest that heart rate kinetics during the first minute after exercise are related to training level and can be used as an index for autonomic cardiovascular control in BJJW.

  17. AUTONOMIC CONTROL OF HEART RATE AFTER EXERCISE IN TRAINED WRESTLERS

    Directory of Open Access Journals (Sweden)

    Carlos F Henríquez

    2013-04-01

    Full Text Available The objective of this study was to establish differences in vagal reactivation, through heart rate recovery and heart rate variability post exercise, in Brazilian jiu-jitsu wrestlers (BJJW. A total of 18 male athletes were evaluated, ten highly trained (HT and eight moderately trained (MT, who performed a maximum incremental test. At the end of the exercise, the R-R intervals were recorded during the first minute of recovery. We calculated heart rate recovery (HRR60s, and performed linear and non-linear (standard deviation of instantaneous beat-to-beat R-R interval variability – SD1 analysis of heart rate variability (HRV, using the tachogram of the first minute of recovery divided into four segments of 15 s each (0-15 s, 15-30 s, 30-45 s, 45-60 s. Between HT and MT individuals, there were statistically significant differences in HRR60s (p <0.05 and in the non linear analysis of HRV from SD130-45s (p <0.05 and SD145-60s (p <0.05. The results of this research suggest that heart rate kinetics during the first minute after exercise are related to training level and can be used as an index for autonomic cardiovascular control in BJJW.

  18. Mouse heart rate in a human: diagnostic mystery of an extreme tachyarrhythmia.

    Science.gov (United States)

    Chhabra, Lovely; Goel, Narender; Prajapat, Laxman; Spodick, David H; Goyal, Sanjeev

    2012-01-01

    We report telemetry recording of an extreme non-fatal tachyarrhythmia noted in a hospitalized quadriplegic male with history of atrial fibrillation where the average ventricular conduction rate was found to be about 600 beats per minute and was associated with transient syncope. A medical literature review suggests that the fastest human ventricular conduction rate reported to date in a tachyarrhythmia is 480 beats per minute. We therefore report the fastest human heart rate noted in a tachyarrhythmia and the most probable mechanism of this arrhythmia being a rapid atrial fibrillation with 1:1 conduction in the setting of probable co-existing multiple bypass tracts.

  19. The effects of auditory stimulation with music on heart rate variability in healthy women.

    Science.gov (United States)

    Roque, Adriano L; Valenti, Vitor E; Guida, Heraldo L; Campos, Mônica F; Knap, André; Vanderlei, Luiz Carlos M; Ferreira, Lucas L; Ferreira, Celso; Abreu, Luiz Carlos de

    2013-07-01

    There are no data in the literature with regard to the acute effects of different styles of music on the geometric indices of heart rate variability. In this study, we evaluated the acute effects of relaxant baroque and excitatory heavy metal music on the geometric indices of heart rate variability in women. We conducted this study in 21 healthy women ranging in age from 18 to 35 years. We excluded persons with previous experience with musical instruments and persons who had an affinity for the song styles. We evaluated two groups: Group 1 (n = 21), who were exposed to relaxant classical baroque musical and excitatory heavy metal auditory stimulation; and Group 2 (n = 19), who were exposed to both styles of music and white noise auditory stimulation. Using earphones, the volunteers were exposed to baroque or heavy metal music for five minutes. After the first music exposure to baroque or heavy metal music, they remained at rest for five minutes; subsequently, they were re-exposed to the opposite music (70-80 dB). A different group of women were exposed to the same music styles plus white noise auditory stimulation (90 dB). The sequence of the songs was randomized for each individual. We analyzed the following indices: triangular index, triangular interpolation of RR intervals and Poincaré plot (standard deviation of instantaneous beat-by-beat variability, standard deviation of the long-term RR interval, standard deviation of instantaneous beat-by-beat variability and standard deviation of the long-term RR interval ratio), low frequency, high frequency, low frequency/high frequency ratio, standard deviation of all the normal RR intervals, root-mean square of differences between the adjacent normal RR intervals and the percentage of adjacent RR intervals with a difference of duration greater than 50 ms. Heart rate variability was recorded at rest for 10 minutes. The triangular index and the standard deviation of the long-term RR interval indices were reduced

  20. The effects of auditory stimulation with music on heart rate variability in healthy women

    Directory of Open Access Journals (Sweden)

    Adriano L. Roque

    2013-07-01

    Full Text Available OBJECTIVES: There are no data in the literature with regard to the acute effects of different styles of music on the geometric indices of heart rate variability. In this study, we evaluated the acute effects of relaxant baroque and excitatory heavy metal music on the geometric indices of heart rate variability in women. METHODS: We conducted this study in 21 healthy women ranging in age from 18 to 35 years. We excluded persons with previous experience with musical instruments and persons who had an affinity for the song styles. We evaluated two groups: Group 1 (n = 21, who were exposed to relaxant classical baroque musical and excitatory heavy metal auditory stimulation; and Group 2 (n = 19, who were exposed to both styles of music and white noise auditory stimulation. Using earphones, the volunteers were exposed to baroque or heavy metal music for five minutes. After the first music exposure to baroque or heavy metal music, they remained at rest for five minutes; subsequently, they were re-exposed to the opposite music (70-80 dB. A different group of women were exposed to the same music styles plus white noise auditory stimulation (90 dB. The sequence of the songs was randomized for each individual. We analyzed the following indices: triangular index, triangular interpolation of RR intervals and Poincaré plot (standard deviation of instantaneous beat-by-beat variability, standard deviation of the long-term RR interval, standard deviation of instantaneous beat-by-beat variability and standard deviation of the long-term RR interval ratio, low frequency, high frequency, low frequency/high frequency ratio, standard deviation of all the normal RR intervals, root-mean square of differences between the adjacent normal RR intervals and the percentage of adjacent RR intervals with a difference of duration greater than 50 ms. Heart rate variability was recorded at rest for 10 minutes. RESULTS: The triangular index and the standard deviation of

  1. A high-density EEG investigation into steady state binaural beat stimulation.

    Directory of Open Access Journals (Sweden)

    Peter Goodin

    Full Text Available Binaural beats are an auditory phenomenon that has been suggested to alter physiological and cognitive processes including vigilance and brainwave entrainment. Some personality traits measured by the NEO Five Factor Model have been found to alter entrainment using pulsing light stimuli, but as yet no studies have examined if this occurs using steady state presentation of binaural beats for a relatively short presentation of two minutes. This study aimed to examine if binaural beat stimulation altered vigilance or cortical frequencies and if personality traits were involved. Thirty-one participants were played binaural beat stimuli designed to elicit a response at either the Theta (7 Hz or Beta (16 Hz frequency bands while undertaking a zero-back vigilance task. EEG was recorded from a high-density electrode cap. No significant differences were found in vigilance or cortical frequency power during binaural beat stimulation compared to a white noise control period. Furthermore, no significant relationships were detected between the above and the Big Five personality traits. This suggests a short presentation of steady state binaural beats are not sufficient to alter vigilance or entrain cortical frequencies at the two bands examined and that certain personality traits were not more susceptible than others.

  2. Effect of depth beating on the fiber properties and enzymatic saccharification efficiency of softwood kraft pulp.

    Science.gov (United States)

    Gao, Wenhua; Xiang, Zhouyang; Chen, Kefu; Yang, Rendang; Yang, Fei

    2015-01-01

    Commercial bleached softwood kraft pulp was mechanically fibrillated by a PFI-mill with beating revolution from 5000 to 30,000 r. The extent of fibrillating on the pulp was evaluated by beating degree, fiber morphological properties (fiber length, width, coarseness and curls index), water retention value (WRV) and physical properties of paper made from the pulp. Depth beating process significantly affected the pulp fibrillations as showed by the decreased fiber length and width as well as the SEM analysis, but the effects were limited after beating revolution of 15,000. Depth beating process also improved the total internal pore and inter-fibril surface areas as shown by the increased WRV values. Substrate enzymatic digestibility (SED) of beaten pulp at 5000 revolutions could reach 95% at cellulase loading of 15 FPU/g of glucan. After the enzymatic hydrolysis, the size of the pulp residues was reduced to micro-scale, and a relative uniform size distribution of the residues appeared at 10,000 r beating revolution. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Human cortical responses to slow and fast binaural beats reveal multiple mechanisms of binaural hearing.

    Science.gov (United States)

    Ross, Bernhard; Miyazaki, Takahiro; Thompson, Jessica; Jamali, Shahab; Fujioka, Takako

    2014-10-15

    When two tones with slightly different frequencies are presented to both ears, they interact in the central auditory system and induce the sensation of a beating sound. At low difference frequencies, we perceive a single sound, which is moving across the head between the left and right ears. The percept changes to loudness fluctuation, roughness, and pitch with increasing beat rate. To examine the neural representations underlying these different perceptions, we recorded neuromagnetic cortical responses while participants listened to binaural beats at a continuously varying rate between 3 Hz and 60 Hz. Binaural beat responses were analyzed as neuromagnetic oscillations following the trajectory of the stimulus rate. Responses were largest in the 40-Hz gamma range and at low frequencies. Binaural beat responses at 3 Hz showed opposite polarity in the left and right auditory cortices. We suggest that this difference in polarity reflects the opponent neural population code for representing sound location. Binaural beats at any rate induced gamma oscillations. However, the responses were largest at 40-Hz stimulation. We propose that the neuromagnetic gamma oscillations reflect postsynaptic modulation that allows for precise timing of cortical neural firing. Systematic phase differences between bilateral responses suggest that separate sound representations of a sound object exist in the left and right auditory cortices. We conclude that binaural processing at the cortical level occurs with the same temporal acuity as monaural processing whereas the identification of sound location requires further interpretation and is limited by the rate of object representations. Copyright © 2014 the American Physiological Society.

  4. A high-density EEG investigation into steady state binaural beat stimulation.

    Science.gov (United States)

    Goodin, Peter; Ciorciari, Joseph; Baker, Kate; Carey, Anne-Marie; Carrey, Anne-Marie; Harper, Michelle; Kaufman, Jordy

    2012-01-01

    Binaural beats are an auditory phenomenon that has been suggested to alter physiological and cognitive processes including vigilance and brainwave entrainment. Some personality traits measured by the NEO Five Factor Model have been found to alter entrainment using pulsing light stimuli, but as yet no studies have examined if this occurs using steady state presentation of binaural beats for a relatively short presentation of two minutes. This study aimed to examine if binaural beat stimulation altered vigilance or cortical frequencies and if personality traits were involved. Thirty-one participants were played binaural beat stimuli designed to elicit a response at either the Theta (7 Hz) or Beta (16 Hz) frequency bands while undertaking a zero-back vigilance task. EEG was recorded from a high-density electrode cap. No significant differences were found in vigilance or cortical frequency power during binaural beat stimulation compared to a white noise control period. Furthermore, no significant relationships were detected between the above and the Big Five personality traits. This suggests a short presentation of steady state binaural beats are not sufficient to alter vigilance or entrain cortical frequencies at the two bands examined and that certain personality traits were not more susceptible than others.

  5. Neural responses to sounds presented on and off the beat of ecologically valid music

    Directory of Open Access Journals (Sweden)

    Adam eTierney

    2013-05-01

    Full Text Available The tracking of rhythmic structure is a vital component of speech and music perception. It is known that sequences of identical sounds can give rise to the percept of alternating strong and weak sounds, and that this percept is linked to enhanced cortical and oscillatory responses. The neural correlates of the perception of rhythm elicited by ecologically valid, complex stimuli, however, remain unexplored. Here we report the effects of a stimulus’ alignment with the beat on the brain’s processing of sound. Human subjects listened to short popular music pieces while simultaneously hearing a target sound. Cortical and brainstem electrophysiological onset responses to the sound were enhanced when it was presented on the beat of the music, as opposed to shifted away from it. Moreover, the size of the effect of alignment with the beat on the cortical response correlated strongly with the ability to tap to a beat, suggesting that the ability to synchronize to the beat of simple isochronous stimuli and the ability to track the beat of complex, ecologically valid stimuli may rely on overlapping neural resources. These results suggest that the perception of musical rhythm may have robust effects on processing throughout the auditory system.

  6. Accuracy of conventional transthoracic echocardiography for the diagnosis of intracardiac right-to-left shunt: a meta-analysis of prospective studies.

    Science.gov (United States)

    Mojadidi, Mohammad Khalid; Winoker, Jared S; Roberts, Scott C; Msaouel, Pavlos; Zaman, Muhammad Omer; Gevorgyan, Rubine; Tobis, Jonathan M

    2014-10-01

    Paradoxical embolization through a right-to-left shunt (RLS), often from a patent foramen ovale (PFO), has been associated with cryptogenic stroke. While transesophageal echo (TEE) bubble study is the current standard reference for diagnosing PFO, transthoracic echo (TTE) remains the most commonly used screening test for RLS due to its noninvasiveness and easy availability. The aim of this meta-analysis was to determine the accuracy of TTE compared to TEE as the reference. A systematic review of Medline, Cochrane, and Embase was done to look for all the prospective studies assessing for intracardiac RLS using conventional TTE compared to TEE as the reference; both TTE and TEE were performed with a contrast agent and a maneuver to provoke RLS in all studies. A total of 13 studies with 1436 patients fulfilled the inclusion criteria. The weighted mean sensitivity and specificity for TTE were 46% and 99%, respectively. Likewise, the positive likelihood ratio and negative likelihood ratio were 20.85 and 0.57, respectively. Using different contrast agents, different microbubble cutoffs for a positive TTE/TEE, and different cardiac cycle cutoffs for a positive TTE/TEE did not affect the accuracy of TTE. In a population of patients with cryptogenic stroke, a TTE that tests positive for RLS has a 95% probability of being a true positive. Transthoracic echocardiogram has a low sensitivity and extremely high specificity, making it a poor rule out test but an excellent rule in test for the detection of intracardiac RLS. © 2014, Wiley Periodicals, Inc.

  7. Influence of ECG sampling rate in fetal heart rate variability analysis.

    Science.gov (United States)

    De Jonckheere, J; Garabedian, C; Charlier, P; Champion, C; Servan-Schreiber, E; Storme, L; Debarge, V; Jeanne, M; Logier, R

    2017-07-01

    Fetal hypoxia results in a fetal blood acidosis (pHheart rate variability in hypoxic fetuses. So, fetal heart rate variability analysis could be of precious help for fetal hypoxia prediction. Commonly used fetal heart rate variability analysis methods have been shown to be sensitive to the ECG signal sampling rate. Indeed, a low sampling rate could induce variability in the heart beat detection which will alter the heart rate variability estimation. In this paper, we introduce an original fetal heart rate variability analysis method. We hypothesize that this method will be less sensitive to ECG sampling frequency changes than common heart rate variability analysis methods. We then compared the results of this new heart rate variability analysis method with two different sampling frequencies (250-1000 Hz).

  8. The role of stents in the treatment of congenital heart disease: Current status and future perspectives

    International Nuclear Information System (INIS)

    Peters, Bjoern; Ewert, Peter; Berger, Felix

    2009-01-01

    Intravascular or intracardiac stenoses occur in many forms of congenital heart disease (CHD). Therefore, the implantation of stents has become an accepted interventional procedure for stenotic lesions in pediatric cardiology. Furthermore, stents are know to be used to exclude vessel aneurysm or to ensure patency of existing or newly created intracardiac communications. With the further refinement of the first generation of devices, a variety of “modern” stents with different design characteristics have evolved. Despite the tremendous technical improvement over the last 20 years, the “ideal stent” has not yet been developed. Therefore, the pediatric interventionalist has to decide which stent is suitable for each lesion. On this basis, currently available stents are discussed in regard to their advantages and disadvantages for common application in CHD. New concepts and designs developed to overcome some of the existing problems, like the failure of adaptation to somatic growth, are presented. Thus, in the future, biodegradable or growth stents might replace the currently used generation of stents. This might truly lead to widening indications for the use of stents in the treatment of CHD

  9. The role of stents in the treatment of congenital heart disease: Current status and future perspectives

    Directory of Open Access Journals (Sweden)

    Peters Bjoern

    2009-01-01

    Full Text Available Intravascular or intracardiac stenoses occur in many forms of congenital heart disease (CHD. Therefore, the implantation of stents has become an accepted interventional procedure for stenotic lesions in pediatric cardiology. Furthermore, stents are know to be used to exclude vessel aneurysm or to ensure patency of existing or newly created intracardiac communications. With the further refinement of the first generation of devices, a variety of "modern" stents with different design characteristics have evolved. Despite the tremendous technical improvement over the last 20 years, the "ideal stent" has not yet been developed. Therefore, the pediatric interventionalist has to decide which stent is suitable for each lesion. On this basis, currently available stents are discussed in regard to their advantages and disadvantages for common application in CHD. New concepts and designs developed to overcome some of the existing problems, like the failure of adaptation to somatic growth, are presented. Thus, in the future, biodegradable or growth stents might replace the currently used generation of stents. This might truly lead to widening indications for the use of stents in the treatment of CHD.

  10. Heart rate variability - a historical perspective.

    Science.gov (United States)

    Billman, George E

    2011-01-01

    Heart rate variability (HRV), the beat-to-beat variation in either heart rate or the duration of the R-R interval - the heart period, has become a popular clinical and investigational tool. The temporal fluctuations in heart rate exhibit a marked synchrony with respiration (increasing during inspiration and decreasing during expiration - the so called respiratory sinus arrhythmia, RSA) and are widely believed to reflect changes in cardiac autonomic regulation. Although the exact contributions of the parasympathetic and the sympathetic divisions of the autonomic nervous system to this variability are controversial and remain the subject of active investigation and debate, a number of time and frequency domain techniques have been developed to provide insight into cardiac autonomic regulation in both health and disease. It is the purpose of this essay to provide an historical overview of the evolution in the concept of HRV. Briefly, pulse rate was first measured by ancient Greek physicians and scientists. However, it was not until the invention of the "Physician's Pulse Watch" (a watch with a second hand that could be stopped) in 1707 that changes in pulse rate could be accurately assessed. The Rev. Stephen Hales (1733) was the first to note that pulse varied with respiration and in 1847 Carl Ludwig was the first to record RSA. With the measurement of the ECG (1895) and advent of digital signal processing techniques in the 1960s, investigation of HRV and its relationship to health and disease has exploded. This essay will conclude with a brief description of time domain, frequency domain, and non-linear dynamic analysis techniques (and their limitations) that are commonly used to measure HRV.

  11. Heart Rate Variability – A Historical Perspective

    Science.gov (United States)

    Billman, George E.

    2011-01-01

    Heart rate variability (HRV), the beat-to-beat variation in either heart rate or the duration of the R–R interval – the heart period, has become a popular clinical and investigational tool. The temporal fluctuations in heart rate exhibit a marked synchrony with respiration (increasing during inspiration and decreasing during expiration – the so called respiratory sinus arrhythmia, RSA) and are widely believed to reflect changes in cardiac autonomic regulation. Although the exact contributions of the parasympathetic and the sympathetic divisions of the autonomic nervous system to this variability are controversial and remain the subject of active investigation and debate, a number of time and frequency domain techniques have been developed to provide insight into cardiac autonomic regulation in both health and disease. It is the purpose of this essay to provide an historical overview of the evolution in the concept of HRV. Briefly, pulse rate was first measured by ancient Greek physicians and scientists. However, it was not until the invention of the “Physician’s Pulse Watch” (a watch with a second hand that could be stopped) in 1707 that changes in pulse rate could be accurately assessed. The Rev. Stephen Hales (1733) was the first to note that pulse varied with respiration and in 1847 Carl Ludwig was the first to record RSA. With the measurement of the ECG (1895) and advent of digital signal processing techniques in the 1960s, investigation of HRV and its relationship to health and disease has exploded. This essay will conclude with a brief description of time domain, frequency domain, and non-linear dynamic analysis techniques (and their limitations) that are commonly used to measure HRV. PMID:22144961

  12. Optimum heart sound signal selection based on the cyclostationary property.

    Science.gov (United States)

    Li, Ting; Qiu, Tianshuang; Tang, Hong

    2013-07-01

    Noise often appears in parts of heart sound recordings, which may be much longer than those necessary for subsequent automated analysis. Thus, human intervention is needed to select the heart sound signal with the best quality or the least noise. This paper presents an automatic scheme for optimum sequence selection to avoid such human intervention. A quality index, which is based on finding that sequences with less random noise contamination have a greater degree of periodicity, is defined on the basis of the cyclostationary property of heart beat events. The quality score indicates the overall quality of a sequence. No manual intervention is needed in the process of subsequence selection, thereby making this scheme useful in automatic analysis of heart sound signals. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Heart MRI

    Science.gov (United States)

    ... Heart defibrillator or pacemaker Inner ear (cochlear) implants Kidney disease or dialysis (you may not be able to receive contrast) Recently placed artificial joints Certain types of vascular stents Worked with ...

  14. Heart Attack

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    ... pain Fatigue Heart attack Symptoms & causes Diagnosis & treatment Advertisement Mayo Clinic does not endorse companies or products. ... a Job Site Map About This Site Twitter Facebook Google YouTube Pinterest Mayo Clinic is a not- ...

  15. Heart Block

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    ... graph show each step of an electrical signal's journey through the heart. EKG The image shows the ... and Usage No FEAR Act Grants and Funding Customer Service/Center for Health Information Email Alerts Jobs ...

  16. Heart Truth

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    ... the stories that unite us in a shared journey toward better heart health. Hear from our new ... and Usage No FEAR Act Grants and Funding Customer Service/Center for Health Information Email Alerts Jobs ...

  17. About Heart Attacks

    Science.gov (United States)

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More About Heart Attacks Updated:Jan 11,2018 A heart attack is ... coronary artery damage leads to a heart attack . Heart Attack Questions and Answers What is a heart attack? ...

  18. Types of Heart Failure

    Science.gov (United States)

    ... Venous Thromboembolism Aortic Aneurysm More Types of Heart Failure Updated:May 8,2017 Left-sided heart failure ... This content was last reviewed May 2017. Heart Failure • Home • About Heart Failure Introduction Types of Heart ...

  19. Nonlinear and stochastic dynamics in the heart

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Zhilin, E-mail: zqu@mednet.ucla.edu [Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, CA 90095 (United States); Hu, Gang [Department of Physics, Beijing Normal University, Beijing 100875 (China); Garfinkel, Alan [Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, CA 90095 (United States); Department of Integrative Biology and Physiology, University of California, Los Angeles, CA 90095 (United States); Weiss, James N. [Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, CA 90095 (United States); Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095 (United States)

    2014-10-10

    In a normal human life span, the heart beats about 2–3 billion times. Under diseased conditions, a heart may lose its normal rhythm and degenerate suddenly into much faster and irregular rhythms, called arrhythmias, which may lead to sudden death. The transition from a normal rhythm to an arrhythmia is a transition from regular electrical wave conduction to irregular or turbulent wave conduction in the heart, and thus this medical problem is also a problem of physics and mathematics. In the last century, clinical, experimental, and theoretical studies have shown that dynamical theories play fundamental roles in understanding the mechanisms of the genesis of the normal heart rhythm as well as lethal arrhythmias. In this article, we summarize in detail the nonlinear and stochastic dynamics occurring in the heart and their links to normal cardiac functions and arrhythmias, providing a holistic view through integrating dynamics from the molecular (microscopic) scale, to the organelle (mesoscopic) scale, to the cellular, tissue, and organ (macroscopic) scales. We discuss what existing problems and challenges are waiting to be solved and how multi-scale mathematical modeling and nonlinear dynamics may be helpful for solving these problems.

  20. Nonlinear and stochastic dynamics in the heart

    International Nuclear Information System (INIS)

    Qu, Zhilin; Hu, Gang; Garfinkel, Alan; Weiss, James N.

    2014-01-01

    In a normal human life span, the heart beats about 2–3 billion times. Under diseased conditions, a heart may lose its normal rhythm and degenerate suddenly into much faster and irregular rhythms, called arrhythmias, which may lead to sudden death. The transition from a normal rhythm to an arrhythmia is a transition from regular electrical wave conduction to irregular or turbulent wave conduction in the heart, and thus this medical problem is also a problem of physics and mathematics. In the last century, clinical, experimental, and theoretical studies have shown that dynamical theories play fundamental roles in understanding the mechanisms of the genesis of the normal heart rhythm as well as lethal arrhythmias. In this article, we summarize in detail the nonlinear and stochastic dynamics occurring in the heart and their links to normal cardiac functions and arrhythmias, providing a holistic view through integrating dynamics from the molecular (microscopic) scale, to the organelle (mesoscopic) scale, to the cellular, tissue, and organ (macroscopic) scales. We discuss what existing problems and challenges are waiting to be solved and how multi-scale mathematical modeling and nonlinear dynamics may be helpful for solving these problems

  1. Heart Rate Responses of a Head Referee During a Football Game.

    Science.gov (United States)

    Conti, D J; McClintock, S L

    1983-10-01

    In brief: To determine the heart rate responses of a football official to both physical and psychological stress during actual game conditions, a head referee was telemetered continuously from one- half hour before until the end of a college football game. The referee's cardiac system was stressed throughout the monitoring period: The highest average heart rate was 161 beats min(-1) (85% of maximum), and the lowest average heart rate was 140 beats min(-1) (74% of maximum). Because officiating is largely anaerobic, the sustained sinus tachycardia was probably caused by psychological stress. Football officials should have a maximal ECG stress test every year and participate in an aerobic conditioning program on a regular basis.

  2. Aerobic exercise during pregnancy and presence of fetal-maternal heart rate synchronization.

    Directory of Open Access Journals (Sweden)

    Peter Van Leeuwen

    Full Text Available It has been shown that short-term direct interaction between maternal and fetal heart rates may take place and that this interaction is affected by the rate of maternal respiration. The aim of this study was to determine the effect of maternal aerobic exercise during pregnancy on the occurrence of fetal-maternal heart rate synchronization.In 40 pregnant women at the 36th week of gestation, 21 of whom exercised regularly, we acquired 18 min. RR interval time series obtained simultaneously in the mothers and their fetuses from magnetocardiographic recordings. The time series of the two groups were examined with respect to their heart rate variability, the maternal respiratory rate and the presence of synchronization epochs as determined on the basis of synchrograms. Surrogate data were used to assess whether the occurrence of synchronization was due to chance.In the original data, we found synchronization occurred less often in pregnancies in which the mothers had exercised regularly. These subjects also displayed higher combined fetal-maternal heart rate variability and lower maternal respiratory rates. Analysis of the surrogate data showed shorter epochs of synchronization and a lack of the phase coordination found between maternal and fetal beat timing in the original data.The results suggest that fetal-maternal heart rate coupling is present but generally weak. Maternal exercise has a damping effect on its occurrence, most likely due to an increase in beat-to-beat differences, higher vagal tone and slower breathing rates.

  3. Gender- and age-related differences in heart rate dynamics: are women more complex than men?

    Science.gov (United States)

    Ryan, S. M.; Goldberger, A. L.; Pincus, S. M.; Mietus, J.; Lipsitz, L. A.

    1994-01-01

    OBJECTIVES. This study aimed to quantify the complex dynamics of beat-to-beat sinus rhythm heart rate fluctuations and to determine their differences as a function of gender and age. BACKGROUND. Recently, measures of heart rate variability and the nonlinear "complexity" of heart rate dynamics have been used as indicators of cardiovascular health. Because women have lower cardiovascular risk and greater longevity than men, we postulated that there are important gender-related differences in beat-to-beat heart rate dynamics. METHODS. We analyzed heart rate dynamics during 8-min segments of continuous electrocardiographic recording in healthy young (20 to 39 years old), middle-aged (40 to 64 years old) and elderly (65 to 90 years old) men (n = 40) and women (n = 27) while they performed spontaneous and metronomic (15 breaths/min) breathing. Relatively high (0.15 to 0.40 Hz) and low (0.01 to 0.15 Hz) frequency components of heart rate variability were computed using spectral analysis. The overall "complexity" of each heart rate time series was quantified by its approximate entropy, a measure of regularity derived from nonlinear dynamics ("chaos" theory). RESULTS. Mean heart rate did not differ between the age groups or genders. High frequency heart rate power and the high/low frequency power ratio decreased with age in both men and women (p < 0.05). The high/low frequency power ratio during spontaneous and metronomic breathing was greater in women than men (p < 0.05). Heart rate approximate entropy decreased with age and was higher in women than men (p < 0.05). CONCLUSIONS. High frequency heart rate spectral power (associated with parasympathetic activity) and the overall complexity of heart rate dynamics are higher in women than men. These complementary findings indicate the need to account for gender-as well as age-related differences in heart rate dynamics. Whether these gender differences are related to lower cardiovascular disease risk and greater longevity in

  4. To beat or not to beat a tick: comparison of DNA extraction methods for ticks (Ixodes scapularis

    Directory of Open Access Journals (Sweden)

    Alyssa D. Ammazzalorso

    2015-08-01

    Full Text Available Background. Blacklegged ticks (Ixodes scapularis are important disease vectors in the United States, known to transmit a variety of pathogens to humans, including bacteria, protozoa, and viruses. Their importance as a disease vector necessitates reliable and comparable methods for extracting microbial DNA from ticks. Furthermore, to explore the population genetics or genomics of this tick, appropriate DNA extraction techniques are needed for both the vector and its microbes. Although a few studies have investigated different methods of DNA isolation from ticks, they are limited in the number and types of DNA extraction and lack species-specific quantification of DNA yield.Methods. Here we determined the most efficient and consistent method of DNA extraction from two different developmental stages of I. scapularis—nymph and adult—that are the most important for disease transmission. We used various methods of physical disruption of the hard, chitinous exoskeleton, as well as commercial and non-commercial DNA isolation kits. To gauge the effectiveness of these methods, we quantified the DNA yield and confirmed the DNA quality via PCR of both tick and microbial genetic material.Results. DNA extraction using the Thermo GeneJET Genomic DNA Purification Kit resulted in the highest DNA yields and the most consistent PCR amplification when combined with either cutting or bead beating with select matrices across life stages. DNA isolation methods using ammonium hydroxide as well as the MoBio PowerSoil kit also produced strong and successful PCR amplification, but only for females.Discussion. We contrasted a variety of readily available methods of DNA extraction from single individual blacklegged ticks and presented the results through a quantitative and qualitative assessment.

  5. Imaging of ischemic heart disease

    International Nuclear Information System (INIS)

    Lipton, Martin J.; Reba, Richard C.; Bogaert, Jan; Boxt, Larry M.

    2002-01-01

    Despite advances in the understanding and treatment of ischemic cardiomyopathy, characterized by extensive coronary artery disease and left ventricular (LV) dysfunction, the prognosis remains poor with only a 50-60% 5-year survival rate. The composition of atherosclerotic lesions is currently regarded as being more important than the degree of stenosis in determining acute events. If imaging techniques could distinguish vulnerable from stable plaques, then high-risk patient subgroups could be identified. Another important concept is that LV dysfunction may be the result of either scarring due to necrosis or to the presence of myocardial hibernation, in which there is sufficient blood flow to sustain viable myocytes, but insufficient to maintain systolic contraction. This concept of myocardial viability is critical for making optimal clinical management decisions. This review describes how noninvasive imaging methods can be used to distinguish regions of irreversibly injured myocardium from viable but hibernating segments. Technical advances in CT and MR have made imaging of the beating heart possible. Considerable clinical progress has already been made and further cardiac applications are expected. Radiologists therefore have new opportunities for involvement in cardiac imaging but must recognize the political implications as well as the diagnostic potential of these modalities not only for the heart, but also for the whole vascular system. This review focuses on imaging myocardial injury. It compares state-of-the-art CT and MR with more established yet contemporary echocardiography and nuclear scintigraphy. (orig.)

  6. Comparison of the measurement of heart rate in adult free-range chickens (Gallus domesticus) by auscultation and electrocardiography.

    Science.gov (United States)

    Smith, C F; Gavaghan, B J; McSweeney, D; Powell, V; Lisle, A

    2014-12-01

    To compare the heart rates of adult free-range chickens (Gallus domesticus) measured by auscultation with a stethoscope with those measured simultaneously using electrocardiography (ECG). With each bird in a standing position, estimation of the heart rate was performed by placing a mark on paper for every 4 beats for roosters and 8 beats for hens as detected by auscultation over 30 s, while simultaneous ECG was performed. Heart rates measured by auscultation showed a high correlation (r = 0.97) with those measured by ECG. There was a high correlation between the heart rates of adult free-range chickens measured by auscultation with a stethoscope and those measured simultaneously using ECG. © 2014 Australian Veterinary Association.

  7. The effect of gamma-enhancing binaural beats on the control of feature bindings.

    Science.gov (United States)

    Colzato, Lorenza S; Steenbergen, Laura; Sellaro, Roberta

    2017-07-01

    Binaural beats represent the auditory experience of an oscillating sound that occurs when two sounds with neighboring frequencies are presented to one's left and right ear separately. Binaural beats have been shown to impact information processing via their putative role in increasing neural synchronization. Recent studies of feature-repetition effects demonstrated interactions between perceptual features and action-related features: repeating only some, but not all features of a perception-action episode hinders performance. These partial-repetition (or binding) costs point to the existence of temporary episodic bindings (event files) that are automatically retrieved by repeating at least one of their features. Given that neural synchronization in the gamma band has been associated with visual feature bindings, we investigated whether the impact of binaural beats extends to the top-down control of feature bindings. Healthy adults listened to gamma-frequency (40 Hz) binaural beats or to a constant tone of 340 Hz (control condition) for ten minutes before and during a feature-repetition task. While the size of visuomotor binding costs (indicating the binding of visual and action features) was unaffected by the binaural beats, the size of visual feature binding costs (which refer to the binding between the two visual features) was considerably smaller during gamma-frequency binaural beats exposure than during the control condition. Our results suggest that binaural beats enhance selectivity in updating episodic memory traces and further strengthen the hypothesis that neural activity in the gamma band is critically associated with the control of feature binding.

  8. Electrophysiological measurement of binaural beats: effects of primary tone frequency and observer age.

    Science.gov (United States)

    Grose, John H; Mamo, Sara K

    2012-01-01

    The purpose of this study was to determine the reliability of the electrophysiological binaural beat steady state response as a gauge of temporal fine structure coding, particularly as it relates to the aging auditory system. The hypothesis was that the response would be more robust in a lower, than in a higher, frequency region and in younger, than in older, adults. Two experiments were undertaken. The first measured the 40 Hz binaural beat steady state response elicited by tone pairs in two frequency regions: lower (390 and 430 Hz tone pair) and higher (810 and 850 Hz tone pair). Frequency following responses (FFRs) evoked by the tones were also recorded. Ten young adults with normal hearing participated. The second experiment measured the binaural beat and FFRs in older adults but only in the lower frequency region. Fourteen older adults with relatively normal hearing participated. Response metrics in both experiments included response component signal-to-noise ratio (F statistic) and magnitude-squared coherence. Experiment 1 showed that FFRs were elicited in both frequency regions but were more robust in the lower frequency region. Binaural beat responses elicited by the lower frequency pair of tones showed greater amplitude fluctuation within a participant than the respective FFRs. Experiment 2 showed that older adults exhibited similar FFRs to younger adults, but proportionally fewer older participants showed binaural beat responses. Age differences in onset responses were also observed. The lower prevalence of the binaural beat response in older adults, despite the presence of FFRs, provides tentative support for the sensitivity of this measure to age-related deficits in temporal processing. However, the lability of the binaural beat response advocates caution in its use as an objective measure of fine structure coding.

  9. Binaural beat technology in humans: a pilot study to assess psychologic and physiologic effects.

    Science.gov (United States)

    Wahbeh, Helané; Calabrese, Carlo; Zwickey, Heather

    2007-01-01

    Binaural beat technology (BBT) products are sold internationally as personal development and health improvement tools. Producers suggest benefit from regular listening to binaural beats including reduced stress and anxiety, and increased focus, concentration, motivation, confidence, and depth in meditation. Binaural beats are auditory brainstem responses that originate in the superior olivary nucleus as a result of different frequency auditory stimuli provided to each ear. Listeners to binaural beat "hear" a beat at a frequency equal to the difference between the frequencies of the applied tones. The objectives of this pilot study were to gather preliminary data on psychologic and physiologic effects of 60 days daily use of BBT for hypothesis generation and to assess compliance, feasibility, and safety for future studies. Uncontrolled pilot study. Eight healthy adults participated in the study. Participants listened to a CD with delta (0-4 Hz) binaural beat frequencies daily for 60 days. Psychologic and physiological data were collected before and after a 60-day intervention. PSYCHOLOGIC: Depression (Beck Depression Inventory-2), anxiety (State-Trait Anxiety Inventory), mood (Profile of Mood States), absorption (Tellegen Absorption Scale) and quality of Life (World Health Organization-Quality of Life Inventory). PHYSIOLOGICAL: Cortisol, dehydroepiandrosterone, melatonin, insulin-like growth factor-1, serotonin, dopamine, epinephrine, norepinephrine, weight, blood pressure, high sensitivity C-reactive protein. There was a decrease in trait anxiety (p = 0.004), an increase in quality of life (p = 0.03), and a decrease in insulin-like growth factor-1 (p = 0.01) and dopamine (p = 0.02) observed between pre- and postintervention measurements. Binaural beat technology may exhibit positive effect on self-reported psychologic measures, especially anxiety. Further research is warranted to explore the effects on anxiety using a larger, randomized and controlled trial.

  10. Modulations of Heart Rate, ECG, and Cardio-Respiratory Coupling Observed in Polysomnography

    Directory of Open Access Journals (Sweden)

    Thomas Penzel

    2016-10-01

    Full Text Available The cardiac component of cardio-respiratory polysomnography is covered by ECG and heart rate recordings. However their evaluation is often underrepresented in summarizing reports. As complements to EEG, EOG, and EMG, these signals provide diagnostic information for autonomic nervous activity during sleep. This review presents major methodological developments in sleep research regarding heart rate, ECG and cardio-respiratory couplings in a chronological (historical sequence. It presents physiological and pathophysiological insights related to sleep medicine obtained by new technical developments. Recorded nocturnal ECG facilitates conventional heart rate variability analysis, studies of cyclical variations of heart rate, and analysis of ECG waveform. In healthy adults, the autonomous nervous system is regulated in totally different ways during wakefulness, slow-wave sleep, and REM sleep. Analysis of beat-to-beat heart-rate variations with statistical methods enables us to estimate sleep stages based on the differences in autonomic nervous system regulation. Furthermore, up to some degree, it is possible to track transitions from wakefulness to sleep by analysis of heart-rate variations. ECG and heart rate analysis allow assessment of selected sleep disorders as well. Sleep disordered breathing can be detected reliably by studying cyclical variation of heart rate combined with respiration-modulated changes in ECG morphology (amplitude of R wave and T wave.

  11. Signal processing of heart signals for the quantification of non-deterministic events

    Directory of Open Access Journals (Sweden)

    Baddour Natalie

    2011-01-01

    Full Text Available Abstract Background Heart signals represent an important way to evaluate cardiovascular function and often what is desired is to quantify the level of some signal of interest against the louder backdrop of the beating of the heart itself. An example of this type of application is the quantification of cavitation in mechanical heart valve patients. Methods An algorithm is presented for the quantification of high-frequency, non-deterministic events such as cavitation from recorded signals. A closed-form mathematical analysis of the algorithm investigates its capabilities. The algorithm is implemented on real heart signals to investigate usability and implementation issues. Improvements are suggested to the base algorithm including aligning heart sounds, and the implementation of the Short-Time Fourier Transform to study the time evolution of the energy in the signal. Results The improvements result in better heart beat alignment and better detection and measurement of the random events in the heart signals, so that they may provide a method to quantify nondeterministic events in heart signals. The use of the Short-Time Fourier Transform allows the examination of the random events in both time and frequency allowing for further investigation and interpretation of the signal. Conclusions The presented algorithm does allow for the quantification of nondeterministic events but proper care in signal acquisition and processing must be taken to obtain meaningful results.

  12. Signal processing of heart signals for the quantification of non-deterministic events.

    Science.gov (United States)

    Millette, Véronique; Baddour, Natalie

    2011-01-26

    Heart signals represent an important way to evaluate cardiovascular function and often what is desired is to quantify the level of some signal of interest against the louder backdrop of the beating of the heart itself. An example of this type of application is the quantification of cavitation in mechanical heart valve patients. An algorithm is presented for the quantification of high-frequency, non-deterministic events such as cavitation from recorded signals. A closed-form mathematical analysis of the algorithm investigates its capabilities. The algorithm is implemented on real heart signals to investigate usability and implementation issues. Improvements are suggested to the base algorithm including aligning heart sounds, and the implementation of the Short-Time Fourier Transform to study the time evolution of the energy in the signal. The improvements result in better heart beat alignment and better detection and measurement of the random events in the heart signals, so that they may provide a method to quantify nondeterministic events in heart signals. The use of the Short-Time Fourier Transform allows the examination of the random events in both time and frequency allowing for further investigation and interpretation of the signal. The presented algorithm does allow for the quantification of nondeterministic events but proper care in signal acquisition and processing must be taken to obtain meaningful results.

  13. Time-lapse imaging of human heart motion with switched array UWB radar.

    Science.gov (United States)

    Brovoll, Sverre; Berger, Tor; Paichard, Yoann; Aardal, Øyvind; Lande, Tor Sverre; Hamran, Svein-Erik

    2014-10-01

    Radar systems for detection of human heartbeats have mostly been single-channel systems with limited spatial resolution. In this paper, a radar system for ultra-wideband (UWB) imaging of the human heart is presented. To make the radar waves penetrate the human tissue the antenna is placed very close to the body. The antenna is an array with eight elements, and an antenna switch system connects the radar to the individual elements in sequence to form an image. Successive images are used to build up time-lapse movies of the beating heart. Measurements on a human test subject are presented and the heart motion is estimated at different locations inside the body. The movies show rhythmic motion consistent with the beating heart, and the location and shape of the reflections correspond well with the expected response form the heart wall. The spatial dependent heart motion is compared to ECG recordings, and it is confirmed that heartbeat modulations are seen in the radar data. This work shows that radar imaging of the human heart may provide valuable information on the mechanical movement of the heart.

  14. Effects of thyroid state on respiration of perfused rat and guinea pig hearts

    Energy Technology Data Exchange (ETDEWEB)

    Read, L.C.; Wallace, P.G.; Berry, M.N. (Flinders Univ. School of Medicine, Bedford Park (Australia))

    1987-09-01

    The effects of thyroid state on the respiration of the isolated heart were investigated using retrograde perfused rat and guinea pig hearts. In both species, hypothyroidism caused a marked depression in circulating thyroid hormone concentrations and in the respiration of the isolated, retrograde perfused heart. Hypothyroidism was caused by injecting animals with Na{sup 131}I. The effects on myocardial respiration could be attributed to changes in the contraction frequency and in the oxygen consumption per beat, with little contribution from basal respiration. Treatment of animals with thyroxine elevated plasma thyroid hormones to a similar extent in rats and guinea pigs. In the latter, thyroxine treatment was associated with substantial increases in the contraction frequency and the oxygen consumption per beat of the isolated heart. In contrast, only small changes were apparent in the retrograde perfused rat heart, observations that were confirmed in rat hearts perfused at near physiological work loads. It was concluded that rat hearts isolated from normal animals function at near maximal thyroid state, in contrast to the guinea pig heart, which requires higher circulating concentrations of thyroid hormones to attain maximal responses.

  15. Effects of thyroid state on respiration of perfused rat and guinea pig hearts

    International Nuclear Information System (INIS)

    Read, L.C.; Wallace, P.G.; Berry, M.N.

    1987-01-01

    The effects of thyroid state on the respiration of the isolated heart were investigated using retrograde perfused rat and guinea pig hearts. In both species, hypothyroidism caused a marked depression in circulating thyroid hormone concentrations and in the respiration of the isolated, retrograde perfused heart. Hypothyroidism was caused by injecting animals with Na 131 I. The effects on myocardial respiration could be attributed to changes in the contraction frequency and in the oxygen consumption per beat, with little contribution from basal respiration. Treatment of animals with thyroxine elevated plasma thyroid hormones to a similar extent in rats and guinea pigs. In the latter, thyroxine treatment was associated with substantial increases in the contraction frequency and the oxygen consumption per beat of the isolated heart. In contrast, only small changes were apparent in the retrograde perfused rat heart, observations that were confirmed in rat hearts perfused at near physiological work loads. It was concluded that rat hearts isolated from normal animals function at near maximal thyroid state, in contrast to the guinea pig heart, which requires higher circulating concentrations of thyroid hormones to attain maximal responses

  16. Modulations of Heart Rate, ECG, and Cardio-Respiratory Coupling Observed in Polysomnography.

    Science.gov (United States)

    Penzel, Thomas; Kantelhardt, Jan W; Bartsch, Ronny P; Riedl, Maik; Kraemer, Jan F; Wessel, Niels; Garcia, Carmen; Glos, Martin; Fietze, Ingo; Schöbel, Christoph

    2016-01-01

    The cardiac component of cardio-respiratory polysomnography is covered by ECG and heart rate recordings. However, their evaluation is often underrepresented in summarizing reports. As complements to EEG, EOG, and EMG, these signals provide diagnostic information for autonomic nervous activity during sleep. This review presents major methodological developments in sleep research regarding heart rate, ECG, and cardio-respiratory couplings in a chronological (historical) sequence. It presents physiological and pathophysiological insights related to sleep medicine obtained by new technical developments. Recorded nocturnal ECG facilitates conventional heart rate variability (HRV) analysis, studies of cyclical variations of heart rate, and analysis of ECG waveform. In healthy adults, the autonomous nervous system is regulated in totally different ways during wakefulness, slow-wave sleep, and REM sleep. Analysis of beat-to-beat heart-rate variations with statistical methods enables us to estimate sleep stages based on the differences in autonomic nervous system regulation. Furthermore, up to some degree, it is possible to track transitions from wakefulness to sleep by analysis of heart-rate variations. ECG and heart rate analysis allow assessment of selected sleep disorders as well. Sleep disordered breathing can be detected reliably by studying cyclical variation of heart rate combined with respiration-modulated changes in ECG morphology (amplitude of R wave and T wave).

  17. Thermal stability of multi-longitudinal mode laser beating frequencies in hybrid semiconductor-fiber ring lasers

    Science.gov (United States)

    Shebl, Ahmed; Hassan, Khaled; Al-Arifi, Fares; Al-Otaibi, Mohammed; Sabry, Yasser; Khalil, Diaa

    2015-03-01

    The temperature dependence of the beating frequencies in multi-longitudinal mode hybrid semiconductor-fiber based ring lasers is studied theoretically and experimentally. The variation of the beating frequency with temperature is found to be smaller for larger cavity length and lower beating order. Measured frequency variation as low as -0.24 Hz/°C is obtained for cavity length of 2.7 km. The stability of the frequency is evaluated using the Allan variance technique. The measurement is carried out for different beating frequency orders. The lowest order beating frequency has about 20x better long-term frequency stability than the beating frequency of the 100th order.

  18. Cardiac arrhythmia beat classification using DOST and PSO tuned SVM.

    Science.gov (United States)

    Raj, Sandeep; Ray, Kailash Chandra; Shankar, Om

    2016-11-01

    -based assessment scheme respectively to the state-of-art diagnosis. The results reported are further compared to the existing methodologies in literature. The proposed feature representation of cardiac signals based on symmetrical features along with PSO based optimization technique for the SVM classifier reported an improved classification accuracy in both the assessment schemes evaluated on the benchmark MIT-BIH arrhythmia database and hence can be utilized for automated computer-aided diagnosis of cardiac arrhythmia beats. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. [Study of biometric identification of heart sound base on Mel-Frequency cepstrum coefficient].

    Science.gov (United States)

    Chen, Wei; Zhao, Yihua; Lei, Sheng; Zhao, Zikai; Pan, Min

    2012-12-01

    Heart sound is a physiological parameter with individual characteristics generated by heart beat. To do the individual classification and recognition, in this paper, we present our study of using wavelet transform in the signal denoising, with the Mel-Frequency cepstrum coefficients (MFCC) as the feature parameters, and propose a research of reducing the dimensionality through principal components analysis (PCA). We have done the preliminary study to test the feasibility of biometric identification method using heart sound. The results showed that under the selected experimental conditions, the system could reach a 90% recognition rate. This study can provide a reference for further research.

  20. General anesthesia suppresses normal heart rate variability in humans

    Science.gov (United States)

    Matchett, Gerald; Wood, Philip

    2014-06-01

    The human heart normally exhibits robust beat-to-beat heart rate variability (HRV). The loss of this variability is associated with pathology, including disease states such as congestive heart failure (CHF). The effect of general anesthesia on intrinsic HRV is unknown. In this prospective, observational study we enrolled 100 human subjects having elective major surgical procedures under general anesthesia. We recorded continuous heart rate data via continuous electrocardiogram before, during, and after anesthesia, and we assessed HRV of the R-R intervals. We assessed HRV using several common metrics including Detrended Fluctuation Analysis (DFA), Multifractal Analysis, and Multiscale Entropy Analysis. Each of these analyses was done in each of the four clinical phases for each study subject over the course of 24 h: Before anesthesia, during anesthesia, early recovery, and late recovery. On average, we observed a loss of variability on the aforementioned metrics that appeared to correspond to the state of general anesthesia. Following the conclusion of anesthesia, most study subjects appeared to regain their normal HRV, although this did not occur immediately. The resumption of normal HRV was especially delayed on DFA. Qualitatively, the reduction in HRV under anesthesia appears similar to the reduction in HRV observed in CHF. These observations will need to be validated in future studies, and the broader clinical implications of these observations, if any, are unknown.