WorldWideScience

Sample records for beating heart intracardiac

  1. Robotic Motion Compensation for Beating Heart Intracardiac Surgery

    OpenAIRE

    Howe, Robert D.; Yuen, Shelten G.; Kettler, Daniel T.; Notovny, Paul M.; Plowes, Richard D.

    2009-01-01

    3D ultrasound imaging has enabled minimally invasive, beating heart intracardiac procedures. However, rapid heart motion poses a serious challenge to the surgeon that is compounded by significant time delays and noise in 3D ultrasound. This paper investigates the concept of using a one-degree-of-freedom motion compensation system to synchronize with tissue motions that may be approximated by 1D motion models. We characterize the motion of the mitral valve annulus and show that it is well appr...

  2. Robotic force stabilization for beating heart intracardiac surgery.

    Science.gov (United States)

    Yuen, Shelten G; Yip, Michael C; Vasilyev, Nikolay V; Perrin, Douglas P; del Nido, Pedro J; Howe, Robert D

    2009-01-01

    The manipulation of fast moving, delicate tissues in beating heart procedures presents a considerable challenge to surgeons. We present a new robotic force stabilization system that assists surgeons by maintaining a constant contact force with the beating heart. The system incorporates a novel, miniature uniaxial force sensor that is mounted to surgical instrumentation to measure contact forces during surgical manipulation. Using this sensor in conjunction with real-time tissue motion information derived from 3D ultrasound, we show that a force controller with feed-forward motion terms can provide safe and accurate force stabilization in an in vivo contact task against the beating mitral valve annulus. This 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. PMID:20425967

  3. Effects of beating-heart and arrested heart intracardiac procedure on the inflammation induced by cardiopulmonary bypass

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhe; XIAO Ying-Bin; CHEN Lin; WANG Xue-feng; ZHONG Qian-jin

    2005-01-01

    Objective:To evaluate the effects of beating-heart and arrested heart intracardiac procedure on the expression of tumor necrosis factor alpha (TNF-α) mRNA in myocardium.Methods: Thirty congenital ventricular septal defect (VSD) patients aged from 5 to 10 years old were randomly divided into 2 groups equally. Group A underwent traditional arrested-heart intracardiac procedures; group B underwent beating-heart procedures. Specimens of myocardium were obtained at the onset (baseline) and the end of cardiopulmonary bypass (CPB) for the determination of TNF-α mRNA. Concentration of TNF-α was respectively measured after anesthetic induction (T1), 20 min after the beginning of CPB (T2), at the end of CPB (T3) and 6, 12, 24 h after CPB (T4-6) in all patients. After separating polymorphonuclear leucocyte (PMN), we distilled nuclear protein and mensurated the activation of nuclear factor-κB (NF-κB) by electrophoretic mobility shift assay (EMSA). Results:Compared with baseline, the expression of TNF-α mRNA significantly increased in both groups (P<0.05). TNF-α mRNA level of group A was significantly higher than that of group B at the end of CPB (P<0.05). The plasma concentration of TNF-α and neutrophil NF-κB activity in group A was significantly higher than that of group B at T4-6 (P<0.05). Conclusion:Compared with traditional arrested CPB, beating heart intracadiac procedure can effectively reduce the expression and release of TNF-α; it will benefit the protection of pediatric myocardial during CPB.

  4. Robotic Catheters for Beating Heart Surgery

    OpenAIRE

    Kesner, Samuel Benjamin

    2011-01-01

    Compliant and flexible cardiac catheters provide direct access to the inside of the heart via the vascular system without requiring clinicians to stop the heart or open the chest. However, the fast motion of the intracardiac structures makes it difficult to modify and repair the cardiac tissue in a controlled and safe manner. In addition, rigid robotic tools for beating heart surgery require the chest to be opened and the heart exposed, making the procedures highly invasive. The novel robot...

  5. Clinical comparison of beating-heart and arrested-heart intracardiac procedure in pediatrics%婴幼儿心脏不停跳和停跳心内直视手术的临床对比

    Institute of Scientific and Technical Information of China (English)

    吴军; 何巍; 冯旭

    2011-01-01

    Objective;To compare the effects of mild hypothermia beating-heart cardiopulmonary bypass (CPB) with those of moderate hypothermia arrested-heat CPB in pediatric intracardiac procedure. Methods;56 patients whose age were under 3 years underwent open heart surgery. They were divided to group 1, 26 patients underwent arrested-heart operation, and group 2,30 patients underwent beating-heart operations. Duration of CPB and surgery,postoperative mechanical respiratory assistance duration and incidence of low cardiac output, ect,were compared between the tow groups. Results: Duration of CPB and operative duration in group 2 were shorter than those in group 1 ( P < 0.01), and postoperative mechanical respiratory assistance duration was shorter in group 2. The incidence of low cardiac output syndrome and serious cardiac arrhythmia in group 2 was lower than those in group 1, and postoperative residential duration was shorter in group 2. Conclusion:The mild hypothermia beating-heart CPB is a safe abd effective technique applied to pediatric cardiac surgery.%目的:比较浅低温心脏不停跳和中低温停跳技术,在婴幼儿心内直视手术的应用.方法:分析56例3岁以下心脏手术患者,将其分为停跳组(组Ⅰ)26例和不停跳组(组Ⅱ)30例.比较2组患者的体外循环(CPB)时间、手术时间、术后呼吸机辅助时间、术后低心排出量综合征(低心排)发生率等指标.结果:不停跳组患者的体外循环时间和手术时间均较停跳组短(P<0.01),并且术后呼吸机辅助时间、术后住院时间较停跳组短(P<0.05);不停跳组患者术后低心排发生率和严重心律失常发生率,均较停跳组低(P<0.05).结论:表明浅低温体外循环心脏不停跳,可作为一项安全、有效的技术应用于婴幼儿先天性心脏畸形的矫治.

  6. Transseptal left heart catheterisation guided by intracardiac echocardiography

    NARCIS (Netherlands)

    T. Szili-Torok (Tamas); G-J.P. Kimman (Geert-Jan); J. Res (Jan); L.J.L.M. Jordaens (Luc); J.R.T.C. Roelandt (Jos); D.A.M.J. Theuns (Dominic)

    2001-01-01

    textabstractOBJECTIVE: To develop a novel approach of transseptal puncture guided by intracardiac echocardiography and to assess its efficacy. METHODS: Transcatheter intracardiac echocardiography with a 9 MHz rotating transducer was performed to guide transseptal puncture in 12 pat

  7. Dynamic focusing in the zebrafish beating heart

    Science.gov (United States)

    Andrés-Delgado, L.; Peralta, M.; Mercader, N.; Ripoll, J.

    2016-03-01

    Of the large amount of the animal models available for cardiac research, the zebrafish is extremely valuable due to its transparency during early stages of development. In this work a dual illumination laser sheet microscope with simultaneous dual camera imaging is used to image the beating heart at 200 fps, dynamically and selectively focusing inside the beating heart through the use of a tunable lens. This dual color dynamic focusing enables imaging with cellular resolution at unprecedented high frame rates, allowing 3D imaging of the whole beating heart of embryonic zebrafish.

  8. Heart Beat Classification Using Particle Swarm Optimization

    OpenAIRE

    Ali Khazaee

    2013-01-01

    This paper proposes a novel system to classify three types of electrocardiogram beats, namely normal beats and two manifestations of heart arrhythmia. This system includes three main modules: a feature extraction module, a classifier module, and an optimization module. In the feature extraction module, a proper set combining the shape features and timing features is proposed as the efficient characteristic of the patterns. In the classifier module, a multi-class support vector machine (SVM)-b...

  9. 4D ultrasound and 3D MRI registration of beating heart

    International Nuclear Information System (INIS)

    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.)

  10. Computer Simulation of the Beating Human Heart

    Science.gov (United States)

    Peskin, Charles S.; McQueen, David M.

    2001-06-01

    The mechanical function of the human heart couples together the fluid mechanics of blood and the soft tissue mechanics of the muscular heart walls and flexible heart valve leaflets. We discuss a unified mathematical formulation of this problem in which the soft tissue looks like a specialized part of the fluid in which additional forces are applied. This leads to a computational scheme known as the Immersed Boundary (IB) method for solving the coupled equations of motion of the whole system. The IB method is used to construct a three-dimensional Virtual Heart, including representations of all four chambers of the heart and all four valves, in addition to the large arteries and veins that connect the heart to the rest of the circulation. The chambers, valves, and vessels are all modeled as collections of elastic (and where appropriate, actively contractile) fibers immersed in viscous incompressible fluid. Results are shown as a computer-generated video animation of the beating heart.

  11. Heart Beat Classification Using Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Ali Khazaee

    2013-05-01

    Full Text Available This paper proposes a novel system to classify three types of electrocardiogram beats, namely normal beats and two manifestations of heart arrhythmia. This system includes three main modules: a feature extraction module, a classifier module, and an optimization module. In the feature extraction module, a proper set combining the shape features and timing features is proposed as the efficient characteristic of the patterns. In the classifier module, a multi-class support vector machine (SVM-based classifier is proposed. For the optimization module, a particle swarm optimization algorithm is proposed to search for the best value of the SVM parameters and upstream by looking for the best subset of features that feed the classifier. Simulation results show that the proposed algorithm has very high recognition accuracy. This high efficiency is achieved with only little features, which have been selected using particle swarm optimizer.

  12. "Keep the Beat": Healthy Blood Pressure Helps Prevent Heart Disease

    Science.gov (United States)

    ... Keep the Beat": Healthy Blood Pressure Helps Prevent Heart Disease Past Issues / Winter 2010 Table of Contents Your ... a condition that also increases the chance of heart disease and stroke. High blood pressure is especially common ...

  13. Mercury Beating Heart: Modifications to the Classical Demonstration

    Science.gov (United States)

    Najdoski, Metodija; Mirceski, Valentin; Petrusevski, Vladimir M.; Demiri, Sani

    2007-01-01

    The mercury beating heart (MBH) is a commonly performed experiment, which is based on varying oxidizing agents and substituting other metals for iron. Various modified versions of the classical demonstration of the experiment are presented.

  14. Surgical correction of ruptured aneurysms of the sinus of Valsalva using on-pump beating-heart technique

    Directory of Open Access Journals (Sweden)

    Lin Hui

    2010-05-01

    Full Text Available Abstract Background Rupture of aneurysms of the sinus of Valsalva results in abrupt onset of congestive heart failure. On-pump beating-heart surgery may reduce cardiac impairment by maintaining coronary blood flow and avoiding cardioplegia. Herein, we report the operative correction of thirty-one patients of ruptured aneurysms of the sinus of Valsalva, using the on-pump beating-heart technique. Methods Thirty-one patients with ruptured aneurysms of the sinus of Valsalva underwent operative corrections using the on-pump beating-heart technique. In patients with fistula diameter less than 1 cm and no aortic regurgitation, the aorta was unclamped throughout cardiopulmonary bypass(CPB while receiving antegrade heart perfusion. In remainder of patients, retrograde perfusion was used. Results After intracardiac manipulation was complete and the nasopharyngeal temperature was raised to 36-37°C, the patients were smoothly weaned off CPB. There were no early or late postoperative deaths. All patients were in New York Heart Association functional class I at follow-up (range, 0.5-1 year. Mild-to-moderate aortic valve regurgitation was observed in one patient. No recurrence of the left-to-right shunt from ruptured aneurysms of the sinus of Valsalva was observed. Conclusions Beating heart on pump allows adequate examination of the aortic lesion under near-physiologic conditions, allows decrease in ischemia-reperfusion injury and potentially decreases the risk of serious or fatal rhythm disturbances. On-pump beating-heart technique for repair of ruptured aneurysm of sinus of Valsalva is feasible and promising. Antegrade heart perfusion is suitable for patients with a fistula diameter

  15. [Non-heart-beating donors are ineligible].

    Science.gov (United States)

    Heide, W

    2016-02-01

    The death of the donor is a mandatory prerequisite for organ transplantation (dead donor rule) worldwide. It is a medical, legal and ethical consensus to accept the concept of brain death, as first proposed in 1968 by the ad hoc committee of the Harvard Medical School, as a certain criterion of death. In isolated cases where the diagnosis of brain death was claimed to be wrong, it could be demonstrated that the diagnostic procedure for brain death had not been correctly performed. In March 2014 a joint statement by the German neuromedical societies emphasized that 1) the diagnosis of brain death is one of the safest diagnoses in medicine if performed according to accepted medical standards and criteria and 2) the concept of non-heart-beating donors (NHBD, i. e. organ donation after an arbitrarily defined duration of circulatory and cardiac arrest) practiced in some European countries must be absolutely rejected because it implicates a high risk of diagnostic error. According to the current literature it is unclear at what time cardiac and circulatory arrest is irreversible and leads to irreversible cessation of all functions of the entire brain including the brainstem, even though clinical signs of cessation of brain functions are always found after 10 min. Furthermore, is it often an arbitrary decision to exactly define the duration of cardiac arrest if continuous echocardiographic monitoring has not been carried out from the very beginning. Last but not least there are ethical concerns against the concept of NHBD because it might influence therapeutic efforts to resuscitate a patient with cardiac arrest. Therefore, the German Medical Council (BÄK) has repeatedly rejected the concept of NHBD for organ transplantation since 1995. PMID:26830897

  16. Model for the heart beat-to-beat time series during meditation

    Science.gov (United States)

    Capurro, A.; Diambra, L.; Malta, C. P.

    2003-09-01

    We present a model for the respiratory modulation of the heart beat-to-beat interval series. The model consists of a pacemaker, that simulates the membrane potential of the sinoatrial node, modulated by a periodic input signal plus correlated noise that simulates the respiratory input. The model was used to assess the waveshape of the respiratory signals needed to reproduce in the phase space the trajectory of experimental heart beat-to-beat interval data. The data sets were recorded during meditation practices of the Chi and Kundalini Yoga techniques. Our study indicates that in the first case the respiratory signal has the shape of a smoothed square wave, and in the second case it has the shape of a smoothed triangular wave.

  17. Intracardiac echocardiography.

    Science.gov (United States)

    Bruce, C J; Friedman, P A

    2002-10-01

    This article describes currently available intracardiac ultrasound (ICE) technology contrasting it with intravascular ultrasound (IVUS) highlighting their differences. Clinical applications in the electrophysiologic and cardiac catheterization laboratory are discussed and current limitations addressed. Intracardiac echocardiography (ICE) is possible because lower frequency transducers (in contrast to higher frequency IVUS devices) have been miniaturized and mounted onto catheters capable of percutaneous insertion into the heart. These lower frequency transducers are capable of enhanced tissue penetration, permitting high-resolution 2D "whole heart" imaging. Also, with the introduction of the newest phased array transducer, Doppler hemodynamic data in addition to high resolution imaging can also be obtained. ICE facilitates electrophysiologic procedures by guiding transseptal catheterization, enabling endocardial anatomy visualization and targeting of arrhythmogenic substrate, ensuring optimal ablation electrode/tissue contact and promptly diagnosing procedural complications. Promising non-electrophysiologic applications include guidance of percutaneous closure of septal defects, percutaneous mitral balloon valvuloplasty and complex cardiac biopsy. Current limitations include monoplanar imaging, narrow field of view, and relatively large size of the catheter. Intra-cardiac imaging is now a clinical tool and has the potential to play an important role in diagnostic and therapeutic interventional procedures. Further refinement and miniaturization of these transducers, through continued technological progress, will make way for primary operator controlled, integrated ultrasound-guided interventional devices.

  18. Model for the respiratory modulation of the heart beat-to-beat time interval series

    Science.gov (United States)

    Capurro, Alberto; Diambra, Luis; Malta, C. P.

    2005-09-01

    In this study we present a model for the respiratory modulation of the heart beat-to-beat interval series. The model consists of a set of differential equations used to simulate the membrane potential of a single rabbit sinoatrial node cell, excited with a periodic input signal with added correlated noise. This signal, which simulates the input from the autonomous nervous system to the sinoatrial node, was included in the pacemaker equations as a modulation of the iNaK current pump and the potassium current iK. We focus at modeling the heart beat-to-beat time interval series from normal subjects during meditation of the Kundalini Yoga and Chi techniques. The analysis of the experimental data indicates that while the embedding of pre-meditation and control cases have a roughly circular shape, it acquires a polygonal shape during meditation, triangular for the Kundalini Yoga data and quadrangular in the case of Chi data. The model was used to assess the waveshape of the respiratory signals needed to reproduce the trajectory of the experimental data in the phase space. The embedding of the Chi data could be reproduced using a periodic signal obtained by smoothing a square wave. In the case of Kundalini Yoga data, the embedding was reproduced with a periodic signal obtained by smoothing a triangular wave having a rising branch of longer duration than the decreasing branch. Our study provides an estimation of the respiratory signal using only the heart beat-to-beat time interval series.

  19. Validation of four-dimensional ultrasound for targeting in minimally-invasive beating-heart surgery

    Science.gov (United States)

    Pace, Danielle F.; Wiles, Andrew D.; Moore, John; Wedlake, Chris; Gobbi, David G.; Peters, Terry M.

    2009-02-01

    Ultrasound is garnering significant interest as an imaging modality for surgical guidance, due to its affordability, real-time temporal resolution and ease of integration into the operating room. Minimally-invasive intracardiac surgery performed on the beating-heart prevents direct vision of the surgical target, and procedures such as mitral valve replacement and atrial septal defect closure would benefit from intraoperative ultrasound imaging. We propose that placing 4D ultrasound within an augmented reality environment, along with a patient-specific cardiac model and virtual representations of tracked surgical tools, will create a visually intuitive platform with sufficient image information to safely and accurately repair tissue within the beating heart. However, the quality of the imaging parameters, spatial calibration, temporal calibration and ECG-gating must be well characterized before any 4D ultrasound system can be used clinically to guide the treatment of moving structures. In this paper, we describe a comprehensive accuracy assessment framework that can be used to evaluate the performance of 4D ultrasound systems while imaging moving targets. We image a dynamic phantom that is comprised of a simple robot and a tracked phantom to which point-source, distance and spherical objects of known construction can be attached. We also follow our protocol to evaluate 4D ultrasound images generated in real-time by reconstructing ECG-gated 2D ultrasound images acquired from a tracked multiplanar transesophageal probe. Likewise, our evaluation framework allows any type of 4D ultrasound to be quantitatively assessed.

  20. How random is your heart beat?

    CERN Document Server

    Urbanowicz, K; Holyst, J A; Zebrowski, J J

    2006-01-01

    We measure the content of random uncorrelated noise in heart rate variability using a general method of noise level estimation using a coarse grained entropy. We show that usually - except for atrial fibrillation - the level of such noise is within 5 - 15% of the variance of the data and that the variability due to the linearly correlated processes is dominant in all cases analysed but atrial fibrillation. The nonlinear deterministic content of heart rate variability remains significant and may not be ignored.

  1. 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....

  2. 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.

  3. Evaluation of the beat-to-beat detection accuracy of PulseOn wearable optical heart rate monitor.

    Science.gov (United States)

    Parak, Jakub; Tarniceriu, Adrian; Renevey, Philippe; Bertschi, Mattia; Delgado-Gonzalo, Ricard; Korhonen, Ilkka

    2015-08-01

    Heart rate variability (HRV) provides significant information about the health status of an individual. Optical heart rate monitoring is a comfortable alternative to ECG based heart rate monitoring. However, most available optical heart rate monitoring devices do not supply beat-to-beat detection accuracy required by proper HRV analysis. We evaluate the beat-to-beat detection accuracy of a recent wrist-worn optical heart rate monitoring device, PulseOn (PO). Ten subjects (8 male and 2 female; 35.9±10.3 years old) participated in the study. HRV was recorded with PO and Firstbeat Bodyguard 2 (BG2) device, which was used as an ECG based reference. HRV was recorded during sleep. As compared to BG2, PO detected on average 99.57% of the heartbeats (0.43% of beats missed) and had 0.72% extra beat detection rate, with 5.94 ms mean absolute error (MAE) in beat-to-beat intervals (RRI) as compared to the ECG based RRI BG2. Mean RMSSD difference between PO and BG2 derived HRV was 3.1 ms. Therefore, PO provides an accurate method for long term HRV monitoring during sleep. PMID:26738173

  4. In vivo electroporation mediated gene delivery to the beating heart.

    Directory of Open Access Journals (Sweden)

    Erick L Ayuni

    Full Text Available Gene therapy may represent a promising alternative strategy for cardiac muscle regeneration. In vivo electroporation, a physical method of gene transfer, has recently evolved as an efficient method for gene transfer. In the current study, we investigated the efficiency and safety of a protocol involving in vivo electroporation for gene transfer to the beating heart. Adult male rats were anesthetised and the heart exposed through a left thoracotomy. Naked plasmid DNA was injected retrograde into the transiently occluded coronary sinus before the electric pulses were applied. Animals were sacrificed at specific time points and gene expression was detected. Results were compared to the group of animals where no electric pulses were applied. No post-procedure arrhythmia was observed. Left ventricular function was temporarily altered only in the group were high pulses were applied; CK-MB (Creatine kinase and TNT (Troponin T were also altered only in this group. Histology showed no signs of toxicity. Gene expression was highest at day one. Our results provide evidence that in vivo electroporation with an optimized protocol is a safe and effective tool for nonviral gene delivery to the beating heart. This method may be promising for clinical settings especially for perioperative gene delivery.

  5. Efficient heart beat detection using embedded system electronics

    Science.gov (United States)

    Ramasamy, Mouli; Oh, Sechang; Varadan, Vijay K.

    2014-04-01

    The present day bio-technical field concentrates on developing various types of innovative ambulatory and wearable devices to monitor several bio-physical, physio-pathological, bio-electrical and bio-potential factors to assess a human body's health condition without intruding quotidian activities. One of the most important aspects of this evolving technology is monitoring heart beat rate and electrocardiogram (ECG) from which many other subsidiary results can be derived. Conventionally, the devices and systems consumes a lot of power since the acquired signals are always processed on the receiver end. Because of this back end processing, the unprocessed raw data is transmitted resulting in usage of more power, memory and processing time. This paper proposes an innovative technique where the acquired signals are processed by a microcontroller in the front end of the module and just the processed signal is then transmitted wirelessly to the display unit. Therefore, power consumption is considerably reduced and clearer data analysis is performed within the module. This also avoids the need for the user to be educated about usage of the device and signal/system analysis, since only the number of heart beats will displayed at the user end. Additionally, the proposed concept also eradicates the other disadvantages like obtrusiveness, high power consumption and size. To demonstrate the above said factors, a commercial controller board was used to extend the monitoring method by using the saved ECG data from a computer.

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

    International Nuclear Information System (INIS)

    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)

  7. 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

    2014-01-01

    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

  8. A Quadratic Nonlinear Prediction-Based Heart Motion Model Following Control Algorithm in Robotic-Assisted Beating Heart Surgery

    OpenAIRE

    Fan Liang; Xiaofeng Meng

    2013-01-01

    Off‐pump coronary artery bypass graft surgery outperforms the traditional on‐pump surgery because the assisted robotic tools can cancel the relative motion between the beating heart and the robotic tools, which reduces post‐surgery complications for patients. The challenge for the robot assisted tool when tracking the beating heart is the abrupt change caused by the nonlinear nature of heart motion and high precision surgery requirements. A characteristic analysis of 3D heart motion data thro...

  9. Synchronization using environmental coupling in mercury beating heart oscillators

    Science.gov (United States)

    Singla, Tanu; Montoya, Fernando; Rivera, M.; Tajima, Shunsuke; Nakabayashi, Seiichiro; Parmananda, P.

    2016-06-01

    We report synchronization of Mercury Beating Heart (MBH) oscillators using the environmental coupling mechanism. This mechanism involves interaction of the oscillators with a common medium/environment such that the oscillators do not interact among themselves. In the present work, we chose a modified MBH system as the common environment. In the absence of coupling, this modified system does not exhibit self sustained oscillations. It was observed that, as a result of the coupling of the MBH oscillators with this common environment, the electrical and the mechanical activities of both the oscillators synchronized simultaneously. Experimental results indicate the emergence of both lag and the complete synchronization in the MBH oscillators. Simulations of the phase oscillators were carried out in order to better understand the experimental observations.

  10. Respiratory sinus arrhythmia during anaesthesia: assessment of respiration related beat-to-beat heart rate variability analysis methods.

    Science.gov (United States)

    Loula, P; Jäntti, V; Yli-Hankala, A

    1997-11-01

    Beat-to-beat heart rate variability analysis is a powerful tool for the diagnosis of neuropathy. Respiration-related heart rate variability (respiratory sinus arrhythmia, RSA) reflects the function of parasympathetic nervous system during spontaneous ventilation while awake. RSA is also claimed to monitor the depth of anaesthesia. Power spectrum analysis or various averaging techniques of the heart rate variability are usually applied. The current literature, however, does not usually interpret the ground rules and limitations of the method used, and this may sometimes lead to erroneous conclusions on the data. The aim of our study was to compare and analyse critically the performance of different methods of evaluating RSA during anaesthesia and positive pressure ventilation. Power spectrum analysis, the root mean square of the successive RR-interval difference (RMSSD), and two respiration related methods, RSA index and average phase RSA, were included in the comparison. To test these methods, 11 patients were anaesthetised with isoflurane and their lungs were ventilated mechanically with a frequency of 6 cycles min-1. Each patient received a bolus dose of atropine (20 micrograms kg-1) during the trial. Electrocardiogram, electroencephalogram and tracheal pressure signal from respirator were recorded and analyses were performed off-line. We demonstrated that general indices, such as RMSSD, may be strongly affected by heart rate level and other non-respiration related variations in heart rate. We also showed that the effect of unwanted fluctuations on RSA can be reduced with respiration dependent beat-to-beat methods. Furthermore we confirmed that in addition to the amplitude, also the pattern of respiratory sinus arrhythmia is of interest: the pattern is reversed in phase compared to spontaneous breathing while awake, as we have shown earlier. To analyse RSA during anaesthesia, we recommend the use of an average phase RSA method based on beat-to-beat variability

  11. Non-heart-beating organ donation in Italy.

    Science.gov (United States)

    Geraci, P M; Sepe, V

    2011-06-01

    In 2007 the non-heart-beating organ donation (NHBD) "Programma Alba" (Sunrise Programme) started in Pavia, Italy. The initial plan was to cut down waiting list for kidney transplantation, while its final aim is to shorten organ transplantation waiting lists. When compared to European countries and the USA, the Italian NHBD program has taken longer to get established. Initially Italian physicians were not entirely aware of the NHBD organ viability for transplantation, furthermore ethical issues and the need to regulate medical requirements to Italian law slowed down the NHBD program. In particular, Italian legislation provides for death ascertainment after irreversible cardiac arrest, 20-minute flat electrocardiogram. This no-touch period is longer when compared to worldwide legislation, and organ viability has been a main concern for Italian transplant doctors over the years. However, recent data let up to 40-minute warm ischemia time to preserve organ viability; this has encouraged Pavia's group to establish the NHBD "Programma Alba". It was designed according to Italian legislation from death diagnosis to graft placement, from this perspective must the significant role of the Transplant coordinator be recognized. Since 2007 seven kidneys have been gathered from seven NHBD. Of these, six NHBD kidneys have been transplanted. Currently, four patients are out of dialysis. This report is a detailed description of NHBD "Programma Alba" and its preliminary results. PMID:21617625

  12. Microwave radiation and heart-beat rate of rabbits.

    Science.gov (United States)

    Chou, C K; Han, L F; Guy, A W

    1980-06-01

    Each of three adult New Zealand rabbits, 2 male and 1 female albinos, was exposed dorsally or ventrally, to 2450-MHz plane waves for 20 min under each of several field conditions: 1) to continuous waves (CW) at 5 mW/cm2; 2) to pulsed waves (PW) of 1-microsecond width that recurred 700 pps at an average of 5 mW/cm2 and at a peak of 7.1 W/cm2; 3) to PW of 10-microseconds width at a peak of 13.7 W/cm2 that were synchronized with and triggered by the R wave of the electrocardiogram (EKG) at various delay times (0, 100, and 200 ms; and 4) to CW at 80 mW/cm2. Carbon-loaded Teflon electrodes were used to record the EKG from forelimbs of an animal before, during, and after irradiation whilst it was maintained in a constant exposure geometry in a wooden squeeze box. Field induced changes in the heart-beat rate were observed at 80 mW/cm2 but not a lower average power densities, although a peak positive chronotropic effect might have been occasioned by PM introduced at 100 and 200 ms after the R wave peak. No cumulative effect was observed over a period of four months. Thermographic analysis revealed relatively little absorption of microwave energy by the myocardium irrespective of anatomical aspect of exposure.

  13. Influence of microwaves on the beating rate of isolated rat hearts.

    Science.gov (United States)

    Yee, K C; Chou, C K; Guy, A W

    1988-01-01

    Previous reports have shown that microwave exposure can decrease the beating rate of isolated rat hearts. These experiments were conducted at room temperature and with the hearts exposed to air. We observed arrhythmia frequently at room temperature, and the variation of heart beat was so large that it makes the results difficult to reproduce. Therefore, we employed a double-circulating system to provide perfusion through the coronary artery and around the outside of the heart to maintain the rat hearts at 37.7 degrees C. No arrhythmias were observed in our experiments, and the hearts were beating for at least 1 h. The effects of 16-Hz modulated 2,450-MHz pulsed microwaves (10 microseconds, 100 pps) on the beating rate of 50 isolated rat hearts were studied. Results showed no statistically significant changes of heart rate in exposed groups at SARs of 2 and 10 W/kg compared with the control group. The effect seen at 200 W/kg was shown to be similar to that resulting from heating the heart.

  14. Race May Influence Risk for Irregular Heart Beat

    Science.gov (United States)

    ... Heart failure is a common risk factor for atrial fibrillation. Heart failure affects 5.8 million people in the United ... Services, or federal policy. More Health News on: Atrial Fibrillation Health Disparities Heart Failure Recent Health News Related MedlinePlus Health Topics Atrial ...

  15. A Quadratic Nonlinear Prediction-Based Heart Motion Model Following Control Algorithm in Robotic-Assisted Beating Heart Surgery

    Directory of Open Access Journals (Sweden)

    Fan Liang

    2013-01-01

    Full Text Available Off‐pump coronary artery bypass graft surgery outperforms the traditional on‐pump surgery because the assisted robotic tools can cancel the relative motion between the beating heart and the robotic tools, which reduces post‐surgery complications for patients. The challenge for the robot assisted tool when tracking the beating heart is the abrupt change caused by the nonlinear nature of heart motion and high precision surgery requirements. A characteristic analysis of 3D heart motion data through bi‐spectral analysis demonstrates the quadratic nonlinearity in heart motion. Therefore, it is necessary to introduce nonlinear heart motion prediction into the motion tracking control procedures. In this paper, the heart motion tracking problem is transformed into a heart motion model following problem by including the adaptive heart motion model into the controller. Moreover, the model following algorithm with the nonlinear heart motion model embedded inside provides more accurate future reference by the quadratic term of sinusoid series, which could enhance the tracking accuracy of sharp change point and approximate the motion with sufficient detail. The experiment results indicate that the proposed algorithm outperforms the linear prediction‐based model following controller in terms of tracking accuracy (root mean square.

  16. Lung Transplantation from Nonheparinized Category III Non-Heart-Beating Donors. A Single-Centre Report

    NARCIS (Netherlands)

    Erasmus, Michiel E.; Verschuuren, Erik A. M.; Nijkamp, Danielle M.; Vermeyden, J. Wytse; van der Bij, Wim

    2010-01-01

    Background. Despite the increasing use of extended lung donors, the shortage of lung donors remains. Usage of non-heart-beating (NHB) lung donors contributes to fight this shortage. We describe our experience in 21 consecutive adult lung transplantations using nonheparinized category III NHB donors

  17. Smith predictor-based robot control for ultrasound-guided teleoperated beating-heart surgery.

    Science.gov (United States)

    Bowthorpe, Meaghan; Tavakoli, Mahdi; Becher, Harald; Howe, Robert

    2014-01-01

    Performing surgery on fast-moving heart structures while the heart is freely beating is next to impossible. Nevertheless, the ability to do this would greatly benefit patients. By controlling a teleoperated robot to continuously follow the heart's motion, the heart can be made to appear stationary. The surgeon will then be able to operate on a seemingly stationary heart when in reality it is freely beating. The heart's motion is measured from ultrasound images and thus involves a non-negligible delay due to image acquisition and processing, estimated to be 150 ms that, if not compensated for, can cause the teleoperated robot's end-effector (i.e., the surgical tool) to collide with and puncture the heart. This research proposes the use of a Smith predictor to compensate for this time delay in calculating the reference position for the teleoperated robot. The results suggest that heart motion tracking is improved as the introduction of the Smith predictor significantly decreases the mean absolute error, which is the error in making the distance between the robot's end-effector and the heart follow the surgeon's motion, and the mean integrated square error.

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

    International Nuclear Information System (INIS)

    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 beats2/min2 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)

  19. Effect of myocardial protection during beating heart surgery with right sub-axiliary approach

    Institute of Scientific and Technical Information of China (English)

    MA Jie; LI Xin-hua; YAN Zi-xing; LIU Ai-jun; ZHANG Wen-kai; YANG Li-na

    2009-01-01

    Background Cardiac troponin-I (cTnl) is one of the three regulatory subunits of the cardiac troponin which has the high sensibility and specificity of responding to myocardial injury. Studies have demonstrated that cTnl is released into the blood stream within hours following acute myocardial reperfusion injury. The clinical utility of cTnl for the assessment of myocardial damage is that it is more specific than creatine kinase MB (CKMB). This study investigated cTnl as a sensitive marker of myocardial reperfusion injury and its clinical value on beating heart surgery with right sub-axiliary incision. Methods From December 2002 threugh December 2004,100 patients with atrial septal defect (ASD), ventricular septal defect (VSD), atrial septal defect and ventricular septal defect (ASD+VSD), and tetralogy of Fallot were randomly divided into two groups: the treatment group (n=50) was operated on with a beating heart under extracorporeal circulation (ECC), and the control group (n=50) on an conventional arresting heart under ECC. The two groups both used a right sub-axillary incision. Blood samples from a central venous catheter (CVC) were collected before, at the end of aortic clamping, immediately after discontinue cardiopulmonary bypass (CPB), 3, 6, 24, and 48 hours after operation. The Abbott Axsym system with hol-automation fluorescent immunity analyzer was used for the quantitative determination of cTnl. cTnl was detected to investigate the effect of myocardial ischemia reperfusion injury and the clinical value of beating heart surgery with right sub-axillary incision. Results There were no significant differences between the two groups before operation. At the end of aortic clamping and thereafter, cTnl significantly increased in both groups, and reached the peak point at 6 hours after operation. At all the tested points, cTnl was significantly higher in the control group than the beating heart group (P <0.05), especially at 6 hours post operation (P <0.01). The

  20. 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.

  1. Force control of flexible catheter robots for beating heart surgery

    OpenAIRE

    Kesner, Samuel Benjamin; Howe, Robert D.

    2011-01-01

    Recent developments in cardiac catheter technology promise to allow physicians to perform most cardiac interventions without stopping the heart or opening the chest. However, current cardiac devices, including newly developed catheter robots, are unable to accurately track and interact with the fast moving cardiac tissue without applying potentially damaging forces. This paper examines the challenges of implementing force control on a flexible robotic catheter. In particular, catheter frictio...

  2. In vitro hemodynamics and valve imaging in passive beating hearts.

    Science.gov (United States)

    Leopaldi, A M; Vismara, R; Lemma, M; Valerio, L; Cervo, M; Mangini, A; Contino, M; Redaelli, A; Antona, C; Fiore, G B

    2012-04-30

    Due to their high complexity, surgical approaches to valve repair may benefit from the use of in vitro simulators both for training and for the investigation of those measures which can lead to better clinical results. In vitro tests are intrinsically more effective when all the anatomical substructures of the valvular complexes are preserved. In this work, a mock apparatus able to house an entire explanted porcine heart and subject it to pulsatile fluid-dynamic conditions was developed, in order to enable the hemodynamic analysis of simulated surgical procedures and the imaging of the valvular structures. The mock loop's hydrodynamic design was based on an ad-hoc defined lumped-parameter model. The left ventricle of an entire swine heart was dynamically pressurized by an external computer-controlled pulse duplicator. The ascending aorta was connected to a hydraulic circuit which simulated the input impedance of the systemic circulation; a reservoir passively filled the left atrium. Accesses for endoscopic imaging were located in the apex of the left ventricle and in the aortic root. The experimental pressure and flow tracings were comparable with the typical in vivo curves; a mean flow of 3.5±0.1l pm and a mean arterial pressure of 101±2 mmHg was obtained. High-quality echographic and endoscopic video recordings demonstrated the system's excellent potential in the observation of the cardiac structures dynamics. The proposed mock loop represents a suitable in vitro system for the testing of minimally-invasive cardiovascular devices and surgical procedures for heart valve repair. PMID:22387122

  3. Dual ipsilateral renal transplantation from a non-heart-beating donor.

    OpenAIRE

    Bhatti, Aftab A.; Navarro, Alex; Gok, Mohammad A.; Wilson, Colin H.; Asher, John; Wong, Yew Toh; Hua, Mi; Talbot, David

    2005-01-01

    A case is described where both kidneys from non-heart-beating (expanded criteria) donors were dual transplanted ipsilaterally. Although both kidneys passed viability tests on the Newcastle machine preservation system and biomarkers' evaluation, there were logistical issues where the cold ischaemic time was too protracted necessitating the transplantation of both kidneys into one recipient. The recipient had satisfactory outcome with the Cockcroft-Gault creatinine clearance of 72.47 (36.29 ml/...

  4. Comparison of hemodynamic responses to dexmedetomidine versus esmolol in patients undergoing beating heart surgery

    Directory of Open Access Journals (Sweden)

    Mohamed Abdel Rahman Salem M.D,* Mostafa Elhamamsy M.D

    2001-09-01

    Full Text Available adrenergic agonists decrease sympathetic tone with ensuing attenuation of neuroendocrine and hemodynamic responses to anesthesia and surgery. Also, administration of beta -adrenergic antagonists contributes to prophylaxis against hypertension, tachycardia and myocardial ischemia and myocardial protection during cardiac surgery. The effects of dexmedetomidine (DEX, a highly specific alpha -adrenergic agonist, on these responses have not yet been fully reported in patients undergoing cardiac surgery. Esmolol (ESM is a cardioselective, short-acting -blocking agent. Previous studies have established the effectiveness of esmolol in the reduction of hemodynamic responses during anesthetic induction. Aim: The study of hemodynamic responses of dexmedetomidine and esmolol and their effects on the anesthetic requirements during anesthesia in beating heart surgery. Methods: Forty patients scheduled for elective beating heart surgery received a !thereaf"#$%!&'" end of surgery in the ESM group. Total intravenous anesthesia using fentanyl, cisatracurium a"( -* +of surgery. Hemodynamics measured included heart rate, mean arterial pressure, filling pressures, cardiac index, systemic and pulmonary vascular resistances. The incidence of hypotension, hypertension, tachycardia, bradycardia, dysrhythmias, ST segment changes, total anesthetics requirements, muscle rigidity and postoperative shivering were recorded. Results: #$%",-.&/ 0*! 0 ! l/min/m ( 1 ! + 2

  5. COMPARISON OF THE EFFECTIVENESS OF METHODS FOR BONE MARROW HARVESTING FROM NON-HEART BEATING DONORS

    Directory of Open Access Journals (Sweden)

    M. Sh. Hubutija

    2015-01-01

    Full Text Available Aim. To compare the effectiveness of different methods for bone marrow (BM harvesting from non-heart beating donors taking into account the number and the quality of collected hematopoietic stem cells (HSC. Materials and methods. The study was performed on 43 non-heart beating donors. For BM harvesting two bone marrow aspiration needles were installed in each iliac bone. The needles were installed in one bone connected to closed system, combined with surgical suction and volumetric pump. BM aspiration was performed using different values for vacuum and combining with perfusion solution into the bone. The volume, the number of nucleated cells (NC, HSC and cell viability were evaluated in the obtained samples. Results. Compared with the standard mode the usage of vacuum 0.6–0.7 atm increased the collection of NC by 65.6%, HSC 87%, and did not reduce their viability. Using a vacuum of 0.9 atm reduced the amount of collected HSC and damaged cells. While using combined aspiration and perfusion of BM HSC were prepared at more than 86.2%, but the viability of the cells was lower than under the standard aspiration. Having coherently performed a standard aspiration and aspiration with perfusion from one iliac bone 407.2 ± 46.7 ml BM, 8.0 ± 0.8 × 109  NC and 194.2 ± 20.8 × 106  HSC were harvested. The proportion of viable cells was not less than 75.2 ± 3.2%. Conclusion. Method of BM harvesting implying coherently performing aspiration and aspiration-perfusion with the usage of vacuum 0.6–0.7 atm allows to prepare more progenitor cells without losing their quality. As a result, from one non-heart beating donor different types of progenitor cells can be collected in the amount sufficient for systemic infusion in adult patient.

  6. 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....... In comparison, dogs with acute AVB had low variability (1.3 +/- 0.3 ms; n = 9; P Cardiac electrical remodeling after AVB is associated with an increase in beat-to-beat variability of repolarization. Chronic AVB dogs displaying further elevated variability of repolarization are prone...

  7. Myocardial revascularization using on-pump beating heart among patients with left ventricular dysfunction

    Directory of Open Access Journals (Sweden)

    Isleem Ismail

    2010-11-01

    Full Text Available Abstract Objectives On-pump beating heart technique for myocardial revascularization has been used successfully among both low and high risk patients. Its application among low ejection fraction patients is limited. The aim of our study is to evaluate this technique among patients with low ejection fraction and to compare results with off-pump bypass technique. Methods This retrospective study includes 137 patients with ejection fraction below 0.35 who underwent isolated coronary artery bypass surgery. 39 patients underwent myocardial revascularization using on-pump beating heart (ONCAB/BH, while 98 patients had off-pump beating heart (OPCAB. Different preoperative, operative and postoperative variables were evaluated among both groups. Results Patients profiles and risk factors were similar among both groups, except for the number of patients undergoing redo CABG which was significantly higher among ONCAB/BH (13% vs 3%; p = 0.025. Ejection fraction (EF varied from 10-34%. The mean EF for patients who underwent ONCAB/BH was 28 ± 6 in comparison to 26 ± 5 for OPCAB patients (P = 0.093. Predicted risk for surgery according to EuroSCORE was similar among both groups (P = 0.443. The number of grafts performed per patient was significantly more among patients who underwent ONCAB/BH (2.2 ± 0.7 Vs 1.7 ± 0.7; P = 0.002. Completeness of revascularization was significantly greater in the ONCAB/BH patients (72% Vs 46%, P = 0.015. The incidence of hospital mortality and combined major morbidity was more among ONCAB/BH in comparison to OPCAB, but the difference was not significant. However, the incidence of blood loss, ventricular arrythmias, inotropic support, ICU, hospital stay and blood transfusion were significantly greater among patients who underwent ONCAB/BH. Conclusions On-pump beating heart technique can be used in myocardial revascularization among patients with left ventricular dysfunction. The technique was found to be associated with better

  8. Beating Heart Mitral Valve Replacement Surgery without Aortic Cross-Clamping via Right Thoracotomy in a Patient with Compromised Left Ventricular Functions

    Directory of Open Access Journals (Sweden)

    Ahmet Baris-Durukan

    2015-10-01

    Full Text Available Global myocardial ischemia and ischemia-reperfusion injury are potential adverse events related with cardioplegic arrest. Beating heart surgery has avoided such complications and adapted to valve surgery following successful results published on myocardial revascularization. Difficulty in weaning from cardiopulmonary bypass may be lessened by using on-pump beating heart surgery for mitral valve interventions. Here we describe a 64-year-old male patient with severe mitral regurgitation and dilated cardiomyopathy. Beating heart mitral valve replacement surgery was performed without aortic cross-clamping through a right thoracotomy approach. We believe that, particularly in patients with poor left ventricular functions, beating heart mitral valve surgery may be advantageous

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

    Directory of Open Access Journals (Sweden)

    Gert Jan Pelgrim

    2015-01-01

    Full Text Available 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 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. Results. 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. Conclusion. 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. 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. PMID:26218439

  11. First in vivo traveling wave magnetic particle imaging of a beating mouse heart

    Science.gov (United States)

    Vogel, P.; Rückert, M. A.; Klauer, P.; Kullmann, W. H.; Jakob, P. M.; Behr, V. C.

    2016-09-01

    Magnetic particle imaging (MPI) is a non-invasive imaging modality for direct detection of superparamagnetic iron-oxide nanoparticles based on the nonlinear magnetization response of magnetic materials to alternating magnetic fields. This highly sensitive and rapid method allows both a quantitative and a qualitative analysis of the measured signal. Since the first publication of MPI in 2005 several different scanner concepts have been presented and in 2009 the first in vivo imaging results of a beating mouse heart were shown. However, since the field of view (FOV) of the first MPI-scanner only covers a small region several approaches and hardware enhancements were presented to overcome this issue and could increase the FOV on cost of acquisition speed. In 2014 an alternative scanner concept, the traveling wave MPI (TWMPI), was presented, which allows scanning an entire mouse-sized volume at once. In this paper the first in vivo imaging results using the TWMPI system are presented. By optimizing the trajectory the temporal resolution is sufficiently high to resolve the dynamic of a beating mouse heart.

  12. Valve Replacement Performed on the Beating Heart with Continuous Retrograde Coronary Sinus Isothermic Blood Perfusion Combined with Coronary Bypass

    Directory of Open Access Journals (Sweden)

    Orhan Saim Demirtürk

    2012-12-01

    Full Text Available An operation on the beating heart was planned for a 60-year-old woman who applied to our clinic with aortic stenosis, three vessel coronary artery disease and poor left ventricular function. There are reports about beating heart valve surgery perfomed alone or combined with coronary artery bypass operations using continuous retrograde coronary sinus isothermic blood perfusion in patients with poor ventricle. We performed a coronary revascularization process for three-vessel disease on the pump beating heart and aortic valve replacement under cross-clamp using continuous retrograde coronary sinus isothermic blood perfusion in the same session. She was discharged on the sixth postoperative day after an uneventful recovery. She is well and active 24 months after the operation. Valve replacement using the retrograde coronary sinus isothermic blood perfusion technique due to its protective effect on the already borderline myocardial functions in patients with poor ventricles is a useful and clinically successful method.

  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. An efficient method of addressing ectopic beats: new insight into data preprocessing of heart rate variability analysis

    Institute of Scientific and Technical Information of China (English)

    Feng WEN; Fang-tian HE

    2011-01-01

    Heart rate variability (HRV) analysis is affected by ectopic beats.An efficient method was proposed to deal with the ectopic beats.The method was based on trend correlation of the heart timing signal.Predictor of R-R interval (RRI) value at ectopic beat time was constructed by the weight calculation and the slope estimation of preceding normal RRI.The type of ectopic beat was detected and replaced by the predictor of RRI.The performance of the simulated signal after ectopic correction was tested by the standard value using power spectrum density (PSD) estimation,whereas the results of clinical data with ectopic beats were compared with the adjacent ectopic-free data.The result showed the frequency indexes after ectopy corrected had less error than other methods with the test of simulated signal and clinical data.It indicated our method could improve the PSD estimation in HRV analysis.The method had advantages of high accuracy and real time properties to recover the sinus node modulation.

  16. An efficient method of addressing ectopic beats: new insight into data preprocessing of heart rate variability analysis.

    Science.gov (United States)

    Wen, Feng; He, Fang-Tian

    2011-12-01

    Heart rate variability (HRV) analysis is affected by ectopic beats. An efficient method was proposed to deal with the ectopic beats. The method was based on trend correlation of the heart timing signal. Predictor of R-R interval (RRI) value at ectopic beat time was constructed by the weight calculation and the slope estimation of preceding normal RRI. The type of ectopic beat was detected and replaced by the predictor of RRI. The performance of the simulated signal after ectopic correction was tested by the standard value using power spectrum density (PSD) estimation, whereas the results of clinical data with ectopic beats were compared with the adjacent ectopic-free data. The result showed the frequency indexes after ectopy corrected had less error than other methods with the test of simulated signal and clinical data. It indicated our method could improve the PSD estimation in HRV analysis. The method had advantages of high accuracy and real time properties to recover the sinus node modulation.

  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. Simulation of the Beating Heart Based on Physically Modeling a Deformable Balloon

    International Nuclear Information System (INIS)

    The motion of the beating heart is complex and creates artifacts in SPECT and x-ray CT images. Phantoms such as the Jaszczak Dynamic Cardiac Phantom are used to simulate cardiac motion for evaluation of acquisition and data processing protocols used for cardiac imaging. Two concentric elastic membranes filled with water are connected to tubing and pump apparatus for creating fluid flow in and out of the inner volume to simulate motion of the heart. In the present report, the movement of two concentric balloons is solved numerically in order to create a computer simulation of the motion of the moving membranes in the Jaszczak Dynamic Cardiac Phantom. A system of differential equations, based on the physical properties, determine the motion. Two methods are tested for solving the system of differential equations. The results of both methods are similar providing a final shape that does not converge to a trivial circular profile. Finally, a tomographic imaging simulation is performed by acquiring static projections of the moving shape and reconstructing the result to observe motion artifacts. Two cases are taken into account: in one case each projection angle is sampled for a short time interval and the other case is sampled for a longer time interval. The longer sampling acquisition shows a clear improvement in decreasing the tomographic streaking artifacts

  19. Heart beat detection in multimodal physiological data using a hidden semi-Markov model and signal quality indices.

    Science.gov (United States)

    A F Pimentel, Marco; Santos, Mauro D; Springer, David B; Clifford, Gari D

    2015-08-01

    Accurate heart beat detection in signals acquired from intensive care unit (ICU) patients is necessary for establishing both normality and detecting abnormal events. Detection is normally performed by analysing the electrocardiogram (ECG) signal, and alarms are triggered when parameters derived from this signal exceed preset or variable thresholds. However, due to noisy and missing data, these alarms are frequently deemed to be false positives, and therefore ignored by clinical staff. The fusion of features derived from other signals, such as the arterial blood pressure (ABP) or the photoplethysmogram (PPG), has the potential to reduce such false alarms. In order to leverage the highly correlated temporal nature of the physiological signals, a hidden semi-Markov model (HSMM) approach, which uses the intra- and inter-beat depolarization interval, was designed to detect heart beats in such data. Features based on the wavelet transform, signal gradient and signal quality indices were extracted from the ECG and ABP waveforms for use in the HSMM framework. The presented method achieved an overall score of 89.13% on the hidden/test data set provided by the Physionet/Computing in Cardiology Challenge 2014: Robust Detection of Heart Beats in Multimodal Data. PMID:26218536

  20. Assessment of the interface of beating heart with total artificial heart using magnetic resonance imaging

    International Nuclear Information System (INIS)

    We have studied three-dimensionally (3-D) reconstructed images of atrioventricular (AV) annuli based on four-chamber magnetic resonance (MR) images for total artificial heart (TAH) implantation. To assess the interrelationship among the AV annuli and the thorax, we applied the frame of reference of the vertebral canal to these images. The Z-axis was along the vertebral canal, the Y-axis in the anteroposterior direction. The angle alpha was defined as the angle between the X-axis and the intersection between the plane of the annulus and the X-Y plane. The angle beta was defined as the angle between the Z-axis and the intersection between the plane of annulus and X-Z plane. The angle gamma was defined as the angle between the plane of the annulus and the anterior thoracic wall. We determined each angle for the mitral annulus (MVA) and tricuspid annulus (TVA) in four normal subjects to be as follows: alpha-MVA, 20.5-39.5 degrees; alpha-TVA, 26.1-43.5 degrees; beta-MVA, 4.7-49.4 degrees; beta-TVA, 4.4-40.9 degrees; and gamma-TVA, 35.2-44.1 degrees. It is suggested that reconstruction of the thoracic wall and AV annuli using the frame of reference of the diaphragmatic surface of the heart would facilitate evaluation of the spacial requirements for TAH implantation. Research to define this new frame of reference is in progress. (author)

  1. Intracardiac Thrombosis in Sickle Cell Disease

    OpenAIRE

    Marzieh Nikparvar; Mohammad Reza Evazi; Tasnim Eftekhari; Farzaneh Moosavi

    2016-01-01

    In patients with sickle cell disease, thrombotic microangiopathy is a rare complication. Also in sickle cell disease, intracardiac thrombus formation without structural heart diseases or atrial arrhythmias is a rare phenomenon. We herein describe a 22-year-old woman, who was a known case of sickle cell-βthalassemia, had a history of recent missed abortion, and was admitted with a vaso-occlusive crisis. The patient had manifestations of microangiopathic hemolytic anemia, including laboratory e...

  2. Beating heart on a chip: a novel microfluidic platform to generate functional 3D cardiac microtissues.

    Science.gov (United States)

    Marsano, Anna; Conficconi, Chiara; Lemme, Marta; Occhetta, Paola; Gaudiello, Emanuele; Votta, Emiliano; Cerino, Giulia; Redaelli, Alberto; Rasponi, Marco

    2016-02-01

    In the past few years, microfluidic-based technology has developed microscale models recapitulating key physical and biological cues typical of the native myocardium. However, the application of controlled physiological uniaxial cyclic strains on a defined three-dimension cellular environment is not yet possible. Two-dimension mechanical stimulation was particularly investigated, neglecting the complex three-dimensional cell-cell and cell-matrix interactions. For this purpose, we developed a heart-on-a-chip platform, which recapitulates the physiologic mechanical environment experienced by cells in the native myocardium. The device includes an array of hanging posts to confine cell-laden gels, and a pneumatic actuation system to induce homogeneous uniaxial cyclic strains to the 3D cell constructs during culture. The device was used to generate mature and highly functional micro-engineered cardiac tissues (μECTs), from both neonatal rat and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM), strongly suggesting the robustness of our engineered cardiac micro-niche. Our results demonstrated that the cyclic strain was effectively highly uniaxial and uniformly transferred to cells in culture. As compared to control, stimulated μECTs showed superior cardiac differentiation, as well as electrical and mechanical coupling, owing to a remarkable increase in junction complexes. Mechanical stimulation also promoted early spontaneous synchronous beating and better contractile capability in response to electric pacing. Pacing analyses of hiPSC-CM constructs upon controlled administration of isoprenaline showed further promising applications of our platform in drug discovery, delivery and toxicology fields. The proposed heart-on-a-chip device represents a relevant step forward in the field, providing a standard functional three-dimensional cardiac model to possibly predict signs of hypertrophic changes in cardiac phenotype by mechanical and biochemical co-stimulation.

  3. Beating heart on a chip: a novel microfluidic platform to generate functional 3D cardiac microtissues.

    Science.gov (United States)

    Marsano, Anna; Conficconi, Chiara; Lemme, Marta; Occhetta, Paola; Gaudiello, Emanuele; Votta, Emiliano; Cerino, Giulia; Redaelli, Alberto; Rasponi, Marco

    2016-02-01

    In the past few years, microfluidic-based technology has developed microscale models recapitulating key physical and biological cues typical of the native myocardium. However, the application of controlled physiological uniaxial cyclic strains on a defined three-dimension cellular environment is not yet possible. Two-dimension mechanical stimulation was particularly investigated, neglecting the complex three-dimensional cell-cell and cell-matrix interactions. For this purpose, we developed a heart-on-a-chip platform, which recapitulates the physiologic mechanical environment experienced by cells in the native myocardium. The device includes an array of hanging posts to confine cell-laden gels, and a pneumatic actuation system to induce homogeneous uniaxial cyclic strains to the 3D cell constructs during culture. The device was used to generate mature and highly functional micro-engineered cardiac tissues (μECTs), from both neonatal rat and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM), strongly suggesting the robustness of our engineered cardiac micro-niche. Our results demonstrated that the cyclic strain was effectively highly uniaxial and uniformly transferred to cells in culture. As compared to control, stimulated μECTs showed superior cardiac differentiation, as well as electrical and mechanical coupling, owing to a remarkable increase in junction complexes. Mechanical stimulation also promoted early spontaneous synchronous beating and better contractile capability in response to electric pacing. Pacing analyses of hiPSC-CM constructs upon controlled administration of isoprenaline showed further promising applications of our platform in drug discovery, delivery and toxicology fields. The proposed heart-on-a-chip device represents a relevant step forward in the field, providing a standard functional three-dimensional cardiac model to possibly predict signs of hypertrophic changes in cardiac phenotype by mechanical and biochemical co

  4. A Successful Transplantation from Maastricht Category-4 Non-Heart Beating Donor

    Directory of Open Access Journals (Sweden)

    Veysi BAHADIR

    2015-09-01

    Full Text Available The shortage of available organs is the limiting factor for kidney transplantation (Ktx. One of the strategies to increase access to Ktx is the use of non-heart beating (NHB donors. We herein present a successful Ktx from an NHB (Maastricht Category-4 donor. The donor was a 21-year-old woman who had brain death due to cerebrovascular accident. She had severe hypotension for three hours despite 30 μg/kg/min dopamine infusion, followed by cardio-pulmonary arrest just before the operation began. Cardio-pulmonary resuscitation was consequently initiated and continued during the operation. Donor organ harvesting (hepatectomy and bilateral nephrectomy was performed after direct aortic cannulation. The warm ischemia time was 35 minutes. The recipient was a 54-year-old man who had undergone hemodialysis for four years. There were 3/6 mismatches, and the lymphocyte cross-match was negative. The induction immunosuppressive was anti-thymocyte globulin, followed by tacrolimus/ MMF/steroid after the 12th day. He had delayed graft function and hemodialysis was required at the third and sixth days. The urine output gradually increased and sCr slowly declined afterwards and he discharged with sCr 1.5 mg/dl on the 24th day. At the first year of transplantation, he is in good clinical condition with a stable baseline sCr of 1.5 mg/dl. NHB donors can be an alternative and important source to expand the kidney donation pool, and successful long-term outcomes favor this modality.

  5. Experience of valve replacement under mild hypothermia on pump-beating heart:an analysis of 800 cases

    Institute of Scientific and Technical Information of China (English)

    陈柏成; 肖颖彬; 陈林; 钟前进; 王学锋; 周骐; 易广兵

    2004-01-01

    Objective: To assess the outcome of valve replacement under mild hypothermia on pump-beating heart and to discuss the risk factors of cardiac valve surgery. Methods: In the period from November 1997 to May 2003, a total of 800cases of valve replacement were carried out in our institute. The clinical data were reviewed and the technique of mild hypothermia and pump-beating heart to replace cardiac valve was described in detail. Results: 800 patients, 308 male and 492female, with age range from 8 to 66 years, weighing 19 to 88 kg, underwent operation. The average cardiopulmonary bypass time was (109.38 ± 40.64) min, the average clamping time of the vena cava was (77.87 ± 27.99) min and the average mechanical ventilation time was (17.78 ± 12.21) h. There were 17 patients died in the early postoperative stage with an early mortality rate of 2.13%. The causes of death were failure in the weaning of extracorporeal circulation in 2 cases, severe low output syndrome in 3 cases, ventricular fibrillation in 3 cases, obstruction of coronary ostium of mechanical prosthetic valve in 1 case, hepatic failure in 2 cases, pulmonary failure in 1 case, multiorgan failure in 4 cases, and prosthetic valve dysfunction in 1 case. Severe postopertive complications occurred in 51 cases (6.375%), which included reexploration because of excessive bleeding in 16 cases (2.0%), lavage of poststemal infection in 2 cases (0.25%), postoperative strike in 7 cases (0.875%), pulmonary failure in 5 cases (0.625%), hepatic failure in 4 cases (0.5%), multiorgan failure in 11 cases (1.375 % ), ventricular arrhythmia in 5 cases (0.625%) and peripheral circulation failure in 1 case(0. 125 % ). Conclusion: Mild hypothermia and pump-beating heart result in satisfying clinical outcome in patients undergoing valve replacement. The integrated sequenced deairing procedure ensures the avoidance of air embolism during operation.Pump-beating heart technique offers a safe and practical option especially in

  6. Detecting variations of blood volume shift due to heart beat from respiratory inductive plethysmography measurements in man

    International Nuclear Information System (INIS)

    The simultaneous study of the cardiac and respiratory activities and their interactions is of great physiological and clinical interest. For this purpose, we want to investigate if respiratory inductive plethysmography (RIP) can be used for cardiac functional exploration. We propose a system, based on RIP technology and time-scale approaches of signal processing, for the extraction of cardiac information. This study focuses on the monitoring of blood volume shift due to heart beat, noted ▵Vtrc and investigates RIP for the detection of ▵Vtrc variations by comparison to stroke volume (SV) variations estimated by impedance cardiography (IMP). We proposed a specific respiratory protocol assumed to induce significant variations of the SV. Fifteen healthy volunteers in the seated and supine positions were asked to alternate rest respiration and maneuvers, consisting in blowing into a manometer. A multi-step treatment including a variant of empirical mode decomposition was applied on RIP signals to extract cardiac volume signals and estimate beat-to-beat ▵Vtrc. These were averaged in quasi-stationary states at rest and during the respiratory maneuvers, and analysed in view of SV estimations from IMP signals simultaneously acquired. Correlation and statistical tests over the data show that RIP can be used to detect variations of the cardiac blood shift in healthy young subjects. (paper)

  7. Comparison of plasma NSE, protein S-100b and EEG changes in traditional arrested-heart procedures and on-pump beating-heart procedures

    Institute of Scientific and Technical Information of China (English)

    王咏; 肖颖彬; 陈林; 王学锋; 钟前进

    2003-01-01

    Objective: To assess the cerebral injury in on-pump beating-heart procedures under mild hypothermia in comparison with traditional on-pump arrested-heart procedures under moderate hypothermia. Methods: Forty patients, 20 with congenital heart disease (CHD) and 20 of rheumatic heart disease (RHD), were divided into 2 groups: Control group (group A, n=20) including 10 patients suffering from CHD as group A1 and the left 10 from RHD as group A2; and experiment group (group B, n=20) which consisting of group B1 (10 with CHD) and group B2 (10 of RHD). The patients in group A underwent traditional arrested-heart procedures, and those in group B were operated on with beating-heart procedures. Arterial blood samples were collected at preoperation (time A), 20 min after cardiopulmonary bypass (CPB) starting (time B), 1 h after CPB (time C) and 24 h postoperation (time D) respectively. Plasma contents of neuron-specific enolase (NSE) and protein S-100b were measured with sensitive ELISA. All the patients received echoencephalography (EEG) before and 1 week after operation. Results: The plasma contents of protein S-100b were increased very significantly at time B, C and D in comparison with those at time A (P<0.01), and that of patients in group A1 was significantly higher than that in group B at time B (P<0.05). There was no significant difference at other time points. At time B, the plasma contents of NSE were significantly higher in group A than in group B, and in group A1 and B1 than in group A2 and B2. What's more, at time B, the former fell back to their preoperative levels, but the latter remained still higher levels than the preoperative ones (P<0.01). No significant difference was found in the abnormality rates of postoperative EEG between 2 groups. Conclusion: The perioperative plasma contents of NSE and protein S-100b are not significantly higher in group B than in group A. On-pump beating-heart procedures do not make more serious cerebral dysfunction than the

  8. The effects of exercise training on maximum aerobic capacity, rest heart beat, blood pressure and anthropometric variables of postmenopausal women with breast cancer

    Directory of Open Access Journals (Sweden)

    Nader - Rahnama

    2010-01-01

    Full Text Available ABSTRACT. The aim of this study was to investigate the effects of exercise training on maximum aerobic capacity, rest heart beat, blood pressure and anthropometric variables of postmenopausal women with breast cancer. Twenty nine women with breast cancer who received surgery, chemotherapy and radiotherapy with current hormone therapy divided into two groups; intervention and control. Subjects of intervention group performed 15 weeks combination exercise training including walking (2 sessions per week and resistance training (2 sessions per week that different from walking days. Before and after 15 weeks, Vo2max, rest heart beat, blood pressure, body weight, body mass index (BMI and waist to hip ratio (WHR were measured in two groups. Data analyzed by using t- test. Significant differences were observed for Vo2max, rest heart beat, body weight, BMI and WHR between intervention and control groups (P< 0.05, after 15 weeks. In fact, exercise training had positive effects on the Vo2max, rest heart beat, body weight, BMI and WHR in postmenopausal women with breast cancer. No significant different was founded for blood pressure between two groups (P=0.193. In conclusion, exercise training can improve maximum aerobic capacity, rest heart beat and anthropometric variables in postmenopausal women with breast cancer.

  9. Organ bath in detecting the effect of one-hour warm ischemia on pulmonic arteries and bronchi from non-heart-beating donor lungs

    Institute of Scientific and Technical Information of China (English)

    ZHAO Song; WANG Jia-xiang; YANG Yang; HE Zhan-feng; LIAO Qiu-ming

    2009-01-01

    Background Non-heart-beating donor lung has been a promising source of lung transplantation. Many studies on non-heart-beating donor lungs are based on animal lung transplantation. In this study, we assessed by organ bath the effect of one-hour warm ischemia on the non-heart-beating donor lung in terms of the integrity of contractile and relaxant functions and tissue structures of pulmonic arteries and bronchi.Methods Sixteen Swedish pigs were randomly classified into two groups: heart-beating donor group and 1-hour warm ischemia non-heart-beating donor group. Pulmonic and bronchial rings were taken from the isolated left lungs of the pigs. The pulmonic rings were stimulated by U-46619 (5.7 mol/L) and acetylcholine (10~(-4) mmol/L) to assess the contractile abilities of smooth muscle and the endothelium-dependent relaxation response, respectively. As such, acetylcholine (10~(-5) mmol/L) and natrium arachidonic acid (0.01%) were used to detect the contraction of bronchial smooth muscle and epithelium-dependent relaxation response. Meanwhile, the variances of precontraction tension of control groups were recorded to measure whether there was spontaneous relaxation during endothelium/epithelium-dependent relaxation course. Finally, papaverine solution (10~(-4) mmol/L) was used to detect the non-endothelium/epithelium-dependent relaxant abilities of pulmonic and bronchial smooth muscles.Results There was no significant difference in the tension values of precontraction of pulmonic rings (P>0.05), endothelium-dependent relaxation (P>0.05), precontraction of bronchial rings (P>0.05) and epithelium-dependent relaxation (P>0.05) between the heart-beating donor group and the 1-hour warm ischemia non-heart-beating donor group. And the pulmonic and bronchial rings of each subgroup B had no spontaneous relaxation. Finally, papaverine solution relaxed the smooth muscle of all the rings completely.Conclusions The results of this experiment suggest that the contractile

  10. Longitudinal changes in intracardiac repolarization lability in patients with implantable cardioverter-defibrillator

    Directory of Open Access Journals (Sweden)

    Abhilash eGuduru

    2013-08-01

    Full Text Available Background─While it is known that elevated baseline intracardiac repolarization lability is associated with the risk of fast ventricular tachycardia (FVT /ventricular fibrillation (VF, the effect of its longitudinal changes on the risk of FVT/VF is unknown. Methods and Results─Near-field (NF right ventricular (RV intracardiac electrograms (EGMs were recorded every 3-6 months at rest in 248 patients with structural heart disease (mean age 61.2±13.3; 185[75%] male; 162[65.3%] ischemic cardiomyopathy and implanted cardioverter-defibrillator (ICD or cardiac resynchronization therapy defibrillator (CRT-D [201 (81% primary prevention]. Intracardiac beat-to-beat QT variability index (QTVINF was measured on NF RV EGM. During the first study phase (median 18 months, participants made on average 2.4 visits. Then remote follow-up was continued for an additional median period of 3 years. Average QTVINF did not change during the first year after ICD implantation (-0.342±0.603 at baseline vs. -0.262±0.552 at 6 months vs. -0.334±0.603 at 12 months; however, it decreased thereafter (-0.510±0.603 at 18 months; P=0.042. Adjusted population-averaged GEE model showed that the odds of developing FVT/VF increased by 75% for each 1 unit increase in QTVINF. (OR 1.75 [95%CI 1.05-2.92]; P=0.031. However, individual patient–specific QTVINF trends (increasing, decreasing, flat varied from patient to patient. For a given patient, the odds of developing FVT/VF were not associated with increasing or decreasing QTVINF over time (OR 1.27; [95%CI 0.05–30.10]; P = 0.881.Conclusion─While on average the odds of FVT/VF increased with an increase in QTVINF, patient-specific longitudinal trends in QTVINF did not affect the odds of FVT/VF.

  11. Sleep and wake phase of heart beat dynamics by artificial insymmetrised patterns

    Science.gov (United States)

    Dudkowska, A.; Makowiec, D.

    2004-05-01

    In order to determine differences between healthy patients and patients with congestive heart failure we apply the artificial insymmetrised pattern (AIP) method. The AIP method by exploring a human eye ability to extract regularities and read symmetries in a dot pattern, serves a tool for qualitative discrimination of heart rate states.

  12. "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…

  13. 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 pa

  14. Normothermic ex vivo lung perfusion of non-heart-beating donor lungs in pigs : from pretransplant function analysis towards a 6-h machine preservation

    NARCIS (Netherlands)

    Erasmus, ME; Fernhout, MH; Elstrodt, JM; Rakhorst, G

    2006-01-01

    Donor shortage urges optimal use of all lungs available. Ex vivo lung perfusion (EVLP) is a method to evaluate lung function before implantation. EVLP was performed in pigs to evaluate lung function, using two different clinical non-heart-beating (NHS) donor protocols: flush perfusion and topical co

  15. 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.

  16. Microwave Doppler Radar for Heart Beat Detection Versus Electrocardiogram: A Validation Approach

    OpenAIRE

    Obeid, Dany; Sadek, Sawsan; Zaharia, Gheorghe,; El Zein, Ghais

    2013-01-01

    International audience This paper provides a validation approach for a microwave Doppler Radar system used for heartbeat detection. The proposed system is tested at 16 GHz with several transmitted power, simultaneously with a pc-based electrocardiogram. Obtained results show accurate detection for the heartbeat signal in terms of heartbeat rate and heart rate variability.

  17. 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.

  18. 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. PMID:25570435

  19. 猪不停跳心脏离体模型的建立%Establishment of a porcine beating heart model in vitro

    Institute of Scientific and Technical Information of China (English)

    郑民; 宋剑非; 杨峰; 张文斌

    2011-01-01

    背景:保持供心离体跳动,可以减少供心的缺血时间,延长供心的离体保存时间.目的:建立稳定简便的猪不停跳心脏离体模型.方法:12只健康家猪随机等分为不停跳组和冷晶体灌注组.不停跳组经升主动脉建立冠状动脉灌注,经右心房进右心室建立静脉引流,经左心耳放置软管入左心室引流,建立猪的不停跳心脏离体模型.冷晶体灌注组按常规心脏移植实行心脏离体保护.结果与结论:不停跳组共施行6例猪心脏离体手术,术后2,4 h离体心脏不停跳成功率为100%(6/6),6 h离体心脏不停跳成功率为83%(5/6).与对照组相比,不停跳组丙二醛水平降低,超氧化物歧化酶活性升高(P < 0.05),心肌超微结构保持良好.说明猪的不停跳心脏离体模型成功率高,是研究离体不停跳心脏仪器的稳定可靠动物模型.%BACKGROUND: Keeping beating of the donor heart can reduce its ischemia time and prolong its preservation time in vitro. OBJECTIVE: To establish a simple and stable model of porcine beating heart in vitro.METHODS: Twelve healthy pigs were randomly divided into beating group and cold crystalloid perfusion group. In the beating group, coronary perfusion was established through the ascending aorta, venous drainage was established through right atrium into the right ventricle, the hose was placed into the left ventricle through the left atrial appendage for drainage, and then the model of porcine beating heart in vitro was established. Heart protection in vitro was performed in the cold crystalloid perfusion group after normal heart transplantation.RESULTS AND CONCLUSION: Surgery in vitro of porcine heart was successfully performed on six pigs of the beati ng group. The success rate of beating heart was 100% after 2 and 4 hours of surgery, and was 83% at 6 hours. The malondialdehyde levels were decreased, superoxide dismutase activities were increased (P < 0.05), and the myocardial ultrastructure was well

  20. Heart beat classification from single-lead ECG using the Synchrosqueezing Transform

    OpenAIRE

    Herry, Christophe L; Frasch, Martin; Seely, Andrew JE; Wu, Hau-Tieng

    2015-01-01

    The processing of ECG signal provides a wealth of information on cardiac function and overall cardiovascular health. While multi-lead ECG recordings are often necessary for a proper assessment of cardiac rhythms, they are not always available or practical, for example in fetal ECG applications. Moreover, a wide range of small non-obtrusive single-lead ECG ambulatory monitoring devices are now available, from which heart rate variability (HRV) and other health-related metrics are derived. Prop...

  1. Multiscale analysis of heart beat interval increment series and its clinical significance

    Institute of Scientific and Technical Information of China (English)

    HUANG XiaoLin; NING XinBao; WANG XinLong

    2009-01-01

    Analysis of multiscale entropy (MSE) and multiscale standard deviation (MSD) are performed for both the heart rate interval series and the interval increment series. For the interval series, it is found that, it is impractical to discriminate the diseases of atrial fibrillation (AF) and congestive heart failure (CHF) unambiguously from the healthy. A clear discrimination from the healthy, both young and old, however, can be made in the MSE analysis of the increment series where we find that both CHF and AF sufferers have significantly low MSE values in the whole range of time scales investigated, which reveals that there are common dynamic characteristics underlying these two different diseases. In addition, we propose the sample entropy (SE) corresponding to time scale factor 4 of increment series as a diag-nosis index of both AF and CHF, and the reference threshold is recommended. Further indication that this index can help discriminate sensitively the mild heart failure (cardiac function classes 1 and 2) from the healthy gives a clue to early clinic diagnosis of CHF.

  2. Effect of Pressure on Intracardiac Backscatter from Microbubbles

    Institute of Scientific and Technical Information of China (English)

    DENG; Youbin; LI; Chunlei; CHANG; Qing

    2001-01-01

    The backscatter from sonicated albumin microbubbles (Albunex) was analyzed using acoustic densitometry in an in vitro pulsatile heart model to evaluate the effects of pressure on the backscatter from Albunex, and the cardiac cyclic changes of intracardiac backscatter from sonicated albumin microbubbles in 16 healthy persons were analyzed. It was found that the Albunex microbubbles were compressed in systole and decompressed in diastole, causing corresponding changes of backscatter in cardiac cycle. Although the intensities of backscatter in diastole and systole were related to the concentration of microbubbles, the concentration of microbubbles had no effect on the difference of end-diastolic and end-systolic backscatter. The difference of the backscatter was highly correlated with end-systolic pressure (r = 0. 96, P = 0. 001). In human studies, we also observed same intracardiac cyclic changes of backscatter from sonicated albumin microbubbles. Our study indicates that it is possible to evaluate the intracardiac pressure non-invasively by analyzing the intracardiac backscatter from the microbubbles with acoustic densitometry.

  3. Electrophysiological evidence of P2X2 receptor expression in the neurons of intracardiac and paratracheal ganglia

    Institute of Scientific and Technical Information of China (English)

    MA Bei; NI Xin; HAN Hong; BURNSTOCK Geoffrey

    2006-01-01

    Objective:To investigate the expression of P2X receptors on rat intracardiac and paratracheal ganglion neurons. Methods: For preparation of intracardiac neurons, hearts were excised, the atria were separated and the medial region containing intracardiac ganglia was isolated and cut into pieces. For preparation of paratracheal neurons, the tracheas were removed and the superficial membranous layer containing paratracheal ganglia was rapidly isolated. Intracardiac and paratracheal ganglion neurons were dissociated after digestion by collagenase and trypsin. Whole-cell patch clamp recording was used to identify the pharmacological properties of P2X receptors in cultured neurons. Results:Neurons from these two ganglia responded to ATP with a rapidly activating, sustained inward current. Αβ-meATP failed to evoke any responses in paratracheal ganglion neurons while a few of intracardiac ganglion neurons responded to αβ-meATP with a tiny sustained inward current. ADP and UTP had no effect on intracardiac neurons. Lowering pH potentiated ATP responses in neurons from these two ganglia whereas increasing pH inhibited ATP responses. Co-application of Zn2+ potentiated ATP responses in intracardiac and paratracheal ganglion neurons. Conclusion: The receptor subtypes involved in intracardiac and paratracheal ganglia appear to be homomeric P2X2, while heteromeric P2X2/3 could not be completely excluded from intracardiac neurons.

  4. Beat-to-Beat Blood Pressure Monitor

    Science.gov (United States)

    Lee, Yong Jin

    2012-01-01

    This device provides non-invasive beat-to-beat blood pressure measurements and can be worn over the upper arm for prolonged durations. Phase and waveform analyses are performed on filtered proximal and distal photoplethysmographic (PPG) waveforms obtained from the brachial artery. The phase analysis is used primarily for the computation of the mean arterial pressure, while the waveform analysis is used primarily to obtain the pulse pressure. Real-time compliance estimate is used to refine both the mean arterial and pulse pressures to provide the beat-to-beat blood pressure measurement. This wearable physiological monitor can be used to continuously observe the beat-to-beat blood pressure (B3P). It can be used to monitor the effect of prolonged exposures to reduced gravitational environments and the effectiveness of various countermeasures. A number of researchers have used pulse wave velocity (PWV) of blood in the arteries to infer the beat-to-beat blood pressure. There has been documentation of relative success, but a device that is able to provide the required accuracy and repeatability has not yet been developed. It has been demonstrated that an accurate and repeatable blood pressure measurement can be obtained by measuring the phase change (e.g., phase velocity), amplitude change, and distortion of the PPG waveforms along the brachial artery. The approach is based on comparing the full PPG waveform between two points along the artery rather than measuring the time-of-flight. Minimizing the measurement separation and confining the measurement area to a single, well-defined artery allows the waveform to retain the general shape between the two measurement points. This allows signal processing of waveforms to determine the phase and amplitude changes. Photoplethysmography, which measures changes in arterial blood volume, is commonly used to obtain heart rate and blood oxygen saturation. The digitized PPG signals are used as inputs into the beat-to-beat blood

  5. [THEORETICAL BACKGROUND OF FINDING ORGANS FOR TRANSPLANTATION AMONG NON-HEART BEATING DONORS UNDER UNSUCCESSFUL EXTRACORPOREAL RESUSCITATION (LITERATURE REVIEW)].

    Science.gov (United States)

    Khodeli, N; Chkhaidze, Z; Partsakhashvili, D; Pilishvili, O; Kordzaia, D

    2016-05-01

    The number of patients who are in the "Transplant Waiting List" is increasing each year. At the same time, as a result of the significant shortage of donor organs, part of the patients dies without waiting till surgery. According to the Maastricht classification for non-heart beating donors, the patients, who had cardiac arrest outside the hospital (in the uncontrolled by medical staff conditions) should be considered as a potential donors of category II. For these patients, the most effective resuscitation is recommended. The extracorporeal life support (ECLS) considers the connection to a special artificial perfusion system for the restoration of blood circulation out-of-hospital with further transportation to the hospital. If restoration of independent cardiac activity does not occur, in spite of the full range of resuscitative measures, these patients may be regarded as potential donors. The final decision should be received in the hospital, by the council of physicians, lawyers and patient's family members. Until the final decision, the prolongation of ECLS and maintaining adequate systemic and organic circulation is recommended.

  6. Comparison of HTK and hypertonic citrate to intraarterial cooling in human non-heart-beating kidney donors.

    Science.gov (United States)

    Wilson, C H; Asher, J F; Gupta, A; Vijayanand, D; Wyrley-Birch, H; Stamp, S; Rix, D A; Soomro, N; Manas, D M; Jaques, B C; Peaston, R; Talbot, D

    2007-03-01

    Intraarterial cooling (IAC) of non-heart-beating donors (NHBD) for renal donation requires a cheap, low-viscosity solution. HTK contains a high hydrogen ion buffer level that theoretically should reduce the observable acidosis associated with ongoing anaerobic metabolism. A retrospective comparison of all retrieved NHBD kidneys as well as of viability on the Organ Recovery Systems Lifeporter machine perfusion circuit was performed with respect to the preservation solution HTK or Marshall's HOC. Forty-two NHBD kidneys (19 HTK and 23 HOC) were machine perfused between February 2004 and May 2005. Most of the HTK kidneys were obtained from uncontrolled donors (12 vs 5; Fisher exact test, P = .01). As a consequence, the glutathione-s-transferase viability assay (411 vs 292 IU/L, P = .12) and the lactate concentrations (2.33 vs 1.94 mmol/L, P = .13) were higher among the HTK cohort. There was evidence of greater buffering capacity in HTK, since the lactate:hydrogen ion ratios were consistently lower during the first 2 perfusion hours (1 hour P = .03, 2 hour P = .02). A linear regression analysis confirmed that this was related to the IAC solution (ANCOVA, P advantages of improved pH buffering with HTK appear to have clinical relevance. PMID:17362727

  7. Energy harvesting from the beating heart by a mass imbalance oscillation generator.

    Science.gov (United States)

    Zurbuchen, A; Pfenniger, A; Stahel, A; Stoeck, C T; Vandenberghe, S; Koch, V M; Vogel, Rolf

    2013-01-01

    Energy-harvesting devices attract wide interest as power supplies of today's medical implants. Their long lifetime will spare patients from repeated surgical interventions. They also offer the opportunity to further miniaturize existing implants such as pacemakers, defibrillators or recorders of bio signals. A mass imbalance oscillation generator, which consists of a clockwork from a commercially available automatic wrist watch, was used as energy harvesting device to convert the kinetic energy from the cardiac wall motion to electrical energy. An MRI-based motion analysis of the left ventricle revealed basal regions to be energetically most favorable for the rotating unbalance of our harvester. A mathematical model was developed as a tool for optimizing the device's configuration. The model was validated by an in vitro experiment where an arm robot accelerated the harvesting device by reproducing the cardiac motion. Furthermore, in an in vivo experiment, the device was affixed onto a sheep heart for 1 h. The generated power in both experiments-in vitro (30 μW) and in vivo (16.7 μW)-is sufficient to power modern pacemakers. PMID:22805983

  8. Ultrasound-Guided Transesophageal High-Intensity Focused Ultrasound Cardiac Ablation in a Beating Heart: A Pilot Feasibility Study in Pigs.

    Science.gov (United States)

    Bessiere, Francis; N'djin, W Apoutou; Colas, Elodie Constanciel; Chavrier, Françoise; Greillier, Paul; Chapelon, Jean Yves; Chevalier, Philippe; Lafon, Cyril

    2016-08-01

    Catheter ablation for the treatment of arrhythmia is associated with significant complications and often-repeated procedures. Consequently, a less invasive and more efficient technique is required. Because high-intensity focused ultrasound (HIFU) enables the generation of precise thermal ablations in deep-seated tissues without harming the tissues in the propagation path, it has the potential to be used as a new ablation technique. A system capable of delivering HIFU into the heart by a transesophageal route using ultrasound (US) imaging guidance was developed and tested in vivo in six male pigs. HIFU exposures were performed on atria and ventricles. At the time of autopsy, visual inspection identified thermal lesions in the targeted areas in three of the animals. These lesions were confirmed by histologic analysis (mean size: 5.5 mm(2) × 11 mm(2)). No esophageal thermal injury was observed. One animal presented with bradycardia due to an atrio-ventricular block, which provides real-time confirmation of an interaction between HIFU and the electrical circuits of the heart. Thus, US-guided HIFU has the potential to minimally invasively create myocardial lesions without an intra-cardiac device. PMID:27158083

  9. Ex Vivo Rehabilitation of Non-Heart-Beating Donor Lungs in a 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.

    2012-01-01

    Objectives 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 potential for rehabilitation of donor lungs with extended warm-ischemic times is unknown. This study compares the efficacy of different treatment strategies for uncontrolled non-heart-beating donor lungs. Methods Mature swine underwent hypoxic arrest followed by 60 minutes of no-touch warm-ischemia. Lungs were harvested and flushed with 4°C Perfadex®. Three groups (n=5/group) were stratified according to preservation method: cold-static preservation (CSP: 4 hrs 4°C storage), immediate EVLP (I-EVLP: 4 hrs EVLP at 37°C), and delayed EVLP (D-EVLP: 4 hrs cold storage followed by 4 hrs EVLP). EVLP groups were perfused with Steen solution™ supplemented with heparin, methylprednisolone, cefazolin, and an adenosine 2A receptor agonist. Lungs then underwent allotransplantation and four hours of recipient reperfusion prior to allograft assessment for resultant ischemia-reperfusion injury. Results Donor blood oxygenation (PO2:FiO2) prior to euthanasia was not different between groups. Oxygenation after transplantation was significantly higher in the D-EVLP group compared to the I-EVLP or CSP groups. Mean airway pressure, pulmonary artery pressure, and expression of IL-8, IL-1β, and TNF-α were all significantly reduced in the D-EVLP group. Importantly, post-transplant oxygenation exceeded acceptable clinical levels only in D-EVLP lungs. Conclusions Uncontrolled non-heart-beating donor lungs with extended warm-ischemia can be reconditioned for successful transplantation. The combination of CSP and EVLP present in the D-EVLP group was necessary to obtain optimal post-transplant function. This finding, if confirmed clinically, will allow expanded use of non-heart-beating donor lungs. PMID:22944084

  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. Levoatriocardinal vein with normal intracardiac anatomy and pulmonary venous return

    Directory of Open Access Journals (Sweden)

    Ender Odemis

    2011-01-01

    Full Text Available Levoatriocardinal vein (LACV is characterized by an abnormal connection between pulmonary and systemic venous return. This extremely rare cardiac malformation is usually associated with left-sided obstructive lesions including mitral atresia, hypoplastic left-heart syndrome, and abnormal pulmonary venous connection. Patients may have low systemic cardiac output and pulmonary venous obstruction symptoms. In this manuscript, we report a case with LACV and normal pulmonary venous return with absence of any intracardiac pathology. LACV was demonstrated with echocardiography, angiography, and computed tomography. Surgical correction was made successfully.

  12. Levoatriocardinal vein with normal intracardiac anatomy and pulmonary venous return

    International Nuclear Information System (INIS)

    Levoatriocardinal vein (LACV) is characterized by an abnormal connection between pulmonary and systemic venous return. This extremely rare cardiac malformation is usually associated with left-sided obstructive lesions including mitral atresia, hypoplastic left-heart syndrome, and abnormal pulmonary venous connection. Patients may have low systemic cardiac output and pulmonary venous obstruction symptoms. In this manuscript, we report a case with LACV and normal pulmonary venous return with absence of any intracardiac pathology. LACV was demonstrated with echocardiography, angiography, and computed tomography. Surgical correction was made successfully

  13. 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

  14. 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.

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

    OpenAIRE

    Kondratiev V.A.; Porokhnya N.H.; Kunak Ye.V.

    2013-01-01

    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...

  16. End of life care in the operating room for non-heart-beating donors: organization at the University Hospital of Liège.

    Science.gov (United States)

    Joris, J; Kaba, A; Lauwick, S; Lamy, M; Brichant, J-F; Damas, P; Ledoux, D; Damas, F; Lambermont, B; Morimont, P; Devos, P; Delbouille, M-H; Monard, J; Hans, M-F; DeRoover, A; Honoré, P; Squifflet, J-P; Meurisse, M; Detry, O

    2011-11-01

    Non-heart-beating (NHB) organ donation has become an alternative source to increase organ supply for transplantation. A NHB donation program was implemented in our institution in 2002. As in many institutions the end of life care of the NHB donor (NHBD) is terminated in the operating room (OR) to reduce warm ischemia time. Herein we have described the organization of end of life care for these patients in our institution, including the problems addressed, the solution proposed, and the remaining issues. Emphasis is given to our protocol elaborated with the different contributors of the chain of the NHB donation program. This protocol specifies the information mandatory in the medical records, the end of life care procedure, the determination of death, and the issue of organ preservation measures before NHBD death. The persisting malaise associated with NHB donation reported by OR nurses is finally documented using an anonymous questionnaire. PMID:22099816

  17. Electron-conformational transformations in nanoscopic RyR channels govern both the heart's contraction and beating

    CERN Document Server

    Moskvin, A S; Solovyova, O E; Markhasin, V S

    2011-01-01

    We show that a simple biophysically based electron-conformational model of RyR channel is able to explain and describe on equal footing the oscillatory regime of the heart's cell release unit both in sinoatrial node (pacemaker) cells under normal physiological conditions and in ventricular myocytes under Ca$^{2+}$ SR overload.

  18. A System for 3D Ultrasound-Guided Robotic Retrieval of Foreign Bodies from a Beating Heart

    NARCIS (Netherlands)

    Thienphrapa, P.; Ramachandran, B.; Taylor, R.H.T.; Popovic, A.

    2012-01-01

    By way of the venous system or direct penetration, particles such asthrombi, bullet fragments, and shrapnel can become trapped in the heart and disrupt cardiac function. The severity of disruption can range from asymptomatic to fatal. Injuries of this nature are common in both civilian and military

  19. Intracardiac metastasis from non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Vivek eVerma

    2015-07-01

    Full Text Available A 56-year-old female with history of stage IIA adenosquamous lung carcinoma treated 13 months prior to presentation with lobectomy, mediastinal lymph node dissection, and adjuvant chemotherapy, presented for several weeks of worsening dyspnea. Exam was nonfocal aside from tachycardia. Computed tomography of the chest revealed a large 4 cm x 5 cm mass in the bilateral ventricular myocardium. There was also evidence of metastatic disease elsewhere in the body, including a supraclavicular lymph node that was positive for metastatic adenosquamous lung carcinoma. She started whole heart radiotherapy and was to commence chemotherapy but passed away. This report discusses important aspects of diagnosis of this not uncommon condition that many oncologists may come across. We also discuss differential diagnosis of an isolated intracardiac mass as first-diagnosis presentations, and discuss the great importance of multidisciplinary cardio-oncologic management and clinical prioritization.

  20. 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.

  1. 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?...

  2. 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, ...

  3. High Blood Pressure: Keep the Beat Recipes

    Science.gov (United States)

    ... this page please turn Javascript on. Feature: High Blood Pressure Keep the Beat Recipes Past Issues / Fall 2011 ... National Heart, Lung, and Blood Institute To Improve Blood Pressure, Try the DASH Diet If you're one ...

  4. Heart Disease

    Science.gov (United States)

    ... occurs when the heart is not able to pump blood through the body as well as it should. ... arteries. The pressure is highest when your heart pumps blood into your arteries – when it beats. It is ...

  5. Dynamical changing patterns of histological structure and ultrastructure of liver graft undergoing warm ischemia injury from non-heart-beating donor in rats

    Institute of Scientific and Technical Information of China (English)

    Yi Ma; Guo-Dong Wang; Lin-Wei Wu; Rui-De Hu

    2006-01-01

    AIM: To investigate the histological and ultra-structural characteristics of liver graft during different of warm ischemia time (WIT) in rats and to predict the maximum limitation of liver graft to warm ischemia. METHODS: The rats were randomized into 7 groups undergoing warm ischemia injury for 0, 10, 15, 20, 30,45 and 60 min, respectively. All specimens having undergone warm ischemia injury were investigated dynamically by light and electron microscopy, and histochemistry staining. After orthotopic liver transplantation (OLT), the recovery of morphology of liver grafts after 6, 24 and 48 h was observed. RESULTS: The donor liver from non-heart-beating donors (NHBD) underwent ischemia injury both in the warm ischemia period and in the reperfusion period. Morphological changes were positively related to warm ischemia injury in a time-dependent manner during the reperfusion period. The results demonstrated that different degrees of histocyte degeneration were observed when WIT was within 30 min, and became more severe with the prolongation of WIT, no obvious hepatocyte necrosis was noted in any specimen. In the group undergolng warm ischemia injury for 45 min, small focal necrosis occurred in the central area of hepatic lobule first. In the group undergoing warm ischemia injury for 60 min, patchy or diffused necrosis was observed and the area was gradually extended, while hepatic sinusoid endothe lial cells were obviously swollen. Hepatic sinusoid was obstructed and microcirculation was in disorder. CONCLUSION: The rat liver graft undergoing warm ischemia injury is in the reversible stage when the WIT is within 30 min. The 45 min WIT may be a critical point of rat liver graft to endure warm ischemia injury. When the WIT is over 60 min, the damage is irreversible.

  6. Management of cardiopulmonary bypass for open heart surgery with beating heart%心脏跳动下心内直视手术的体外循环管理

    Institute of Scientific and Technical Information of China (English)

    杨宗英; 马瑞彦; 肖颖彬; 刘梅; 彭莉; 胡卫

    2011-01-01

    Objective To discuss the management melhods of cardiopulmonary bypass ( CPB) for palienls underwent open heart surgery with healing heart. Methods The CPB management melhods for 2 290 palienls underwenl open heart surgery with healing heart were summed-up. The left heart venling was established during the surgery and inlegraled sequelial de-airing procedure was conducted al the end of the surgery. The temperalure of nasopharynx was mainlained between 30 ~32 ℃, hemalocril was kept between 20% ~30% and the flow was controlled belween 2.4 ~3. 2 L·m-1· min-2 . Α-stat blood gas strategies were applied, meanwhile conventional ullrafilltration or modified ul-trafillralion was performed according to the condition. Results CPB went sucessful in all cases, the CPB time was 22 ~ 179 minules. Ventricular fibrillation was occurred in 256 cases and 181 cases experienced automatic recovery to healing. There were 22 cases died including 15 cases of complex congenital heart disease and 7 cases of severe valvular heart disease. No complication correlated wilh perfusion was oberved. Conclusion Open heart sugery wilh beating heart under mild hypothermia by cardiopulmonary bypass is safe and feasible, meanwhile it is easy for management and il can effectively prevenl ischemia reperfusion injury.%目的 探讨心脏跳动下心内直视手术中体外循环的管理方法.方法 总结分析2 290例心脏跳动下行心内直视手术的体外循环管理方法.术中均常规建立左心引流,术毕采用综合序贯排气技术.转流中鼻咽温维持在30~32 ℃,红细胞压积维持在20%~30%,流量控制在2.4~3.2 L·m-1·min-2,采用α稳态血气管理方法,术中酌情行常规超滤或改良超滤.结果 全组体外循环均顺利停机,转流时间22~179 min.术中室颤256例,其中181例自动复跳.全组死亡22例,其中复杂先天性心脏病15例,重症瓣膜病7例.全组无体外循环气栓并发症.结论 浅低温体外循环方法在心脏跳动

  7. Intracardiac Thrombosis during Adult Liver Transplantation

    Directory of Open Access Journals (Sweden)

    Marina Moguilevitch

    2013-01-01

    Full Text Available Intracardiac thrombosis (ICT and pulmonary embolism (PE during adult liver transplantation are rare but potentially lethal complications. They are often overlooked because of significant diagnostic challenges. The combination of hemodynamic compromise and transesophageal echocardiography (TEE findings allows for correct diagnosis. A large variety of putative risk factors for ICT and PE have been suggested, but these events are considered to be multifactorial. There are different proposed treatment modalities for these devastating complications. Unfortunately, in spite of growing knowledge in this area, intraoperative and postoperative mortalities remain very high. The retrospective nature of the study of these events makes the case reports extremely valuable.

  8. 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...

  9. Optimists May Beat Heart Disease

    Institute of Scientific and Technical Information of China (English)

    马贵根

    2001-01-01

    心脏病是美国人的最大杀手,三分之一的美国人死于此疾。乐观对健康有益,本文对“乐观”的诠释却另辟蹊径:with a sunny(本义:阳光充足的) outlook(观点;简洁)on life/power of positive thinking。对生活抱“乐呵呵”的态度,同时又具有积极乐观思维者患心脏病或其他疾病的可能性大大降低!

  10. Protective effects of L-arginine against ischemia-reper fusion injur y in non-heart beating rat liver graft

    Institute of Scientific and Technical Information of China (English)

    Jin Gong; Xue-Jun Lao; Shui-Jun Zhang; Shi Chen

    2008-01-01

    BACKGROUND: Although the use of non-heart beating donors (NHBDs) could bridge the widening gap between organ demand and supply, its application to liver transplantation is limited due to the high incidence of primary graft loss. Prevention of liver injury in NHBDs will beneift the results of transplantation. This study was conducted to evaluate the protective effects of L-arginine on liver grafts from NHBDs. METHODS: One hundred and four Wistar rats were randomly divided into 7 groups: normal control (n=8), controls 1, 2 and 3 (C1, C2, C3, n=16), and experimental 1, 2 and 3 (E1, E2, E3, n=16). For groups C1 and E1, C2 and E2, and C3 and E3, the warm ischemia time was 0, 30, and 45 minutes, respectively. Liver grafts were lfushed with and preserved in 4 ℃ Euro-collins solution containing 1 mmol/L L-arginine for 1 hour in each experimental group. Recipients of each experimental group were injected with L-arginine (10 mg/kg body weight) by tail vein 10 minutes before portal vein reperfusion. Donors and recipients of each experimental control group were treated with normal saline. Then transplantation was performed. At 1, 3, and 24 hours after portal vein reperfusion, blood samples were obtained to determine the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), nitric oxide (NO) and plasma endothelin (ET). At 3 hours after portal vein reperfusion, grafts samples were ifxed in 2.5%glutaraldehyde for electron microscopic observation. RESULTS: At 1 hour after portal vein reperfusion, the levels of NO in groups E1, E2, E3 and C1, C2, C3 were lower, while the levels of plasma ET, serum ALT and AST were higher than those in the normal control group (P CONCLUSIONS: The imbalance between NO and ET plays an important role in the development of ischemia-reperfusion injury of liver grafts from NHBDs. L-arginine can attenuate injury in liver grafts from NHBDs by improving the balance between NO and ET.

  11. 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.

  12. 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.

  13. About Heart Attacks

    Science.gov (United States)

    ... heart muscle can impact how well the heart pumps blood throughout the body. The degree of loss of ... chambers suddenly start beating chaotically and don't pump blood. Death occurs within minutes after the heart stops. ...

  14. 艾司洛尔对不停跳心内直视手术心肌的保护作用%Protective effect of esmolol on the myocardium during open heart beating surgery

    Institute of Scientific and Technical Information of China (English)

    龚倩; 葛建军; 葛圣林; 林敏; 周汝元; 高晴云

    2012-01-01

    目的 探讨β1受体阻滞剂艾司洛尔在不停跳心内直视手术中对心肌的保护作用.方法 选择22例择期行房间隔修补手术患者,随机分为两组,每组11例,两组均在常温体外循环心脏不停跳心内直视下进行房间隔修补手术.实验组在体外循环开始前于预冲液中加入艾司洛尔1 mg/kg,转机过程中再以300 μg·kg-1·min-1的速度从静脉持续输注艾司洛尔,直到手术完成.对照组给予等量的生理盐水代替艾司洛尔,其余和实验组相同.监测两组病例在各个时间点的血流动力学、血气分析、心肌损伤标志物及围手术期各项临床指标,并进行对比.结果 在转机过程中,实验组心率(56±8)次/min显著低于对照组(64±9)次/min(P<0.05),实验组cTnI和CK-MB在术后6、12、24 h各个时间点均显著低于对照组(均为P<0.001),两组病例在手术开始前、转机开始前、转机过程中、停机后和手术结束后各个时间点的血气分析指标差异无统计学意义(均为P>0.05).结论 在常温体外循环心脏不停跳心内直视手术中应用艾司洛尔可以显著保护心肌并改善手术操作条件.%Objective To investigate the cardiac protective effect of esmolol during open heart beating surgery. Methods Twenty-two patients with atrial septal defect ( ASD ) undergoing elective open heart beating surgery were randomly divided into two groups. Each group had 11 patients. Experimental group received open heart beating surgery with normothermia cardiopulmonary bypass ( CPB ). Esmolol was added into the cardioplegic solution with 1 mg·kg-1 , and then esmolol was continuous infusion intravenously with 300 μg · kg-1·min-1 during CPB until the end of surgery. Control group received saline instead of esmolol. The hemodynamics, blood gas analysis and cardiac injury markers of different time and clinical parameters of peri-operative period were recorded and compared. Results The heart rate ( HR ) during

  15. 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

  16. Comparative study of myocardial protection in cardiac arrest and beating heart surgery%心脏停跳与不停跳手术心肌保护的临床对比研究

    Institute of Scientific and Technical Information of China (English)

    王建堂; 马增山; 董铭峰; 马胜军

    2013-01-01

    目的 评价心脏停跳与不停跳手术对先天性心脏病患者的心肌保护效果.方法 房间隔缺损(ASD)、室间隔缺损(VSD)、肺动脉瓣狭窄(PS)患者共116例,随机分为实验组(不停跳组)和对照组(停跳组).实验组在体外循环(CPB)心脏跳动状态下手术,对照组在CPB心脏停跳下手术,分别于术前及术后2、6、24、48 h采集血标本,检测血清肌酸激酶同工酶(CK-MB)、肌钙蛋白Ⅰ(cTnⅠ)、天冬氨酸氨基转移酶(AST)、乳酸脱氢酶(LDH)含量;记录CPB时间、术后48 h心律失常发生率、残余分流发生率、呼吸机支持时间、ICU滞留时间、术后住院天数.结果 两组术后各时点血清CK-MB、cTnⅠ、AST、LDH含量均显著高于术前(P<0.01),但两组间各时点比较差异无统计学意义(P>0.05);实验组CPB时间较对照组短(P<0.01),其他临床观察指标与对照组比较差异无统计学意义(P>0.05).结论 体外循环心脏不停跳心内直视手术能缩短CPB时间,但手术效果与停跳手术比较差异无统计学意义.%Objective To evaluate the protective effects of cardiac arrest and beating heart on patients with congenital heart disease (CHD).Methods One hundred and sixteen CHD patients were randomly divided into experimental group (beating heart group) and control group (cardioplegia group).The experimental group received surgery on beating heart with cardiopulmonary bypass (CPB),cardiac arrest operation under CPB in the control group,respectively.Blood samples were taken and the serum levels of creatine kinase MB (CK-MB),troponin Ⅰ(cTnⅠ),aspartate aminotransferase (AST),lactate dehydrogenase (LDH) were detected before operation and 2,6,24,48 hours after operation.The clinical parameters including CPB times,incidence of arrhythmia,residual shunt occurred rate,duration of mechanical ventilation,ICU stay time and postoperative hospital stay were detected respectively.Results Postoperatively,the CK

  17. Beat-to-Beat Blood Pressure Monitor

    Science.gov (United States)

    Lee, Yong Jin

    2012-01-01

    This device provides non-invasive beat-to-beat blood pressure measurements and can be worn over the upper arm for prolonged durations. Phase and waveform analyses are performed on filtered proximal and distal photoplethysmographic (PPG) waveforms obtained from the brachial artery. The phase analysis is used primarily for the computation of the mean arterial pressure, while the waveform analysis is used primarily to obtain the pulse pressure. Real-time compliance estimate is used to refine both the mean arterial and pulse pressures to provide the beat-to-beat blood pressure measurement. This wearable physiological monitor can be used to continuously observe the beat-to-beat blood pressure (B3P). It can be used to monitor the effect of prolonged exposures to reduced gravitational environments and the effectiveness of various countermeasures. A number of researchers have used pulse wave velocity (PWV) of blood in the arteries to infer the beat-to-beat blood pressure. There has been documentation of relative success, but a device that is able to provide the required accuracy and repeatability has not yet been developed. It has been demonstrated that an accurate and repeatable blood pressure measurement can be obtained by measuring the phase change (e.g., phase velocity), amplitude change, and distortion of the PPG waveforms along the brachial artery. The approach is based on comparing the full PPG waveform between two points along the artery rather than measuring the time-of-flight. Minimizing the measurement separation and confining the measurement area to a single, well-defined artery allows the waveform to retain the general shape between the two measurement points. This allows signal processing of waveforms to determine the phase and amplitude changes.

  18. 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

  19. Cardiac beat-to-beat alternations driven by unusual spiral waves

    OpenAIRE

    Kim, Tae Yun; Woo, Sung-Jae; Hwang, Seong-min; Hong, Jin Hee; Lee, Kyoung J.

    2007-01-01

    Alternans, a beat-to-beat temporal alternation in the sequence of heartbeats, is a known precursor of the development of cardiac fibrillation, leading to sudden cardiac death. The equally important precursor of cardiac arrhythmias is the rotating spiral wave of electro-mechanical activity, or reentry, on the heart tissue. Here, we show that these two seemingly different phenomena can have a remarkable relationship. In well controlled in vitro tissue cultures, isotropic populations of rat vent...

  20. Minimally invasive robotic coronary bypass on the beating heart using da Vinci S system%机器人非体外循环冠状动脉旁路移植术

    Institute of Scientific and Technical Information of China (English)

    高长青; 杨明; 王刚; 吴扬; 赵悦; 李丽霞; 王加利; 肖苍松; 周琪

    2009-01-01

    Objective To summarize the experience of minimally invasive robotic caronary bypass on beating heart using da Vinci S in China. Methods Fifty-six patients underwent selected robotic coronary bypass on beating heart from April 2007 to December 2008. All the patients had history of angina and the coronary arteriography showed severe stenosis in the left anterior descending artery (LAD), of which 10 cases had right coronary artery or left circumflex coronary (LCX) stenosis. The age was 33 to 74 years old, with a mean of (55.8±9. 4) years old. The weight was (71.4 ± 13.2) kg, All the patients had good lung function and had no medical history of pleurisy and thoracic surgery. CT scan of double internal thoracic artery (ITA) was routinely checked preoperatively. The procedures included : (1) The robotically assisted endoscopic atranmatic coronary artery bypass surgery. The approach was via a small left anterior thoracotomy (6 to 8 cm) after robotic ITA was taken down. The ITA was manually anastomosed to the LAD or LCX on beating heart. (2) Totally endoscopic coronary bypass graft on beating heart. After ITA harvesting, the endostabilizer was inserted via the fourth pert in the xiphoid area under endoscopic vision. The left ITA to the LAD grafting was done using U-clips on beating heart in a totally endoscopic manner using da Vinci S system through 4 ports. For all patients the ITA flow was checked by the Doppler flowmeter after anastomosis was completed. After the surgery was completed, the thoracic port was checked carefully to avoid bleeding, The operating procedures and a variety of clinical parameters were recorded and analyzed. (3) Stent placement after robotic surgery in a hybrid manner. The graft pateney rate was evaluated by CT or orteriography. Results All patients successfully accepted robotic minimally invasive coronary bypass on the beating heart using da Vinci S surgical system without complications. The mean graft flow was (23.2 ± 16. 7) mL/min. And

  1. Heart bypass surgery

    Science.gov (United States)

    Off-pump coronary artery bypass; OPCAB; Beating heart surgery; Bypass surgery - heart; CABG; Coronary artery bypass graft; Coronary artery bypass surgery; Coronary bypass surgery; Coronary artery disease - CABG; CAD - CABG; Angina - ...

  2. Intracardiac Leakage of Cement During Kyphoplasty and Vertebroplasty: A Case Report

    Science.gov (United States)

    Audat, Ziad A.; Alfawareh, Mohammad D.; Darwish, Fayeq T.; Alomari, Ali A.

    2016-01-01

    Patient: Male, 28 Final Diagnosis: Intracardial cortoss leak Symptoms: Back pain Medication: — Clinical Procedure: Kyphoplasty Specialty: Orthopedics and Traumatology Objective: Diagnostic/therapeutic accidents Background: Intracardiac leakage of bone cement after kyphoplasty and vertebroplasty is a rare and life-threatening complication. Cortoss, which is an injectable, non-absorbable, polymer composite that is designed to mimic cortical bone, can be used instead of cement. Here, we present the case of a patient with right intra-cardiac Cortoss embolization. Case Report: A 28-year-old man known to have ulcerative colitis since the age of 15 and treated with corticosteroids for more than 4 years and with anti-immune drugs presented to our hospital complaining of back pain and decreased body height due to osteomalacia with failed conservative treatment. Kyphoplasty and vertebroplasty of the thoracic 10–12 and first lumbar vertebrae were done with any complications. Three months later, the patient underwent kyphoplasty and vertebroplasty of lumbar 2–5 vertebrae by injecting Cortoss instead of cement, which was complicated with paravertebral intravascular leakage. We stopped surgery and transferred him to the recovery room, where he had slight chest pain that resolved spontaneously without neurological deficit. Two days later he developed severe chest pain and chest X-ray showed a large white shadow at the right side of the heart and another 2 small shadows just lateral to it. Sudden deterioration of patient status necessitated an emergency echocardiogram, which showed pericardial tamponade and a perforated right ventricle. Aspiration of pericardial blood and emergency open heart surgery were done. He was discharged 4 days later and was followed up at an outpatient clinic. Conclusions: Cardiac embolism is a serious condition that can complicate vertebral kyphoplasty; it requires a high level of suspicion and immediate action, and may need open heart surgery to

  3. Relationship between ischemic area of coronary heart disease and origin part of ventricular premature beat%冠心病缺血区与室性早搏起源部位之间的关系

    Institute of Scientific and Technical Information of China (English)

    宋红艳; 刘相丽; 许纲

    2012-01-01

    目的 探讨冠心病与室性心律失常的关系.方法 对行冠脉造影并行Holter检查者根据造影结果分成阴性组和阳性组,以冠状动脉狭窄大于或等于70%者为阳性.分析两组Holter结果,主要是分析其室性心律失常数量、形态,记录年龄、性别、高血压史、糖尿病史、心脏彩超及室早治疗方法等.结果 冠心病室性心律失常合并高血压、糖尿病者多于特发性室性早搏,室早消融比例及室早次数多于特发性室早(P<0.05).结论 冠心病室早患者有自身的特点,对其治疗有一定指导意义.%Objective To investigate the relationship between ventricular arrhythmias and coronary heart disease(CHD). Methods The patients who underwent coronary angigraphy(CAG) and Holter were enrolled in the study. All patients were divided into negative and positive groups according to the results of CAG. The stenosis of coronary artery≥70% was positive. The Holter results, age,sex, history of hypertension and diabetes mellitus(DM) ,echocardiographic examination, therapeutic measures were analyzed in the two groups. Results The CHD patients with ventricular arrhythmias complicating hypertension and DM were more than those with idiopatic ventricular premature beat, so did the ratio of catheter ablation and the frequency of ventricular premature beat(P<0. 05). Conclusion The CHD patients complicating ventricular premature beats have own characteristics, which has some guidance significance to choose therapy.

  4. 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...

  5. Time-domain analysis of beat-to-beat variability of repolarization morphology in patients with ischemic cardiomyopathy.

    Science.gov (United States)

    Burattini, L; Zareba, W

    1999-01-01

    There is growing evidence that beat-to-beat changes in ventricular repolarization contribute to increased vulnerability to ventricular arrhythmias. Beat-to-beat repolarization variability is usually measured in the electrocardiogram (ECG) by tracking consecutive QT or RT intervals. However, these measurements strongly depend on the accurate identification of T-wave endpoints, and they do not reflect changes in repolarization morphology. In this article, we propose a new computerized time-domain method to measure beat-to-beat variability of repolarization morphology without the need to identify T-wave endpoints. The repolarization correlation index (RCI) is computed for each beat to determine the difference between the morphology of repolarization within a heart-rate dependent repolarization window compared to a template (median) repolarization morphology. The repolarization variability index (RVI) describes the mean value of repolarization correlation in a studied ECG recording. To validate our method, we analyzed repolarization variability in 128-beat segments from Holter ECG recordings of 42 ischemic cardiomyopathy (ICM) patients compared to 36 healthy subjects. The ICM patients had significantly higher values of RVI than healthy subjects (in lead X: 0.045 +/- 0.035 vs. 0.024 +/- 0.010, respectively; P 0.044). No significant correlation was found between the RVI values and the magnitude of heart rate, heart rate variability, QTc interval duration, or ejection fraction in studied ICM patients. In conclusion, our time-domain method, based on computation of repolarization correlation indices for consecutive beats, provides a new approach to quantify beat-to-beat variability of repolarization morphology without the need to identify T-wave endpoints. PMID:10688321

  6. Complex radiation diagnosis of associated intracardiac abnormality

    International Nuclear Information System (INIS)

    It is shown that patients with congenital heart diseases having signs of cardiodismorphic complex in form of associated intercardiac abnormalities require special attention after surgical correction of the principal defect. It is connected with the fact that the associated abnormalities may become with time the basic factors influencing the progress and forecast of the disease

  7. 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.

  8. Towards real-time 3D US-CT registration on the beating heart for guidance of minimally invasive cardiac interventions

    Science.gov (United States)

    Li, Feng; Lang, Pencilla; Rajchl, Martin; Chen, Elvis C. S.; Guiraudon, Gerard; Peters, Terry M.

    2012-02-01

    Compared to conventional open-heart surgeries, minimally invasive cardiac interventions cause less trauma and sideeffects to patients. However, the direct view of surgical targets and tools is usually not available in minimally invasive procedures, which makes image-guided navigation systems essential. The choice of imaging modalities used in the navigation systems must consider the capability of imaging soft tissues, spatial and temporal resolution, compatibility and flexibility in the OR, and financial cost. In this paper, we propose a new means of guidance for minimally invasive cardiac interventions using 3D real-time ultrasound images to show the intra-operative heart motion together with preoperative CT image(s) employed to demonstrate high-quality 3D anatomical context. We also develop a method to register intra-operative ultrasound and pre-operative CT images in close to real-time. The registration method has two stages. In the first, anatomical features are segmented from the first frame of ultrasound images and the CT image(s). A feature based registration is used to align those features. The result of this is used as an initialization in the second stage, in which a mutual information based registration is used to register every ultrasound frame to the CT image(s). A GPU based implementation is used to accelerate the registration.

  9. Progress of Anesthetic Management of Robotic Totally Endoscopic Coronary Artery Bypass on Beating Heart%全机器人不停跳冠状动脉旁路移植术的麻醉管理进展

    Institute of Scientific and Technical Information of China (English)

    姚优修(综述); 孟秀丽(审校)

    2015-01-01

    [Summary] Robotic totally endoscopic coronary artery bypass on beating heart (BH-TECAB), a minimally invasive surgical approach with rapid postoperative recovery , is becoming the future trend of minimally invasive coronary surgery , which demands a higher standard for anesthetic management . It comprises pressured pneumothorax , unilateral lung ventilation , transesophageal echocardiography monitoring , hemodynamics maintaining , preparation for cardiopulmonary bypass and conversion to sternotomy , and ventricular fibrillation treatment , which require anesthesiologists to achieve more refined perioperative management and pathophysiological regulation .%全机器人不停跳冠状动脉旁路移植术创伤小,术后恢复快,是未来微创冠状动脉外科的趋势,对麻醉管理提出更高的要求,主要包括加压CO2气胸、单肺通气的应用、经食道超声心动图的监测、术中血流动力学的维持、体外循环及中转开胸手术的准备、室颤的处理等,要求麻醉医师对患者病理生理的调控及围术期的管理达到更精细化。

  10. Effect of meditation on scaling behavior and complexity of human heart rate variability

    CERN Document Server

    Sarkar, A

    2006-01-01

    The heart beat data recorded from samples before and during meditation are analyzed using two different scaling analysis methods. These analyses revealed that mediation severely affects the long range correlation of heart beat of a normal heart. Moreover, it is found that meditation induces periodic behavior in the heart beat. The complexity of the heart rate variability is quantified using multiscale entropy analysis and recurrence analysis. The complexity of the heart beat during mediation is found to be more.

  11. Clinical application of low energy intracardiac cardioversion of atrial fibrillation

    International Nuclear Information System (INIS)

    Objective: To evaluate the efficacy and safety of low energy intracardiac cardioversion in persistent atria fibrillation. Methods: Low energy intracardiac cardioversion was performed by delivering R wave-synchronized biphasic shocks in 7 patients (4 men, 3 women) with persistent atrial fibrillation. Prior to the procedure, all patients underwent transesophageal echocardiographic examinations to rule out the presence of intracardiac thrombus and received subcutaneous injection of low molecular weight heparin for 3-5 days. Two custom-made 6 Fr catheters (Rhythm Technologies of Getz, USA) were used for de-fibrillation shock delivery. One catheter was positioned in the lower right atrium so that the majority of the catheter electrodes had firm contact with the right atrial free wall. The second catheter was placed randomly either in coronary sinus through right internal jugular vein or in the left pulmonary artery through femoral vein. In addition, a standard diagnostic 6-F quadrupolar catheter was placed at the right ventricular apex for ventricular synchronization and postshock ventricular pacing. Shocks were delivered by Implant Support Device (Model 4510, Teleceronics). After conversion, all patients were treated with intravenous amiodarone in the first 24 hours followed by oral administration. Results: In all 7 patients cardioversion of atrial fibrillation to sinus rhythm was successfully obtained. A mean of 2 ± 1 shocks per patient has been delivered with a total amount of 13 shocks. The average delivered energy was 7.8 ± 2.2 Joules. No complication occurred. At a mean follow-up of 18 ± 9 months, 4 of the 7 patients treated successfully showed sinus rhythm there after. Atrial fibrillation recurred in 3 patients at the second, fifth day and eighth month after cardioversion. Conclusions: Low energy intracardiac cardioversion is effective and safe, and can be easily performed in patients without general anesthesia. It offers a new option for restoring sinus

  12. Effect of edaravone plus beating-heart-preservation technique on myocardial protection in donation after cardiac death heart transplantation%依达拉奉联合供心复跳后不停跳保存技术提高缺氧诱导的无心跳猪供心移植效果

    Institute of Scientific and Technical Information of China (English)

    黄达德; 陈伟民; 谢建将; 李峰; 陈文广

    2011-01-01

    Objective To investigate the effect of edaravone plus beating-heart-preservation as well as beating-heart-transplantation technique on myocardial protection in donation after cardiac death (DCD) heart transplantation.Methods Twenty-four swine (body weight 28 ± 3 kg) were divided into two groups (n =12 each),and another twelve swine were used for blood donor.( 1 ) Experimental group:cardiac arrest was induced by asphyxiation (turning off the ventilation),and then the swine were subjected to 25-min warm ischemia,and cold oxygenated blood was perfused before the harvest of donor heart.Cardiac resuscitation was initiated by the ex vivo perfusion equipment and warm oxygenated blood was reperfused.Edaravone was given before harvesting of donor heart and in the early period of reperfusion.Donor hearts were kept beating throughout preservation and transplantation period.(2) Control group:all animals were treated in the same way except for without the application of edaravone.Hemodynamic,myocardial enzymes,and water content of myocardium were observed,and uhrastructural damage of cardiomyocytes was examined.Results All recipient animals could wean from cardiopulmonary bypass successfully.Left ventricular compliance and left ventricular contractility were significantly better preserved in experiment group than in control group.Though there was no significant difference in myocardial creatase level,the myocardial edema in experimental group was milder than in control group,and myocardial ultrastructure was better preserved in experimental group.Conclusion Heart from DCD,even though experienced 25-min warm ischemia after cardiac arrest by asphyxiation,still could be resuscitated via isolated heart perfusion equipment ( i.e.,beating-heart-preservation ) successfully.Furthermore,beating-hearttransplantation is feasible technically.Edaravone,a free-radical scavenger,could alleviate asphyxiation-induced myocardial injury,and further improve post-transplantation heart function

  13. In vivo CH3(CH2)11SAu SAM electrodes in the beating heart: in situ analytical studies relevant to pacemakers and interstitial biosensors.

    Science.gov (United States)

    Chou, Howard A; Zavitz, Daniel H; Ovadia, Marc

    2003-01-01

    To study in vivo modification of the SAM equivalent circuit when a highly ordered SAM is used as a bioelectrode, dodecanethiolate SAM-Au intramuscular electrodes were studied in living rat heart in a challenging in situ perfused rat model by impedance spectroscopy, cyclic voltammetry, and neutron activation analysis (NAA). The SAM layer experienced disintegration in vivo biological system, as NAA detected the presence of Au atoms that had leached into the surrounding living tissue. Therefore, the underlying Au surface became exposed during biological implant. Study by impedance spectroscopy, however, revealed perfect capacitive behavior for the SAM, similar to in vitro behavior. Electrodes showed a pure capacitive Nyquist plot with 86.1-89.4 degrees near-vertical line segments as the equivalent circuit locus, as for a parallel plate capacitor. Impedance magnitude varied linearly with 1/omega excluding diffusionally limited ionic charge transport. There was no diffusional conductive element Z(W infinity ) or spatially confined Warburg impedance Z(D). The effect of in vivo exposure of a highly ordered SAM is a 'sealing over' effect of new defects by the binding of proteinaceous or lipid species in the biological milieu, a fact of significance for SAM electrodes used either as pacemaker electrodes or as a platform for in vivo biosensors.

  14. Behçet’s Disease and Intracardiac Thrombosis: A Report of Three Cases

    Directory of Open Access Journals (Sweden)

    Nurşen Düzgün

    2013-01-01

    Full Text Available We present three patients with Behçet’s disease associated with intracardiac thrombus and pulmonary vascular involvement. One of these patients had also Budd-Chiari syndrome. All patients were treated with corticosteroid plus monthly intravenous cyclophosphamide as first line treatment and with no recurrences. Immunosuppressive therapy was successful in the treatment of intracardiac thrombus and also in the regression of pulmonary vascular thromboses in these patients. Intracardiac thrombus in Behçet’s disease is rarely seen. Behçet’s disease should be remembered in the differential diagnosis of the patients with intracardiac mass, especially in patients from the Mediterranean and Middle East populations.

  15. Wearable Beat to Beat Blood Pressure Monitor Project

    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...

  16. 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.

  17. 钠/氢交换抑制剂增强心肌保护液对无心跳猪供心的保护作用%Sodium-hydrogen exchange inhibitor HOE-642 improves the protective effects of cardioplegia on porcine hearts from non-heart-beating donors

    Institute of Scientific and Technical Information of China (English)

    李恒昌; 许立新; 佘守章; 许学兵; 胡善鉴; 刘焕仪

    2011-01-01

    OBJECTIVE To evaluate the possibility of heart transplantation with non - heart - beating donor ( NHBD ) graft,and the protective effects of combining cardioplegia with Na+/H+ exchange inhibitor HOE - 642 on NHBD heart. METHODS Twenty - four male adult porcines were randomly assigned to experimental group ( group E,n = 6 ) and control group ( group C , n = 6 ).Donor hearts in the group E were harvested from NHBD in which hearts arrest were induced by means of exsanguination, immersed in cold cardioplegia solution for 4 hours and followed hy orthotropic heart transplantation. In addition, those donor hearts received an intravenous injection with HOE - 642 ( 2 mg/kg ) 5 minutes before normothermia ischemia and were preserved with Stanford solution containing HOE - 642. Those donor hearts were perfused with cardioplegia containing HOE - 642 before transplantation and every 30 minutes during transplantation. At last.the aortic clamp was released and recipient animals received a single intravenous dose of HOE642 ( 2 mg/kg ) 5 minutes after finishing the procedure. Donor hearts in the group C were harvested from heart - beating donor ( HBD ) and treated as in the group E but a substitute of HOE - 642 was normal saline. All harvested hearts were followed by orthotropic heart transplantation. Left ventricular mechanical performance ( LVPDP, LVEDP, ± dp/dt ) were examined 1 hour and 2 hours after the aortic clamp released, myocardial water content were determined, myocardial enzymes were evaluated and myocardium tissues were also analyzed under light microscopy and electron microscopy. RESULTS All animals were weaned from cardiopulmonary bypass successfully. There were no significant differences between the group E and group C in left ventricular mechanical performance ( P > 0. 05 ),mvocardial water content ( P >0. 05 ) and myocardial enzymes ( P >0. 05 ). There was no serious cell damage when examined under light microscopy and electron microscopy and cardiomyocytes

  18. Effects of the Selective Stretch-Activated Channel Blocker GsMtx4 on Stretch-Induced Changes in Refractoriness in Isolated Rat Hearts and on Ventricular Premature Beats and Arrhythmias after Coronary Occlusion in Swine.

    Directory of Open Access Journals (Sweden)

    José A Barrabés

    Full Text Available Mechanical factors may contribute to ischemic ventricular arrhythmias. GsMtx4 peptide, a selective stretch-activated channel blocker, inhibits stretch-induced atrial arrhythmias. We aimed to assess whether GsMtx4 protects against ventricular ectopy and arrhythmias following coronary occlusion in swine. First, the effects of 170-nM GsMtx4 on the changes in the effective refractory period (ERP induced by left ventricular (LV dilatation were assessed in 8 isolated rat hearts. Then, 44 anesthetized, open-chest pigs subjected to 50-min left anterior descending artery occlusion and 2-h reperfusion were blindly allocated to GsMtx4 (57 μg/kg iv. bolus and 3.8 μg/kg/min infusion, calculated to attain the above concentration in plasma or saline, starting 5-min before occlusion and continuing until after reflow. In rat hearts, LV distension induced progressive reductions in ERP (35±2, 32±2, and 29±2 ms at 0, 20, and 40 mmHg of LV end-diastolic pressure, respectively, P<0.001 that were prevented by GsMTx4 (33±2, 33±2, and 32±2 ms, respectively, P=0.002 for the interaction with LV end-diastolic pressure. Pigs receiving GsMtx4 had similar number of ventricular premature beats during the ischemic period as control pigs (110±28 vs. 103±21, respectively, P=0.842. There were not significant differences among treated and untreated animals in the incidence of ventricular fibrillation (13.6 vs. 22.7%, respectively, P=0.696 or tachycardia (36.4 vs. 50.0%, P=0.361 or in the number of ventricular tachycardia episodes during the occlusion period (1.8±0.7 vs. 5.5±2.6, P=0.323. Thus, GsMtx4 administered under these conditions does not suppress ventricular ectopy following coronary occlusion in swine. Whether it might protect against malignant arrhythmias should be tested in studies powered for these outcomes.

  19. Off beat: pluralizing rhythm

    NARCIS (Netherlands)

    J.H. Hoogstad; B. Stougaard Pedersen

    2013-01-01

    Off Beat: Pluralizing Rhythm draws attention to rhythm as a tool for analyzing various cultural objects. In fields as diverse as music, culture, nature, and economy, rhythm can be seen as a phenomenon that both connects and divides. It suggests a certain measure with which people, practices, and cul

  20. HOE-642联合尼可地尔对无心跳猪供心的保护作用%Cardial protective effects of Na+/H+ exchange inhibitor (HOE-642) plus K-ATP opener (Nicorandil) on heart harvested from exsanguiated porcine non-heart-beating donor (NHBD)

    Institute of Scientific and Technical Information of China (English)

    黄达德; 曾秀仪; 陈伟民; 王德才; 陈文广; 谢小筠; 许立新; 李恒昌; 胡善鉴; 冯至欣

    2008-01-01

    Objective To evaluate the possibility of heart transplantation with non-heart-beating donor (NHBD) graft, and the cardial protective effects of Na+/H+ exchange inhibitor (HOE-642) plus KATP channel opener (Nicorandil) on NHBD. Methods Twenty-four male adult porcine were randomly assigned to two groups: (1) Donor hearts harvested from NHBD in which heart arrest was induced by means of exsanguination (keeping blood pressure at zero for 30 rain, and heart arrest for 9 to 12 min), and donor heart was protected by means of HOE-642/Nicorandil enriched Stanford solution as well as HOE-642/Nicorandil-enriched blood cardioplegia, in addition, HOE-642 was intravenously used before exsanguination and during the initial period of reperfusion (i. e. , after decrossclamping of aorta) (experimental group, n = 6) ; (2) Donor hearts harvested from heart-beating donor (HBD), and protected by clinically used routing method (control group, n = 6). All harvested hearts in both groups underwent a 4 h cold storage, followed by orthotropic heart transplantation. Left ventricular mechanical performance (LVPDP, LVEDP, + dp/dt, -dp/dt), and myocardial water content (MWC) were determined, hearts were also analyzed under the light microscopy or electron microscopy for structural injuries. Results All animals could wean from cardiopulmonary bypass successfully.There were no significant differences between experimental group and control group in left ventricular mechanical performance and MWC (P>0. 05). There was no serious cell damage when examined under the light and transmission electron microscopy and cardiomyocytes were well preserved in both groups. Conclusion Heart transplantation using NHBD heart could lead to the same encouraging outcome as using HBD heart, and this kind of donor hearts might be an ahernative potential resource of graft for heart transplantation. HOE-642 plus nicorandil is feasible to provide optimal protection for NHBD heart.%目的 探讨无心跳供者(NHBD)的心

  1. [Quantitative Evaluation of Intracardiac Blood Flow by Left Ventricle Dynamic Anatovy Based On Exact Solutions of Non-Stationary Navier-Stocks Equations for Selforganized tornado-Like Flows of Viscous Incompresssible Fluid].

    Science.gov (United States)

    Talygin, E A; Zazybo, N A; Zhorzholiany, S T; Krestinich, I M; Mironov, A A; Kiknadze, G I; Bokerya, L A; Gorodkov, A Y; Makarenko, V N; Alexandrova, S A

    2016-01-01

    New approach to intracardiac blood flow condition analysis based on geometric parameters of left ventricle flow channel has been suggested. Parameters, that used in this method, follow from exact solutions of nonstationary Navier-Stocks equations for selforganized tornado-like flows of viscous incompressible fluid. The main advantage of this method is considering dynamic anatomy of intracardiac cavity and trabeculae relief of left ventricle streamlined surface, both registered in a common mri-process, as flow condition indicator. Calculated quantity options that characterizes blood flow condition can be use as diagnostic criterias for estimation of violation in blood circulation function which entails heart ejection reduction. Developed approach allows to clarify heart jet organization mechanism and estimate the share of the tornado-like flow self-organization in heart ejection structure.

  2. Intramyocardial transplantation of undifferentiated rat induced pluripotent stem cells causes tumorigenesis in the heart.

    Directory of Open Access Journals (Sweden)

    Yuzhen Zhang

    Full Text Available BACKGROUND: Induced pluripotent stem cells (iPSCs are a novel candidate for use in cardiac stem cell therapy. However, their intrinsic tumorigenicity requires further investigation prior to use in a clinical setting. In this study we investigated whether undifferentiated iPSCs are tumorigenic after intramyocardial transplantation into immunocompetent allogeneic recipients. METHODOLOGY/PRINCIPAL FINDINGS: We transplanted 2 × 10(4, 2 × 10(5, or 2 × 10(6 cells from the established rat iPSC line M13 intramyocardially into intact or infarcted hearts of immunocompetent allogeneic rats. Transplant duration was 2, 4, or 6 weeks. Histological examination with hematoxylin-eosin staining confirmed that undifferentiated rat iPSCs could generate heterogeneous tumors in both intracardiac and extracardiac sites. Furthermore, tumor incidence was independent of cell dose, transplant duration, and the presence or absence of myocardial infarction. CONCLUSIONS/SIGNIFICANCE: Our study demonstrates that allogeneic iPSC transplantation in the heart will likely result in in situ tumorigenesis, and that cells leaked from the beating heart are a potential source of tumor spread, underscoring the importance of evaluating the safety of future iPSC therapy for cardiac disease.

  3. IRAN THE BEATING HEART OF ASIA

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Iran is a vast country covering 1,648,000 square kilometers in southwestern Asia. Its neighbors are Turkmenistan, Azerbaijan and Armenia on the north, Afghanistan and Pakistan on the east, and Turkey and Iraq on the west.

  4. Open Kazakhstan, the Beating Heart of Eurasia

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Kazakhstan lies in the north of the central Asian republics and is bounded by Russia in the north, China in the east, Kyrgyzstan and Uzbekistan in the south, and the Caspian Sea and part of Turkmenistan in the west. It has almost 1,177 mi (about 1,894 km) of coastline on the Caspian Sea.

  5. Measuring Cosmic Distances with Stellar Heart Beats

    Science.gov (United States)

    2004-10-01

    VLTI Watches the Changing Size of Bright Southern Cepheids Summary Taking advantage of the very high spatial resolution provided by the Very Large Telescope Interferometer, a team of French and Swiss astronomers [1] has measured directly the change in angular diameter of four southern Cepheid variable stars over their pulsation cycle. When combined with spectroscopic radial velocity measurements, this allowed the astronomers to measure very accurately the distances of these stars in a quasi-geometrical way, and to calibrate the zero-point of the Cepheid Period-Luminosity empirical law. These observations constitute a fundamental step towards an independent verification of the extragalactic distance scale by interferometry. PR Photo 30a/04: Observation Techniques of the Baade-Wesselink Method. PR Photo 30b/04: Paranal Platform and VLTI Baselines Used. PR Photo 30c/04: Pulsation of the Cepheid Variable L Car. (VINCI/VLTI) PR Photo 30d/04: Period-Luminosity relation for Cepheids. (VINCI/VLTI) Cepheids and the cosmic distance ladder It is very difficult to measure the distance to an astronomical object. In fact, this is one of the greatest challenges facing astronomers. There is indeed no accurate, direct way to determine the distance to galaxies beyond the Milky Way: astronomers first determine the distance to nearby stars in our galaxy as accurately as possible and then use a series of other techniques that reach progressively further into space to estimate distances to more distant systems. This process is often referred as the "cosmic distance ladder". Over the years, a number of different distance estimators have been found. One of these is a particular class of stars known as Cepheid variables. They are used as one of the first "steps" on this cosmic distance ladder. Cepheids are rare and very luminous stars whose luminosity varies in a very regular way. They are named after the star Delta Cephei in the constellation of Cepheus, the first known variable star of this particular type and bright enough to be easily seen with the unaided eye. In 1912, American astronomer Henrietta Leavitt observed 20 variable stars of the Cepheid-type in the Small Magellanic Cloud (SMC), one of the closest galaxies to the Milky Way. For all purposes, these stars are all at the same distance (the size of the SMC is negligible compared to its much larger distance from us). Apparently brighter stars in this group are thus also intrinsically brighter (more luminous). Henrietta Leavitt discovered a basic relation between the intrinsic brightness and the pulsation period of Cepheid variable stars in the SMC and showed that intrinsically brighter Cepheids have longer periods. This relation is now known as the "Period-Luminosity relation" and is an important way to derive the distance to stars of this type. By measuring the period of a Cepheid star, its intrinsic brightness can be deduced and from the observed apparent brightness, the distance may then be calculated. In this way, Cepheid stars are used by astronomers as one of the "standard candles" in the Universe. They act either as distance indicators themselves or are used to calibrate other distance indicators. The Cepheid stars have taken on an even more important role since the Hubble Space Telescope Key Project on the extragalactic distance scale relies completely on them for the calibration of distance indicators to reach cosmologically large distances. In other words, if the calibration of the Cepheid Period-Luminosity relation were wrong, the entire extragalactic distance scale and with it, the rate of cosmic expansion and the related acceleration, as well as the estimated age of the Universe, would also be off. A main problem is thus to calibrate as accurately as possible the Period-Luminosity relation for nearby Cepheids. This requires measuring their distances with the utmost precision, a truly daunting task. And this is where interferometry now enters the picture. The Baade-Wesselink method ESO PR Photo 30a/04 ESO PR Photo 30a/04 Title [Preview - JPEG: 400 x 345 pix - 104k] [Normal

  6. beat a dead horse

    Institute of Scientific and Technical Information of China (English)

    吕浙

    2005-01-01

    beat a dead horse的字面意思为“鞭打死马”。“鞭打死马”有什么作用?毫无疑问,一点意义也没有。因此,该习语的意思相当于中文的“徒劳,白费力气,白费口舌”。如:

  7. Role of Intracardiac echocardiography in Atrial Fibrillation Ablation

    Directory of Open Access Journals (Sweden)

    Antonio Dello Russo, MD PhD

    2013-04-01

    Full Text Available In the recent years, several new evidences support catheter-based ablation as a treatment modality of atrial fibrillation (AF. Based on a plenty of different applications, intracardiac echocardiography (ICE is now a well-established technology in complex electrophysiological procedures, in particular in AF ablation. ICE contributes to improve the efficacy and safety of such procedures defining the anatomical structures involved in ablation procedures and monitoring in real time possible complications. In particular ICE allows: a correct identification of the endocardial structures; a guidance of transseptal puncture; an assessment of accurate placement of the circular mapping catheter; an indirect evaluation of evolving lesions during radiofrequency (RF energy delivery via visualization of micro and macrobubbles tissue heating; assessment of catheter contact with cardiac tissues. Recently, also the feasibility of the integration of electroanatomical mapping (EAM and intracardiac echocardiography has been demonstrated, combining accurate real time anatomical information with electroanatomical data. As a matter of fact, different techniques and ablation strategies have been developed throughout the years. In the setting of balloon-based ablation systems, recently adopted by an increasing number of centers, ICE might have a role in the choice of appropriate balloon size and to confirm accurate occlusion of pulmonary veins. Furthermore, in the era of minimally fluoroscopic ablation, ICE has successfully provided a contribute in reducing fluoroscopy time. The purpose of this review is to summarize the current applications of ICE in catheter based ablation strategies of atrial fibrillation, focusing-on electronically phased-array ICE.

  8. Simultaneous beat-by-beat investigation of the effects of the Valsalva maneuver on left and right ventricular filling and the possible mechanism.

    Directory of Open Access Journals (Sweden)

    Zhen Wang

    Full Text Available Although the influence of the Valsalva maneuver on the heart and circulatory system has been investigated, the mechanism of intrathoracic pressure influencing cardiovascular function is unclear. To test our hypothesis that the interaction between the anatomy-determined partially-intrathoracic system and the fully-intrathoracic system might explain those issues and help to disclose the mechanism, we used the Hitachi dual pulse wave Doppler echocardiographic apparatus to investigate simultaneously the beat-by-beat influence of 40-mmHg Valsalva maneuver on left and right cardiac ventricular filling in 30 male adult volunteers. The mitral and tricuspid blood inflow velocity spectra during the Valsalva maneuver were recorded simultaneously. The peak velocity (PV, velocity-time integral (VTI and inflow volume (IV of each cycle were measured or calculated. The PV, VTI and IV of the left heart remained unchanged at the first beat after the Valsalva maneuver onset (compared with those at rest, p>0.1 and then decreased gradually to the lowest at the 11±1.2th beat (range, 9th to 12th beat. Simultaneously, the PV, VTI and IV of the right heart decreased significantly (p<0.05 at the first cycle, decreased rapidly to the lowest at the 6±0.8th beat (range, 4th to 7th beat and then increased gradually to the 9±1.3th beat (range, 8th to 10th beat. These results suggest that the left heart and right heart have different physiological responses to the Valsalva maneuver. These could be explained by our hypothesis, the interaction between the partially-intrathoracic system and the fully-intrathoracic system, which might help to disclose the mechanism of how intrathoracic pressure influences the heart and circulatory system.

  9. Effect of warm ischemia time to the islet function on the non-heart-beating donor rat%热缺血时间对无心跳大鼠胰岛获取和功能的影响

    Institute of Scientific and Technical Information of China (English)

    宋文卿; 刘永锋; 程颖; 车彦鹏; 梁世博

    2015-01-01

    Objective To observe the influence of warm ischemia time on acquisition of rat pancreatic islets and islet function.Method Male Wistar rats were used.After heart beats stopped,the pancreases in four groups of rats were harvested,and warm ischemia time was 0,15,30 and 45 min separately.The pancrease was preserved in UW at 4℃C for 8 h,and subjected to injection of collagenase solutions.After islets were acquired,the purity,survival rate and islet activity were tested,and statistical analysis was performed.Result The number of islets obtained in 0 min group,15 min group,30 min group and 45 min group was (433 ± 41),(396 ± 38),(350 ± 31) and (66 ± 17)IEQ/one,islet viability was 94%,88%,77% and 25%,and purity was 88%,78%,60% and 32%,and insulin release index was 2.38 ± 0.23,2.25 ± 0.18,2.19-± 0.18 and 1.25 ± 0.12,respectively.There was no significant difference in islet number,purity,survival rate and activity 15 min group and 30 min group between 15 min group or 30 min group and 0 min group (P>0.05).There was significant difference between 45 min group and 0 min group in islet number,purity,survival rate and activity (P<0.05).The survival rate and purity in 45 min group were lower than the clinical standards for islet transplantation (survival rate > 75%,and purity > 50%).Conclusion Warm ischemia time of 15 min in non-heart-beating brain death(NHBD) rats had no effect on islet isolation and purification.Warm ischemia time within 30 min showed no significant influence on islets of NHBD rats,which can be used in islet transplantation.Warm ischemia time at 45 min showed significant influence on islets of NHBD rats,which can't be used in islet transplantation.%目的 观察不同热缺血时间对获取的大鼠胰岛及胰岛功能的影响.方法 采用雄性Wistar大鼠.在大鼠心跳停搏后,获取热缺血时间分别为0 min、15 min、30 min、45 min的4组大鼠胰腺,给予4℃的UW液保存8h,再将胶原酶溶液10 ml注

  10. An efficient method for ectopic beats cancellation based on radial basis function.

    Science.gov (United States)

    Mateo, Jorge; Torres, Ana; Rieta, José J

    2011-01-01

    The analysis of the surface Electrocardiogram (ECG) is the most extended noninvasive technique in cardiological diagnosis. In order to properly use the ECG, we need to cancel out ectopic beats. These beats may occur in both normal subjects and patients with heart disease, and their presence represents an important source of error which must be handled before any other analysis. This paper presents a method for electrocardiogram ectopic beat cancellation based on Radial Basis Function Neural Network (RBFNN). A train-able neural network ensemble approach to develop customized electrocardiogram beat classifier in an effort to further improve the performance of ECG processing and to offer individualized health care is presented. Six types of beats including: Normal Beats (NB); Premature Ventricular Contractions (PVC); Left Bundle Branch Blocks (LBBB); Right Bundle Branch Blocks (RBBB); Paced Beats (PB) and Ectopic Beats (EB) are obtained from the MIT-BIH arrhythmia database. Four morphological features are extracted from each beat after the preprocessing of the selected records. Average Results for the RBFNN based method provided an ectopic beat reduction (EBR) of (mean ± std) EBR = 7, 23 ± 2.18 in contrast to traditional compared methods that, for the best case, yielded EBR = 4.05 ± 2.13. The results prove that RBFNN based methods are able to obtain a very accurate reduction of ectopic beats together with low distortion of the QRST complex.

  11. Beat wave development work

    International Nuclear Information System (INIS)

    The first phase of experiments on beat wave acceleration have been completed at UCLA. Here we examined the suitability of a theta pinch as a plasma source. The beatwave was excited to amplitudes providing GeV/m-scale accelerating fields. However, trapped magnetic fields within the theta-pinch plasma hindered the injection of test particles. Optical diagnostics were developed to measure the accelerating gradient-length product which was found to be around 3 MeV. Future plans are also discussed. copyright 1989 American Institute of Physics

  12. In vivo re-distribution of intra-coronary transplanted stem cells into beating and arrested hearts by magnetic resonance imaging in an acute myocardial infarction swine model%磁共振成像对猪不同心脏状态下经冠状动脉干细胞移植后体内再分布的评价

    Institute of Scientific and Technical Information of China (English)

    陆敏杰; 马宁; 尹刚; 王琳琳; 唐跃; 赵世华; 宋鹏; 蒋世良; 刘琼; 闫朝武; 张岩; 凌坚; 程怀兵

    2010-01-01

    目的 探讨磁共振成像在停跳与不停跳两种心脏状态下,对猪心肌梗死模型经冠状动脉注射骨髓间充质干细胞后全身各主要脏器干细胞早期再分布中的应用价值.方法 用带球囊导管经股动脉选择性插管至雌猪左冠状动脉前降支,在第二对角支的近端将球囊扩张90 min建立急性心肌梗死模型.模型建立后7 d,随机分为4组,分别为不停跳心脏细胞移植组(不停跳组,n=6)与对照组(n=6),停跳心脏细胞移植组(停跳组,n=6)与对照组(n=6).超顺磁氧化铁颗粒(SPIO)标记的干细胞移植3 d后,行磁共振T2*WI示踪检查.取动物心、肝、脾、肺、肾脏的标本,用实时定量聚合酶链反应检测雄性细胞特异性的SRY基因,切片进行普鲁士蓝染色,观察细胞在体内的分布和形态.结果 除肾脏外,心、脾、肝中干细胞移植组T2*值较对照组差异均有统计学意义,但移植组在不同心脏状态下不停跳组与停跳组心肌T2*值差异无统计学意义[(-7.81±2.03)ms比(-6.56±1.72)ms,P>0.05],而不停跳组脾脏及肝脏的T2*值明显低于停跳组[脾脏:(-16.72±2.83)ms比(-22.18±3.98)ms,P<0.01,肝脏:(-2.40±0.44)ms比(-5.32±3.40)ms,P<0.05],在肾脏中两组差异无统计学意义.SRY基因在不停跳组及停跳组的脾脏及肝脏的表达差异有统计学意义,病理学检查见移植细胞呈普鲁士蓝染色阳性.结论 干细胞SPIO标记后,磁共振成像可以作为方便而有效的手段在移植早期活体示踪干细胞,评价其在体内的分布情况.经冠状动脉途径注射骨髓间充质干细胞后,许多细胞流向心脏以外的器官,尤其是脾脏.心脏停跳与不停跳状态下经冠状动脉注射骨髓间充质干细胞对干细胞在心脏的滞留无明显差别.%Objective To analyze the stem cell re-distribution after intra-coronary infusion (ICI)into arrested and beating hearts in a swine myocardial infarction ( MI ) model using magnetic

  13. Early embryonic intra-cardiac flow fields at three idealized ventricular morphologies

    Science.gov (United States)

    Pekkan, Kerem; Jamaly, Mohammad; Kara, Burak; Keller, Bradley; Sotiropoulos, Fotis

    2009-11-01

    Pulsatile 3D multiple inlet/outlet flow within tiny (100-300μm dia) embryonic ventricles feature distinct intra-cardiac flow streams whose role in regulating the morphogenesis of spiral aorto-pulmonary septum has long been debated. The low Re number flow regimes limit mixing of these streams as replicated in our flow-visualization experiments with chick embryos. A state-of-the art high-resolution immersed boundary CFD solver which was developed for complex patient-specific cardiovascular internal flow problems is applied and optimized for this problem. Idealized tubular ventricles at 3 major embryonic stages (straight, C- and D- loops) are created by our sketch-based anatomical editing tool. CFD results are validated with PIV measurements acquired from a micro-fabricated C-loop stage replica and in vivo flow vis data from confocal microscopy. This model provided the inlet velocity profile for arterial models and flow fields at the inner curvature of embryonic hearts for different ventricular topologies are compared for off-design modes.

  14. A Novel Ex Ovo Banding Technique to Alter Intracardiac Hemodynamics in an Embryonic Chicken System.

    Science.gov (United States)

    Menon, Vinal; Junor, Lorain; Balhaj, Marwa; Eberth, John F; Potts, Jay D

    2016-01-01

    The new model presented here can be used to understand the influence of hemodynamics on specific cardiac developmental processes, at the cellular and molecular level. To alter intracardiac hemodynamics, fertilized chicken eggs are incubated in a humidified chamber to obtain embryos of the desired stage (HH17). Once this developmental stage is achieved, the embryo is maintained ex ovo and hemodynamics in the embryonic heart are altered by partially constricting the outflow tract (OFT) with a surgical suture at the junction of the OFT and ventricle (OVJ). Control embryos are also cultured ex ovo but are not subjected to the surgical intervention. Banded and control embryos are then incubated in a humidified incubator for the desired period of time, after which 2D ultrasound is employed to analyze the change in blood flow velocity at the OVJ as a result of OFT banding. Once embryos are maintained ex ovo, it is important to ensure adequate hydration in the incubation chamber so as to prevent drying and eventually embryo death. Using this new banded model, it is now possible to perform analyses of changes in the expression of key players involved in valve development and to understand the role of hemodynamics on cellular responses in vivo, which could not be achieved previously. PMID:27213265

  15. 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.

  16. Resonant Bloch-wave beatings.

    Science.gov (United States)

    Kartashov, Yaroslav V; Vysloukh, Victor A; Torner, Lluis

    2014-07-01

    We introduce Bloch-wave beatings in arrays of multimode periodically bent waveguides with a transverse refractive index gradient. The new phenomenon manifests itself in the periodic drastic increase of the amplitude of the Bloch oscillations that accompanies resonant conversion of modes guided by the individual waveguides. The Bloch-wave beatings are found to be most pronounced when the length of the resonant mode conversion substantially exceeds the longitudinal period of the Bloch oscillations. The beating frequency decreases when the amplitude of waveguide bending decreases, while the beating amplitude is restricted by the amplitude of the Bloch oscillations that emerge from the second allowed band of the Floquet-Bloch lattice spectrum.

  17. Resonant Bloch-wave beatings

    CERN Document Server

    Kartashov, Yaroslav V; Torner, Lluis

    2014-01-01

    We introduce Bloch-wave beatings in arrays of multimode periodically bent waveguides with a transverse refractive index gradient. The new phenomenon manifests itself in the periodic drastic increase of the amplitude of the Bloch oscillations that accompanies resonant conversion of modes guided by the individual waveguides. The Bloch-wave beatings are found to be most pronounced when the length of the resonant mode conversion substantially exceeds the longitudinal period of the Bloch oscillations. The beating frequency decreases when the amplitude of waveguide bending decreases, while the beating amplitude is restricted by the amplitude of the Bloch oscillations that emerge from the second allowed band of the Floquet-Bloch lattice spectrum.

  18. Symbolic Dynamics Analysis of Short Data Sets: an Application to Heart Rate Variability from Implantable Defibrillator Devices

    Science.gov (United States)

    Zebrowski, Jan J.; Baranowski, Rafal; Przybylski, Andrzej

    2003-07-01

    A method is described for the assessment of the complexity of short data sets by nonlinear dynamics. The method was devised for and tested on human heart rate recordings approximately 2000 to 9000 RR intervals long which were extracted from the memory of implantable defibrillator devices (ICD). It is, however, applicable in a more general context. The ICDs are meant to control life-threatening episodes of ventricular tachycardia and/or ventricular fibrillation by applying a electric shock to the heart through intracardiac electrodes. It is well known that conventional ICD algorithms yield approximately 20--30 % of spurious interventions. The main aim of this work is to look for nonlinear dynamics methods to enhance the appropriateness of the ICD intervention. We first showed that nonlinear dynamics methods first applied to 24-hour heart rate variability analysis were able to detect the need for the ICD intervention. To be applicable to future ICD use, the methods must also be low in computational requirements. Methods to analyse the complexity of the short and non-stationary sets were devised. We calculated the Shannon entropy of symbolic words obtained in a sliding 50 beat window and analysed the dependence of this complexity measure on the time. Precursors were found extending much earlier time than the time the standard ICD algorithms span.

  19. Clinical study of acupuncture combined with medicine in the treatment of coronary heart disease complicated with ven-tricular premature beat%针药结合治疗冠心病复杂性室性早搏的临床研究

    Institute of Scientific and Technical Information of China (English)

    陈莘桃; 谭小华; 周全; 马俐; 朱文红; 陆青研; 谢月萍; 吴曙粤

    2015-01-01

    Objective To investigate the effect of acupuncture and medicine combined treatment on coronary heart disease (CHD)complicated with complex ventricular premature beat,and thus provide a new way of significant effect,safe,convenient operation and no adverse reactions for the clinical treatment of coronary heart disease complicated with ventricular premature beat. Methods Ninety-nine coronary heart disease patients complicated with complex ventricular premature beat were divided into Wenxin granule plus acupuncture treatment group,Wenxin granule group and acupuncture group. Patients were all deactivated other antiarrhythmic drugs,but still accepted treatment for primary disease drugs. The three groups were treated for 1 month,the clinical symptoms,electrocardiogram and dynamic electrocardiogram,liver and kidney function were observed. Results The treatment effect of Wenxin granule plus acupuncture treatment group was significantly better than that of Wenxin granule group and acupuncture group,the total effective rate was 90. 9% ;the effect of Wenxin granule group was better than that of acupuncture group,and the effective rate was 63. 6% . Before and after treatment,the effect had significant difference in the Wenxin granule plus acupuncture treatment group and Wenxin granule group(P 0. 05). After treatment,the 24 h dynamic electrocardiogram of ventricular premature beat reduce number of Wenxin granule plus acupuncture treatment group was better than that of Wenxin granule group(P 0.05)。治疗后,24 h 动态心电图室性早搏减少数针药组大于稳心组( P <0.05)及针刺组(P <0.01),且稳心组治疗后24 h 动态心电图室性早搏减少数大于针刺组(P <0.01)。结论针药结合治疗冠心病复杂性室性早搏的效果优于单用药物治疗或针刺治疗,单用药物治疗的结果优于单用针刺治疗。

  20. 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.

  1. The role of stents in the treatment of congenital heart disease: Current status and future perspectives

    OpenAIRE

    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 characteri...

  2. The Diagnosis and Surgical Management of Intracardiac Quill Foreign Body in a Dog.

    Science.gov (United States)

    Nucci, Daniel Joseph Santiago; Liptak, Julius

    2016-01-01

    A dog was referred to Alta Vista Animal Hospital with a porcupine quill penetrating the right ventricle. The presenting complaint was tachypnea and dyspnea secondary to bilateral pneumothorax. Computed tomography revealed bilateral pneumothorax without evidence of quills. A median sternotomy was performed and the quill was removed. The dog recovered uneventfully. Quill injuries are common in dogs; however, intracardiac quill migration is rare. Dogs without evidence of severe cardiac injury secondary to intracardiac foreign bodies may have a good prognosis. PMID:26606212

  3. Masses for Galactic Beat Cepheids

    Science.gov (United States)

    D'Cruz, Noella L.; Morgan, Siobahn M.; Böhm-Vitense, Erika

    2000-08-01

    Accurate mass determinations for Cepheids may be used to determine the degree of excess mixing in the interiors of their main-sequence progenitors: the larger the excess mixing, the larger the luminosity of the Cepheid of a given mass, or the smaller the mass of a Cepheid with given luminosity. Dynamical masses determined recently for a few Cepheid binaries indicate excess mixing somewhat stronger than that corresponding to the convective overshoot models by Schaller et al. Beat Cepheids can be used similarly to test main-sequence mixing in stellar interiors. The period ratios for beat Cepheids depend on luminosity, Teff, heavy element abundance, and mass. By comparing pulsational models and the observationally derived luminosity, Teff, metallicities, and period ratios it is possible to obtain masses for these stars, the so-called beat masses. With the old opacities masses much smaller than the evolutionary masses were obtained. With the new OPAL opacities a beat mass close to the dynamical mass was obtained for the binary beat Cepheid Y Carinae, showing that it is now possible to obtain reliable beat masses. In this paper, we determine beat masses for seven Galactic beat Cepheids for which photometric and spectroscopic data are available. We find an average mass around 4.2+/-0.3 Msolar for these stars, though the actual error limits for each star may be larger mainly because of uncertainties in E(B-V) and the heavy element abundances. (As derived spectroscopically, beat Cepheids are in general metal-poor, with -0.4relation between the derived beat masses and the luminosities again indicates excess mixing that is somewhat larger than that corresponding to the models by Schaller et al.

  4. 参麦注射液在体外循环心脏不停跳手术中的心肌保护作用%Myocardial protection of Shenmai injection in patients subject to beating-heart surgery

    Institute of Scientific and Technical Information of China (English)

    阳诺; 冼磊; 陈铭伍; 郭建极; 胡松

    2013-01-01

    Objective To evaluate the myocardial protective effects of Shenmai injection in patients udnergoing cardiopul-monary bypass (CPB) surgery on beating-heart.Methods Sixty patients with rheumatic heart disease preparing for mitral valve replacement were randomly divided into two groups:control group (group A,n =30) and experimental group (group B,n =30).The patients in group B were given Shenmai injection 0.6 ml/kg in circuit priming fluids,and those in group A were given equal volume of normal saline.Blood samples were collected before surgery (T1),at 30 min of CPB (T2),at the end of CPB (T3) and operation (T4),24 h after operation (T5),and 72 h after operation (T6) for assessment of lactate dehydrogenase (LDH),CK-MB,cardiac Troponin T (cTnT),superoxide dismutase (SOD) and malondialdehyde (MDA).Results (1) The levels of LDH were significantly lower in group B than in group A at T3 to T6 [(258.55 ± 21.83) U/L vs.(345.12 ± 25.28) U/L,(306.40 ± 26.11) U/L vs.(396.36 ± 22.66) U/L,(335.62 ± 26.72) U/L vs.(415.74 ± 39.56) U/L,(380.00 ± 31.53) U/L vs.(435.45 ±41.39) U/L] (P <0.05).The levels of CK-MB were significantly lower in group B than in group A at T2 to T5 [(33.70 ± 12.60) U/L vs.(42.31 ± 11.03) U/L,(48.91 ± 12.30) U/L vs.(78.81 ±15.03) U/L,(55.82±15.28) U/Lvs.(90.76±20.14) U/L,(73.09 ±24.34) U/Lvs.(109.05 ±24.33) U/L] (P <0.05).The levels of cTnT were significantly lower in group B than in group AatT2 to T6 [(0.89 ± 0.27) U/Lvs.(2.61 ±0.25) U/L,(5.49±1.79) U/Lvs.(11.48±2.41) U/L,(8.31 ±2.44) U/L vs.(18.34 ±3.76) U/L,(17.91 ±3.42) U/L vs.(27.05 ±4.24) U/L,(5.10 ± 1.42) U/L vs.(11.19 ±2.80) U/L] (P<0.05).(2) The levels of SOD were significantly higher in group B than in group A at T2 to T6[(68.69 ±7.26) U/L vs.(55.22 ±7.30) U/L,(54.28 ±7.94) U/L vs.(35.11 ±6.61) U/L,(44.03 ±6.17) U/L vs.(25.41 ±3.98) U/L,(53.93 ±6.76) U/L vs.(41.60 ± 3.79) U/L,(64.27 ± 7.13) U/L vs.(50.02 ± 4.45) U/L] (P < 0.05).The levels of MDA were

  5. Protective effects of ulinastatin during non-heart-beating donors lung transplantation%乌司他丁对无心跳兔供肺的保护作用

    Institute of Scientific and Technical Information of China (English)

    倪斌; 马海涛; 谈震东; 祝冒善; 朱逸; 李畅; 宋心雨

    2009-01-01

    Objective To investigate the protective effects of treatment with ulinastatin (UTD during rabbit non-heart-beating donors lung transplantation, and explore the possible mechanism.Methods Thirty rabbits were divided randomly into three groups: group A as control group, group B as UTI flushing group, and group C as UTI preconditioning plus flushing group.In group A donors were exsanguinated to maintain hypotension for 30 rain before intravenous injection of potassium chloride to make heart arrest.After a period of 1 h warm ischemia in situ, topical cooling was executed.Meanwhile, the donor lungs were antegradely flushed through pulmonary arteries with low-potassium-dextron (LPD) solution at 4℃.After flushing in situ, lung-heart blocks were harvested and store at 4 ℃ for another 5 h, then perfused for 90 min in isolated, ventilated, blood-perfused rabbit lung models.Pulmonary venous blood samples were collected for blood gas analysis at 1st, 30th, 60th, and 90th min after initiation of reperfusion.At the same time, PAwP was recorded respectively.Lung samples were obtained at the end of reperfusion.The pulmonary water index (W/D), tissue myeloperoxidase (MPO) activity, tissue malondialdehyde (MDA) content, and mRNA expression of IL-8 and ICAM-1 were measured.Microscopic examination of donor lungs was conducted.In group B, the same procedures were conducted as in group A except for adding UTI (500 000 U/L) to LPD solution.In group C, except that a bolus of UTI (50 000 U/kg) was given to donors intravenously during hypotension, the same procedures were conducted as in group B.Results (1) In all three groups, there were same tendencies of gradually decreasing of PO2 levels; and as compared with groups B and C, PO2 levels in group A were significantly reduced.Similar results could be observed in PAwP values, but the tendency was increasing.(2) The level of W/D, MPO activity, MDA content, and the mRNA expression of IL-8 and ICAM-1 in groups B and C were decreased as

  6. Use of beat-to-beat cardiovascular variability data to determine the validity of sham therapy as the placebo control in osteopathic manipulative medicine research.

    Science.gov (United States)

    Henley, Charles E; Wilson, Thad E

    2014-11-01

    Osteopathic manipulative medicine researchers often use sham therapy as the placebo control during clinical trials. Optimally, the sham therapy should be a hands-on procedure that is perceptually indistinguishable from osteopathic manipulative treatment, does not create an effect on its own, and is not a treatment intervention. However, the sham therapy itself may often influence the outcome. The use of cardiovascular variability (eg, beat-to-beat heart rate variability) as a surrogate for the autonomic nervous system is one objective method by which to identify such an effect. By monitoring cardiovascular variability, investigators can assess autonomic nervous system activity as a response to the sham therapy and quickly determine whether or not the selected sham therapy is a true placebo control. The authors provide evidence for assessment of beat-to-beat heart rate variability as one method for assuring objectivity of sham therapy as a placebo control in osteopathic manipulative medicine research.

  7. Value of evaluating diastolic function with the single-beat E/(e’ × s) obtained by dual doppler echocardiograph in coronary heart disease patients with preserved left ventricular systolic function

    Institute of Scientific and Technical Information of China (English)

    汪晶晶

    2014-01-01

    Objective To assess the value of E/(e’×s)in estimating left ventricular diastolic dysfunction in patients with coronary heart disease by dual Doppler echocardiograph.Methods Seventy-seven consecutive coronary heart disease patients with preserved systolic function underwent echocardiographic study were included.The E,e’and s were obtained by the dual Doppler echocardio-

  8. 机器人非体外循环冠状动脉旁路移植与支架置入"杂交"手术治疗多支冠状动脉病变%Treatment of multiple vessel coronary artery diseaseby robotic bypass surgery on the beating heart and stent placement in distinct hybrid session

    Institute of Scientific and Technical Information of China (English)

    高长青; 杨明; 吴扬; 王刚; 肖苍松; 王加利; 李丽霞; 赵悦; 周琪

    2011-01-01

    目的 总结达芬奇S机器人系统行非体外循环冠状动脉旁路移植与支架置入"杂交"手术治疗多支冠状动脉病变的技术特点和优势.方法 2007年至2011年,使用da Vinic S全机器人系统完成非体外循环冠状动脉旁路移植术163例,其中12例患者因两支或三支冠状动脉病变,在机器人手术后行分站式支架置入术.男9例,女3例;年龄(56.0±9.7)岁;均有心绞痛症状,冠状动脉造影显示严重的前降支或对角支病变,合并回旋支或右冠状动脉的病变;4例有心肌梗死病史.先对所有患者前降支病变行机器人非体外循环下冠状动脉旁路移植术,术后待患者恢复平稳再行其他病变冠状动脉支架置入术.冠状动脉造影评价在再血管化效果.结果 所有患者均成功接受机器人非体外循环冠状动脉旁路移植术,术后恢复顺利,随后成功接受支架置入术.全组无并发症.结论 机器人非体外循环冠状动脉旁路移植和支架置入"杂交"手术可最大限度的减小手术创伤并实现冠状动脉完全再血管化.%Objective Summary the first group of robotic bypass surgery on the beating heart and stent placement in distinct hybrid session in China. Methods 163 cases patients accepted selective operation of robotic coronary bypass grafting on the beating heart form April 2007 to January 2011. 12 cases had multi coronary vessels stenosis accepted stent placement after robotic surgery in a hybrid manner. The average age of patients was ( 56. 0 ± 9.74 ) years old. 3 case was female and 9 cases were male. All the patients had a medical history of angina. The coronary arterioangiography showed sever left anterior descend ing or diagonal branch stenosis in all patients. And 4 cases had myocardial infarction history. All the patients had good lung function and had no medical history of pleurisy. Without sternotomy, through 3 ports about 1 cm in left thorax, the left internal mammary artery was obtained

  9. Burkitt Lymphoma Presenting as an Intracardiac Mass: Case Report and Review of Literature.

    Science.gov (United States)

    Chan, Onyee; Igwe, Michael; Breburda, Christian S; Amar, Surabhi

    2016-01-01

    BACKGROUND Non-neoplastic causes such as infections and thrombi account for most intracardiac masses. Primary tumors such as myxomas and metastasis from breast cancer, lung cancer, or melanomas account for many of the remaining cases. Burkitt lymphoma manifesting as an intracardiac mass is a rare entity, with 21 cases reported in the English literature. CASE REPORT We report the case of a man infected with human immunodeficiency virus (HIV) who presented with non-specific cardiac symptoms and was later found to have intracardiac mass caused by Burkitt lymphoma. His rapid decline with unexpected complications was reversed with prompt management. Subsequent to induction, the patient achieved a near complete response with considerable improvement in his condition. CONCLUSIONS Lymphoma should be considered in the differential diagnosis of intracardiac masses. Associated cardiac symptoms are frequently non-specific and can often be overlooked or underappreciated. Burkitt lymphoma has a short doubling time and an intracardiac lesion can become life-threatening in a matter of days. Early recognition and prompt treatment are crucial to achieving optimal outcomes. PMID:27484990

  10. Progressive pulmonary hypertension in cyanotic congenital heart disease with severe pulmonary stenosis

    OpenAIRE

    Cheung, YF; Leung, MP; Wang, EP

    1996-01-01

    We report the progressive development of pulmonary hypertension despite the presence of severe pulmonary stenosis in three patients with cyanotic congenital heart disease. The associated intracardiac lesions were complete transposition with a ventricular septal defect, double outlet right ventricle, and a heart with univentricular atrioventricular connection, respectively. Serial measurements on hemodynamics andhistological findings documented the progression of pulmonary hypertension and pul...

  11. Beat Subterranean: Tactics of Assemblage and Worldmaking in Beat Generation Writing

    OpenAIRE

    Fazzino, Jimmy Michael

    2012-01-01

    My dissertation argues that the core beat trope of the subterranean can be developed as a productive means of literary analysis. I show that beat writers conceive of themselves and their work as existing within vast "underground" networks of radical and avant-garde art and literature, and by locating the beats within such assemblages, the subterranean offers, above all, a model for reconceptualizing beat geography. While the Beat Generation has been regarded as quintessentially American, beat...

  12. Behcet’s Disease with Intracardiac Thrombus Presenting with Fever of Unknown Etiology

    Directory of Open Access Journals (Sweden)

    Sajal Ajmani

    2015-01-01

    Full Text Available A young male was referred to us for evaluation of fever of unknown origin (FUO. He had history of recurrent painful oral ulcers for one year and moderate to high grade fever, pustulopapular rash, and recurrent genital ulcers for 6 months and hemoptysis for 3 days. He was detected to have intracardiac thrombi and pulmonary arterial thrombosis along with underlying Behcet’s disease (BD. Patient responded to high dose prednisolone (1 mg/Kg/day along with monthly parenteral cyclophosphamide therapy. This case highlights the fact that BD is an important cause for pulmonary artery vasculitis with intracardiac thrombus formation, and such patients can present with FUO.

  13. Stochastic Alternating Dynamics for Synchronous EAD-Like Beating Rhythms in Cultured Cardiac Myocytes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ning; ZHANG Hui-Min; LIU Zhi-Qiang; DING Xue-Li; YANG Ming-Hao; GU Hua-Guang; REN Wei

    2009-01-01

    Dissolved cardiac myocytes can couple together and generate synchronous beatings in culture. We observed a synchronized early after-depolarization(EAD)-like rhythm in cultured cardiac myocytes and reproduced the experimental observation in a network mathematical model whose dynamics are close to a Hopf bifurcation. The mechanism for this EAD-like rhythm is attributed to noised-induced stochastic alternatings between the focus and the limit cycle. These results provide novel understandings for pathological heart rhythms like the early immature beatings.

  14. Doppler Beats or Interference Fringes?

    Science.gov (United States)

    Kelly, Paul S.

    1979-01-01

    Discusses the following: another version of Doppler beats; alternate proof of spin-1 sin-1/2 problems; some mechanisms related to Dirac's strings; Doppler redshift in oblique approach of source and observer; undergraduate experiment on noise thermometry; use of the time evolution operator; resolution of an entropy maximization controversy;…

  15. Musicians' Perception of Beat in Monotonic Stimuli.

    Science.gov (United States)

    Duke, Robert A.

    1989-01-01

    Assesses musicians' perceptions of beat in monotonic stimuli and attempts to define empirically the range of perceived beat tempo in music. Subjects performed a metric pulse in response to periodic stimulus tones. Results indicate a relatively narrow range within which beats are perceived by trained musicians. (LS)

  16. Signal processing of Shiley heart valve data for fracture detection

    Energy Technology Data Exchange (ETDEWEB)

    Mullenhoff, C.

    1993-09-01

    Given digital acoustic data emanating from the heart sounds of the beating heart measured from laboratory sheep with implanted Bjoerk-Shiley Convexo-Concave heart valves, it is possible to detect and extract the opening and closing heart beats from the data. Once extracted, spectral or other information can then obtained from the heartbeats and passed on to feature extraction algorithms, neural networks, or pattern recognizers so that the valve condition, either fractured or intact, may be determined.

  17. Signal processing of Shiley heart valve data for fracture detection

    Energy Technology Data Exchange (ETDEWEB)

    Mullenhoff, C.

    1993-04-01

    Given digital acoustic data emanating from the heart sounds of the beating heart measured from laboratory sheep with implanted Bjoerk-Shiley Convexo-Concave heart valves, it is possible to detect and extract the opening and closing heart beats from the data. Once extracted, spectral or other information can then obtained from the heartbeats and passed on to feature extraction algorithms, neutral networks, or pattern recognizers so that the valve condition, either fractured or intact, may be determined.

  18. 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.

  19. Beat-to-beat analysis method for magnetocardiographic recordings during interventions

    International Nuclear Information System (INIS)

    Multichannel magnetocardiography (MCG) during exercise testing has been shown to detect myocardial ischaemia in patients with coronary artery disease. Previous studies on exercise MCG have focused on one or few time intervals during the recovery period and only a fragment of the data available has been utilized. We present a method for beat-to-beat analysis and parametrization of the MCG signal. The method can be used for studying and quantifying the changes induced in the MCG by interventions. We test the method with data recorded in bicycle exercise testing in healthy volunteers and patients with coronary artery disease. Information in all cardiac cycles recorded during the recovery period of exercise MCG testing is, for the first time, utilized in the signal analysis. Exercise-induced myocardial ischaemia was detected by heart rate adjustment of change in magnetic field map orientation. In addition to the ST segment, the T wave in the MCG was also found to provide information related to myocardial ischaemia. The method of analysis efficiently utilizes the spatial and temporal properties of multichannel MCG mapping, providing a new tool for detecting and quantifying fast phenomena during interventional MCG studies. The method can also be applied to an on-line analysis of MCG data. (author)

  20. Abstract Possible: The Birmingham Beat

    OpenAIRE

    Bergman, Aeron; Salinas, Alejandra

    2013-01-01

    Gruppeutstilling. Samarbeidspartner: Alejandra Salinas. ABSTRACT YOUR SHIT IS Video loop and billboard. Eastside Projects, Birmingham UK Abstract Possible: The Birmingham Beat Curated by Maria Lind 6 October - 1 December 2012. Invited artists: José León Cerrillo, Zachary Formwalt, Goldin+Senneby, Wade Guyton, Yelena Popova, Alejandra Salinas and Aeron Bergman. Visningssted: Eastside Projects, Birmingham, UK. Se også: http://eastsideprojects.org/past/abstract-possible

  1. Beating phantasies: Mourned and unmourned.

    Science.gov (United States)

    Antinucci, Giuseppina

    2016-06-01

    This paper intends to explore the organizing function and fate of sado-masochistic phantasies in their fixed form, in the psychic life of patients who have suffered early traumas, due to environmental vicissitudes and maternal psychopathology. The theoretical starting point is provided by the Novicks' research into transitory and permanent beating phantasies in adult and child patients, their onset and their psychic function, based on an examination of Freud's paper 'A child is being beaten'. In this text Freud achieves an unprecedented syncretism, locating the phantasy at the intersection between the oedipal complex, which is a vertical structure organizing sexual and generational differences, and the fraternal dimension, which is horizontal and organizes the lateral relationship with that similar but different other who is the sibling. Reporting in some detail material from the analyses of two young women, whose clinical presentation and early traumas show some similarities, the author puts in the context of the analytic work the emerging of the sado-masochistic phantasies, emphasizing their use and function in the transference-countertransference interplay. The beating phantasies shore up a precarious sense of self, threatened with psychic depletion and death, in identification with the absent mother of early infancy. An overly close relationship with a sibling, experienced as a narcissistic double, compounds the clinical picture, to establish the triangle formed by the parent(s) and two children which features in the beating phantasy. Finally, the author explores the contribution of ameliorating factors, such as alternative identificatory figures, constitutional endowment and capacity for sublimation, to account for the different fate of the fixed beating phantasies. PMID:26602362

  2. Plasma Beat-Wave Acceleration

    Science.gov (United States)

    Clayton, Christopher E.

    2002-04-01

    Among all the advanced accelerator concepts that use lasers as the power source, most of the effort to date has been with the idea of using a laser pulse to excite a accelerating mode in a plasma. Within this area, there are a variety of approaches for creating the accelerating mode, as indicated by the other talks in this session. What is common to these approaches is the physics of how a laser pulse pushes on plasma electrons to organize electron-density perturbations, the sources of the ultra-high (> GeV/M) accelerating gradients. It is the "ponderomotive force", proportional to the local gradient of the of the laser intensity, that pushes plasma electrons forward (on the leading edge of the pulse) and backwards (on the trailing edge) which leads to harmonic motion of the electrons. As the laser pulse moves through the plasma at group velocity Vg c, the oscillating electrons show up macroscopically as a plasma mode or wave with frequency w equal to the plasma frequency and k = w/Vg. For short laser pulses, this is the Laser Wakefield Accelerator (LWFA) concept. Closely related is the Plasma Beat-Wave Acceleration (PBWA) concept. Here, the laser pulse that perturbs the plasma is composed of two closely-spaced frequencies that "beat", i.e., periodically constructively and destructively interfere, forming an electromagnetic beat wave. One can visualize this as a train of short pulses. If this beating frequency is set to the plasma frequency, then each pulse in the train will reinforce the density perturbation caused by the previous pulse. The principal advantage of multiple pulses driving up the plasma wave as opposed to a single pulse is in efficiency, allowing for the production of relatively large diameter (more 1-D like) accelerating modes. In this talk I will discuss past, current and planned PBWA experiments which are taking place at UCLA, RAL in England, and LULI in France.

  3. Quantum-beat Auger spectroscopy

    CERN Document Server

    Zhang, Song Bin

    2015-01-01

    The concept of nonlinear quantum-beat pump-probe Auger spectroscopy is introduced by discussing a relatively simple four-level model system. We consider a coherent wave packet involving two low-lying states that was prepared by an appropriate pump pulse. This wave packet is subsequently probed by a weak, time-delayed probe pulse with nearly resonant coupling to a core-excited state of the atomic or molecular system. The resonant Auger spectra are then studied as a function of the duration of the probe pulse and the time delay. With a bandwidth of the probe pulse approaching the energy spread of the wave packet, the Auger yields and spectra show quantum beats as a function of pump-probe delay. An analytic theory for the quantum-beat Auger spectroscopy will be presented, which allows for the reconstruction of the wave packet by analyzing the delaydependent Auger spectra. The possibility of extending this method to a more complex manifold of electronic and vibrational energy levels is also discussed.

  4. An alien in the heart.

    Science.gov (United States)

    Agrawal, Yashwant; Kalavakunta, Jagadeesh K; Gupta, Vishal

    2016-07-01

    We report a case of a 38-year-old-man who presented with altered mental status. The patient was diagnosed with infective endocarditis (IE) originating from the GORE HELEX septal occluder device, which was placed 15 months earlier for symptomatic atrial septal defect. Brain imaging revealed shower emboli phenomena from the known IE. The patient developed hydrocephalus for which external ventriculostomy was performed. Improved neurological status warranted open heart surgery. The patient was later confirmed to be an intravenous drugs abuser, prejudicing IE. This case highlights the importance of meticulously monitoring patients with suspected high-risk behavior with an implanted intracardiac prosthetic device. PMID:27358534

  5. 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

    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 ni...... 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....

  6. Losing the beat: deficits in temporal coordination

    Science.gov (United States)

    Palmer, Caroline; Lidji, Pascale; Peretz, Isabelle

    2014-01-01

    Tapping or clapping to an auditory beat, an easy task for most individuals, reveals precise temporal synchronization with auditory patterns such as music, even in the presence of temporal fluctuations. Most models of beat-tracking rely on the theoretical concept of pulse: a perceived regular beat generated by an internal oscillation that forms the foundation of entrainment abilities. Although tapping to the beat is a natural sensorimotor activity for most individuals, not everyone can track an auditory beat. Recently, the case of Mathieu was documented (Phillips-Silver et al. 2011 Neuropsychologia 49, 961–969. (doi:10.1016/j.neuropsychologia.2011.02.002)). Mathieu presented himself as having difficulty following a beat and exhibited synchronization failures. We examined beat-tracking in normal control participants, Mathieu, and a second beat-deaf individual, who tapped with an auditory metronome in which unpredictable perturbations were introduced to disrupt entrainment. Both beat-deaf cases exhibited failures in error correction in response to the perturbation task while exhibiting normal spontaneous motor tempi (in the absence of an auditory stimulus), supporting a deficit specific to perception–action coupling. A damped harmonic oscillator model was applied to the temporal adaptation responses; the model's parameters of relaxation time and endogenous frequency accounted for differences between the beat-deaf cases as well as the control group individuals. PMID:25385783

  7. Intracardiac tuberculomas caused by Mycobacterium tuberculosis in a dog

    OpenAIRE

    Szaluś-Jordanow, Olga; Augustynowicz-Kopeć, Ewa; Czopowicz, Michał; Olkowski, Arkadiusz; Łobaczewski, Andrzej; RZEWUSKA, Magdalena; Sapierzyński, Rafał; Wiatr, Elżbieta; Garncarz, Magdalena; Frymus, Tadeusz

    2016-01-01

    Background This paper presents an unusual form of disseminated Mycobacterium tuberculosis infection in a dog. The infection lasted at least one year and its main gross lesions were massive cardiac tuberculomas. To the best of our knowledge, this is the first report of heart tuberculomas in a dog. Case presentation A 9-year-old mixed-breed male dog weighing 10 kg was referred to the clinic for cardiological evaluation before general anesthesia. The echocardiography revealed a lump of about 20 ...

  8. Prolonged Intraoperative Cardiac Resuscitation Complicated by Intracardiac Thrombus in a Patient Undergoing Orthotopic Liver Transplantation.

    Science.gov (United States)

    Kim, Sang; DeMaria, Samuel; Cohen, Edmond; Silvay, George; Zerillo, Jeron

    2016-09-01

    We report the case of successful resuscitation after prolonged cardiac arrest during orthotopic liver transplantation. After reperfusion, the patient developed ventricular tachycardia, complicated by intracardiac clot formation and massive hemorrhage. Transesophageal echocardiography demonstrated stunned and nonfunctioning right and left ventricles, with developing intracardiac clots. Treatment with heparin, massive transfusion and prolonged cardiopulmonary resuscitation ensued for 51 minutes. Serial arterial blood gases demonstrated adequate oxygenation and ventilation during cardiopulmonary resuscitation. Cardiothoracic surgery was consulted for potential use of extracorporeal membrane oxygenation, however, the myocardial function improved and the surgery was completed without further intervention. On postoperative day 6, the patient was extubated without neurologic or cardiac impairment. The patient continues to do well 2 years posttransplant, able to perform independent daily activities of living and his previous job. This case underscores the potential for positive outcomes with profoundly prolonged, effective advanced cardiovascular life support in patients who experience postreperfusion syndrome. PMID:27233818

  9. Transesophageal echocardiography-guided thrombectomy of intracardiac renal cell carcinoma without cardiopulmonary bypass

    Science.gov (United States)

    Souki, Fouad Ghazi; Demos, Michael; Fermin, Lilibeth; Ciancio, Gaetano

    2016-01-01

    Advanced renal cell carcinoma (RCC) resection has important anesthetic management implications, particularly when tumor extends, suprahepatic, into the right atrium. Use of transesophageal echocardiogram (TEE) is essential in identifying tumor extension and guiding resection. Latest surgical approach avoids venovenous and cardiopulmonary bypass yet requires special precautions and interventions on the anesthesiologist's part. We present a case of Level IV RCC resected without cardiopulmonary bypass and salvaged by TEE guidance and detection of residual intracardiac tumor. PMID:27716710

  10. 人工虫草复合液对无心跳模型大鼠离体肾的低温保护作用%Protective effect at low temperature of artificial cordyceps compound on isolated kidney from non-heart-beating rat models

    Institute of Scientific and Technical Information of China (English)

    戴晨; 王顺; 徐加波; 刘健

    2016-01-01

    背景:无心跳供体已成为近年来最有潜力的移植供体来源,为进一步改进供体保存液,在常规保存液高渗枸橼酸盐腺嘌呤液的基础上加入人工虫草制备人工虫草复合液,希望通过其抗氧化作用,减少供体损伤,提高供体质量。目的:探讨人工虫草复合液对无心跳大鼠离体肾的保存作用。方法:将39只SD大鼠毁损延髓,不进行体外呼吸循环支持,造成脑死亡诱导的无心跳模型后,随机等分为3组,人工虫草复合液组(n=15)、高渗枸橼酸盐腺嘌呤液组(n=15)和生理盐水组(n=9),分别用人工虫草复合液、高渗枸橼酸盐腺嘌呤液、生理盐水对离体肾脏进行4℃低温保存。结果与结论:与高渗枸橼酸盐腺嘌呤液组相比,人工虫草复合液组肾组织保存6和12 h后,形态损伤较轻,凋亡指数、丙二醛含量、Bax及Caspase-3表达水平下降,超氧化物歧化酶活力及Bcl-2表达水平上升;而保存24 h后,形态损伤程度接近,丙二醛含量下降,超氧化物歧化酶活力上升。提示人工虫草复合液对无心跳大鼠离体肾的抗氧化、抑制细胞凋亡方面保存效果优于高渗枸橼酸盐腺嘌呤液。%BACKGROUND:Non-heart beating donors have become the most promising source of donor in recent years. Tofurther improve donor preservation solution, on the basis of conventional storage solution hypertonic citrate adenine solution, artificial cordyceps was added to prepare artificial cordyceps compound solution. It is hoped to reduce donor injury and to elevate donor quality by antioxidation. OBJECTIVE: To investigate the preservation effect of artificial cordyceps compound solution on isolated renal from non-heart-beating rats. METHODS: Medulas of 39 Sprague-Dawley rats were injured. Withoutin vitro respiratory and circulatory supports, non-heart-beating models were established and randomly divided into three groups: artificial cordyceps

  11. Bondage fantasies and beating fantasies.

    Science.gov (United States)

    Weiss, J

    1998-10-01

    Two male patients had masochistic sexual fantasies: one had bondage fantasies, the other beating fantasies. Each patient had been traumatized in childhood by his experiences with a martyr mother. Each had developed the belief that in an intimate sexual relationship with a woman he would hurt her. As a consequence, each tended to suppress his sexuality. Each used masochistic fantasies to reassure himself that he was not hurting his fantasied or real partner. The reassurance made it safe to experience his sexual feelings. The two patients' use of their masochistic fantasies is compared to the fetishist's use of his fetish, as described by Freud. PMID:9820894

  12. [Cholinergic system of the heart].

    Science.gov (United States)

    Kučera, Matej; Hrabovská, Anna

    2015-12-01

    The cholinergic system of the heart can be either of neuronal or non-neuronal origin. The neuronal cholinergic system in the heart is represented by preganglionic parasympathetic pathways, intracardiac parasympathetic ganglia and postganglionic parasympathetic neurons projecting to the atria, SA node and AV node. The non-neuronal cholinergic system consists of cardiomyocytes that have complete equipment for synthesis and secretion of acetylcholine. Current knowledge suggests that the non-neuronal cholinergic system in the heart affects the regulation of the heart during sympathetic activation. The non-neuronal cholinergic system of the heart plays also a role in the energy metabolism of cardimyocites. Acetylcholine of both neuronal and non-neuronal origin acts in the heart through muscarinic and nicotinic receptors. The effect of acetylcholine in the heart is terminated by cholinesterases acetylcholinesterase and butyrylcholinesterase. Recently, papers suggest that the increased cholinergic tone in the heart by cholinesterase inhibitors has a positive effect on some cardiovascular disorders such as heart failure. For this reason, the cholinesterase inhibitors might be used in the treatment of certain cardiovascular disorders in the future.

  13. Rare Intracardiac Tumor: Primary Cardiac Lymphoma Presenting as Atypical Angina

    Directory of Open Access Journals (Sweden)

    Karthigesu Aimanan

    2016-01-01

    Full Text Available Primary lymphomas of the heart are extremely rare, accounting for 2% of all primary cardiac tumors. Due to the rare presentation, there is no proper consensus available on treatment strategy. Preoperative confirmation of the pathology is fundamental in guiding an early treatment plan, which allows for improved prognosis. Unfortunately, in most cases, primary cardiac lymphoma is only identified on postoperative histopathological analyses, which affect the treatment plan and outcome. Here, we report a unique case of primary cardiac lymphoma presented with dyspnea and reduced effort tolerance. Young age, rapid onset of symptom, and absence of cardiac risk factors prompted us towards further imaging and emergency resection. The patient received a course of postoperative chemotherapy and was disease-free on six months of follow-up.

  14. Detection and removal of ventricular ectopic beats in atrial fibrillation recordings via principal component analysis.

    Science.gov (United States)

    Martínez, Arturo; Alcaraz, Raúl; Rieta, José J

    2011-01-01

    Ectopic beats are early heart beats with remarkable large amplitude that provoke serious disturbances in the analysis of electrocardiograms (ECG). These beats are very common in atrial fibrillation (AF) and are the source of important residua when the QRST is intended to be removed. Given that QRST cancellation is a binding step in the appropriate analysis of atrial activity (AA) in AF, a method for ventricular ectopic beats cancellation is proposed as a previous step to the application of any QRST removal technique. First, the method discriminates between normal and ectopic beats with an accuracy higher than 99% through QRS morphological characterization. Next, the most similar ectopic beats to the one under cancellation are clustered and serve to get their eigenvector matrix by principal component analysis. Finally, the highest variance eigenvector is used as cancellation template. The reduction ectopic rate (RER) has been defined to evaluate the method's performance by using templates generated with 5, 10, 20, 40 or 80 ectopics. Optimal results were reached with the 5 most similar complexes, yielding a RER higher than 5.5. In addition, a decreasing RER trend was noticed as the number of considered ectopics for cancellation increased. As conclusion, given that ectopics presented a remarkable variability in their morphology, the proposed cancellation approach is a robust ectopic remover and can notably facilitate the later application of any QRST cancellation technique to extract the AA in the best conditions. PMID:22255385

  15. 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...

  16. 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.

  17. Possible instabilities in the beat wave accelerator

    International Nuclear Information System (INIS)

    In this article the concept of the beat wave accelerator is studied with emphasis put on the plasma physics. An important effect is the relativistic nature of the electrons oscillating in the electric field of the beat wave. Various instabilities are presented which could limit the overall efficiency of the accelerating process. (author)

  18. ANSWER: A tapping apex beat

    OpenAIRE

    Nazar LUQMAN

    2012-01-01

    (Refer to page 253)Answer: Mitral valve stenosis (Doming of mitral leaflets)The mitral valve is frequently involved in rheumatic heart disease, which is still prevalent in developing countries. Other valves may also be involved. The incidence of rheumatic heart disease is now less common in developed and developing nations. It is notinfrequently encountered in Brunei Darussalam. The mitral valve is usually affected decades following an episode of rheumatic carditis. With time, the rheumatic h...

  19. Elastic interactions synchronize beating in cardiomyocytes.

    Science.gov (United States)

    Cohen, Ohad; Safran, Samuel A

    2016-07-13

    Motivated by recent experimental results, we study theoretically the synchronization of the beating phase and frequency of two nearby cardiomyocyte cells. Each cell is represented as an oscillating force dipole in an infinite, viscoelastic medium and the propagation of the elastic signal within the medium is predicted. We examine the steady-state beating of two nearby cells, and show that elastic interactions result in forces that synchronize the phase and frequency of beating in a manner that depends on their mutual orientation. The theory predicts both in-phase and anti-phase steady-state beating depending on the relative cell orientations, as well as how synchronized beating varies with substrate elasticity and the inter-cell distance. These results suggest how mechanics plays a role in cardiac efficiency, and may be relevant for the design of cardiomyocyte based micro devices and other biomedical applications. PMID:27352146

  20. Ventilation with low-dose carbon monoxide protects non-heart-beating donor rat lungs against worm ischemic injury%低浓度一氧化碳通气减轻无心跳供体肺的热缺血损伤

    Institute of Scientific and Technical Information of China (English)

    陈乾坤; 姜格宁; 谢博雄; 丁嘉安; 陈晓峰

    2008-01-01

    Objective This study investigated the preservative effect of ventilation with low-dose carbon monoxide during warmischemia in non-heart-beating donor rat lungs. Methods Twelve animals were divided into a CO group (n = 6) , which received ven-tilation with low-dose carbon monoxide during a 4-hour warm ischemic period, and a control group (n = 6), which received no ventila-tion. PaO2, myeloperoxidase(MPO)activity, bronchoalveolar lavage (BAL) neutrophil count and the wet-to-dry (W/D) lung weightratio were recorded in each group. Results At the time point of 1 hour, 2 hours and 4 hours reperfusion, PaO2 in control group weresignificantly lower than CO group [(270±70) mm Hg vs. (400±80) mm Hg, (210±50) mm Hg vs. (320±60) mm Hg, (160±40) mm Hg vs. (250±55) mm Hg, P <0.05]. After 4 hours reperfusion, the W/D lung weight ratio in control group was signifi-cantly higher than CO group ( 7.3±0.5 vs. 5.4±0.8, P = 0.06 ). MPO activity in control group were significantly higher than inCO group (0.46±0.05 vs.0.27±0.06, P=0.015). BAL neutrophil count in control group was much higher than in CO group[(132±37)×105 vs. (97±28)×105, P < 0.05 ]. Expression of IL-1β mRNA in CO group was significantly lower than in controlgroup (0.435±0.221 vs. 0.592±0.121, P <0.05). Expression of caspase 3 mRNA in CO group were obviously lower than incontrol group (0.412±0.132 vs. 0.613±0.104, P<0.05). Conclusion Ventilation with low-dose monoxise can protectnon-heart-beating donor rat lungs againt warm ischemic injury by inhibiting the expression of proimflammatory factor IL-1β and apopto-sis-associated gene caspase 3. Ventilation with low-dose carbon monoxide presents a new strategy for the protection of lung graft in non-heart-beating donors.%目的 探讨低浓度一氧化碳通气对无心跳供体(NHBD)移植肺组织的热缺血损伤保护机制.方法 对供体大鼠NHBD给予低浓度CO机械通气,利用大鼠左肺移植动物模型进行研究;再灌注后测定动脉

  1. Estimation of heart rate and heart rate variability from pulse oximeter recordings using localized model fitting.

    Science.gov (United States)

    Wadehn, Federico; Carnal, David; Loeliger, Hans-Andrea

    2015-08-01

    Heart rate variability is one of the key parameters for assessing the health status of a subject's cardiovascular system. This paper presents a local model fitting algorithm used for finding single heart beats in photoplethysmogram recordings. The local fit of exponentially decaying cosines of frequencies within the physiological range is used to detect the presence of a heart beat. Using 42 subjects from the CapnoBase database, the average heart rate error was 0.16 BPM and the standard deviation of the absolute estimation error was 0.24 BPM. PMID:26737125

  2. In vitro culture of embryonic hearts from guppy fish (Poecilia reticulata )

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Forty embryonic hearts were taken out byanatomical needle from denuded embryos of the ovovivipar ity guppy fish that were dechorioned by mechanic method or by trypsin digestion, and were in vitro cultured. In the cul tured hearts, 80% have maintained beating in vitro for 4weeks, and the longest record for beating was 142 d. Owing to fish embryo transparency, beating frequency and blood color changes are easily viewed from the embryonic hearts under a dissecting microscope. The current study established the in vitro culture method of embryonic hearts in guppy fish,which can be used as a model for the study of heart and car diovascular system in vertebrates.

  3. Hypoplastic Right-Heart Syndrome Presenting as Multiple Miscarriages

    OpenAIRE

    Dib, Chadi; Araoz, Philip A; Davies, Norman P.; Joseph A Dearani; Naser M. Ammash

    2012-01-01

    Reversible causes of miscarriage are many, but they affect only 1% of women who are trying to conceive. Herein, we describe the case of a 23-year-old woman who presented for evaluation of repeated miscarriages and was found to have hypoxemia and erythrocytosis. Further evaluation revealed hypoplastic right-heart syndrome with an intracardiac shunt. She underwent hybrid repair with pulmonary valve balloon valvuloplasty, followed by surgery to perform atrial septal defect closure and a Glenn an...

  4. Cardiac Extracellular Vesicles in Normal and Infarcted Heart

    OpenAIRE

    Chistiakov, Dimitry A.; Alexander N. Orekhov; Yuri V Bobryshev

    2016-01-01

    Heart is a complex assembly of many cell types constituting myocardium, endocardium and epicardium that intensively communicate to each other in order to maintain the proper cardiac function. There are many types of intercellular intracardiac signals, with a prominent role of extracellular vesicles (EVs), such as exosomes and microvesicles, for long-distant delivering of complex messages. Cardiomyocytes release EVs, whose content could significantly vary depending on the stimulus. In stress, ...

  5. 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.

  6. Intracardiac echocardiography guided transeptal catheter injection of microspheres for assessment of cerebral microcirculation in experimental models.

    Science.gov (United States)

    Bellapart, Judith; Dunster, Kimble R; Diab, Sara; Platts, David G; Raffel, Christopher; Gabrielian, Levon; Maybauer, Marc O; Barnett, Adrian; Boots, Robert James; Fraser, John F

    2013-01-01

    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.

  7. 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

  8. 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.

  9. 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.

  10. On the beating of reinforcement pulp

    OpenAIRE

    Hiltunen, Eero

    2003-01-01

    The aim of this work was to gain a better understanding of the effect of reinforcement pulp beating on the strength of mechanical pulp-dominated paper. The main purpose of reinforcement pulp beating is to improve the runnability of paper. The first objective of this study was to maximize the runnability related strength properties by beating. It was assumed that the flaw-resisting ability of paper correlates with the runnability of the dry paper web. In-plane fracture properties were assumed ...

  11. Substrate stiffness-modulated registry phase correlations in cardiomyocytes map structural order to coherent beating

    Science.gov (United States)

    Dasbiswas, K.; Majkut, S.; Discher, D. E.; Safran, Samuel A.

    2015-01-01

    Recent experiments show that both striation, an indication of the structural registry in muscle fibres, as well as the contractile strains produced by beating cardiac muscle cells can be optimized by substrate stiffness. Here we show theoretically how the substrate rigidity dependence of the registry data can be mapped onto that of the strain measurements. We express the elasticity-mediated structural registry as a phase-order parameter using a statistical physics approach that takes the noise and disorder inherent in biological systems into account. By assuming that structurally registered myofibrils also tend to beat in phase, we explain the observed dependence of both striation and strain measurements of cardiomyocytes on substrate stiffness in a unified manner. The agreement of our ideas with experiment suggests that the correlated beating of heart cells may be limited by the structural order of the myofibrils, which in turn is regulated by their elastic environment.

  12. A Case of Myopathy, Encephalopathy, Lactic Acidosis and Stroke-Like Episodes (MELAS) Syndrome with Intracardiac Thrombus [corrected].

    Science.gov (United States)

    Joo, Jung-Chul; Seol, Myung Do; Yoon, Jin Won; Lee, Young Soo; Kim, Dong-Keun; Choi, Yong Hoon; Ahn, Hyo Seong; Cho, Wook Hyun

    2013-03-01

    Myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) is a multisystem clinical syndrome manifested by mitochondrial myopathy, encephalopathy, lactic acidosis and recurrent stroke-like episodes. A 27-year-old female with MELAS syndrome presented with cerebral infarction. Echocardiography revealed a thrombus attached to the apex of the hypertrophied left ventricle, with decreased systolic function. The embolism of the intracardiac thrombus might have been the cause of stroke. There should be more consideration given to the increased possibility of intracardiac thrombus formation when a MELAS patient with cardiac involvement is encountered.

  13. Visualizing acoustical beats with a smartphones

    CERN Document Server

    Giménez, Marcos H; Castro-Palacio, Juan C; Gómez-Tejedor, José A; Monsoriu, Juan A

    2016-01-01

    In this work, a new Physics laboratory experiment on Acoustics beats is presented. We have designed a simple experimental setup to study superposition of sound waves of slightly different frequencies (acoustic beat). The microphone of a smartphone is used to capture the sound waves emitted by two equidistant speakers from the mobile which are at the same time connected to two AC generators. The smartphone is used as a measuring instrument. By means of a simple and free AndroidTM application, the sound level (in dB) as a function of time is measured and exported to a .csv format file. Applying common graphing analysis and a fitting procedure, the frequency of the beat is obtained. The beat frequencies as obtained from the smartphone data are compared with the difference of the frequencies set at the AC generator. A very good agreement is obtained being the percentage discrepancies within 1 %.

  14. Early intracardiac thrombosis in preterm infants and thrombolysis with recombinant tissue type plasminogen activator

    Science.gov (United States)

    Ferrari, F; Vagnarelli, F; Gargano, G; Roversi, M; Biagioni, O; Ranzi, A; Cavazzuti, G

    2001-01-01

    OBJECTIVES—To determine the incidence of catheter related thrombosis and to test the efficacy of recombinant tissue type plasminogen activator (rt-PA) in preterm infants.
STUDY DESIGN—From January 1995 to December 1998, echocardiography was performed in the first few days of life in 76 very low birthweight (⩽ 1500 g) infants out of a total of 147 having an umbilical catheter placed. When intracardiac thrombosis was diagnosed, rt-PA infusion was performed.
RESULTS—Four infants (5%) developed an intracardiac thrombosis during the first few days of life. In three of them, rt-PA at a dose of 0.4-0.5 mg/kg in a 20-30 minute bolus led to dissolution of the clot. One patient received a three hour infusion after the bolus, at a dose of 0.1 mg/kg/h, with resolution of the thrombus. No systemic effects were observed after rt-PA infusion.
CONCLUSIONS—Early thrombosis may occur as a complication of umbilical catheterisation in preterm infants; early echocardiographic detection of this disorder allows complete, safe, and rapid lysis with rt-PA.

 PMID:11420328

  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. 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 ...

  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. Repeated gentle handling in beef cattle: heart rate and behaviour

    OpenAIRE

    Schulze Westerath, Heike; Probst, Johanna; Gygox, Lorenz; Hillmann, Edna

    2010-01-01

    A good animal-human relationship is one important aspect concerning cattle welfare. The aim of this study was to investigate the effect of gentle handling at head and neck on behaviour and heart beat parameters in beef cattle.

  19. 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.

  20. Optical Beat-Wave Experiment on CTIX

    Science.gov (United States)

    Horton, Robert; Hwang, David; Liu, Fei; Zhu, Ben; Evans, Russell

    2009-11-01

    By launching intense electromagnetic waves at differing frequencies, a wave at the beat (difference) frequency can be created within a region of plasma. The beat wave is efficiently damped, and electron current generated, if the beat frequency is close to local plasma frequency, and if phase velocity is close to electron thermal velocity. Beat-wave acceleration of plasma electrons was previously demonstrated at low plasma density [1]. At the higher densities of the CTIX compact-toroid accelerator, plasma frequencies are such that CO2 lasers (f 30 THz) are a cost-effective driver. An experiment is being prepared to test beat-wave current drive using two TEA CO2 lasers on CTIX. The experiment will test models of wave mixing, quasilinear modification of the velocity distribution, and amplification of seed current by plasma kinetic effects. An application of the methods developed may be standoff current generation in a target plasma. Experimental issues to be addressed include: precisely-timed production of the compressed, target plasma; grating tuning of the CO2 lasers for frequency selection; high-peak-power, simultaneous operation of TEA lasers, design of optics; optical and plasma diagnostics. Initial results will be presented.[4pt] [1] Rogers, J. H. and Hwang, D. Q., Phys. Rev. Lett. v68 p3877 (1992).

  1. Intermode beat stabilized laser with frequency pulling.

    Science.gov (United States)

    Yokoyama, S; Araki, T; Suzuki, N

    1994-01-20

    A frequency-stabilized two-mode He-Ne laser has been developed. The intermode beat frequency of the experimental laser was approximately 600 MHz for a 25-cm cavity. The laser frequency in which the mode stands is pulled to the center of the gain curve (frequency pulling). The degree of pulling depends on where the longitudinal modes stand in the broadened gain curve. Beat frequency is thereby changed periodically of the order of hundreds of kilohertz with respect to cavity expansion. The frequency pulling was effectively used for frequency stabilization of the laser. The standing position of the longitudinal mode lights was locked in the gain curve by controlling the change of intermode beat frequency. A microwave mixer was applied to extract the frequency change of the intermode beat. Excellent frequency stability (10(10) for the laser oscillation and 10(6) for the beat frequency) was attained. The polarization orthogonality of the proposed laser was superior to that of Zeeman lasers.

  2. Value and limits of the computed tomography of the heart

    International Nuclear Information System (INIS)

    In cardiac diagnosis we can observe an increasing replacement of the conventional invasive examination methods by less invasive or non invasive procedures. Non invasive examination methods are sufficient in the diagnostic work-up of ventricular function in coronary heart disease and cardiomyopathie, cardiac tumours and thrombi, calcifications, assessment of the bypass perfusion, pericardial disease, positional anomalies of the heart and the morphological changes caused by congenital cardiovascular defects. Invasive angiocardiography remains essential in the diagnosis of coronary artery stenoses, abnormal bypass perfusion, septal defects and in congenital cardiovascular defects in combination with intracardiac measurements of pressure and oxygenation. (orig.)

  3. Diuretics as pathogenetic treatment for heart failure

    Directory of Open Access Journals (Sweden)

    Maya Guglin

    2011-01-01

    Full Text Available Maya GuglinUniversity of South Florida, Tampa, FL, USAAbstract: 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.Keywords: heart failure, diuretics, congestion, systolic function, diastolic function, ejection fraction

  4. 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.

  5. 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.

  6. 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 ...

  7. 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

  8. Beat that Word: How Listeners Integrate Beat Gesture and Focus in Multimodal Speech Discourse.

    Science.gov (United States)

    Dimitrova, Diana; Chu, Mingyuan; Wang, Lin; Özyürek, Asli; Hagoort, Peter

    2016-09-01

    Communication is facilitated when listeners allocate their attention to important information (focus) in the message, a process called "information structure." Linguistic cues like the preceding context and pitch accent help listeners to identify focused information. In multimodal communication, relevant information can be emphasized by nonverbal cues like beat gestures, which represent rhythmic nonmeaningful hand movements. Recent studies have found that linguistic and nonverbal attention cues are integrated independently in single sentences. However, it is possible that these two cues interact when information is embedded in context, because context allows listeners to predict what information is important. In an ERP study, we tested this hypothesis and asked listeners to view videos capturing a dialogue. In the critical sentence, focused and nonfocused words were accompanied by beat gestures, grooming hand movements, or no gestures. ERP results showed that focused words are processed more attentively than nonfocused words as reflected in an N1 and P300 component. Hand movements also captured attention and elicited a P300 component. Importantly, beat gesture and focus interacted in a late time window of 600-900 msec relative to target word onset, giving rise to a late positivity when nonfocused words were accompanied by beat gestures. Our results show that listeners integrate beat gesture with the focus of the message and that integration costs arise when beat gesture falls on nonfocused information. This suggests that beat gestures fulfill a unique focusing function in multimodal discourse processing and that they have to be integrated with the information structure of the message.

  9. Preservation of non-heart-beating donor livers by normothermic extracorporeal liver perfusion vs in cold histidine-trytophan-ketoglutarate solution%体外持续肝脏灌注常温保存和HTK液低温保存无心跳供肝效果的比较

    Institute of Scientific and Technical Information of China (English)

    龚瑾; 王西墨; 龙刚; 金中奎; 李国逊; 江涛; 陈实

    2008-01-01

    Objective To compare preservation by the standard method of simple cold storage in HTK solution with that by extracorporeal fiver perfusion.Methods Livers were harvested from health pigs,which were preserved for 10 h by either cold storage in HTK solution (group A,n=4) or by perfusion with oxygenated autologous blood at body temperature (group B,n=4).Both groups were then tested on the circuit for a 4 h reperfusion phase,and the data of bile production,hemodynamic parameters and the markers of hepatoeyte and reperfusion injury of extracorporeal livers in each were analyzed at the end of reperfusion.Results At 1st,2nd,3rd and 4th h after reperfusion,the data of bile production,hemodynamic parameters and the markers of hepatocyte and reperfusion injury of livers in group A were statistically different from those of livers in group B (P<0.05 or P<0.01).Conclusion Compared with simple cold storage in HTK solution,extracorporeal liver perfusion iS a superior method of preservation to non-heart-beating donor livers.%目的 比较应用组氨酸-色氨酸-酮戊二酸(HTK)液低温保存和体外持续肝脏灌注(ECLP)系统常温保存无心跳供肝的效果.方法 按保存方法不同将供肝随机分为A组和B组:供肝切取后,A组用HTK液在低温下保存10 h;B组用ECLP系统在常温下用稀释的自体血液持续灌注10 h.两组供肝再经过60 min冷缺血期后,连接ECLP系统用稀释的自体血液再灌注4 h.观察再灌注后1、2、3、4 h四个时间点的胆汁分泌量,门静脉和肝动脉的压力,肝脏耗氧率的变化,灌注液中丙氨酸转氨酶(ALT)、乳酸脱氢酶(LDH)、葡萄糖水平以及灌注后供肝的常规病理和超微病理变化.结果 B组再灌注后1、2、3、4 h时间点的胆汁分泌量,门静脉和肝动脉的压力,灌注液中ALT、LDH和葡萄糖水平,以及2、3、4 h时间点的耗氧率与A组比较,差异均有统计学意义(P<0.05或P<0.01);B组供肝的病理

  10. 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

  11. 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...

  12. Beat Noise Limitation in Coherent Time-Spreading OCDMA Network

    Institute of Scientific and Technical Information of China (English)

    Ken-ichi; Kitayama; Koji; Mutsushima

    2003-01-01

    The BER performance of the coherent time-spreading OCDMA network is analyzed by considering the MAI and beat noises as well as the other additive noises. The influence and solution for the beat noise issue are discussed.

  13. Heat Beats Cold for Treating Jellyfish Stings

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_158584.html Heat Beats Cold for Treating Jellyfish Stings Evidence favors hot water or hot packs to ease pain ... 29, 2016 (HealthDay News) -- If you're unlucky enough to suffer a jellyfish sting, new research says that heat is better than cold for easing the pain. ...

  14. Beat the Instructor: An Introductory Forecasting Game

    Science.gov (United States)

    Snider, Brent R.; Eliasson, Janice B.

    2013-01-01

    This teaching brief describes a 30-minute game where student groups compete in-class in an introductory time-series forecasting exercise. The students are challenged to "beat the instructor" who competes using forecasting techniques that will be subsequently taught. All forecasts are graphed prior to revealing the randomly generated…

  15. Quantum beats of the rigid rotor

    OpenAIRE

    Kowalski, K.; Rembieliński, J.

    2013-01-01

    The dynamics is investigated of a free particle on a sphere (rigid rotor or rotator) that is initially in a coherent state. The instability of coherent states with respect to the free evolution leads to nontrivial time-development of averages of observables representing the position of a particle on a sphere that can be interpreted as quantum beats.

  16. Mechanical communication in cardiac cell synchronized beating

    Science.gov (United States)

    Nitsan, Ido; Drori, Stavit; Lewis, Yair E.; Cohen, Shlomi; Tzlil, Shelly

    2016-05-01

    Cell-cell communication, which enables cells to coordinate their activity and is essential for growth, development and function, is usually ascribed a chemical or electrical origin. However, cells can exert forces and respond to environment elasticity and to mechanical deformations created by their neighbours. The extent to which this mechanosensing ability facilitates intercellular communication remains unclear. Here we demonstrate mechanical communication between cells directly for the first time, providing evidence for a long-range interaction that induces long-lasting alterations in interacting cells. We show that an isolated cardiac cell can be trained to beat at a given frequency by mechanically stimulating the underlying substrate. Deformations are induced using an oscillatory mechanical probe that mimics the deformations generated by a beating neighbouring cardiac cell. Unlike electrical field stimulation, the probe-induced beating rate is maintained by the cell for an hour after the stimulation stops, implying that long-term modifications occur within the cell. These long-term alterations provide a mechanism for cells that communicate mechanically to be less variable in their electromechanical delay. Mechanical coupling between cells therefore ensures that the final outcome of action potential pacing is synchronized beating. We further show that the contractile machinery is essential for mechanical communication.

  17. Heart MRI

    Science.gov (United States)

    Magnetic resonance imaging - cardiac; Magnetic resonance imaging - heart; Nuclear magnetic resonance - cardiac; NMR - cardiac; MRI of the heart; Cardiomyopathy - MRI; Heart failure - MRI; Congenital heart disease - MRI

  18. Heart rate profile during exercise in patients with early repolarization

    Institute of Scientific and Technical Information of China (English)

    Serkan Cay; Goksel Cagirci; Ramazan Atak; Yucel Balbay; Ahmet Duran Demir; Sinan Aydogdu

    2010-01-01

    Background Both early repolarization and altered heart rate profile are associated with sudden death. In this study, we aimed to demonstrate an association between early repolarization and heart rate profile during exercise.Methods A total of 84 subjects were included in the study. Comparable 44 subjects with early repolarization and 40 subjects with normal electrocardiogram underwent exercise stress testing. Resting heart rate, maximum heart rate, heart rate increment and decrement were analyzed.Results Both groups were comparable for baseline characteristics including resting heart rate. Maximum heart rate, heart rate increment and heart rate decrment of the subjects in early repolarization group had significantly decreased maximum heart rate, heart rate increment and heart rate decrement compared to control group (all P<0.05). The lower heart rate increment (<106 beats/min) and heart rate decrement (<95 beats/min) were significantly associated with the presence of early repolarization. After adjustment for age and sex, the multiple-adjusted OR of the risk of presence of early repolarization was 2.98 (95% CI 1.21-7.34) (P=0.018) and 7.73 (95% CI 2.84-21.03) (P <0.001) for the lower heart rate increment and heart rate decrement compared to higher levels, respectively.Conclusions Subjects with early repolarization have altered heart rate profile during exercise compared to control subjects. This can be related to sudden death.

  19. Left ventricular beat to beat performance in atrial fibrillation: dependence on contractility, preload, and afterload

    OpenAIRE

    Muntinga, H; Gosselink, A; Blanksma, P; De Kam, P J; van der Wall, E; Crijns, H.

    1999-01-01

    OBJECTIVE—To assess independent determinants of beat to beat variation in left ventricular performance during atrial fibrillation.
DESIGN—Prospective study.
SETTING—University hospital.
PATIENTS—Seven patients with chronic non-valvar atrial fibrillation.
INTERVENTIONS—Invasive and non-invasive haemodynamic variables were assessed using a non-imaging computerised nuclear probe, a balloon tipped flow directed catheter, and a non-invasive fingertip blood pressure measurement system linked to a p...

  20. In time with rhythms : beat perception and sensorimotor synchronisation

    NARCIS (Netherlands)

    Schlichting, Nadine

    2015-01-01

    Music and beat perception are strongly connected to movement, a phenomenon known as sensorimotor synchronisation. Neurophysiologically, simple metronome-like beat sounds entrain neural oscillations, so that the brain oscillates with the same frequency as the beat frequency. The usefulness of being e

  1. Finger beat-to-beat blood pressure responses to successive hand elevations.

    Science.gov (United States)

    Raamat, R; Jagomägi, K; Talts, J; Mäger, I

    2009-06-01

    We investigated finger beat-to-beat blood pressure responses to a series of successive hand elevations in 14 normal volunteers. By passive elevation of the hand by 40 cm and lowering it again after a minute, calibrated hydrostatic pressure changes were induced in the finger arteries of the subjects. Three successive procedures with a 2-min interval between them were performed. Transitions between positions were completed smoothly over a 10-s period. Non-invasive beat-to-beat mean arterial pressure (MAP) in the finger arteries was measured by applying the servo-oscillometric physiograph (University of Tartu, Estonia). A good agreement between the evoked MAP changes during all the three hand elevations (-31.2, -30.4 and -30.0 mmHg, respectively) and the calculated hydrostatic pressure change (-31.0 mmHg) was obtained. The height difference of approximately 40 cm and rate of 4-5 cm/s can be recommended for the hand elevation test, greater postural changes and higher rates may diminish agreement between the measured blood pressure response and the corresponding hydrostatic pressure change. The applied hydrostatic test may be helpful for assessing the accuracy of beat-to-beat finger blood pressure measurement. PMID:19027338

  2. Intra-operative trans-esophageal echocardiography in congenital heart disease

    OpenAIRE

    Garg Rajnish; Murthy Keshava; Rao Shekhar; Muralidhar Kanchi

    2009-01-01

    Intra-operative trans-esophageal echocardiography (TEE) is an important monitoring and diagnostic tool used during surgery for repair of congenital heart disease. In several studies,TEE has been shown to provide additional intra-cardiac anatomic information. Its ability to be used intra- operatively before and after cardiac repair makes it a unique tool. Before TEE was available for intra-operative use, significant residual abnormalities were frequently not detected. The result was ofte...

  3. Adult murine skeletal muscle contains cells that can differentiate into beating cardiomyocytes in vitro.

    Directory of Open Access Journals (Sweden)

    Steve O Winitsky

    2005-04-01

    Full Text Available It has long been held as scientific fact that soon after birth, cardiomyocytes cease dividing, thus explaining the limited restoration of cardiac function after a heart attack. Recent demonstrations of cardiac myocyte differentiation observed in vitro or after in vivo transplantation of adult stem cells from blood, fat, skeletal muscle, or heart have challenged this view. Analysis of these studies has been complicated by the large disparity in the magnitude of effects seen by different groups and obscured by the recently appreciated process of in vivo stem-cell fusion. We now show a novel population of nonsatellite cells in adult murine skeletal muscle that progress under standard primary cell-culture conditions to autonomously beating cardiomyocytes. Their differentiation into beating cardiomyocytes is characterized here by video microscopy, confocal-detected calcium transients, electron microscopy, immunofluorescent cardiac-specific markers, and single-cell patch recordings of cardiac action potentials. Within 2 d after tail-vein injection of these marked cells into a mouse model of acute infarction, the marked cells are visible in the heart. By 6 d they begin to differentiate without fusing to recipient cardiac cells. Three months later, the tagged cells are visible as striated heart muscle restricted to the region of the cardiac infarct.

  4. Radionuclide angiocardiography in the diagnosis of congenital heart disorders

    Energy Technology Data Exchange (ETDEWEB)

    Jones, R.H.; Austin, E.H.; Peter, C.A.; Sabiston, D.C. Jr.

    1981-06-01

    Radionuclide angiocardiography provides a noninvasive assessment of cardiac function and blood flow through the heart and lungs. During the past three years, this procedure has been used at the Duke University Medical Center for evaluation of 343 patients with congenital heart disorders. A review of this experience shows tat the resulting data were frequently useful in the surgical management of these patients. In patients with abnormal blood flow patterns, noninvasive imaging of blood flow was useful before and after operative correction. Radionuclide measurements of left-to-right intracardiac shunts were sufficiently accurate for use in the initial evaluation of patients with murmurs and to document the absence of shunt after operative closure of intracardiac septal defects. Moreover, measurements of right-to-left cardiac shunts were of benefit in the management of children with cyanotic heart disease. Measurements of left ventricular function obtained during rest and exercise were most useful in patients with origin of the left coronary artery from the pulmonary artery and in patients with congenital valvular insufficiency. This experience demonstrates that radionuclide angiocardiography provides important measurements of central hemodynamics and cardiac function which are useful in the management of patients with congenital heart disorders.

  5. 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.

  6. Beat that Word: How Listeners Integrate Beat Gesture and Focus in Multimodal Speech Discourse.

    Science.gov (United States)

    Dimitrova, Diana; Chu, Mingyuan; Wang, Lin; Özyürek, Asli; Hagoort, Peter

    2016-09-01

    Communication is facilitated when listeners allocate their attention to important information (focus) in the message, a process called "information structure." Linguistic cues like the preceding context and pitch accent help listeners to identify focused information. In multimodal communication, relevant information can be emphasized by nonverbal cues like beat gestures, which represent rhythmic nonmeaningful hand movements. Recent studies have found that linguistic and nonverbal attention cues are integrated independently in single sentences. However, it is possible that these two cues interact when information is embedded in context, because context allows listeners to predict what information is important. In an ERP study, we tested this hypothesis and asked listeners to view videos capturing a dialogue. In the critical sentence, focused and nonfocused words were accompanied by beat gestures, grooming hand movements, or no gestures. ERP results showed that focused words are processed more attentively than nonfocused words as reflected in an N1 and P300 component. Hand movements also captured attention and elicited a P300 component. Importantly, beat gesture and focus interacted in a late time window of 600-900 msec relative to target word onset, giving rise to a late positivity when nonfocused words were accompanied by beat gestures. Our results show that listeners integrate beat gesture with the focus of the message and that integration costs arise when beat gesture falls on nonfocused information. This suggests that beat gestures fulfill a unique focusing function in multimodal discourse processing and that they have to be integrated with the information structure of the message. PMID:27027421

  7. 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…

  8. Estimation of post mortem interval by tomographic images of intra-cardiac hypostasis.

    Science.gov (United States)

    Zerbini, Talita; da Silva, Luiz Fernando Ferraz; Lobato Baptista, Pedro Artur; Ikari, Eduardo Seigo; Rodrigues de Araujo, Marina; de André, Carmen Diva Saldiva; da Motta Singer, Julio; da Rocha, Francisco Marcelo Monteiro; Junior, Edson Amaro; Pasqualucci, Carlos Augusto Gonçalves; Saldiva, Paulo Hilario Nascimento

    2016-02-01

    The determination of the post mortem interval (PMI) is important in many instances, especially in criminal investigations. So, we consider post mortem tomographic evaluation of intra-cardiac hypostasis as an additional method for such purpose. Tomographic images of the thoraces of the corpses of 23 patients who died in a hospital were obtained sequentially at one hour intervals to allow the analysis of changes in density due to hypostasis over time. The right and left atria, which appear in the mediastinal window, were selected for measurements of the average organ density. An exponential model was used to relate the difference between the attenuation coefficients of the anterior segment of the right atrium and the posterior segment of the left atrium to the PMI. In spite of the large variability of the data from this observational study, PMI estimates during the first 12 h after death can be estimated with a margin of error smaller than two hours. The results suggest that the difference between the attenuation coefficients stabilizes around 12 h post mortem and may be used as an additional method to estimate the PMI. PMID:26802976

  9. Surface electrocardiogram reconstruction from intracardiac electrograms using a dynamic time delay artificial neural network

    Science.gov (United States)

    Porée, Fabienne; Kachenoura, Amar; Carrault, Guy; Dal Molin, Renzo; Mabo, Philippe; Hernandez, Alfredo I.

    2013-01-01

    The study proposes a method to facilitate the remote follow-up of patients suffering from cardiac pathologies and treated with an implantable device, by synthesizing a 12-lead surface ECG from the intracardiac electrograms (EGM) recorded by the device. Two methods (direct and indirect), based on dynamic Time Delay artificial Neural Networks (TDNN) are proposed and compared with classical linear approaches. The direct method aims to estimate 12 different transfer functions between the EGM and each surface ECG signal. The indirect method is based on a preliminary orthogonalization phase of the available EGM and ECG signals, and the application of the TDNN between these orthogonalized signals, using only three transfer functions. These methods are evaluated on a dataset issued from 15 patients. Correlation coefficients calculated between the synthesized and the real ECG show that the proposed TDNN methods represent an efficient way to synthesize 12-lead ECG, from two or four EGM and perform better than the linear ones. We also evaluate the results as a function of the EGM configuration. Results are also supported by the comparison of extracted features and a qualitative analysis performed by a cardiologist. PMID:23086502

  10. Newborn infants detect the beat in music.

    Science.gov (United States)

    Winkler, István; Háden, Gábor P; Ladinig, Olivia; Sziller, István; Honing, Henkjan

    2009-02-17

    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 origin of music. Theorists are divided on the issue whether this ability is innate or learned. We show that newborn infants develop expectation for the onset of rhythmic cycles (the downbeat), even when it is not marked by stress or other distinguishing spectral features. Omitting the downbeat elicits brain activity associated with violating sensory expectations. Thus, our results strongly support the view that beat perception is innate.

  11. Modeling of Nonlinear Beat Signals of TAE's

    Science.gov (United States)

    Zhang, Bo; Berk, Herbert; Breizman, Boris; Zheng, Linjin

    2012-03-01

    Experiments on Alcator C-Mod reveal Toroidal Alfven Eigenmodes (TAE) together with signals at various beat frequencies, including those at twice the mode frequency. The beat frequencies are sidebands driven by quadratic nonlinear terms in the MHD equations. These nonlinear sidebands have not yet been quantified by any existing codes. We extend the AEGIS code to capture nonlinear effects by treating the nonlinear terms as a driving source in the linear MHD solver. Our goal is to compute the spatial structure of the sidebands for realistic geometry and q-profile, which can be directly compared with experiment in order to interpret the phase contrast imaging diagnostic measurements and to enable the quantitative determination of the Alfven wave amplitude in the plasma core

  12. Heart Disease

    Science.gov (United States)

    ... Got Homework? Here's Help White House Lunch Recipes Heart Disease KidsHealth > For Kids > Heart Disease Print A A ... chest pain, heart attacks, and strokes . What Is Heart Disease? The heart is the center of the cardiovascular ...

  13. 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 ...

  14. Beat-to-beat left ventricular performance in atrial fibrillation: radionuclide assessment with the computerized nuclear probe

    International Nuclear Information System (INIS)

    There is wide beat-to-beat variability in cycle length and left ventricular performance in patients with atrial fibrillation. In this study, left ventricular ejection fraction and relative left ventricular volumes were evaluated on a beat-to-beat basis with the computerized nuclear probe, an instrument with sufficiently high sensitivity to allow continuous evaluation of the radionuclide time-activity curve. Of 18 patients with atrial fibrillation, 5 had mitral stenosis, 6 had mitral regurgitation, and 7 had coronary artery disease. Fifty consecutive beats were analyzed in each patient. The mean left ventricular ejection fraction ranged from 17 to 51%. There was substantial beat-to-beat variation in cycle length and left ventricular ejection fraction in all patients, including those with marked left ventricular dysfunction. In 14 patients who also underwent multiple gated cardiac blood pool imaging, there was an excellent correlation between mean ejection fraction derived from the nuclear probe and gated ejection fraction obtained by gamma camera imaging (r . 0.90). Based on beat-to-beat analysis, left ventricular function was dependent on relative end-diastolic volume and multiple preceding cycle lengths, but not preceding end-systolic volumes. This study demonstrates that a single value for left ventricular ejection fraction does not adequately characterize left ventricular function in patients with atrial fibrillation. Furthermore, both the mean beat-to-beat and the gated ejection fraction may underestimate left ventricular performance at rest in such patients

  15. ZebraBeat: a flexible platform for the analysis of the cardiac rate in zebrafish embryos

    Science.gov (United States)

    de Luca, Elisa; Zaccaria, Gian Maria; Hadhoud, Marwa; Rizzo, Giovanna; Ponzini, Raffaele; Morbiducci, Umberto; Santoro, Massimo Mattia

    2014-05-01

    Heartbeat measurement is important in assesssing cardiac function because variations in heart rhythm can be the cause as well as an effect of hidden pathological heart conditions. Zebrafish (Danio rerio) has emerged as one of the most useful model organisms for cardiac research. Indeed, the zebrafish heart is easily accessible for optical analyses without conducting invasive procedures and shows anatomical similarity to the human heart. In this study, we present a non-invasive, simple, cost-effective process to quantify the heartbeat in embryonic zebrafish. To achieve reproducibility, high throughput and flexibility (i.e., adaptability to any existing confocal microscope system and with a user-friendly interface that can be easily used by researchers), we implemented this method within a software program. We show here that this platform, called ZebraBeat, can successfully detect heart rate variations in embryonic zebrafish at various developmental stages, and it can record cardiac rate fluctuations induced by factors such as temperature and genetic- and chemical-induced alterations. Applications of this methodology may include the screening of chemical libraries affecting heart rhythm and the identification of heart rhythm variations in mutants from large-scale forward genetic screens.

  16. 机器人非体外循环冠状动脉旁路移植与支架置入杂交手术%Myocardial "hybrid" revascularization-totally endoscopic coronary bypass grsfting on beating heart and stent placement-in-termediate results of an alternative approach to multivessel coronary artery disease

    Institute of Scientific and Technical Information of China (English)

    高长青; 刘宏斌; 卢才义; 杨明; 王刚; 王加利; 李丽霞; 赵悦; 肖苍松; 吴扬; 周琪

    2008-01-01

    目的 总结"达芬奇S"(da Vinic S)机器人下非体外循环冠状动脉旁路移植与支架置入杂交手术技术特点和优势.方法 2007年1~8月使用da Vinic S机器人系统,完成非体外循环冠状动脉旁路移植共42例,其中10例因双支冠脉病变,在机器人旁路手术后行支架置入术.病人平均年龄为(62.3±12.1)岁,其中男8例,女2例.病人冠状动脉造影均显示严重的前降支病变,并合并有回旋支或右冠状动脉的局限性狭窄.所有病人肺功能良好,无胸膜炎和左侧胸腔手术史.机器人手术过程中无需正中开胸,仅左侧胸壁打直径为1 cm的器械臂孔3个,术者于da Vinic S系统的操作台前、三维成像系统下遥控机器人全程游离乳内动脉;其中4例直接行全机器人非体外行循环下冠状动脉旁路移植术(TECAB),另6例于左侧胸壁第4肋间作6~8cm的小切口,在心脏跳动下行乳内动脉和前降支的吻合(SVST).术后1周左右经股动脉常规行回旋支或右冠状动脉支架置入术.置入术中行乳内动脉造影评价再血管化效果.结果 病人术后恢复顺利,并成功接受支架置入术,乳内动脉旁路血管通畅,无并发症发生.结论 应用机器人微创冠脉旁路手术和支架置入杂交手术治疗冠心病,可最大限度的减小手术创伤并实现完全再血管化.%Objective To summarize the first group of off-pump robotic bypass surgeries and stent placement in distinct hybrid session in China. Methods Forty-two patients underwent selective robotic coronary bypass grafting on the beating heart from April 2007 to August 2008. Ten cases with right coronary artery or circumflexc circumflex coronary stenosis received stent placement after roboti surgery in a hybrid manner. The average age of patients was (62.3±12.1) yeas old. Two cases were female and 8 male. All the patients had histocy of anagina. The coronary arteriography showed significant stenosis in the left anterior descending

  17. 胎儿心内强光点与染色体异常的关系%Relationship between intracardiac echogenic focus in fetus and chromosomal abnormality

    Institute of Scientific and Technical Information of China (English)

    林洪亮; 陈必良

    2012-01-01

    The occurrence of the intracardiac echogenic focus ( ICEF ) within the ventricles of the fetal heart is found and well known in mid-1980s. The histopathological manifestation of this sonographic sign is a microcalcification in papillary muscle. Such appearance is initially thought to be entirely benign. In 1992, Roberts and Genest reported microcalcifications in ventricles in 16% of fetuses with trisomy 21, 39% of fetuses with trisomy 13 , and 2% of normal chromosome fetuses. Since then, studies on its clinical significance especially the association with fetal chromosoamal abnormality never stop. The aim of this article was to review the literatures on this topic.%胎儿心内强回声光点于上个世纪80年代被人们发现而熟悉,其病理组织表现为心室内乳突肌的微小钙化灶.最初仅将其看做一种纯粹的良性发现.1992年Roberts和Genest发现16%的21三体胎儿、39%的13三体胎儿以及2%的染色体正常胎儿心室内有这种微小钙化灶.之后学者们开始对胎儿心内强回声光点的临床意义特别是与染色体异常的关系进行了大量的研究,现对其进行综述.

  18. 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.

  19. 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…

  20. Unobtrusive heart rate monitor based on a fiber specklegram sensor and a single-board computer

    Science.gov (United States)

    Benevides, Alessandro B.; Frizera, Anselmo; Cotrina, Anibal; Ribeiro, Moisés. R. N.; Segatto, Marcelo E. V.; Pontes, Maria José

    2015-09-01

    This paper proposes a portable and unobtrusive heart rate monitor based on fiber specklegram sensors. The proposed module uses the Raspberry Pi module to perform the image acquisition and the fiber specklegram sensor, which is based on multimode plastic optical fibers. The heart rate is obtained by welch power spectral density estimate and the heart beats are identified by means of a threshold analysis.

  1. Using Complexity Metrics With R-R Intervals and BPM Heart Rate Measures

    DEFF Research Database (Denmark)

    Wallot, Sebastian; Fusaroli, Riccardo; Tylén, Kristian;

    2013-01-01

    on variability of the data, different choices regarding the kind of measures can have a substantial impact on the results. In this article we compare linear and non-linear statistics on two prominent types of heart beat data, beat-to-beat intervals (R-R interval) and beats-per-minute (BPM). As a proof...... dynamics, but their power to do so critically depends on the type data that is employed: While R-R intervals are very susceptible to nonlinear analyses, the success of nonlinear methods for BPM data critically depends on their construction. Generally, ‘oversampled’ BPM time-series can be recommended...

  2. 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. PMID:26354957

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

    Directory of Open Access Journals (Sweden)

    Christine H. Attenhofer Jost

    2013-01-01

    Full Text Available 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.

  4. Heart Rate Variability Frekuensi Domain Untuk Deteksi Stres Mental Dan Influenza Menggunakan SVM Classifier

    OpenAIRE

    Novani, Nefy Puteri; Prihatmanto, Ary Setijadi

    2016-01-01

    Heart Rate Variability (HRV) merupakan variasi dari beat-to-beat denyut jantung yang memberikan gambaran gejala fisiologis dari denyut jantung (heart rate) dengan variasinya dalam interval waktu. Analisis HRV memberikan suatu informasi tentang modulasi otonom jantung dan menjadi alat yang berguna untuk memahami sistem saraf otonom (ANS) yang mengatur proses-proses tertentu di dalam tubuh dengan dua komponen utama yaitu sistem saraf simpatetik dan parasimpatetik. Analisis HRV mencakup anali...

  5. 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...... minute or more. METHODS: We conducted a randomized, double-blind, placebo-controlled trial of ivabradine, added to standard background therapy, in 19,102 patients who had both stable coronary artery disease without clinical heart failure and a heart rate of 70 beats per minute or more (including 12...... without activity-limiting angina (P=0.02 for interaction). The incidence of bradycardia was higher with ivabradine than with placebo (18.0% vs. 2.3%, Pcoronary artery disease without clinical heart failure, the addition of ivabradine to standard...

  6. The Harvard Beat Assessment Test (H-BAT): a battery for assessing beat perception and production and their dissociation.

    Science.gov (United States)

    Fujii, Shinya; Schlaug, Gottfried

    2013-01-01

    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.

  7. The Harvard Beat Assessment Test (H-BAT): a battery for assessing beat perception and production and their dissociation

    Science.gov (United States)

    Fujii, Shinya; Schlaug, Gottfried

    2013-01-01

    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. PMID:24324421

  8. 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

  9. Attosecond Quantum-Beat Spectroscopy in Helium

    CERN Document Server

    Shivaram, Niranjan; Timmers, Henry; Sandhu, Arvinder

    2015-01-01

    The evolution of electron wavepackets determines the course of many physical and chemical phenomena and attosecond spectroscopy aims to measure and control such dynamics in real-time. Here, we investigate radial electron wavepacket motion in Helium by using an XUV attosecond pulse train to prepare a coherent superposition of excited states and a delayed femtosecond IR pulse to ionize them. Quantum beat signals observed in the high resolution photoelectron spectrogram allow us to follow the field-free evolution of the bound electron wavepacket and determine the time-dependent ionization dynamics of the low-lying 2p state.

  10. Advances in Understanding of Mechanism and Treatment of Intracardiac Thrombosis%心腔内血栓形成机制与治疗研究进展

    Institute of Scientific and Technical Information of China (English)

    傅德建

    2011-01-01

    The pathogenesis of intracardiac thrombosis is complex and is still not fully understood. The current known pathological mechanisms include damage to endocardial endothelial system, blood state changes, and increased blood coagulation, among others. Throm-bolytic therapy is emerging as a treatment for intracardiac thrombosis. This article reviews current advances in the understanding of the mechanism and treatment of intracardiac thrombosis.%心腔内血栓形成因素复杂,发病机理仍在研究.目前的病理机制:心内膜内皮系统损坏、血液状态的改变、血液凝固性增高、炎症反应等.治疗上随基因药物出现,抗栓溶栓的治疗更具特异性,同时更加安全.

  11. 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.

  12. Heart Transplant

    Science.gov (United States)

    ... 2015 A heart transplant gives a patient with congenital heart disease the opportunity to have a normal heart with ... pulmonary artery and left atrium. In patients with congenital heart disease, the surgeon may simultaneous transplant the lungs and ...

  13. Heart Block

    Science.gov (United States)

    ... the signal causes the heart to contract and pump blood. Heart block occurs if the electrical signal is ... degree heart block limits the heart's ability to pump blood to the rest of the body. This type ...

  14. Beat-rate dependent mitral flow patterns for in vitro hemodynamic applications.

    Science.gov (United States)

    Vismara, Riccardo; Fiore, Gianfranco B

    2010-12-01

    The conservative surgery approach for restoring the functionality of heart valves has predominated during the last two decades, particularly for the mitral valve. In vitro pulsatile testing is a key methodology for the investigation of heart valve hemodynamics, and particularly for the ideation, validation and optimization of novel techniques in heart valve surgery. Traditionally, however, pulsatile mock loops have been developed for the study of aortic valve substitutes, and scarce attention has been paid in replicating the mitral flow patterns with due hemodynamic fidelity. In this work we provide detailed analytical expressions to produce beat-rate dependent, physiologic-like mitral flow patterns for in vitro applications. The approach we propose is based on a biomechanical analysis of the factors which govern hemodynamic changes in the mitral flow pattern, namely in terms of E and A wave contours and E/A peaks ratio, when switching from rest to mild exercise conditions. The patterns from the model we obtained were in good agreement with clinical literature data in terms of i) gradual superimposition of the E and A wave, which yielded a single peak at 96 bpm; ii) decrease in the E/A ratio with increasing heart rate; iii) amount of flow delivered by each of the two waves. The proposed method provides a physiologically representative, beat-rate dependent analytical expression of the mitral flow pattern, which can be used in in vitro hydrodynamic investigations to accurately replicate the changes that the flow waves experience when the heart rate shifts from rest to mild exercise conditions.

  15. Cardiac fluid dynamics anticipates heart adaptation.

    Science.gov (United States)

    Pedrizzetti, Gianni; Martiniello, Alfonso R; Bianchi, Valter; D'Onofrio, Antonio; Caso, Pio; Tonti, Giovanni

    2015-01-21

    Hemodynamic forces represent an epigenetic factor during heart development and are supposed to influence the pathology of the grown heart. Cardiac blood motion is characterized by a vortical dynamics, and it is common belief that the cardiac vortex has a role in disease progressions or regression. Here we provide a preliminary demonstration about the relevance of maladaptive intra-cardiac vortex dynamics in the geometrical adaptation of the dysfunctional heart. We employed an in vivo model of patients who present a stable normal heart function in virtue of the cardiac resynchronization therapy (CRT, bi-ventricular pace-maker) and who are expected to develop left ventricle remodeling if pace-maker was switched off. Intra-ventricular fluid dynamics is analyzed by echocardiography (Echo-PIV). Under normal conditions, the flow presents a longitudinal alignment of the intraventricular hemodynamic forces. When pacing is temporarily switched off, flow forces develop a misalignment hammering onto lateral walls, despite no other electro-mechanical change is noticed. Hemodynamic forces result to be the first event that evokes a physiological activity anticipating cardiac changes and could help in the prediction of longer term heart adaptations.

  16. The chemical composition of Galactic beat Cepheids

    Science.gov (United States)

    Kovtyukh, V.; Lemasle, B.; Chekhonadskikh, F.; Bono, G.; Matsunaga, N.; Yushchenko, A.; Anderson, R. I.; Belik, S.; da Silva, R.; Inno, L.

    2016-08-01

    We determine the metallicity and detailed chemical abundances (α, iron-peak and neutron-capture elements) for the almost complete (18/24) sample of Galactic double mode Cepheids (also called beat Cepheids). Double mode Cepheids are Cepheids that pulsate in two modes simultaneously. We calibrate a new relation between their metallicity and their period ratio P1/P0. This linear relation allows to determine the metallicity of bimodal Cepheids with an accuracy of 0.03 dex in the range of [Fe/H] from +0.2 to -0.5 dex. By extrapolating the relation to Magellanic Clouds beat Cepheids, we provide their metallicity distribution function. Moreover, by using this relation, we also provide the first metallicity estimate for two double-mode F/1O Cepheids located in and beyond the Galactic bulge. Finally, we report the discovery of a super-Lithium rich double mode Cepheid V371 Per which has a Lithium abundance of logA(Li) = 3.54 ± 0.09 dex. Along with V1033 Cyg (which is an ordinary classical Cepheid), it is the second known Cepheid of such type in the Galaxy.

  17. 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.

  18. Ceftiofur pharmacokinetics in Nile tilapia Oreochromis niloticus after intracardiac and intramuscular administrations.

    Science.gov (United States)

    Khalil, Waleed F; Shaheen, Hazem M; Abdou, Rania H

    2016-08-31

    Ceftiofur is a broad-spectrum third generation cephalosporin, which acts by inhibiting bacterial cell wall synthesis. It is active against Gram-positive and Gram-negative bacteria such as Aeromonas hydrophila and β-lactamase-producing strains, which are common pathogens in freshwater fish. Ceftiofur pharmacokinetics in Nile tilapia Oreochromis niloticus were studied following single intracardiac (i.c.) or intramuscular (i.m.) administration of ceftiofur sodium (NAXCEL®) in a dose of 5 mg ceftiofur kg-1 body weight. After i.c. injection, ceftiofur plasma concentrations decreased biexponentially, suggesting a 2-compartmental open model. Distribution and elimination half-lives (t0.5(α) and t0.5(β)) were 0.61 ± 0.22 and 0.14 ± 0.03 h mean ±SD, respectively. Elimination constant (Kel) and total body clearances (Cltot) were 3.22 ± 0.48 h-1 and 1.64 ± 0.47 l h-1 kg-1, respectively. Volume of distribution (Vss) and areas under curves (AUC) were 0.12 ± 0.03 l kg-1 and 24.18 ± 8.81 µg ml-1 h, respectively. Following i.m. injection of ceftiofur, plasma concentrations were best described by a 1-compartment open model with a first order absorption; bioavailability was quite high (96.85 ± 23.74%). Plasma maximum concentration (Cmax) was 12.32 ± 6.53 µg ml-1; achieved at time of maximum concentration (Tmax) of 0.74 ± 0.04 h. Absorption and elimination half-lives (t0.5ab and t0.5β) were 0.49 ± 0.06 and 0.53 ± 0.03 h, respectively. In conclusion, i.m. injection of ceftiofur sodium produced extremely high bioavailability with high plasma concentrations that persisted up to 6 h post injection, which may make ceftiofur a useful alternative antibiotic for treatment of brood stock or important ornamental fishes. PMID:27596857

  19. Heart Rate Extraction from Vowel Speech Signals

    Institute of Scientific and Technical Information of China (English)

    Abdelwadood Mesleh; Dmitriy Skopin; Sergey Baglikov; Anas Quteishat

    2012-01-01

    This paper presents a novel non-contact heart rate extraction method from vowel speech signals.The proposed method is based on modeling the relationship between speech production of vowel speech signals and heart activities for humans where it is observed that the moment of heart beat causes a short increment (evolution) of vowel speech formants.The short-time Fourier transform (STFT) is used to detect the formant maximum peaks so as to accurately estimate the heart rate.Compared with traditional contact pulse oximeter,the average accuracy of the proposed non-contact heart rate extraction method exceeds 95%.The proposed non-contact heart rate extraction method is expected to play an important role in modern medical applications.

  20. Increased Short-Term Beat-To-Beat Variability of QT Interval in Patients with Acromegaly.

    Directory of Open Access Journals (Sweden)

    Andrea Orosz

    Full Text Available Cardiovascular diseases, including ventricular arrhythmias are responsible for increased mortality in patients with acromegaly. Acromegaly may cause repolarization abnormalities such as QT prolongation and impairment of repolarization reserve enhancing liability to arrhythmia. The aim of this study was to determine the short-term beat-to-beat QT variability in patients with acromegaly. Thirty acromegalic patients (23 women and 7 men, mean age±SD: 55.7±10.4 years were compared with age- and sex-matched volunteers (mean age 51.3±7.6 years. Cardiac repolarization parameters including frequency corrected QT interval, PQ and QRS intervals, duration of terminal part of T waves (Tpeak-Tend and short-term variability of QT interval were evaluated. All acromegalic patients and controls underwent transthoracic echocardiographic examination. Autonomic function was assessed by means of five standard cardiovascular reflex tests. Comparison of the two groups revealed no significant differences in the conventional ECG parameters of repolarization (QT: 401.1±30.6 ms vs 389.3±16.5 ms, corrected QT interval: 430.1±18.6 ms vs 425.6±17.3 ms, QT dispersion: 38.2±13.2 ms vs 36.6±10.2 ms; acromegaly vs control, respectively. However, short-term beat-to-beat QT variability was significantly increased in acromegalic patients (4.23±1.03 ms vs 3.02±0.80, P<0.0001. There were significant differences between the two groups in the echocardiographic dimensions (left ventricular end diastolic diameter: 52.6±5.4 mm vs 48.0±3.9 mm, left ventricular end systolic diameter: 32.3±5.2 mm vs 29.1±4.4 mm, interventricular septum: 11.1±2.2 mm vs 8.8±0.7 mm, posterior wall of left ventricle: 10.8±1.4 mm vs 8.9±0.7 mm, P<0.05, respectively. Short-term beat-to-beat QT variability was elevated in patients with acromegaly in spite of unchanged conventional parameters of ventricular repolarization. This enhanced temporal QT variability may be an early indicator of increased

  1. Acupuncture Treatment for 98 Cases of Ventricular Premature Beat

    Institute of Scientific and Technical Information of China (English)

    Han Baojie; Wang Feng; Wang Xinzhong

    2008-01-01

    @@ Ventricular premature beat is a commonly encountered arrhythmia,which can occur in patients with and without cardiac diseases.In TCM.ventricular premature beat fall into the category of palpitation and obstruction of qi in the chest.The authors treated it with acupuncture and obtained satisfactory thera-peutic effects.A summary follows.

  2. 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.

  3. IN VIVO CHARACTERIZATION OF ATTACHMENT SAFETY BETWEEN CARDIAC PACING LEAD AND CANINE HEART MUSCLE

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In vivo experiments of screwing the electrode of canine hearts and assigning external excitation on the lead-myocardium interface was carried out to evaluate the lead/myocardium adherence safety. The electrode is specially designed to host a measurement unit of strain gauges.We obtained the lead/heart interactions data from 12 dogs under natural heart beating and beating with external excitations. The data recorded from the acute phase and the chronic phase of pulling out pacing leads were compared with each other. The electrode/heart interaction is caused by the heart beat and influenced by the lung breath. This process induced tolerable damage to the lead or myocardium. The interaction decreases as the frequency of external excitations increases. The lead is more likely to be detached from myocardium under higher excitation frequency. At the same implanting sites, safer pacing lead/myocardium attachment can be realized in the chronic tests than in the acute tests.

  4. 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. PMID:27378982

  5. 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. PMID:27378982

  6. Nonlinear amplitude dynamics in flagellar beating

    CERN Document Server

    Oriola, David; Casademunt, Jaume

    2016-01-01

    The physical basis of flagellar and ciliary beating is a major problem in biology which is still far from completely understood. The fundamental cytoskeleton structure of cilia and flagella is the axoneme, a cylindrical array of microtubule doublets connected by passive crosslinkers and dynein motor proteins. The complex interplay of these elements leads to the generation of self-organized bending waves. Although many mathematical models have been proposed to understand this process, few attempts have been made to assess the role of dyneins on the nonlinear nature of the axoneme. Here, we investigate the nonlinear dynamics of flagella by considering an axonemal sliding control mechanism for dynein activity. This approach unveils the nonlinear selection of the oscillation amplitudes, which are typically either missed or prescribed in mathematical models. The explicit set of nonlinear equations are derived and solved numerically. Our analysis reveals the spatiotemporal dynamics of dynein populations and flagell...

  7. Increased Short-Term Beat-To-Beat Variability of QT Interval in Patients with Acromegaly.

    Science.gov (United States)

    Orosz, Andrea; Csajbók, Éva; Czékus, Csilla; Gavallér, Henriette; Magony, Sándor; Valkusz, Zsuzsanna; Várkonyi, Tamás T; Nemes, Attila; Baczkó, István; Forster, Tamás; Wittmann, Tibor; Papp, Julius Gy; Varró, András; Lengyel, Csaba

    2015-01-01

    Cardiovascular diseases, including ventricular arrhythmias are responsible for increased mortality in patients with acromegaly. Acromegaly may cause repolarization abnormalities such as QT prolongation and impairment of repolarization reserve enhancing liability to arrhythmia. The aim of this study was to determine the short-term beat-to-beat QT variability in patients with acromegaly. Thirty acromegalic patients (23 women and 7 men, mean age±SD: 55.7±10.4 years) were compared with age- and sex-matched volunteers (mean age 51.3±7.6 years). Cardiac repolarization parameters including frequency corrected QT interval, PQ and QRS intervals, duration of terminal part of T waves (Tpeak-Tend) and short-term variability of QT interval were evaluated. All acromegalic patients and controls underwent transthoracic echocardiographic examination. Autonomic function was assessed by means of five standard cardiovascular reflex tests. Comparison of the two groups revealed no significant differences in the conventional ECG parameters of repolarization (QT: 401.1±30.6 ms vs 389.3±16.5 ms, corrected QT interval: 430.1±18.6 ms vs 425.6±17.3 ms, QT dispersion: 38.2±13.2 ms vs 36.6±10.2 ms; acromegaly vs control, respectively). However, short-term beat-to-beat QT variability was significantly increased in acromegalic patients (4.23±1.03 ms vs 3.02±0.80, Pacromegaly in spite of unchanged conventional parameters of ventricular repolarization. This enhanced temporal QT variability may be an early indicator of increased liability to arrhythmia.

  8. Gimme the beat: assessment of low frequency beat noise for drilling rig

    Energy Technology Data Exchange (ETDEWEB)

    Bilawchuk, Steven; Froment, Patrick [aci Acoustical Consultants Inc. (Canada)], email: stevenb@aciacoustical.com, email: patrickf@aciacoustical.com

    2011-07-01

    The concern of an Alberta resident over the noise level from a drilling rig led to a low frequency noise impact assessment being done by an acoustic consulting firm. This paper describes the investigation that was conducted to determine the low frequency noise source, evaluate its sound emission levels and spectra, and propose mitigation options. Noise measurements were made over several days, with a sound level meter and additionally, a weather monitoring station was also used. Analysis showed low frequency tonal noise at the residential location, resulting in an overall sound level exceeding the permissible sound level imposed by the Alberta noise regulating bodies. Moreover, a beat phenomenon was observed, and after detailed investigation of possible sources, it was established that shale shakers were responsible for the low frequency noise and the beat phenomenon, a fact verified by beat theory. Due to the temporary nature of the drilling rig's operation, no thorough mitigation options could be proposed but a simple stop gap solution for the shale shakers allowed the reduction of low frequency tonal noise.

  9. 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.

  10. Immunohistochemical Distribution of Serum Proteins in Living Mouse Heart with In Vivo Cryotechnique

    OpenAIRE

    Shi, Liye; Terada, Nobuo; Saitoh, Yurika; Saitoh, Sei; Ohno, Shinichi

    2011-01-01

    In vivo cryotechnique (IVCT), which immediately cryofixes target organs in situ, was used to clarify the morphological features of beating heart tissue of living mice. IVCT was performed for diastolic heart tissue under the condition of monitoring with electrocardiogram (ECG). Other mouse hearts were prepared with conventional perfusion-fixation (PF-DH) or immersion-fixation followed by dehydration (IM-DH), and quick-freezing of resected heart tissues (FQF). Immunolocalizations of albumin, im...

  11. Heart Rate Variability Classification and Feature Extraction Using Support Vector Machine and PCA: An Overview

    OpenAIRE

    Rahul Pitale; Kapil Tajane

    2014-01-01

    In today’s era Heart Rate Variability becomes an important characteristic to determine the condition of heart. That’s why the calculation of HRV and classification to generate rules is necessary. Human Heart Generates the electrical signal. ECG is used to detect the heart beat. ECG signal contains lots of noise. To classify the signals first to decompose the signals using wavelet transform. Many Mother wavelet are used to denoise the signals. Support Vector Machine is used to ...

  12. Relation of Elevated Heart Rate in Patients With Heart Failure With Reduced Ejection Fraction to One-Year Outcomes and Costs.

    Science.gov (United States)

    DeVore, Adam D; Schulte, Phillip J; Mentz, Robert J; Hardy, N Chantelle; Kelly, Jacob P; Velazquez, Eric J; Maya, Juan F; Kielhorn, Adrian; Patel, Harshali K; Reed, Shelby D; Hernandez, Adrian F

    2016-03-15

    There are limited data describing outcomes associated with an elevated heart rate in patients with heart failure with reduced ejection fraction (HFrEF) in routine clinical practice. We identified patients with HFrEF at Duke University Hospital undergoing echocardiograms and heart rate assessments without paced rhythms or atrial fibrillation. Outcomes (all-cause mortality or hospitalization and medical costs per day alive) were assessed using electronic medical records, hospital cost accounting data, and national death records. Patients were stratified by heart rate (costs and proportional hazard models for mortality/hospitalization. Of 722 eligible patients, 582 patients (81%) were treated with β blockers. The median heart rate was 81 beats/min (25th and 75th percentiles 69 to 96) and 527 patients (73%) had a heart rate ≥70 beats/min. After multivariate adjustment, a heart rate ≥70 beats/min was associated with increased 1-year all-cause mortality or hospitalization, hazard ratio 1.37 (95% CI 1.07 to 1.75) and increased medical costs per day alive, cost ratio 2.03 (95% CI 1.53 to 2.69). In conclusion, at a large tertiary care center, despite broad use of β blockers, a heart rate ≥70 beats/min was observed in 73% of patients with HFrEF and associated with worse 1-year outcomes and increased direct medical costs per day alive. PMID:26805662

  13. Quantification of fetal heart rate regularity using symbolic dynamics

    Science.gov (United States)

    van Leeuwen, P.; Cysarz, D.; Lange, S.; Geue, D.; Groenemeyer, D.

    2007-03-01

    Fetal heart rate complexity was examined on the basis of RR interval time series obtained in the second and third trimester of pregnancy. In each fetal RR interval time series, short term beat-to-beat heart rate changes were coded in 8bit binary sequences. Redundancies of the 28 different binary patterns were reduced by two different procedures. The complexity of these sequences was quantified using the approximate entropy (ApEn), resulting in discrete ApEn values which were used for classifying the sequences into 17 pattern sets. Also, the sequences were grouped into 20 pattern classes with respect to identity after rotation or inversion of the binary value. There was a specific, nonuniform distribution of the sequences in the pattern sets and this differed from the distribution found in surrogate data. In the course of gestation, the number of sequences increased in seven pattern sets, decreased in four and remained unchanged in six. Sequences that occurred less often over time, both regular and irregular, were characterized by patterns reflecting frequent beat-to-beat reversals in heart rate. They were also predominant in the surrogate data, suggesting that these patterns are associated with stochastic heart beat trains. Sequences that occurred more frequently over time were relatively rare in the surrogate data. Some of these sequences had a high degree of regularity and corresponded to prolonged heart rate accelerations or decelerations which may be associated with directed fetal activity or movement or baroreflex activity. Application of the pattern classes revealed that those sequences with a high degree of irregularity correspond to heart rate patterns resulting from complex physiological activity such as fetal breathing movements. The results suggest that the development of the autonomic nervous system and the emergence of fetal behavioral states lead to increases in not only irregular but also regular heart rate patterns. Using symbolic dynamics to

  14. Frequent ventricular premature beats increase blood pressure variability in rats

    Institute of Scientific and Technical Information of China (English)

    Chao-yu MIAO; Li-ping XU; Jian-guo LIU; He-hui XIE; Wen-jun YUAN; Ding-feng SU

    2004-01-01

    AIM: The present study was designed to test a hypothesis that nonfatal ventricular arrhythmia such as ventricular premature beats (VPB) is a contributing factor in the elevation of blood pressure variability (BPV). METHODS:Blood pressure (BP) and electrocardiogram were continuously recorded. The relation between VPB and BPV was observed under conscious state in chronic myocardial infarction (MI) rats one month after ligation of the left.coronary artery, and further verified under anesthetized state in rat model of ventricular arrhythmia produced by acute intravenous infusion of aconitine. RESULTS: MI rats exhibited a big difference in the count and pattern of VPB, and were divided into no VPB, occasional VPB, and frequent VPB groups. Among the three groups, there were no differences in BP, heart period (HP), and MI size. However, BPV was markedly higher in frequent not occasional VPB rats, and HP variability (HPV) was larger in both frequent and occasional VPB rats, when compared with no VPB rats. In the whole population of MI rats, BPV was positively correlated with VPB and HPV, not with BP, HP and MI size. Infusion of aconitine had no effect on BP, HP, BPV, and HPV during the period without VPB.Frequent VPB after several minutes of aconitine infusion induced significant increase in BPV and HPV with no change in BP and HP. BPV was also positively correlated with VPB and HPV, not with BP and HP. Hemodynamics in aconitine-evoked ventricular tachycardia was characterized as lower BP, higher BPV, and higher HPV.CONCLUSION: High BPV can be caused by frequent not occasional VPB in rats.

  15. Heart Anatomy

    Science.gov (United States)

    ... Incredible Machine Bonus poster (PDF) The Human Heart Anatomy Blood The Conduction System The Coronary Arteries The ... of the Leg Vasculature of the Torso Heart anatomy illustrations and animations for grades K-6. Heart ...

  16. The role of pygopus in the differentiation of intracardiac 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 not 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 mediates 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 with pygo heterozygotes alone. These results are consistent with the idea that pygo functions independently of canonical Wnt signaling in the differentiation of the adult interchamber cardiac valves.

  17. Conditional control of quantum beats in a cavity QED system

    CERN Document Server

    Norris, D G; Orozco, L A; 10.1088/1742-6596/274/1/012143

    2011-01-01

    We probe a ground-state superposition that produces a quantum beat in the intensity correlation of a two-mode cavity QED system. We mix drive with scattered light from an atomic beam traversing the cavity, and effectively measure the interference between the drive and the light from the atom. When a photon escapes the cavity, and upon detection, it triggers our feedback which modulates the drive at the same beat frequency but opposite phase for a given time window. This results in a partial interruption of the beat oscillation in the correlation function, that then returns to oscillate.

  18. Investigation of beat-waves generation with high efficiency

    International Nuclear Information System (INIS)

    A method for generating high power beating radio-frequency wave with high conversion efficiency is proposed. Based on Cherenkov radiation, two longitudinal resonant modes are excited simultaneously and interacted with intense electron beam synchronously. An experiment was carried out and beat-waves with an average power of about 2.3 GW, frequencies of 9.29 GHz and 10.31 GHz, and efficiency of about 40% were obtained. Through controlling the electron energy, the amplitude proportions of the two resonant modes are altered, and different beat-wave patterns are formed

  19. Beliefs about wife beating: an exploratory study with Lebanese students.

    Science.gov (United States)

    Obeid, Nadine; Chang, Doris F; Ginges, Jeremy

    2010-06-01

    In recent years, there has been a growing interest in understanding the sociocultural contexts and risk factors for domestic violence in the Arab world. This study provides an analysis of the religious, legal, and familial contexts of domestic violence in Lebanon and assesses contemporary attitudes toward women and wife beating in a sample of 206 Lebanese university students. Gender, patriarchal attitudes, religion, childhood experiences with family violence, and mother's employment status were investigated as predictors of attitudes toward wife beating. Consistent with feminist theories of wife abuse, gender and attitudes toward women's roles emerged as the strongest predictors of beliefs about wife beating. PMID:20445079

  20. Investigation of beat-waves generation with high efficiency

    Science.gov (United States)

    Song, W.; Shi, Y. C.; Deng, Y. Q.; Zhu, X. X.; Zhang, Z. Q.; Hu, X. G.

    2013-10-01

    A method for generating high power beating radio-frequency wave with high conversion efficiency is proposed. Based on Cherenkov radiation, two longitudinal resonant modes are excited simultaneously and interacted with intense electron beam synchronously. An experiment was carried out and beat-waves with an average power of about 2.3 GW, frequencies of 9.29 GHz and 10.31 GHz, and efficiency of about 40% were obtained. Through controlling the electron energy, the amplitude proportions of the two resonant modes are altered, and different beat-wave patterns are formed.

  1. Investigation of beat-waves generation with high efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Song, W.; Shi, Y. C.; Deng, Y. Q.; Zhu, X. X.; Zhang, Z. Q.; Hu, X. G. [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi' an, Shanxi 710024 (China)

    2013-10-21

    A method for generating high power beating radio-frequency wave with high conversion efficiency is proposed. Based on Cherenkov radiation, two longitudinal resonant modes are excited simultaneously and interacted with intense electron beam synchronously. An experiment was carried out and beat-waves with an average power of about 2.3 GW, frequencies of 9.29 GHz and 10.31 GHz, and efficiency of about 40% were obtained. Through controlling the electron energy, the amplitude proportions of the two resonant modes are altered, and different beat-wave patterns are formed.

  2. Certain characteristics of myocardial contractility of isovolumic dog heart at randomly variable heart rhythm.

    Science.gov (United States)

    Bershitskaya, O N; Izakov VYa; Lysenko, L T; Protsenko, J L; Trubetskoy, A V

    1985-01-01

    The relationship "heart rate - left ventricular pressure" was investigated in the isolated canine heart perfused with constant pressure at different preloads. Rhythmical stimulation was performed with constant stimulus interval duration and with stimulus intervals randomly changed near the average value (150-200 stimuli in series). Correlation and dispersion function analysis show that rhythm dispersion had a negative inotropic effect which was independent of the preload of the ventricle in the range of 120-180 beat/min, but this dependence occurred with low rats of stimulation. This method is proposed for the assessment of contractility under conditions of heart rate variations (physiological and pathological arrhythmias).

  3. 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.

  4. 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.

  5. Association between frequency of atrial and ventricular ectopic beats and biventricular pacing percentage and outcomes in patients with cardiac resynchronization therapy

    DEFF Research Database (Denmark)

    Ruwald, Martin H; Mittal, Suneet; Ruwald, Anne-Christine;

    2014-01-01

    -defibrillator device with data available on biventricular pacing percentage and pre-implantation 24-h Holter recordings were included. Using logistic regression, we estimated the influence of ectopic beats on the percentage of biventricular pacing. Reverse remodeling was measured as reductions in atrial and left...... ventricular end-systolic volumes (LVESV) at 1 year. Cox models were used to assess the influence of ectopic beats on the outcomes of heart failure (HF) or death, ventricular tachyarrhythmias (VTAs), and death. RESULTS: In the pre-implantation Holter recording, ectopic beats accounted for a mean 3.2 ± 5...... biventricular pacing (Holter monitoring of patients selected for CRT for optimal outcome. (MADIT-CRT: Multicenter Automatic Defibrillator Implantation With Cardiac Resynchronization...

  6. Worsening Hypoxemia in the Face of Increasing PEEP: A Case of Large Pulmonary Embolism in the Setting of Intracardiac Shunt.

    Science.gov (United States)

    Granati, Glen T; Teressa, Getu

    2016-01-01

    BACKGROUND Patent foramen ovale (PFO) are common, normally resulting in a left-to-right shunt or no net shunting. Pulmonary embolism (PE) can cause sustained increased pulmonary vascular resistance (PVR) and right atrial pressure. Increasing positive end-expiratory pressure (PEEP) improves oxygenation at the expense of increasing intrathoracic pressures (ITP). Airway pressure release ventilation (APRV) decreases shunt fraction, improves ventilation/perfusion (V/Q) matching, increases cardiac output, and decreases right atrial pressure by facilitating low airway pressure. CASE REPORT A 40-year-old man presented with dyspnea and hemoptysis. Oxygen saturation (SaO2) 80% on room air with A-a gradient of 633 mmHg. Post-intubation SaO2 dropped to 71% on assist control, FiO2 100%, and PEEP of 5 cmH20. Successive PEEP dropped SaO2 to 60-70% and blood pressure plummeted. APRV was initaiated with improvement in SaO2 to 95% and improvement in blood pressure. Hemiparesis developed and CT head showed infarction. CT pulmonary angiogram found a large pulmonary embolism. Transthoracic echocardiogram detected right-to left intracardiac shunt, with large PFO. CONCLUSIONS There should be suspicion for a PFO when severe hypoxemia paradoxically worsens in response to increasing airway pressures. Concomitant venous and arterial thromboemboli should prompt evaluation for intra-cardiac shunt. Patients with PFO and hypoxemia should be evaluated for causes of sustained right-to-left pressure gradient, such as PE. Management should aim to decrease PVR and optimize V/Q matching by treating the inciting incident (e.g., thrombolytics in PE) and by minimizing ITP. APRV can minimize PVR and maximize V/Q ratios and should be considered in treating patients similar to the one whose case is presented here. PMID:27377010

  7. 10.9.Coronary heart disease

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    930272 Clinical relevant factors of the my-ocardial ischemic threshold.LU Duan (鲁端),et al.1st Affil Hosp,Zhejiang Med Univ,Hangzhou,310003.Chin J cardiol 1992;20(6):357—358.The myocardial ischemic threshold (heart rateat the onset of ischemia) was assessed in 92 pa-tients with coronary heart disease.The highestmyocardial ischemic threshold (HMIT) rangedfrom 83 to 163 (122±18) beats/min usuallyhappened during activities at the daytime.Thelowest myocardial ischemic threshold (LMIT)ranged from 45 to 115 (82±17) beats/min usu-ally happened when awaken in early morning orasleep at night.The differences were statistical-

  8. "'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.

  9. Selective particle capture by asynchronously beating cilia

    Science.gov (United States)

    Ding, Yang; Kanso, Eva

    2015-12-01

    Selective particle filtration is fundamental in many engineering and biological systems. For example, many aquatic microorganisms use filter feeding to capture food particles from the surrounding fluid, using motile cilia. One of the capture strategies is to use the same cilia to generate feeding currents and to intercept particles when the particles are on the downstream side of the cilia. Here, we develop a 3D computational model of ciliary bands interacting with flow suspended particles and calculate particle trajectories for a range of particle sizes. Consistent with experimental observations, we find optimal particle sizes that maximize capture rate. The optimal size depends nonlinearly on cilia spacing and cilia coordination, synchronous vs. asynchronous. These parameters affect the cilia-generated flow field, which in turn affects particle trajectories. The low capture rate of smaller particles is due to the particles' inability to cross the flow streamlines of neighboring cilia. Meanwhile, large particles have difficulty entering the sub-ciliary region once advected downstream, also resulting in low capture rates. The optimal range of particle sizes is enhanced when cilia beat asynchronously. These findings have potentially important implications on the design and use of biomimetic cilia in processes such as particle sorting in microfluidic devices.

  10. Feathering collisions in beating reed simulation

    Science.gov (United States)

    Smyth, Tamara; Abel, Jonathan S.; Smith, Julius O.

    2003-10-01

    Pressure controlled valves are the primary sound production mechanisms for woodwind and brass musical instruments, as well as for many bioacoustic vocal systems such as the larynx and syrinx (the vocal organ in birds). During sound production, air flow sets a reed or membrane into motion creating a variable height in the valve channel and, potentially, periodically closing the channel completely. Depending on how this event is handled, an abrupt termination of air flow between open and closed states can cause undesirable discontinuities and inaccuracies in a discrete-time simulation-particularly at relatively low audio sampling rates. A solution was developed by re-examining the behavior of the differential equation governing volume flow through a pressure-controlled valve, paying particular attention to this rather troublesome transition. A closed-form solution for the time evolution of volume flow is given and used to derive an update for volume flow. The result is a smoother, more accurate, and nearly alias-free transition from open to closed. ``Feathered collisions'' of this nature can refine the sound quality produced by the numerical simulation of beating reeds, such as in clarinets, at typical audio sampling rates.

  11. Cardiac CT angiography in children with congenital heart disease

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-07-15

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

  12. Single-beat noninvasive imaging of ventricular endocardial and epicardial activation in patients undergoing CRT.

    Directory of Open Access Journals (Sweden)

    Thomas Berger

    Full Text Available BACKGROUND: Little is known about the effect of cardiac resynchronization therapy (CRT on endo- and epicardial ventricular activation. Noninvasive imaging of cardiac electrophysiology (NICE is a novel imaging tool for visualization of both epi- and endocardial ventricular electrical activation. METHODOLOGY/PRINCIPAL FINDINGS: NICE was performed in ten patients with congestive heart failure (CHF undergoing CRT and in ten patients without structural heart disease (control group. NICE is a fusion of data from high-resolution ECG mapping with a model of the patient's individual cardiothoracic anatomy created from magnetic resonance imaging. Beat-to-beat endocardial and epicardial ventricular activation sequences were computed during native rhythm as well as during ventricular pacing using a bidomain theory-based heart model to solve the related inverse problem. During right ventricular (RV pacing control patients showed a deterioration of the ventricular activation sequence similar to the intrinsic activation pattern of CHF patients. Left ventricular propagation velocities were significantly decreased in CHF patients as compared to the control group (1.6±0.4 versus 2.1±0.5 m/sec; p<0.05. CHF patients showed right-to-left septal activation with the latest activation epicardially in the lateral wall of the left ventricle. Biventricular pacing resulted in a resynchronization of the ventricular activation sequence and in a marked decrease of total LV activation duration as compared to intrinsic conduction and RV pacing (129±16 versus 157±28 and 173±25 ms; both p<0.05. CONCLUSIONS/SIGNIFICANCE: Endocardial and epicardial ventricular activation can be visualized noninvasively by NICE. Identification of individual ventricular activation properties may help identify responders to CRT and to further improve response to CRT by facilitating a patient-specific lead placement and device programming.

  13. Discrete Scale Invariance in the Cascade Heart Rate Variability Of Healthy Humans

    CERN Document Server

    Lin, D C

    2004-01-01

    Evidence of discrete scale invariance (DSI) in daytime healthy heart rate variability (HRV) is presented based on the log-periodic power law scaling of the heart beat interval increment. Our analysis suggests multiple DSI groups and a dynamic cascading process. A cascade model is presented to simulate such a property.

  14. THE ANALYSIS OF HEART FREQUENCY OF HORSES UNDER LOAD

    Directory of Open Access Journals (Sweden)

    Eva Mlyneková

    2013-02-01

    Full Text Available In our work we analysed the heart frequency of 11 warmblood horses on the load regulator of motion. The test lasted 3 weeks with gradual increase of load. The load was applied only in a step with gradual increase of time of load in up-sloping direction. The mean values of heart frequency of tested horses were within 61 beats/min. At the evaluation of maximum value of heart frequency we detected its twofold increase in comparison with mean values. The maximum rate of heart frequency under load was at the level of 147 beats/min. Detected values were not statistically significant which confirms that the load on tested horses was not causing any physiological changes.

  15. Botox Beats Implant for Urinary Incontinence in Women

    Science.gov (United States)

    ... html Botox Beats Implant for Urinary Incontinence in Women But both have side effects that may affect ... 2016 TUESDAY, Oct. 4, 2016 (HealthDay News) -- For women with bladder incontinence who haven't been helped ...

  16. Modulation of attosecond beating in resonant two-photon ionization

    CERN Document Server

    Galán, Álvaro J; Martín, Fernando

    2014-01-01

    We present a theoretical study of the photoelectron attosecond beating at the basis of RABBIT (Reconstruction of Attosecond Beating By Interference of Two-photon transitions) in the presence of autoionizing states. We show that, as a harmonic traverses a resonance, its sidebands exhibit a peaked phase shift as well as a modulation of the beating frequency itself. Furthermore, the beating between two resonant paths persists even when the pump and the probe pulses do not overlap, thus providing a sensitive non-holographic interferometric means to reconstruct coherent metastable wave packets. We characterize these phenomena quantitatively with a general finite-pulse analytical model that accounts for the effect of both intermediate and final resonances on two-photon processes, at a negligible computational cost. The model predictions are in excellent agreement with those of accurate ab initio calculations for the helium atom in the region of the N=2 doubly excited states.

  17. Taming microwave plasma to beat thermodynamics in CO2 dissociation

    NARCIS (Netherlands)

    van Rooij, G.; van den Bekerom, D.; N. den Harder,; Minea, T.; G. Berden,; Bongers, W.; Engeln, R.; Graswinckel, M.; Zoethout, E.; M. C. M. van de Sanden,

    2015-01-01

    The strong non-equilibrium conditions provided by the plasma phase offer the opportunity to beat traditional thermal process energy efficiencies via preferential excitation of molecular vibrations. Simple molecular physics considerations are presented to explain potential dissociation pathways in a

  18. Illustrated Imaging Essay on Congenital Heart Diseases: Multimodality Approach Part II: Acyanotic Congenital Heart Disease and Extracardiac Abnormalities.

    Science.gov (United States)

    Bhat, Venkatraman; Belaval, Vinay; Gadabanahalli, Karthik; Raj, Vimal; Shah, Sejal

    2016-06-01

    Acyanotic heart disease constitutes a significant majority of patient who may present with non-cardiac symptoms. Either they are detected incidentally or present with respiratory complaints. Equipped with knowledge of anatomy by echocardiography and radiographic methods described in previous part of this presentation, diagnosis may be confidently attempted. On plain radiography acyanotic congenital heart diseases have variable appearance depending upon severity of disease. Cardiac size, chamber enlargement and pulmonary vascular pattern are key elements. Typically left to right shunts with large volume flow are associated with pulmonary plethora. Plain radiography has an important role in detecting manifestation of pulmonary arterial hypertension. Severe stenosis of pulmonary valve is associated with pulmonary oligemia. Small intra-cardiac shunts and anomalies of coronary arteries generally present with normal cardiac size and pulmonary arterial pattern. Disease spectrum presented in this illustration demands thorough scrutiny of pulmonary, osseous and abdominal abnormalities. This section illustrates some commonly encountered spectrum of acyanotic cardiac disease. PMID:27504381

  19. Towards T1-limited magnetic resonance imaging using Rabi beats

    CERN Document Server

    Fedder, H; Rempp, F; Wolf, T; Hemmer, P; Jelezko, F; Wrachtrup, J

    2010-01-01

    Two proof-of-principle experiments towards T1-limited magnetic resonance imaging with NV centers in diamond are demonstrated. First, a large number of Rabi oscillations is measured and it is demonstrated that the hyperfine interaction due to the NV's 14N can be extracted from the beating oscillations. Second, the Rabi beats under V-type microwave excitation of the three hyperfine manifolds is studied experimentally and described theoretically.

  20. Towards T 1-limited magnetic resonance imaging using Rabi beats

    Science.gov (United States)

    Fedder, H.; Dolde, F.; Rempp, F.; Wolf, T.; Hemmer, P.; Jelezko, F.; Wrachtrup, J.

    2011-03-01

    Two proof-of-principle experiments toward T 1-limited magnetic resonance imaging with NV centers in diamond are demonstrated. First, a large number of Rabi oscillations is measured and it is demonstrated that the hyperfine interaction due to the NV's 14N can be extracted from the beating oscillations. Second, the Rabi beats under V-type microwave excitation of the three hyperfine manifolds is studied experimentally and described theoretically.

  1. 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 ...

  2. 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 ...

  3. 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.

  4. Beat-to-beat assessment of left ventricular ejection in atrial fibrillation

    International Nuclear Information System (INIS)

    Beat-to-beat left ventricular ejection was evaluated in a group of 20 patients with chronic atrial fibrillation using a computerized single probe detector. The reference group consisted of 10 patients with sinus rhythm. For each patient 30 successive cardiac cycles were analyzed and the relative variations of four parameters were assessed: R-R interval, diastolic and systolic time intervals, and ejection amplitude, corresponding to the left ventricular stroke volume. The mean variations were respectively 3.4%, 10.4%, 8.4%, and 11.8% in patients with sinus rhythm, and 21.9%, 37.9%, 10.6% and 30.5% in patients with artrial fibrillation. This demonstrates that changes in ejection are mainly related to the duration of the filling phase, with nearly constant systolic times. Correlations between R-R intervals and systolic ejection amplitudes were highly significant (P<0.001) in patients with atrial fibrillation in 85% of cases. This information complements the average ejection fraction obtained from multiple cycle superimposition. (orig.)

  5. Visualizing voltage dynamics in zebrafish heart.

    Science.gov (United States)

    Tsutsui, Hidekazu; Higashijima, Shin-ichi; Miyawaki, Atsushi; Okamura, Yasushi

    2010-06-15

    The zebrafish heart provides a useful vertebrate cardiovascular model with outstanding advantages, including genetic manipulatability, optical accessibility and rapid development. In addition, an emerging topic in cardiotoxicity assay and drug discovery is its use in phenotype-based chemical screening. Here, we report a technique that allows non-invasive voltage mapping in beating heart using a genetically encoded probe for transmembrane potential. Application of the anti-allergy compound astemizole resulted in aberrant propagation of excitation, which accounted for a lack of ventricular contraction. This optical method will provide new opportunities in broad areas of physiological, developmental and pharmacological cardiovascular research. PMID:20421282

  6. Glucagon Increases Beating Rate but Not Contractility in Rat Right Atrium. Comparison with Isoproterenol.

    Directory of Open Access Journals (Sweden)

    Beatriz Merino

    Full Text Available This study evaluated the chronotropic and inotropic responses to glucagon in spontaneously beating isolated right atria of rat heart. For comparison, we also investigated the effects resulting from stimulating β-adrenoceptors with isoproterenol in this tissue. Isoproterenol increased both atrial frequency and contractility but glucagon only enhanced atrial rate. The transcript levels of glucagon receptors were about three times higher in sinoatrial node than in the atrial myocardium. Chronotropic responses to glucagon and isoproterenol were blunted by the funny current (If inhibitor ZD 7288. Inhibitors of protein kinase A, H-89 and KT-5720 reduced the chronotropic response to glucagon but not to isoproterenol. Inhibition of ryanodine receptors and calcium/calmodulin dependent protein kinase II (important regulators of sarcoplasmic reticulum Ca2+ release, with ruthenium red and KN-62 respectively, failed to alter chronotropic responses of either glucagon or isoproterenol. Non selective inhibition of phosphodiesterase (PDE with 3-isobutylmethylxantine or selective inhibition of PDE3 or PDE4 with cilostamide or rolipram respectively did not affect chronotropic effects of glucagon or isoproterenol. Our results indicate that glucagon increases beating rate but not contractility in rat right atria which could be a consequence of lower levels of glucagon receptors in atrial myocardium than in sinoatrial node. Chronotropic responses to glucagon or isoproterenol are mediated by If current but not by sarcoplasmic reticulum Ca2+ release, neither are regulated by PDE activity.

  7. Combining neural networks and ANFIS classifiers for supervised examining of electrocardiogram beats.

    Science.gov (United States)

    Javadi, Mehrdad

    2013-11-01

    Abstract In this paper, the supervised classification of the electrocardiogram (ECG) beats based on the fusion of several intelligent learning machines is described. For classification of ECG heartbeats, first, the QRS complexes are delineated by an efficient algorithm so as to identify the fiducial and J-locations of each complex. For each delineated QRS complex, a feature vector is established based on the geometrical properties of the complex waveform and its associated discrete-wavelet transform. Next, three different multi-layer perceptron back-propagation (MLP-BP) networks are trained with different topologies and intrinsic parameters. Afterwards, the outputs of MLP-BPs are used as the new feature space elements for training three adaptive fuzzy network inference systems (ANFIS) in order to increase the final accuracy. At the end, the outputs of ANFIS classifiers are voted based on majority for each input sample. The method was applied to seven arrhythmias (Normal, LBBB, RBBB, PVC, APB, VE, VF) which belong to the MIT-BIH Arrhythmia Database and the average accuracy value Acc=98.28% was achieved for the beat-level. Also, the proposed method was assessed to five arrhythmias (Normal, LBBB, RBBB, PVC, APB) according to validation standards of the American Heart Association (AHA) at record (subject) level and the average accuracy value Acc=73.39% was achieved. To evaluate performance quality of the new proposed hybrid learning machine, the obtained results were compared with similar peer-reviewed studies in this area. PMID:24044548

  8. 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.

  9. Early repolarization as a predictor of premature ventricular beats.

    Science.gov (United States)

    Matoshvili, Z T; Petriashvili, Sh G; Archadze, A T; Azaladze, I G

    2015-02-01

    Early repolarization pattern (ERP) is a common ECG variant, characterized by J point elevation manifested either as terminal QRS slurring (the transition from the QRS segment to the ST segment) or notching (a positive deflection inscribed on terminal QRS complex) associated with concave upward ST-segment elevation and prominent T waves in at least two contiguous leads. Aim of this observational study was to compare number of premature ventricular beats in the different groups of patients with early repolarization. The result of this observational study shows that there are: 1,74 fold higher number of premature ventricular beats in 41-74 year subgroup VS 19-40 year subgroup; 1,31 fold higher number of premature ventricular beats in male subgroup VS female subgroup (But this difference is not statistically significant, because t=1,49, p=0,141); 2,85 fold higher number of premature ventricular beats in CAD+ERP subgroup VS ERP without CAD subgroup; 1,74 fold higher number of premature ventricular beats in HF+ERP subgroup VS ERP without HF subgroup; 1,81 fold higher number of premature ventricular beats in CAD+ERP subgroup VS CAD without ERP subgroup; 1,58 fold higher number of premature ventricular beats in HF+ERP subgroup VS HF without ERP subgroup; So, CAD+ERP is very arrhythmogenic condition, after this is HF+ERP, Then Age. This study shows that ERP independently increase number of PVB in different groups (CAD, HF). This is principally new and very important result. Also the number of patients is enough to make this conclusion.

  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 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. Rotationally acquired four-dimensional optical coherence tomography of embryonic chick hearts using retrospective gating on the common central A-scan

    DEFF Research Database (Denmark)

    Happel, Christoph M.; Thommes, Jan; Thrane, Lars;

    2011-01-01

    We introduce a new method of rotational image acquisition for four-dimensional (4D) optical coherence tomography (OCT) of beating embryonic chick hearts. The rotational axis and the central A-scan of the OCT are identical. An out-of-phase image sequence covering multiple heartbeats is acquired at.......We demonstrate this approach and provide a video of a beating Hamburger and Hamilton stage 16 embryonic chick heart generated from a 4D OCT data set using rotational image acquisition....

  12. 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

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

    International Nuclear Information System (INIS)

    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

  14. 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.)

  15. J point elevation as a predictor of premature ventricular beats.

    Science.gov (United States)

    Matoshvili, Z; Petriashvili, Sh; Archvadze, A; Azaladze, I

    2014-01-01

    Early repolarization pattern (ERP) is a common ECG variant, characterized by J point elevation manifested either as terminal QRS slurring (the transition from the QRS segment to the ST segment) or notching (a positive deflection inscribed on terminal QRS complex) associated with concave upward ST-segment elevation and prominent T waves in at least two contiguous leads. 36 patients were included in this observation. There are 36 patients (19-68 years old) with early repolarization ECG patterns. All this 36 patients were divided into two groups according to their level of J point elevation. First group consisted of 12 patients with J point elevation ≥0,15 mV; second group - of 24 patients with J point elevation premature ventricular beat during 24 h. Before and during this monitoring patients don't take any antyarrhythmic drugs. In the first group (J point elevation ≥0,15 mV) sum of premature ventricular beats were 27432, in the second group (J point elevation premature ventricular beats were 31 896. The results of this observational study shows that there is 1,72 fold higher number of premature ventricular beats in first group. So, J point elevation equal or more then 0,15 mV, is more arrhythmogenic and induces premature ventricular beats. This is principally new and very important result.

  16. Remote monitoring of heart failure patients.

    Science.gov (United States)

    Bhimaraj, Arvind

    2013-01-01

    "The Teledactyl (Tele, far; Dactyl, finger--from the Greek) is a future instrument by which it will be possible for us to 'feel at a distance.' This idea is not at all impossible, for the instrument can be built today with means available right now. It is simply the well known telautograph, translated into radio terms, with additional refinements. The doctor of the future, by means of this instrument, will be able to feel his patient, as it were, at a distance...The doctor manipulates his controls, which are then manipulated at the patient's room in exactly the same manner. The doctor sees what is going on in the patient's room by means of a television screen." -Hugo Gernsback, Science and Invention Magazine, February 1925 Heart failure continues to be a major burden on our health care system. As the number of patients with heart failure increases, the cost of hospitalization alone is contributing significantly to the overall cost of this disease. Readmission rate and hospital length of stay are emerging as quality markers of heart failure care along with reimbursement policies that force hospitals to optimize these outcomes. Apart from maintaining quality assurance, the disease process of heart failure per-se requires demanding and close attention to vitals, diet, and medication compliance to prevent acute decompensation episodes. Remote patient monitoring is morphing into a key disease management strategy to optimize care for heart failure. Innovative implantable technologies to monitor intracardiac hemodynamics also are evolving, which potentially could offer better and substantial parameters to monitor.

  17. Remote Monitoring of Heart Failure Patients

    Science.gov (United States)

    Bhimaraj, Arvind

    2013-01-01

    “The Teledactyl (Tele, far; Dactyl, finger — from the Greek) is a future instrument by which it will be possible for us to ‘feel at a distance.’ This idea is not at all impossible, for the instrument can be built today with means available right now. It is simply the well known telautograph, translated into radio terms, with additional refinements. The doctor of the future, by means of this instrument, will be able to feel his patient, as it were, at a distance…The doctor manipulates his controls, which are then manipulated at the patient’s room in exactly the same manner. The doctor sees what is going on in the patient’s room by means of a television screen.” —Hugo Gernsback, Science and Invention Magazine, February 1925 Heart failure continues to be a major burden on our health care system. As the number of patients with heart failure increases, the cost of hospitalization alone is contributing significantly to the overall cost of this disease. Readmission rate and hospital length of stay are emerging as quality markers of heart failure care along with reimbursement policies that force hospitals to optimize these outcomes. Apart from maintaining quality assurance, the disease process of heart failure per-se requires demanding and close attention to vitals, diet, and medication compliance to prevent acute decompensation episodes. Remote patient monitoring is morphing into a key disease management strategy to optimize care for heart failure. Innovative implantable technologies to monitor intracardiac hemodynamics also are evolving, which potentially could offer better and substantial parameters to monitor. PMID:23519115

  18. Heart Attack

    Science.gov (United States)

    ... having another heart attack. These medicines include: aspirin, beta blockers, statins, ACE inhibitors and fish oil. Your doctor ... have had a stent placed in your heart. Beta blockers are a group of drugs that lower the ...

  19. Heart Failure

    Science.gov (United States)

    ... blood. In other cases, the heart can't pump blood to the rest of the body with enough ... failure affects the right side, the heart cannot pump enough blood to the lungs, where it picks up oxygen. ...

  20. Heart Attack

    Science.gov (United States)

    ... a million people in the U.S. have a heart attack. About half of them die. Many people have permanent heart damage or die because they don't get ... It's important to know the symptoms of a heart attack and call 9-1-1 if someone ...

  1. Prevention of adenosine A2A receptor activation diminishes beat-to-beat alternation in human atrial myocytes.

    Science.gov (United States)

    Molina, Cristina E; Llach, Anna; Herraiz-Martínez, Adela; Tarifa, Carmen; Barriga, Montserrat; Wiegerinck, Rob F; Fernandes, Jacqueline; Cabello, Nuria; Vallmitjana, Alex; Benitéz, Raúl; Montiel, José; Cinca, Juan; Hove-Madsen, Leif

    2016-01-01

    Atrial fibrillation (AF) has been associated with increased spontaneous calcium release from the sarcoplasmic reticulum and linked to increased adenosine A2A receptor (A2AR) expression and activation. Here we tested whether this may favor atrial arrhythmogenesis by promoting beat-to-beat alternation and irregularity. Patch-clamp and confocal calcium imaging was used to measure the beat-to-beat response of the calcium current and transient in human atrial myocytes. Responses were classified as uniform, alternating or irregular and stimulation of Gs-protein coupled receptors decreased the frequency where a uniform response could be maintained from 1.0 ± 0.1 to 0.6 ± 0.1 Hz; p < 0.01 for beta-adrenergic receptors and from 1.4 ± 0.1 to 0.5 ± 0.1 Hz; p < 0.05 for A2ARs. The latter was linked to increased spontaneous calcium release and after-depolarizations. Moreover, A2AR activation increased the fraction of non-uniformly responding cells in HL-1 myocyte cultures from 19 ± 3 to 51 ± 9 %; p < 0.02, and electrical mapping in perfused porcine atria revealed that adenosine induced electrical alternans at longer cycle lengths, doubled the fraction of electrodes showing alternation, and increased the amplitude of alternations. Importantly, protein kinase A inhibition increased the highest frequency where uniform responses could be maintained from 0.84 ± 0.12 to 1.86 ± 0.11 Hz; p < 0.001 and prevention of A2AR-activation with exogenous adenosine deaminase selectively increased the threshold from 0.8 ± 0.1 to 1.2 ± 0.1 Hz; p = 0.001 in myocytes from patients with AF. In conclusion, A2AR-activation promotes beat-to-beat irregularities in the calcium transient in human atrial myocytes, and prevention of A2AR activation may be a novel means to maintain uniform beat-to-beat responses at higher beating frequencies in patients with atrial fibrillation.

  2. Beat & beyond : memoir, myth and visual arts in women of the beat generation = Más allá del "Beat": memoria, mito y arte visual en las mujeres de la generación beat

    OpenAIRE

    Encarnación Pinedo, Estíbaliz

    2016-01-01

    El objetivo de esta tesis doctoral es revaluar el trabajo de las mujeres de la Generación Beat dentro de un discurso artístico y literario post(Beat) o más allá de lo “Beat.” El capítulo dos, en el que se analizan once memorias, se centra en el dilema entre lo personal y lo literario y sirve para delinear el contexto socio-político y artístico en el que las autoras escribieron. A través del análisis de temas comunes a las distintas memorias (la escritura, los roles de género, y la conexión co...

  3. Continuing studies of the plasma beat wave accelerator

    International Nuclear Information System (INIS)

    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

  4. Superresolution measurement of nanofiber diameter by modes beating

    Science.gov (United States)

    Fenton, E. F.; Solano, P.; Hoffman, J. E.; Orozco, L. A.; Rolston, S. L.; Fatemi, F. K.

    2016-05-01

    Nanofibers are becoming an important tool in quantum information technologies for coupling photonics systems to atomic systems. Nondestructive techniques for characterizing these nanofibers prior to integration into an apparatus are desirable. In this work, we probe the light propagating in a fused silica optical nanofiber (750-nm-diameter) by coupling it evanescently to a 6- μm-diameter microfiber that is scanned along the nanofiber length. This technique is capable of observing all possible beat lengths among different propagating modes. The beat lengths are strongly dependent on the nanofiber diameter and refractive index of the fiber. The steep dependence has enabled measurements of the fiber diameter with sub-Angstrom sensitivity. The diameter extracted from the beat length measurements agrees with a measurement made using scanning electron microscopy. Work supported by NSF.

  5. Annular sizing using real-time three-dimensional intracardiac echocardiography-guided trans-catheter aortic valve replacement

    Science.gov (United States)

    Rendon, Alejandro; Hamid, Tahir; Kanaganayagam, Gajen; Karunaratne, Devinda; Mahadevan, Vaikom S

    2016-01-01

    Objective Transcatheter aortic valve replacement (TAVR) has been established as an alternative therapy for patients with severe aortic stenosis who are unfit for the surgical aortic valve replacements. Pre and periprocedural imaging for the TAVR procedure is the key to procedural success. Currently transesophageal echocardiography (TOE), including real-time three-dimensional (RT-3D) imaging TOE, has been used for peri-interventional monitoring and guidance for TAVR. We describe our initial experience with real-time three-dimensional intracardiac echocardiography (RT-3DICE), imaging technology for the use in the TAVR procedure. Methods We used RT-3DICE using an ACUSON SC2000 2.0v (Siemens Medical Solution), and a 10F AcuNav V catheter (Siemens-Acuson, Inc, Mountain View, California, USA) in addition to preoperative multislice CT (MSCT) in total of five patients undergoing TAVR procedure. Results Aortic annulus and sinus of valsalva diameters were measured using RT-3DICE. Aortic valve measurements obtained using RT-3DICE are comparable to those obtained using MSCT with no significant difference in our patients. Conclusions This small study of five patients shows the safe use of RT-3DICE in TAVR Procedure and may help the procedures performed under local anaesthesia without the need for TOE. PMID:27158522

  6. Non-contact and noise tolerant heart rate monitoring using microwave doppler sensor and range imagery.

    Science.gov (United States)

    Matsunag, Daichi; Izumi, Shintaro; Okuno, Keisuke; Kawaguchi, Hiroshi; Yoshimoto, Masahiko

    2015-01-01

    This paper describes a non-contact and noise-tolerant heart beat monitoring system. The proposed system comprises a microwave Doppler sensor and range imagery using Microsoft Kinect™. The possible application of the proposed system is a driver health monitoring. We introduce the sensor fusion approach to minimize the heart beat detection error. The proposed algorithm can subtract a body motion artifact from Doppler sensor output using time-frequency analysis. The body motion artifact is a crucially important problem for biosignal monitoring using microwave Doppler sensor. The body motion speed is obtainable from range imagery, which has 5-mm resolution at 30-cm distance. Measurement results show that the success rate of the heart beat detection is improved about 75% on average when the Doppler wave is degraded by the body motion artifact.

  7. On readout of vibrational qubits using quantum beats

    International Nuclear Information System (INIS)

    Readout of the final states of qubits is a crucial step towards implementing quantum computation in experiment. Although not scalable to large numbers of qubits per molecule, computational studies show that molecular vibrations could provide a significant (factor 2–5 in the literature) increase in the number of qubits compared to two-level systems. In this theoretical work, we explore the process of readout from vibrational qubits in thiophosgene molecule, SCCl2, using quantum beat oscillations. The quantum beats are measured by first exciting the superposition of the qubit-encoding vibrational states to the electronically excited readout state with variable time-delay pulses. The resulting oscillation of population of the readout state is then detected as a function of time delay. In principle, fitting the quantum beat signal by an analytical expression should allow extracting the values of probability amplitudes and the relative phases of the vibrational qubit states. However, we found that if this procedure is implemented using the standard analytic expression for quantum beats, a non-negligible phase error is obtained. We discuss the origin and properties of this phase error, and propose a new analytical expression to correct the phase error. The corrected expression fits the quantum beat signal very accurately, which may permit reading out the final state of vibrational qubits in experiments by combining the analytic fitting expression with numerical modelling of the readout process. The new expression is also useful as a simple model for fitting any quantum beat experiments where more accurate phase information is desired

  8. Amphibian embryos as a model system for organ engineering: in vitro induction and rescue of the heart anlage.

    Science.gov (United States)

    Grunz, H

    1999-07-01

    Beating hearts can be induced under in vitro conditions when the dorsal blastopore lip (including the zone of Spemann organizer) is treated with Suramin. In contrast, untreated organizer forms dorsal mesodermal derivatives as notochord and somites. When those in vitro produced heart precursor tissues are transplanted ectopically in the posterior trunk area of early larvae, secondary beating heart structures will be formed. Furthermore, the replacement of the heart primordium of the host embryo by heart tissue induced under in vitro conditions will result in the rescue of the heart anlage. This model could be a valuable tool for the study of the multi-step molecular mechanisms of heart structure induction under in vitro conditions and vasculogenesis after transplantation into the host embryo.

  9. 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 St. Jude Medical 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. PMID:26786673

  10. 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.

  11. HEART RETRANSPLANTATION

    Directory of Open Access Journals (Sweden)

    R. Sh. Saitgareev

    2016-01-01

    Full Text Available The number of patients with transplanted heart is continuously increasing; therefore, the number of patients requiring heart retransplantation grows. Analysis of the results of published studies focused on safety of cardiac retransplantation and risk factors for adverse events in perioperative, early and late postoperative periods is presented in our review. The results of published studies suggest that heart retransplantation is the main radical treatment option for cardiac allograft dysfunction, but the results of heart retransplantation are slightly worse than those of primary cardiac transplantation. On the other hand, the favorable long-term prognosis after heart retransplantation should be expected in carefully selected recipients. 

  12. Rotationally acquired 4D-optical coherence tomography of embryonic chick hearts using retrospective gating on the common central A-scan

    DEFF Research Database (Denmark)

    Thommes, Jan; Happel, Christoph M.; Thrane, Lars;

    2010-01-01

    is used for this purpose, e.g. in MRT or CT of human hearts. For visualization of embryonic chick hearts with high-resolution optical coherence tomography (OCT), a gating trigger generated by laser Doppler velocimetry has been successfully demonstrated (1). But this takes time and adds to system......In vivo analysis of cardiac physiology and non-invasive imaging of the beating early embryonic heart in 2 and 3D remain a challenge in cardiovascular development research. 3D-imaging of the beating heart relies on gating of the acquired images according to the cardiac cycle. Mostly ECG triggering...

  13. Rotationally acquired 4D-optical coherence tomography of embryonic chick hearts using retrospective gating on the common central A-scan

    OpenAIRE

    Thommes, Jan; Happel, Christoph M.; Thrane, Lars; Yelbuz, T. Mesud

    2010-01-01

    In vivo analysis of cardiac physiology and non-invasive imaging of the beating early embryonic heart in 2 and 3D remain a challenge in cardiovascular development research. 3D-imaging of the beating heart relies on gating of the acquired images according to the cardiac cycle. Mostly ECG triggering is used for this purpose, e.g. in MRT or CT of human hearts. For visualization of embryonic chick hearts with high-resolution optical coherence tomography (OCT), a gating trigger generated by laser D...

  14. Can We Learn to Beat the Best Stock

    CERN Document Server

    Borodin, A; Gogan, V; 10.1613/jair.1336

    2011-01-01

    A novel algorithm for actively trading stocks is presented. While traditional expert advice and "universal" algorithms (as well as standard technical trading heuristics) attempt to predict winners or trends, our approach relies on predictable statistical relations between all pairs of stocks in the market. Our empirical results on historical markets provide strong evidence that this type of technical trading can "beat the market" and moreover, can beat the best stock in the market. In doing so we utilize a new idea for smoothing critical parameters in the context of expert learning.

  15. The load-response of the flagellar beat

    CERN Document Server

    Klindt, Gary S; Wanger, Christian; Friedrich, Benjamin M

    2016-01-01

    Cilia and flagella exhibit regular bending waves that perform mechanical work on the surrounding fluid, to propel cellular swimmers and pump fluids inside organisms. Here, we quantify a force-velocity relationship of the beating flagellum, by exposing flagellated \\emph{Chlamydomonas} cells to controlled microfluidic flows. A simple theory of flagellar limit-cycle oscillations, calibrated by measurements in the absence of flow, reproduces this relationship quantitatively. We derive a link between the chemo-mechanical efficiency of the flagellar beat and its ability to synchronize to oscillatory flows.

  16. Intra-cardiac distribution of late gadolinium enhancement in cardiac sarcoidosis and dilated cardiomyopathy

    Science.gov (United States)

    Sano, Makoto; Satoh, Hiroshi; Suwa, Kenichiro; Saotome, Masao; Urushida, Tsuyoshi; Katoh, Hideki; Hayashi, Hideharu; Saitoh, Takeji

    2016-01-01

    Cardiac involvement of sarcoid lesions is diagnosed by myocardial biopsy which is frequently false-negative, and patients with cardiac sarcoidosis (CS) who have impaired left ventricular (LV) systolic function are sometimes diagnosed with dilated cardiomyopathy (DCM). Late gadolinium enhancement (LE) in magnetic resonance imaging is now a critical finding in diagnosing CS, and the novel Japanese guideline considers myocardial LE to be a major criterion of CS. This article describes the value of LE in patients with CS who have impaired LV systolic function, particularly the diagnostic and clinical significance of LE distribution in comparison with DCM. LE existed at all LV segments and myocardial layers in patients with CS, whereas it was localized predominantly in the midwall of basal to mid septum in those with DCM. Transmural (nodular), circumferential, and subepicardial and subendocardial LE distribution were highly specific in patients with CS, whereas the prevalence of striated midwall LE were high both in patients with CS and with DCM. Since sarcoidosis patients with LE have higher incidences of heart failure symptoms, ventricular tachyarrhythmia and sudden cardiac death, the analyses of extent and distribution of LE are crucial in early diagnosis and therapeutic approach for patients with CS. PMID:27721933

  17. Beating the odds--surviving extreme hyperkalemia.

    Science.gov (United States)

    Muck, Philip M; Letterer, Sebastian; Lindner, Ulrich; Lehnert, Hendrik; Haas, Christian Stefan

    2012-01-01

    Severe hyperkalemia (>7 mmol/L) is a medical emergency because of possible fatal arrhythmias. We here report the case of a 58-year-old woman surviving extreme hyperkalemia (>10 mmol/L). The patient with a history of congestive heart failure, a DDD pacemaker and mild chronic renal insufficiency was admitted with progressive weakness and sudden onset of hypotension and bradycardia in the absence of any pacemaker action. Laboratory tests revealed an extreme serum potassium level of 10.1 mmol/L, with a slightly elevated serum creatinine of 149 μmol/L. Treatment with norepinephrine, sodium bicarbonate, and insulin improved both the hemodynamic situation and the serum potassium with subsequent regaining pacemaker actions even before additional hemodialysis normalized the potassium level. A thorough investigation demonstrated that several mechanisms contributed to the extreme potassium level: urinalysis and a low transtubular potassium gradient in the presence of metabolic acidosis with normal anion gap pointed to preexisting interstitial nephritis, with renal tubular acidosis type IV as the predisposing factor, whereas several drugs and acute impairment of renal function contributed to the dangerous situation. Despite the odds for fatal outcome, the patient recovered completely, and long-term management was initiated to prevent recurrent hyperkalemia.

  18. Analysis of ependymal ciliary beat pattern and beat frequency using high speed imaging: comparison with the photomultiplier and photodiode methods

    Directory of Open Access Journals (Sweden)

    O'Callaghan Chris

    2012-06-01

    Full Text Available Abstract Background The aim of this study was to compare beat frequency measurements of ependymal cilia made by digital high speed imaging to those obtained using the photomultiplier and modified photodiode techniques. Using high speed video analysis the relationship of the power and recover strokes was also determined. Methods Ciliated strips of ependyma attached to slices from the brain of Wistar rats were incubated at 30°C and observed using a ×50 water immersion lens. Ciliary beat frequency was measured using each of the three techniques: the high speed video, photodiode and photomultiplier. Readings were repeated after 30 minutes incubation at 37°C. Ependymal cilia were observed in slow motion and the precise movement of cilia during the recovery stroke relative to the path travelled during the power stroke was measured. Results The mean (95% confidence intervals beat frequencies determined by the high speed video, photomultiplier and photodiode at 30°C were 27.7 (26.6 to 28.8, 25.5 (24.4 to 26.6 and 20.8 (20.4 to 21.3 Hz, respectively. The mean (95% confidence intervals beat frequencies determined by the high speed video, photomultiplier and photodiode at 37°C were 36.4 (34 to 39.5, 38.4 (36.8 to 39.9 and 18.8 (16.9 to 20.5 Hz. The inter and intra observer reliability for measurement of ciliary beat frequency was 3.8% and 1%, respectively. Ependymal cilia were observed to move in a planar fashion during the power and recovery strokes with a maximum deviation to the right of the midline of 12.1(11.8 to 13.0° during the power stroke and 12.6(11.6 to 13.6° to the left of the midline during the recovery stroke. Conclusion The photodiode technique greatly underestimates ciliary beat frequency and should not be used to measure ependymal ciliary beat frequency at the temperatures studied. Ciliary beat frequency from the high speed video and photomultiplier techniques cannot be used interchangeably. Ependymal cilia had minimal deviation to

  19. Investigation on laser accelerators. Plasma beat wave accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Miura, Akihiko; Miyamoto, Yasuaki; Hagiwara, Masayoshi; Suzuki, Mitsutoshi; Sudo, Osamu [Power Reactor and Nuclear Fuel Development Corp., Tokai, Ibaraki (Japan). Tokai Works

    1998-04-01

    Laser accelerator technology has characteristics of high energy, compact, short pulse and high luminescence{center_dot}low emittance. This means potential many applications in wide ranges of fields as well as high energy and nuclear physics. High power short laser pulses are injected to a plasma in the typical example of laser accelerators. Large electric fields are induced in the plasma. Electrons in the plasma are accelerated with the ponderomotive force of the electric field. The principles of interaction on beat wave, wakefield accelerators, inverse free electron laser and inverse Cherenkov radiation are briefly introduced. The overview of plasma beat wave accelerator study is briefly described on the programs at Chalk River Laboratories(Canada), UCLA(USA), Osaka Univ. (Japan) and Ecole Polytechnique (France). Issues of the plasma beat wave accelerator are discussed from the viewpoint of application. Existing laser technologies of CO{sub 2}, YAG and YFL are available for the present day accelerator technology. An acceleration length of beat wave interaction is limited due to its phase condition. Ideas on multi-staged acceleration using the phasing plasma fiber are introduced. (Y. Tanaka)

  20. Theory of beat wave excitation in an inhomogeneous plasma

    International Nuclear Information System (INIS)

    The theory of beat wave excitation in a slightly inhomogeneous plasma is presented. While the theory is general it applies directly to the experiments performed in Alaska by the ionospheric heating facilities HIPAS [High Power Auroral Simulation, Radio Sci. 25, 1269 (1990)] and HAARP [High Frequency Active Auroral Research Project, Geophys. Res. Lett. 25, 257 (1998)]. A ray tracing (WKB) formalism appropriate for computations is developed. The computational implementation of this formalism and extensive results will be presented in a follow up to this paper. Also the beat wave excitation of upper-hybrid waves is investigated analytically. The complicated trajectories of these waves in the plasma are described. When this beat wave reaches the plasma wave resonance it can, in the HIPAS-HAARP experiments, attain nonlinear amplitude. The electrostatic upper-hybrid waves are trapped around the density maximum of the ionosphere. This trapping is investigated in detail. Beat wave pumping of the trapped modes is possible using HAARP and HIPAS or with split beams from HAARP

  1. 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…

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

    International Nuclear Information System (INIS)

    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)

  3. Perceptions of Conducting: Accuracy in Detecting Modulated Beat.

    Science.gov (United States)

    Brittin, Ruth V.

    1992-01-01

    Presents findings of a study of viewers' ability to detect changes in conducting beat patterns. Reports that music education majors were significantly better able to detect tempo decreases than increases and better able than nonmajors to detect decreases. Indicates that nonmajors were better able than majors to identify tempo increases. (SG)

  4. 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.

  5. Reduced Order Dead-Beat Observers for a Bioreactor

    CERN Document Server

    Karafyllis, Iasson

    2010-01-01

    This paper studies the strong observability property and the reduced-order dead-beat observer design problem for a continuous bioreactor. New relationships between coexistence and strong observability, and checkable sufficient conditions for strong observability, are established for a chemostat with two competing microbial species. Furthermore, the dynamic output feedback stabilization problem is solved for the case of one species.

  6. Subdividing the beat: auditory and motor contributions to synchronization

    NARCIS (Netherlands)

    Loehr, J.D.; Palmer, C.

    2009-01-01

    THE CURRENT STUDY EXAMINED HOW AUDITORY AND kinematic information influenced pianists' ability to synchronize musical sequences with a metronome. Pianists performed melodies in which quarter-note beats were subdivided by intervening eighth notes that resulted from auditory information (heard tones),

  7. Factors associated with wife beating in Egypt: Analysis of two surveys (1995 and 2005)

    OpenAIRE

    Dhaher Enas; Labeeb Shokria; Mikolajczyk Rafael T; Akmatov Manas K; Khan Md Mobarak

    2008-01-01

    Abstract Background Wife beating is an important public health problem in many developing countries. We assessed the rates of wife beating and examined factors associated with wife beating in 1995 and 2005 in Egypt. Methods We used data from two Demographic and Health Surveys (DHS) conducted in Egypt in 1995 and 2005 using multistage household sampling. Data related to wife beating included information from 7122 women in 1995 and 5612 women in 2005. Logistic regression was used to analyze fac...

  8. Finding the beat: a neural perspective across humans and non-human primates

    OpenAIRE

    Merchant, Hugo; Grahn, Jessica; Trainor, Laurel; Rohrmeier, Martin; Fitch, W. Tecumseh

    2015-01-01

    Humans possess an ability to perceive and synchronize movements to the beat in music (‘beat perception and synchronization’), and recent neuroscientific data have offered new insights into this beat-finding capacity at multiple neural levels. Here, we review and compare behavioural and neural data on temporal and sequential processing during beat perception and entrainment tasks in macaques (including direct neural recording and local field potential (LFP)) and humans (including fMRI, EEG and...

  9. Types of Heart Surgery

    Science.gov (United States)

    ... or heart wall with a patch or graft. Heart Transplant A heart transplant is surgery to remove a person's diseased heart ... a healthy heart from a deceased donor. Most heart transplants are done on patients who have end-stage ...

  10. Hypoplastic left heart syndrome

    Science.gov (United States)

    HLHS; Congenital heart - hypoplastic left heart; Cyanotic heart disease - hypoplastic left heart ... Hypoplastic left heart is a rare type of congenital heart disease. It is more common in males than in ...

  11. Heart pacemaker

    Science.gov (United States)

    ... Elsevier Saunders; 2015:chap 36. Read More Arrhythmias Atrial fibrillation or flutter Cardiac ablation procedures Heart failure - overview Implantable cardioverter-defibrillator Sick sinus syndrome Wolff- ...

  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. Characterization of Left Atrial Tachyarrhythmias in Patients Following Atrial Fibrillation Ablation: Correlation of surface ECG with Intracardiac Mapping

    Directory of Open Access Journals (Sweden)

    Sanjay Dixit

    2010-05-01

    Full Text Available With expected success rates in excess of 80% for achieving long term arrhythmia control, catheter based ablation has become a popular treatment strategy in the management of patients with atrial fibrillation (AF. However, the success of AF ablation has been tempered by the occurrence of post procedure left atrial tachycardias and / or flutters, which can be seen in up to 30% of the patients. These arrhythmias are perpetuated either due to abnormalities of impulse formation (abnormal automaticity / triggered activity, or abnormalities of impulse conduction (micro / macroreentry. Regardless of the underlying mechanism, these tachycardias manifest distinct “P” or flutter waves on the surface ECG, recognition of which may facilitate their characterization / localization. However, because of the frequent overlap in the morphology of P waves, intracardiac mapping is often the only way to distinguish them apart. This is accomplished using a combination of activation, entrainment and electroanatomic mapping techniques. Tachycardias resulting from abnormalities of impulse formation and / or microreentry are characteristically focal and usually confined in and around pulmonary vein (PV segments which have reconnected (septal aspect of right PVs and anterior aspect of left PVs. In contrast, macroreentrant tachycardias manifest a large circuit dimension involving zone(s of slow conduction. These are most commonly seen to occur around the mitral valve but can develop in any part of the left atrium where “gaps” across prior ablation lesion sets create altered conduction. Successful ablation of focal tachycardias is usually accomplished by isolating the reconnected PV segment(s. In case of macroreentrant arrhythmias however, a more extensive ablation approach is typically required in order to achieve conduction block across isthmus of the circuit. Using these strategies, the majority of left atrial tachycardias occurring post AF ablation can be

  14. Ambulatory instrument for monitoring indirect beat-to-beat blood pressure in superficial temporal artery using volume-compensation method.

    Science.gov (United States)

    Tanaka, S; Yamakoshi, K

    1996-11-01

    A portable instrument, based on a volume-compensation technique, is designed for ambulatory monitoring of indirect beat-to-beat blood pressure (BP) in the superficial temporal artery. The instrument consists of a small disc-type cuff and a portable unit carried by the subject. Several components are integrated in the cuff for applying counter-pressure to the artery, i.e. a reflectance-type photo-plethysmographic sensor for arterial volume detection, a pressure sensor for cuff pressure Pc measurement and a nozzle flapper-type- electro-pneumatic convertor for controlling Pc. The portable unit includes volume servo control circuitry and a microprocessor-based signal-processing and recording unit. This automatically performs all the necessary measurement procedures and stores into a memory IC element the processed systolic, mean and diastolic blood pressure data, together with pulse intervals on a beat-to-beat basis from the servo-controlled Pc (indirectly measured BP waveform). With this instrument, momentary changes in BP during ambulatory situations such as bicycle ergometer exercise and daily activities including motorway driving are successfully recorded. From the results of simultaneous measurement of the subject's posture changes, the effect of posture change on blood pressure, e.g. baroreceptor-cardiac reflex, is also clearly demonstrated.

  15. Use of seismocardiogram for the beat-to-beat assessment of the Pulse Transit Time: A pilot study.

    Science.gov (United States)

    Di Rienzo, Marco; Vaini, Emanuele; Lombardi, Prospero

    2015-08-01

    We propose a new methodology for the estimation of Pulse Transit Time, PTT, based on the use of the seismocardiogram for the identification of the aortic valve opening, AO. This method has been implemented to obtain a first description of the AO-derived PTT beat-to-beat variability at rest and during the recovery after a cycloergometer exercise at 25W and 100W, its relation with systolic blood pressure, S(BP), and its difference with respect to variability of the Pulse Arrival Time, PAT (i.e. the BP transit time estimated by considering the ECG R peak instead of AO as proximal site). Our preliminary data indicate that 1) the fast components of the PTT variability are only marginally influenced by respiration; 2) only the slower components of the PTT variability are correlated with systolic BP; 3) major differences exist in the dynamics of PTT and PAT, being PAT variability significantly larger and importantly influenced by the beat-to-beat changes occurring in the Pre Ejection Period. PMID:26737949

  16. A review of beat-to-beat vectorcardiographic (VCG) parameters for analyzing repolarization variability in ECG signals.

    Science.gov (United States)

    Hasan, Muhammad A; Abbott, Derek

    2016-02-01

    Elevated ventricular repolarization lability is believed to be linked to the risk of ventricular tachycardia/ventricular fibrillation. However, ventricular repolarization is a complex electrical phenomenon, and abnormalities in ventricular repolarization are not completely understood. To evaluate repolarization lability, vectorcardiography (VCG) is an alternative approach where the electrocardiographic (ECG) signal can be considered as possessing both magnitude and direction. Recent research has shown that VCG is advantageous over ECG signal analysis for identification of repolarization abnormality. One of the key reasons is that the VCG approach does not rely on exact identification of the T-wave offset, which improves the reproducibility of the VCG technique. However, beat-to-beat variability in VCG is an emerging area for the investigation of repolarization abnormality though not yet fully realized. Therefore, the purpose of this review is to explore the techniques, findings, and efficacy of beat-to-beat VCG parameters for analyzing repolarization lability, which may have potential utility for further study. PMID:25992510

  17. Modelling a Parasystolic Rhythm in a Heart Transplanted Patient

    CERN Document Server

    Costa, M; Santiago, T; Rebocho, M J; Melo, J; Ducla-Soares, E; Santiago, Teresa

    1999-01-01

    A parasystole from a heart transplanted patient was analysed via the beat to beat - RR interval time series obtained from the electrocardiogram (ECG). The dysrhythmia, resulting from the coexistence of two pacemakers, the sinus node and an ectopic focus, presents distinctive regular patterns with transitions from one pattern to another occurring abruptly. It is shown that the parasystolic rhythm can be simulated by a model involving two oscillators firing at fixed rates, under the restriction that neither is allowed to fire during the other's refractory period. We found that the structure of the generated RR time series is essentially determined by the ratio of the period of the two oscillators. In the case of the heart transplanted patient that has a small heart rate variability as a result of heart denervation, the model could predict the sequence of RR intervals over a considerable period of time (~ 80 beats with an error < 6%). From a physiological point of view, our results imply that the interaction ...

  18. Heart rate detection from an electronic weighing scale

    International Nuclear Information System (INIS)

    We propose a novel technique for beat-to-beat heart rate detection based on the ballistocardiographic (BCG) force signal from a subject standing on a common electronic weighing scale. The detection relies on sensing force variations related to the blood acceleration in the aorta, works even if wearing footwear and does not require any sensors attached to the body because it uses the load cells in the scale. We have devised an approach to estimate the sensitivity and frequency response of three commercial weighing scales to assess their capability to detect the BCG force signal. Static sensitivities ranged from 490 nV V−1 N−1 to 1670 nV V−1 N−1. The frequency response depended on the subject's mass but it was broad enough for heart rate estimation. We have designed an electronic pulse detection system based on off-the-shelf integrated circuits to sense heart-beat-related force variations of about 0.24 N. The signal-to-noise ratio of the main peaks of the force signal detected was higher than 30 dB. A Bland–Altman plot was used to compare the RR time intervals estimated from the ECG and BCG force signals for 17 volunteers. The error was ±21 ms, which makes the proposed technique suitable for short-term monitoring of the heart rate

  19. Cortisol release, heart rate and heart rate variability in the horse and its rider: different responses to training and performance.

    Science.gov (United States)

    von Lewinski, Mareike; Biau, Sophie; Erber, Regina; Ille, Natascha; Aurich, Jörg; Faure, Jean-Michel; Möstl, Erich; Aurich, Christine

    2013-08-01

    Although some information exists on the stress response of horses in equestrian sports, the horse-rider team is much less well understood. In this study, salivary cortisol concentrations, heart rate (HR) and heart rate variability (HRV), SDRR (standard deviation of beat-to-beat interval) and RMSSD (root mean square of successive beat-to-beat intervals) were analysed in horses and their riders (n=6 each) at a public performance and an identical rehearsal that was not open to the public. Cortisol concentrations increased in both horses and riders (P<0.001) but did not differ between performance and rehearsal. HR in horses and riders increased during the rehearsal and the public performance (P<0.001) but the increase in HR was more pronounced (P<0.01) in riders than in their horses during the public performance (from 91 ± 10 to 150 ± 15 beats/min) compared to the rehearsal (from 94 ± 10 to 118 ± 12 beats/min). The SDRR decreased significantly during the equestrian tasks in riders (P<0.001), but not in their horses. The RMSSD decreased in horses and riders (P<0.001) during rehearsal and performance, indicating a decrease in parasympathetic tone. The decrease in RMSSD in the riders was more pronounced (P<0.05) during the performance (from 32.6 ± 6.6 to 3.8 ± 0.3 ms) than during the rehearsal (from 27.5 ± 4.2 to 6.6 ± 0.6 ms). The study has shown that the presence of spectators caused more pronounced changes in cardiac activity in the riders than it did in their horses.

  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. PMID:21805898

  1. Heart failure

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    970284 Effects of enalapril on heart rate variabilityin patients with congestive heart failure. ZHANGYouhua(章友华), et a1. Dept Cardiol, Cardiovasc Instit& Fuwai Hosp, CAMS & PUMC, Beijing, 100037. ChinCir J 1996; 11(2): 729-732.

  2. Artificial Heart Fluid Dynamics.

    Science.gov (United States)

    Mussivand, Tofigh Varcaneh

    Flow characteristics within pneumatic, pulsatile, and pusher plate prosthetic hearts were studied. The blood pumps evaluated were duplicates of pumps used for in vivo calf and for clinical implantation at the Cleveland Clinic Foundation. Human dura mater bioprosthetic, caged disk, and Bjork-Shiley tilting disk valves were employed in the pumps. Dual camera video tape and synchronized still photography were used to study flow patterns. Diffused light and a planar laser source provided illumination. The laser light was fanned into a plane with a thickness of 0.2 mm to 10 mm. Magnesium oxide and Amberlite particles were used as tracers. Aqueous-glycerol, aqueous-sucrose solutions and mineral oil were used as blood analog fluids. Inflow, outflow, drive, and afterload pressures, diaphragm motion, cardiac output, and heart rate were measured and recorded. An electrical circuit was developed to synchronize pump diaphragm motion with captured images of flow trajectories. After digitizing the trajectories, velocities, global and local turbulence, and shear stresses were obtained. Disturbed and recirculating zones were identified. Qualitative and quantitative analyses were performed using data obtained from the digitization of flow trajectories. Simultaneous turbulence and stasis were observed during most phases of the cardiac cycles in all the pumps tested. A maximum Reynold's shear stress of 2889 dynes/cm ^2 occurred at 120 beats per minute (bpm). The peak velocity was 146 cm/sec during systole. The identified regions of recirculation, low velocity and disturbed flow were shown to correlate with thrombosed areas of explanted blood pumps. The maximum calculated turbulence intensity was 106 cm/sec which occurred at 120 bpm during systole.

  3. Optimal image reconstruction phase at low and high heart rates in dual-source CT coronary angiography

    OpenAIRE

    Araoz, Philip A; Kirsch, Jacobo; Primak, Andrew N.; Braun, Natalie N.; Saba, Osama; Williamson, Eric E.; Harmsen, W. Scott; Mandrekar, Jayawant N.; McCollough, Cynthia H.

    2009-01-01

    The purpose of this study was to determine the cardiac phase having the highest coronary sharpness for low and high heart rate patients scanned with dual source CT (DSCT) and to compare coronary image sharpness over different cardiac phases. DSCT coronary CT scans for 30 low heart rate (≤ 70 beats per minute- bpm) and 30 high heart rate (>70 bpm) patients were reconstructed into different cardiac phases, starting at 30% and increasing at 5% increments until 70%. A blinded observer graded imag...

  4. Entwicklung und Charakterisierung eines Vierkammer-Working-Hearts zur Untersuchung eines neuen Verfahrens des EKG-Mappings

    OpenAIRE

    Stahn, Romana Melanie

    2010-01-01

    Carried out within the project of the German Research Foundation (DFG) “ECG Mapping Proceedings on a Heart Surface Defined by Ultrasound” (He 1669/11), this study aimed at developing and characterising an isolated heart model. In particular, basic conditions for a perfusion with preferable physiological cardiac activity should be established. In order to validate a clinically used ECG mapping system, a model of an independently beating and perfused heart had to be developed, aiming at reco...

  5. Heart rate and heart rate variability responses to Tai Chi and jogging in Beijing and Graz

    Directory of Open Access Journals (Sweden)

    Gerhard Litscher

    2011-02-01

    Full Text Available Background: 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. Aims: The goal of this study was to demonstrate heart rate and heart rate variability analysis for the first time during Tai Chi and jogging. Volunteers and Methods: 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. Results: 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. Conclusions: 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.

  6. Heart rate and heart rate variability responses to Tai Chi and jogging in Beijing and Graz

    Directory of Open Access Journals (Sweden)

    Gerhard Litscher

    2011-01-01

    Full Text Available Background : 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. Aims : The goal of this study was to demonstrate heart rate and heart rate variability analysis for the first time during Tai Chi and jogging. Volunteers and Methods : 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. Results : 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. Conclusions : 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.

  7. Simple, heart-smart substitutions

    Science.gov (United States)

    Coronary artery disease - heart smart substitutions; Atherosclerosis - heart smart substitutions; Cholesterol - heart smart substitutions; Coronary heart disease - heart smart substitutions; Healthy diet - heart ...

  8. First Beta-Beating Measurement in the LHC

    CERN Document Server

    Aiba, M; Franchi, A; Giovannozzi, M; Kain, V; Morita, A; Tomás, R; Vanbavinckhove, G; Wenninger, J

    2009-01-01

    This note reports on the first LHC beta-beating and coupling measurements. Thanks to an excellent functioning of the BPM system and the related software, injection oscillations were recorded for the first 90 turns at all BPMs of Beam 2. Three different algorithms are used to measure the optics parameters from the BPM data. All algorithms show consistent measurements but feature different accuracy. The Singular Value Decomposition (SVD) approach shows a high resolution despite the limited number of turns. The vertical beta-beating is observed to be about a factor of two larger than in the horizontal plane. This asymetry is partly due to sextupoles misalignments but also suggests the possible existance of focusing errors at defocussing locations. Rather large coupling is observed since no skew quadrupole was excited at the time of the data acquisition. We also report a list of suspected malfunctioning BPMs identified through various analyses.

  9. Emergence of Synchronized Beating during the Regrowth of Eukaryotic Flagella

    Science.gov (United States)

    Goldstein, Raymond E.; Polin, Marco; Tuval, Idan

    2011-09-01

    A fundamental issue in the biology of eukaryotic flagella is the origin of synchronized beating observed in tissues and organisms containing multiple flagella. Recent studies of the biflagellate unicellular alga Chlamydomonas reinhardtii provided the first evidence that the interflagellar coupling responsible for synchronization is of hydrodynamic origin. To investigate this mechanism in detail, we study here synchronization in Chlamydomonas as its flagella slowly regrow after mechanically induced self-scission. The duration of synchronized intervals is found to be strongly dependent on flagellar length. Analysis within a stochastic model of coupled phase oscillators is used to extract the length dependence of the interflagellar coupling and the intrinsic beat frequencies of the two flagella. Physical and biological considerations that may explain these results are proposed.

  10. A waveguide polarization toolset design based on mode beating

    OpenAIRE

    Hutchings, D.C.; Holmes, B.M.

    2011-01-01

    A toolset of waveguide elements is examined, which can be combined to produce polarization functional devices in a single contiguous waveguide. In particular, waveguide implementations of an optical isolator and a polarization modulator are discussed. The waveguide elements, i.e., quasi-phase-matched nonreciprocal polarization mode converter, reciprocal polarization mode converter (R-PMC), and a differential phase shifter, are all based on mode beating. A universal 3-dB R-PMC specification is...

  11. Observation of chaotic beats in a driven memristive Chua's circuit

    OpenAIRE

    Ahamed, A. Ishaq; Srinivasan, K.; Murali, K.; Lakshmanan, M.

    2010-01-01

    In this paper, a time varying resistive circuit realising the action of an active three segment piecewise linear flux controlled memristor is proposed. Using this as the nonlinearity, a driven Chua's circuit is implemented. The phenomenon of chaotic beats in this circuit is observed for a suitable choice of parameters. The memristor acts as a chaotically time varying resistor (CTVR), switching between a less conductive OFF state and a more conductive ON state. This chaotic switching is govern...

  12. The art equipment for measuring the horse’s heart rate

    Directory of Open Access Journals (Sweden)

    F. Cus

    2010-07-01

    Full Text Available Purpose: of this paper: Heart rate is a reliable indicator of the stress. Non-invasive methods have advantage over the methods that have a negative influence on the condition of an animal. When breeding sport horses, which undergo stressful training every day, it is required, from an ethical aspect, to monitor their capabilities by using most advanced electronic devices Polar Sport Tester and Polar Equine RS800cx G3.Design/methodology/approach: The original Polar ProTrainer 5 Equine edition software facilitates the analysis of individual training phases and gives the number of heart beats, average heart rate, average speed and distance covered in individual training phases.Findings: Heart rate increased, in warming up phase, from the value associated with a resting horse (30 to 40 bpm approximately in one minute, while, during the slow cooling down phase, ten minutes were required for the heart rate to reach the afore-mentioned value. During quick trotting heart rate are 112 heart beats per minute, while during steeplechase phase, it increased to the value of 160 to 170 heart beats per minute.Research limitations/implications: To receive heart rate without disturbances already we moisten the skin on the contact spots, using a mixture of water and electrolytes (Salvana Nutrilyt. Placing receiver on the saddle close by the T56H transmitter was the optimal choice.Practical implications: Modern equipment makes monitoring the horse’s heart rate accurately and to perform, safely and without disturbances, exercises required during training. It also checks the heart rate, which indicates the horse’s health.Originality/value: Polar Sport Tester and Polar Equine RS800cx G3 are state of the art products that facilitate the receipt of the horse’s heart rate signals. The accuracy of the acquired results can be compared with those obtained with ECG measurements.

  13. Individual-Specific, Beat-to-beat Trending of Significant Human Blood Loss: The Compensatory Reserve.

    Science.gov (United States)

    Convertino, Victor A; Howard, Jeffrey T; Hinojosa-Laborde, Carmen; Cardin, Sylvain; Batchelder, Paul; Mulligan, Jane; Grudic, Gregory Z; Moulton, Steven L; MacLeod, David B

    2015-08-01

    Current monitoring technologies are unable to detect early, compensatory changes that are associated with significant blood loss. We previously introduced a novel algorithm to calculate the Compensatory Reserve Index (CRI) based on the analysis of arterial waveform features obtained from photoplethysmogram recordings. In the present study, we hypothesized that the CRI would provide greater sensitivity and specificity to detect blood loss compared with traditional vital signs and other hemodynamic measures. Continuous noninvasive vital sign waveform data, including CRI, photoplethysmogram, heart rate, blood pressures, SpO2, cardiac output, and stroke volume, were analyzed from 20 subjects before, during, and after an average controlled voluntary hemorrhage of ∼1.2 L of blood. Compensatory Reserve Index decreased by 33% in a linear fashion across progressive blood volume loss, with no clinically significant alterations in vital signs. The receiver operating characteristic area under the curve for the CRI was 0.90, with a sensitivity of 0.80 and specificity of 0.76. In comparison, blood pressures, heart rate, SpO2, cardiac output, and stroke volume had significantly lower receiver operating characteristic area under the curve values and specificities for detecting the same volume of blood loss. Consistent with our hypothesis, CRI detected blood loss and restoration with significantly greater specificity than did other traditional physiologic measures. Single measurement of CRI may enable more accurate triage, whereas CRI monitoring may allow for earlier detection of casualty deterioration. PMID:25565640

  14. 31P-NMR analysis of congestive heart failure in the SHHF/Mcc-facp rat heart.

    Science.gov (United States)

    Michael O'Donnell, J; Narayan, P; Bailey, M Q; Abduljalil, A M; Altschuld, R A; McCune, S A; Robitaille, P M

    1998-02-01

    31P-NMR was used to monitor myocardial bioenergetics in compensated and failing SHHF/MCC-fa(cp) (SHF) rat hearts. The SHHF/Mcc-fa(cp) (spontaneous hypertension and heart failure) rat is a relatively new genetic model in which all individuals spontaneously develop congestive heart failure, most during the second year of life. Failing SHF rat hearts displayed a pronounced decrease in resting PCr:ATP ratios (Ppressure products (RRP, mmHg X beats/min) from 44.5+/-1.4 to 66.6+/-3. 4 K with dobutamine infusion, whereas hearts in end-stage failure were able to increase their RPP from baseline values of 27+/-4 K to only 37+/-7 K. The data indicate that a pronounced decline in PCr and total creatine signals the transition from compensatory hypertrophy to decompensation and failure in the SHF rat model of hypertensive cardiomyopathy. PMID:9515000

  15. Moving to the beat and singing are linked in humans

    Directory of Open Access Journals (Sweden)

    Simone eDalla Bella

    2015-12-01

    Full Text Available The abilities to sing and to move to the beat of a rhythmic auditory stimulus emerge early during development, and both engage perceptual, motor, and sensorimotor processes. These similarities between singing and synchronization to a beat may be rooted in biology. Patel (2008 has suggested that motor synchronization to auditory rhythms may have emerged during evolution as a byproduct of selection for vocal learning (vocal learning and synchronization hypothesis. This view predicts a strong link between vocal performance and synchronization skills in humans. Here we tested this prediction by asking occasional singers to tap along with auditory pulse trains and to imitate familiar melodies. Both vocal imitation and synchronization skills were measured in terms of accuracy and precision or consistency. Accurate and precise singers tapped more in the vicinity of the pacing stimuli (i.e., they were more accurate than inaccurate and imprecise singers. Moreover, accurate singers were more consistent when tapping to the beat. These differences cannot be ascribed to basic motor skills or to motivational factors. Individual differences in terms of singing proficiency and synchronization skills may reflect the variability of a shared sensorimotor translation mechanism.

  16. Elastic Beating Pump Using Induced-Charge Electro-osmosis

    Science.gov (United States)

    Sugioka, Hideyuki

    2016-10-01

    Pumping a viscous liquid in a confined space is essential in microfluidic systems because the pressure-driven flow rate through small channels decreases with the third or fourth power of the channel size. Hence, inspired by a cilium's pumping ability in a confined space, we propose an elastic beating pump using a hydrodynamic force due to induced-charge electro-osmosis (ICEO) and numerically examine the pumping performance. By the multiphysics coupled simulation technique based on the boundary element method along with the thin double-layer approximation, we find that by selecting the optimum rigidity of the elastic beam, the ICEO elastic beating pump functions effectively at high frequencies with low applied voltages and shows a large average flow velocity with a remarkably large peak velocity that may be useful to flow a liquid with unexpectedly high viscosity. Furthermore, we propose a simple model that explains the characteristics of the time response behavior of the ICEO elastic beating pump tosome extent. By this analysis, we can considerably contribute to developments in studies on the artificial cilia having versatile functions.

  17. Worsening Hypoxemia in the Face of Increasing PEEP: A Case of Large Pulmonary Embolism in the Setting of Intracardiac Shunt

    Science.gov (United States)

    Granati, Glen T.; Teressa, Getu

    2016-01-01

    Patient: Male, 40 Final Diagnosis: Patent foramen ovale Symptoms: Dyspnea exertional • hemoptysis • shortness of breath Medication: — Clinical Procedure: Airway pressure release ventilation Specialty: Critical Care Medicine Objective: Rare co-existance of disease or pathology Background: Patent foramen ovale (PFO) are common, normally resulting in a left to right shunt or no net shunting. Pulmonary embolism (PE) can cause sustained increased pulmonary vascular resistance (PVR) and right atrial pressure. Increasing positive end-expiratory pressure (PEEP) improves oxygenation at the expense of increasing intrathoracic pressures (ITP). Airway pressure release ventilation (APRV) decreases shunt fraction, improves ventilation/perfusion (V/Q) matching, increases cardiac output, and decreases right atrial pressure by facilitating low airway pressure. Case Report: A 40-year-old man presented with dyspnea and hemoptysis. Oxygen saturation (SaO2) 80% on room air with A a gradient of 633 mmHg. Post-intubation SaO2 dropped to 71% on assist control, FiO2 100%, and PEEP of 5 cmH20. Successive PEEP dropped SaO2 to 60–70% and blood pressure plummeted. APRV was initaiated with improvement in SaO2 to 95% and improvement in blood pressure. Hemiparesis developed and CT head showed infarction. CT pulmonary angiogram found a large pulmonary embolism. Transthoracic echocardiogram detected right-to left intracardiac shunt, with large PFO. Conclusions: There should be suspicion for a PFO when severe hypoxemia paradoxically worsens in response to increasing airway pressures. Concomitant venous and arterial thromboemboli should prompt evaluation for intra cardiac shunt. Patients with PFO and hypoxemia should be evaluated for causes of sustained right-to left pressure gradient, such as PE. Management should aim to decrease PVR and optimize V/Q matching by treating the inciting incident (e.g., thrombolytics in PE) and by minimizing ITP. APRV can minimize PVR and maximize V/Q ratios and

  18. In vitro effect of biologically active coating on endothelialisation of Nitinol coils designed for the closure of intracardiac shunt

    Institute of Scientific and Technical Information of China (English)

    Xiangqing Kong

    2005-01-01

    Objective: To evaluate in vitro the effect of biologically active coating on endothelialisation of Nitinol coils designed for the closure of intracardiac shunt. Methods: Covalently binding procedure was performed with chemical vapor deposition (CVD).Heparin(200 IU/ml ), r-hirudin(21 nmol/ml ), or fibronectin( 15 μg/ml), respectively, were bound to the basic coating( poly( amino- p- xylylene-co-p-xylylen) ). In vitro tests were performed on five different coating groups( n = 2 each) : uncoated Nitinol, basic coating, heparin-,r-hirudin-,and fibronectin-coating. Human umbilical vein endothelial cells(HUVECs) were cultured in the presence of tested coils for 48 and 72 h. Adhesion of HUVECs were evaluated with light microscopy,and with confocal laser scanning microscopy after double-staining of vinculin,phalloidin, Ki67 and fibronectin. Results: After 48 and 72 h of incubation,except HUVECs around the basic coating showing abnormal morphology, HUVECs were able to grow next to all kinds of coils. By CLSM adhering cells were typically confined to maximal three secondary coil windings. HUVECs adhered best to the fibronectin coated coils,followed by the uncoated Nitinol. HUVECs barely adhered to the basic coating. The adhesion to heparin coating or r-hirudin coating was observed with various cell densities. Heparin coating seemed to support cell adhesion better than r-hirudin coating did. The HUVECs assembled fibronectin matrix on the fibronectin coating and uncoated Nitinol coil. Vinculin was expressed on both fibronectin coating and uncoated Nitinol as well, mostly diffused,but occasionally also in focal contacts. Ki67 expression was mainly noticed on the uncoated Nitinol coil and fibronectin coated coil, only occasionally on other materials. The densities and morphology of HUVECs, adhered to the correspohding well surfaces, were similar for all wells. The only exception was the well with the basic coating coil after three days of incubation. In this case, the cell

  19. ECG criteria for localizing the pulmonary vein origin of spontaneous atrial premature complexes: validation using intracardiac recordings.

    Science.gov (United States)

    Rajawat, Yadavendra S; Gerstenfeld, Edward P; Patel, Vickas V; Dixit, Sanjay; Callans, David J; Marchlinski, Francis E

    2004-02-01

    We have shown that pacemapping from each of the pulmonary veins reveals unique surface ECG characteristics. However, application of these criteria to spontaneous atrial premature complexes is often difficult because of obscuration by the prior T wave. We hypothesized that the pulmonary vein of origin of spontaneous atrial premature complexes can be determined by measuring characteristics of the P wave whether or not the P wave was superimposed on the prior T wave. We analyzed 58 spontaneous atrial premature complexes of known pulmonary vein origin in 30 patients referred for atrial fibrillation ablation. The origin of all the atrial premature complexes was documented by detailed, intracardiac multipolar catheter mapping. Based on previous work, the criteria for distinguishing right-sided from left-sided pulmonary vein origin of atrial premature complex includes: (1) P wave duration wave amplitude in lead I > 0.05 mV; and (3) P wave amplitude in leads II/III > 1.25. The criteria to separate superior from inferior pulmonary veins included the sum of the P wave amplitude in all the inferior leads greater than 0.3 mV. The combination of the P wave duration wave amplitude in leads II/III > 1.25, distinguished right-sided from left-sided pulmonary vein origin of spontaneous atrial premature complexes with a sensitivity of 82% and specificity of 100%. The sum of the P wave amplitude in leads II, III, and aVF > 0.3 mV distinguished superior from inferior pulmonary vein of origin with a sensitivity of 39% and specificity of 73%. The pulmonary vein origin of spontaneous atrial premature complexes can often be localized using careful quantitative analysis of the surface ECG despite superimposition of the P wave upon the T wave. Separation of right-sided from left-sided pulmonary vein origin of spontaneous atrial premature complexes can be determined with good specificity and sensitivity, while the ability to distinguish inferior from superior pulmonary vein origin is limited.

  20. Congenital heart block with hydrops fetalis treated with high-dose dexamethasone; a case report.

    Science.gov (United States)

    Chua, S; Ostman-Smith, I; Sellers, S; Redman, C W

    1991-11-26

    A 32-year-old woman with systemic lupus erythematosus was found to have a fetus with heart block and fetal ascites at 23 weeks gestation. Treatment with high-dose corticosteroids ameliorated the early signs of heart failure, although the fetal heart rate gradually fell from 48 beats/min to 42 beats/min by 34 weeks. Sudden deterioration of the fetal state occurred at 35 weeks, and this only partially responded to digitalisation. Neonatal death occurred on Day 18 from the consequences of severe birth asphyxia. The relationship and pathogenesis of anti-Ro antibodies, congenital heart block and hydrops fetals are discussed, together with the in utero management of this condition. PMID:1765211

  1. Mitochondria and heart failure: new insights into an energetic problem

    OpenAIRE

    Chen, L.; Knowlton, A. A.

    2010-01-01

    Cardiac mitochondria are powerful organelles supplying energy to support the high adenosine triphosphate (ATP) consumption of the beating heart. The progression of HF (HF) is characterized by diminished energy metabolism, calcium mishandling, reactive oxygen species (ROS) generation and apoptotic cell death. Although the etiologies of HF are multifactoral, many of the changes of HF are associated with cardiac mitochondrial dysfunction either directly or indirectly. A number of studies have es...

  2. Heart Disease

    Science.gov (United States)

    ... Added Sugar Intake and Cardiovascular Diseases Mortality Among US Adults, examines the relationship between consuming too much added sugar and the risk of heart disease death. When it Comes to Blood Pressure, Make Control ...

  3. Heart Failure

    Science.gov (United States)

    ... together. About Rise Above HF Rise Above Heart Failure seeks to increase the dialogue about HF and improve the lives of people affected by the condition through awareness, education and support. Through the initiative, AHA strives to ...

  4. Aortic arch replacement with a beating heart: a simple method using continuous 3-way perfusion.

    Science.gov (United States)

    Abu-Omar, Y; Ali, J M; Colah, S; Dunning, J J

    2014-01-01

    We describe a simplified 3-way perfusion strategy that could be used in complex aortic procedures, which ensures continuous end-organ perfusion and minimizes the potential risks of cardiac, cerebral and peripheral ischaemic complications.

  5. Surgical revascularization on the beating heart in patients with low ejection fraction

    OpenAIRE

    Putnik Svetozar; Velinović Miloš; Mikić Aleksandar; Vraneš Mile; Nikolić Bojan; Krstić Nevena; Ristić Miljko

    2011-01-01

    Introduction. The subset of patients most likely to benefit from off-pump coronary artery bypass grafting (OPCABG) remains a controversial issue, but the technique has been proposed to decrease postoperative mortality and morbidity. Coronary artery bypass grafting (CABG) with a cardiopulmonary bypass carries a significant risk for patients with severe left ventricular (LV) dysfunction. Objective. The objective of this study was to compare off-pump to on-pump CABG in patients with ejecti...

  6. The Beat of the Economic Heart: Joseph Schumpeter and Arthur Spiethoff on Business Cycles

    OpenAIRE

    Kurz, Heinz D.

    2010-01-01

    The paper discusses the relationship between Arthur Spiethoff and Joseph A. Schumpeter, the men and their works. Had it not been for Spiethoff Schumpeter would in all probability have forever been lost to scientific work. It was Spiethoff who brought the Austrian back to academia and research after a sequence of serious mishaps in politics and banking. Spiethoff's contribution to an analysis of business cycles is then summarized and important similarities and some differences between it and S...

  7. Heart Beat Detection in Noisy ECG Signals Using Statistical Analysis of the Automatically Detected Annotations

    Directory of Open Access Journals (Sweden)

    Andrius Gudiškis

    2015-07-01

    Full Text Available This paper proposes an algorithm to reduce the noise distortion influence in heartbeat annotation detection in electrocardiogram (ECG signals. Boundary estimation module is based on energy detector. Heartbeat detection is usually performed by QRS detectors that are able to find QRS regions in a ECG signal that are a direct representation of a heartbeat. However, QRS performs as intended only in cases where ECG signals have high signal to noise ratio, when there are more noticeable signal distortion detectors accuracy decreases. Proposed algorithm uses additional data, taken from arterial blood pressure signal which was recorded in parallel to ECG signal, and uses it to support the QRS detection process in distorted signal areas. Proposed algorithm performs as well as classical QRS detectors in cases where signal to noise ratio is high, compared to the heartbeat annotations provided by experts. In signals with considerably lower signal to noise ratio proposed algorithm improved the detection accuracy to up to 6%.

  8. "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…

  9. Heart Beat Detection in Noisy ECG Signals Using Statistical Analysis of the Automatically Detected Annotations

    OpenAIRE

    Andrius Gudiškis

    2015-01-01

    This paper proposes an algorithm to reduce the noise distortion influence in heartbeat annotation detection in electrocardiogram (ECG) signals. Boundary estimation module is based on energy detector. Heartbeat detection is usually performed by QRS detectors that are able to find QRS regions in a ECG signal that are a direct representation of a heartbeat. However, QRS performs as intended only in cases where ECG signals have high signal to noise ratio, when there are more noticeable signal dis...

  10. Comparison of hemodynamic responses to dexmedetomidine versus esmolol in patients undergoing beating heart surgery

    OpenAIRE

    Mohamed Abdel Rahman Salem M.D,* Mostafa Elhamamsy M.D

    2001-01-01

    adrenergic agonists decrease sympathetic tone with ensuing attenuation of neuroendocrine and hemodynamic responses to anesthesia and surgery. Also, administration of beta -adrenergic antagonists contributes to prophylaxis against hypertension, tachycardia and myocardial ischemia and myocardial protection during cardiac surgery. The effects of dexmedetomidine (DEX), a highly specific alpha -adrenergic agonist, on these responses have not yet been fully reported in patients undergoing cardiac s...

  11. Coronary heart disease

    Science.gov (United States)

    Heart disease, Coronary heart disease, Coronary artery disease; Arteriosclerotic heart disease; CHD; CAD ... Coronary heart disease is the leading cause of death in the United States for men and women. Coronary heart ...

  12. Episodic arterial oxygen desaturation and heart rate variations following major abdominal surgery

    DEFF Research Database (Denmark)

    Rosenberg, J; Dirkes, W E; Kehlet, H

    1989-01-01

    In 20 patients undergoing elective major abdominal surgery, heart rate and arterial oxygen saturation were monitored continuously during the night 2 days before operation and during the first and second nights after operation (23:00 to 07:30). Mean heart rate increased by 16 beat min-1 (P less than...... arrhythmias on the morning of the third day after operation. In another patient the episodes of desaturation correlated with increases in heart rate. There was no correlation between administration of opioids and heart rate and saturation disturbances. The mechanism and clinical relevance of episodic...

  13. Estimation of radiation dose and image quality of coronary 320-row area detector CT angiography by optimal prospective ECG-gated protocols for different heart rate

    International Nuclear Information System (INIS)

    The purpose of this study is to estimate radiation dose and image quality of electrocardiogram (ECG)-gated coronary 320-area detector CT (ADCT) angiography which was acquired using the protocols that were considered as optimal methods for different heart rates (HR) in 1031 consecutive patients (M/F =580/451, 65±12 yr) without arrhythmias. We set up 5 protocols for 320-ADCT based on the relationship among heart rates, temporal resolution, gantry rotation speed, optimal reconstruction phase and slow filling phase on 64-multidetector-row computed tomography (MDCT), id est (ie), 1) mid-diastolic (75% of risk ratio (RR)) 1 beat scan (moderate disability (MD) 1 beat, N=761 (73.8%)) for HR ≤60, 2) mid-diastolic (75% of RR) 2 beat scan (MD 2 beat, N=135) for 61≤ HR ≤65, 3) end-systolic and mid-diastolic (37-80% of RR) 2 beat scan (embryonic stem (ES)-MD 2 beat, N=92) for 66≤ HR ≤75, 4) end-systolic (R +280-430 ms) 2 beat scan (ES 2 beat, N=21) for 76≤ HR ≤80, and 5) end-systolic (R +250-400 ms) 3 beat scan (ES 3 beat, N=22) for 81≤ HR ≤105. Image quality was classified into 3 categories (excellent (3 points), acceptable (2 points), and unacceptable (1 point)). Scanning time, DLP.e and image quality score were 1.4±0.1 s, 220±59 mGy·cm, 3.0±0.2 points in MD 1 beat, 2.2±0.2 s, 434±118 mGy·cm, 2.9±0.3 points in MD 2 beat, 2.1±0.2 s, 729±229 mGy·cm, 2.7±0.5 points in ES-MD 2 beat, 1.9±0.1 s, 432±148 mGy·cm, 2.2±0.6 points in ES 2 beat, and 2.4±0.2 s, 669±152 mGy·cm, 2.3±0.6 points in ES 3 beat respectively. In conclusion, the prospective ECG-gated scan protocol for coronary 320-ADCT angiography in any HR group was considered reasonable and proper for image quality and radiation dose. (author)

  14. Heart failure

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    2008037 Factors associated with efficacy of cardiac resynchronization therapy for patients with congestive heart failure. SHI Haoying(史浩颖), et al. Dept Cardiol, Zhongshan Hosp Fudan Univ, Shanghai 200032. Chin J Cardiol 2007;35(12):1099-1163. Objective The efficacy of cardiac resynchronization therapy (CRT) in patients with congestive heart failure and the potential factors associated with responder or nonresponder were investigated. Methods Fifty

  15. Influence of 50 Hz magnetic field on human heart rate variability: linear and nonlinear analysis.

    Science.gov (United States)

    Tabor, Zbisław; Michalski, Józef; Rokita, Eugeniusz

    2004-09-01

    This study investigated the problem of the influence of 50 Hz magnetic field (MF) on human heart rate variability (HRV). The exposure system was a commercial device for magnetotherapy, generating field of the strength of 500 microT at the center of the coil, 150-200 microT at the position of human subjects' heart and 20-30 microT at the position of subjects' head. The exposure protocols, applied randomly, were either "half hour MF-off/half hour MF-on" or "half hour MF-off/half hour MF-off." The phonocardiographic (PhCG) signal of 15 volunteers were obtained during exposure and used for calculation of time-domain HRV parameters (mean time between heart beats (N-N), standard deviation of time between heart beats (SDNN), and the number of differences of successive beat-to-beat intervals greater than 50 ms, divided by the total number of beat-to-beat intervals (pNN50)) and nonlinear HRV measures (approximate entropy (ApEn), detrended fluctuation scaling exponents). The protocol MF-off/MF-on was applied in nine subjects. Repeated measures ANOVA (RMANOVA) performed for Mf-off/MF-off protocol indicated no statistical difference among four 15 min intervals of HRV data (P value >20% for all parameters except for N-N, where P = 3.7%). RMANOVA followed by the post hoc Tukey test performed for Mf-off/MF-on protocol indicated a statistically significant difference during MF on for N-N (8% increase, P <.1%), SDNN (40% increase, P = 1.1%), and pNN50 (110% increase, P <.1%). The results of the analysis indicate that the changes of these parameters could be associated with the influence of MF. PMID:15300734

  16. Analysis of Heart Rate and Heart Rate Variation During Cardiac CT Examinations

    Science.gov (United States)

    Zhang, Jie; Fletcher, Joel G.; Harmsen, W. Scott; Araoz, Philip A.; Williamson, Eric E.; Primak, Andrew N.; McCollough, Cynthia H.

    2009-01-01

    Rationale and Objectives We sought to examine heart rate and heart rate variability during cardiac computed tomography (CT). Materials and Methods Ninety patients (59.0 ± 13.5 years) underwent coronary CT angiography (CTA), with 52 patients also undergoing coronary artery calcium scanning (CAC). Forty-two patients with heart rate greater than 70 bpm were pretreated with oral β-blockers (in five patients, use of β-blocker was not known). Sixty-four patients were given sublingual nitroglycerin. Mean heart rate and percentage of beats outside a ±5 bpm region about the mean were compared between baseline (free breathing), prescan hyperventilation, and scan acquisition (breath-hold). Results Mean scan acquisition time was 13.1 ± 1.5 seconds for CAC scanning and 14.2 ± 2.9 seconds for coronary CTA. Mean heart rate during scan acquisition was significantly lower than at baseline (CAC 58.2 ± 8.5 bpm; CTA 59.2 ± 8.8 bpm; baseline 62.8 ± 8.9 bpm; P .05). Conclusions Breath-holding during cardiac CT scan acquisition significantly lowers the mean heart rate by approximately 4 bpm, but heart rate variability is the same or less compared with normal breathing. PMID:18078905

  17. ECG signal analysis for detection of Heart Rate and Ischemic Episodes

    OpenAIRE

    Goutam Kumar Sahoo, Samit Ari, Sarat Kumar Patra

    2013-01-01

    Electrocardiogram (ECG) is generally used fordiagnosis ofcardiovascularabnormalitiesanddisorders.Anefficient method for analysingtheECG signal towards the detection ofheartrate(HR)andischemic episodesfollows mainly fivestages:pre-processing, feature extraction,heart ratedetection,beat classification and ischemicepisoderecognition.Theheart rate is calculatedusing theextracted featuresoftheECG signal. Thecalculated HRvaluecan beanalysedforthedetectionofvariouscardiovascularabnormalities.Theabil...

  18. Cine magnetic resonance imaging in congenital heart disease

    International Nuclear Information System (INIS)

    Cine magnetic resonance imaging (MRI) was performed in 33 patients aged 19 days to 18 years (mean 5.1 years), who had congenital heart disease comfirmed at echocardiography or angiography. Prior to cine MRI, gated MRI with spin echo (SE) sequence was perfomed to evaluate cardiac structure. Cine MRI was demonstrated by fast low fip angle shot imaging technique with a 30 deg flip angle, 15 msec echo time, 30∼40 msec pulse repetition time, and 128X128 acquisition matrix. Abnormalities of cardiac structure were extremely well defined in all patients. Intracardiac and intravasucular blood flow were visualized with high signal intensity area, whereas ventricular filling flow and left to right shunt flow through ventricular septal defect and atrial septal defect were visualized with low signal intensity area. However, in the patients who had severe congestive heart failure or respiratory arrhythmia, the good recording of cine MRI was not obtained because of artifacts. Gated MRI with SE sequence provides excellent visualization of fine structures, and cine MRI can provide high spatial resolution imaging of flow dynamic in a variety of congenital heart disease, noninvasively. (author)

  19. Intracardiac tumor causing

    Directory of Open Access Journals (Sweden)

    Christopher P. Jordan

    2016-07-01

    Full Text Available The following report describes the case of newborn girl with an asymptomatic systolic murmur, which on imaging revealed a nearly obstructive mass in the left-ventricular outflow tract. The mass was resected and found to be consistent with a rhabdomyoma. Here, we describe the pathologic and clinical characteristics of this tumor.

  20. Heart rate recovery in patients with obstructive sleep apnea syndrome

    OpenAIRE

    Karaşen, Rıza Murat; ÇİFTÇİ, Bülent; Acar, Baran; YALÇIN, Ahmet Arif; GÜVEN, Selma FIRAT

    2012-01-01

    To demonstrate the effects of obstructive sleep apnea syndrome (OSAS) on baroregulatory function by using heart rate recovery (HRR) parameters. Materials and methods: Fifty-four moderate and severe OSAS patients were included in the study. HRR was defined as the difference in heart rate between peak exercise and 1 min later; a value of 18 beats/min was considered abnormal. OSAS patients were enrolled in the study as group 1 (normal HRR; n = 12) and group 2 (abnormal HRR, n = 42). Left ventr...

  1. Dynamic curvature regulation accounts for the symmetric and asymmetric beats of Chlamydomonas flagella

    CERN Document Server

    Sartori, Pablo; Scholich, Andre; Jülicher, Frank; Howard, Jonathon

    2015-01-01

    Axonemal dyneins are the molecular motors responsible for the beating of cilia and flagella. These motors generate sliding forces between adjacent microtubule doublets within the axoneme, the motile cytoskeletal structure inside the flagellum. To create regular, oscillatory beating patterns, the activities of the axonemal dyneins must be coordinated both spatially and temporally. It is thought that coordination is mediated by stresses or strains that build up within the moving axoneme, but it is not known which components of stress or strain are involved, nor how they feed back on the dyneins. To answer this question, we used isolated, reactivate axonemes of the unicellular alga Chlamydomonas as a model system. We derived a theory for beat regulation in a two-dimensional model of the axoneme. We then tested the theory by measuring the beat waveforms of wild type axonemes, which have asymmetric beats, and mutant axonemes, in which the beat is nearly symmetric, using high-precision spatial and temporal imaging....

  2. Decrease of cardiac chaos in congestive heart failure

    Science.gov (United States)

    Poon, Chi-Sang; Merrill, Christopher K.

    1997-10-01

    The electrical properties of the mammalian heart undergo many complex transitions in normal and diseased states. It has been proposed that the normal heartbeat may display complex nonlinear dynamics, including deterministic chaos,, and that such cardiac chaos may be a useful physiological marker for the diagnosis and management, of certain heart trouble. However, it is not clear whether the heartbeat series of healthy and diseased hearts are chaotic or stochastic, or whether cardiac chaos represents normal or abnormal behaviour. Here we have used a highly sensitive technique, which is robust to random noise, to detect chaos. We analysed the electrocardiograms from a group of healthy subjects and those with severe congestive heart failure (CHF), a clinical condition associated with a high risk of sudden death. The short-term variations of beat-to-beat interval exhibited strongly and consistently chaotic behaviour in all healthy subjects, but were frequently interrupted by periods of seemingly non-chaotic fluctuations in patients with CHF. Chaotic dynamics in the CHF data, even when discernible, exhibited a high degree of random variability over time, suggesting a weaker form of chaos. These findings suggest that cardiac chaos is prevalent in healthy heart, and a decrease in such chaos may be indicative of CHF.

  3. AUTONOMIC CONTROL OF HEART RATE AFTER EXERCISE IN TRAINED WRESTLERS

    Science.gov (United States)

    Báez, San Martín E.; Von Oetinger, A.; Cañas, Jamett R.; Ramírez, Campillo R.

    2013-01-01

    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. PMID:24744476

  4. Heart Rate Variability Measures and Models

    CERN Document Server

    Teich, M C; Jost, B M; Vibe-Rheymer, K; Heneghan, C; Teich, Malvin C.; Lowen, Steven B.; Jost, Bradley M.; Vibe-Rheymer, Karin; Heneghan, Conor

    2001-01-01

    We focus on various measures of the fluctuations of the sequence of intervals between beats of the human heart, and how such fluctuations can be used to assess the presence or likelihood of cardiovascular disease. We examine sixteen such measures and their suitability for correctly classifying heartbeat records of various lengths as normal or revealing the presence of cardiac dysfunction, particularly congestive heart failure. Using receiver-operating-characteristic analysis we demonstrate that scale-dependent measures prove substantially superior to scale-independent ones. The wavelet-transform standard deviation at a scale near 32 heartbeat intervals, and its spectral counterpart near 1/32 cycles/interval, turn out to provide reliable results using heartbeat records just minutes long. We further establish for all subjects that the human heartbeat has an underlying stochastic origin rather than arising from a chaotic attractor. Finally, we develop a mathematical point process that emulates the human heartbea...

  5. On-Pump Beating Coronary Artery Bypass in High Risk Coronary Patients

    Directory of Open Access Journals (Sweden)

    Abbas Afrasiabirad

    2015-01-01

    Full Text Available Background: There are some conflicting results with Conventional Coronary Artery Bypass Grafts (CCABG with arrested heart in coronary high-risk patients. Moreover, performing off-pump CABG in these cases may be associated with serious complications. The objective of this study is to evaluate the efficacy of the on-pump beating CABG (OPBCABG in coronary high-risk patients in comparison with the conventional methods. Methods: In a prospective research study, 3000 off-pump CABG patients were considered during June 2003 to December 2011. Among these, 157 patients with one or more of the following risk factors were included for OPBCABG; severe left main stenosis, early post-acute myocardial infarction with ongoing chest pain, unstable angina, intractable ventricular arrhythmia, post complicated coronary intervention and severe left ventricular dysfunction. These patients were compared with 157 similar patients undergone CCABG with aortic cross clamp before 2003. Results: Preoperative patient characteristics revealed no significant differences between the two groups. The patients’ mean age and number of grafts were 57 years and 3 per patient respectively. Hospital mortality was 3.2% and 9% in OPBCABG and CCABG groups, respectively (P<0.001. Preoperative myocardial infarction, requirement of inotropic agents and intraaortic balloon pump, renal dysfunction and prolonged ventilation time were significantly higher in CCABG group. Conclusion: Our results suggest that OPBCABG is effective in coronary high-risk patients and significantly reduces mortality and the incidence of perioperative MI and other major complications.

  6. Individual differences in beat perception affect gait responses to low- and high-groove music.

    Science.gov (United States)

    Leow, Li-Ann; Parrott, Taylor; Grahn, Jessica A

    2014-01-01

    Slowed gait in patients with Parkinson's disease (PD) 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 patients with PD 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 to 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. PMID:25374521

  7. Matrix Organisation : The design of cross-beat teamwork in newsrooms

    OpenAIRE

    Grubenmann, Stephanie

    2016-01-01

    Confronted by increased internal and external complexity, traditional forms of newswork have reached their limits. Journalistic start-ups, such as Quartz and NZZ.at, form emerging editorial teams around "obsessions" or "phenomena" to gain cross-beat perspectives of complex issues such as climate change, the financial crisis or the refugee crisis. Legacy media experimenting with cross-beat newswork see themselves confronted by challenges arising predominantly from beat structures. Consequently...

  8. 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.

  9. Can compressed sensing beat the Nyquist sampling rate?

    CERN Document Server

    Yaroslavsky, L

    2015-01-01

    Data saving capability of "Compressed sensing (sampling)" in signal discretization is disputed and found to be far below the theoretical upper bound defined by the signal sparsity. On a simple and intuitive example, it is demonstrated that, in a realistic scenario for signals that are believed to be sparse, one can achieve a substantially larger saving than compressing sensing can. It is also shown that frequent assertions in the literature that "Compressed sensing" can beat the Nyquist sampling approach are misleading substitution of terms and are rooted in misinterpretation of the sampling theory.

  10. Different Rebellions--The and the Angry Beat Generation Man

    Institute of Scientific and Technical Information of China (English)

    欧国芳

    2012-01-01

    The Beat Generation (BG) and the Angry Man (AYM) both emerged after the Second World War. Thus, the misunderstanding of the two has existed for a long time. Large quantities of people called the BG the American Angry Young Man. Undoubtedly, the two resembled each other to some extent. However, the BG and the AYM can't be treated alike, for their differences far outweighed their similarities. This paper aims to analyze their differences in many aspects like the national environment and their memberships, which consequently led to other differences such as the differences in essences, features, influence and finale.

  11. 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.

  12. Nonlinear and stochastic dynamics in the heart

    International Nuclear Information System (INIS)

    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

  13. 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.

  14. The role of stents in the treatment of congenital heart disease: Current status and future perspectives

    International Nuclear Information System (INIS)

    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

  15. Enhanced timing abilities in percussionists generalize to rhythms without a musical beat

    Science.gov (United States)

    Cameron, Daniel J.; Grahn, Jessica A.

    2014-01-01

    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 meters 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. PMID:25540617

  16. 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.

  17. Heart failure

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    2009170 Curcumin attenuates left ventricular dysfunction and remodeling in rabbits with chronic heart failure. TANG Yanhong(唐艳红),et al.Dept Cardiol,Renmin Hosp,Wuhan Univ,Wuhan 430060.Chin J Cardiol,2009;37(3):262-267.

  18. Heart Health - Heart Disease: Symptoms, Diagnosis, Treatment

    Science.gov (United States)

    ... Bar Home Current Issue Past Issues Cover Story Heart Health Heart Disease: Symptoms, Diagnosis, Treatment Past Issues / Winter 2009 ... of this page please turn Javascript on. Most heart attacks happen when a clot in the coronary ...

  19. Heart Health: The Heart Truth Campaign 2009

    Science.gov (United States)

    ... Bar Home Current Issue Past Issues Cover Story Heart Health The Heart Truth Campaign 2009 Past Issues / Winter 2009 Table ... one of the celebrities supporting this year's The Heart Truth campaign. Both R&B singer Ashanti (center) ...

  20. QRS template matching for recognition of ventricular ectopic beats.

    Science.gov (United States)

    Krasteva, Vessela; Jekova, Irena

    2007-12-01

    We propose a quasi real-time method for discrimination of ventricular ectopic beats from both supraventricular and paced beats in the electrocardiogram (ECG). The heartbeat waveforms were evaluated within a fixed-length window around the fiducial points (100 ms before, 450 ms after). Our algorithm was designed to operate with minimal expert intervention and we define that the operator is required only to initially select up to three 'normal' heartbeats (the most frequently seen supraventricular or paced complexes). These were named original QRS templates and their copies were substituted continuously throughout the ECG analysis to capture slight variations in the heartbeat waveforms of the patient's sustained rhythm. The method is based on matching of the evaluated heartbeat with the QRS templates by a complex set of ECG descriptors, including maximal cross-correlation, area difference and frequency spectrum difference. Temporal features were added by analyzing the R-R intervals. The classification criteria were trained by statistical assessment of the ECG descriptors calculated for all heartbeats in MIT-BIH Supraventricular Arrhythmia Database. The performance of the classifiers was tested on the independent MIT-BIH Arrhythmia Database. The achieved unbiased accuracy is represented by sensitivity of 98.4% and specificity of 98.86%, both being competitive to other published studies. The provided computationally efficient techniques enable the fast post-recording analysis of lengthy Holter-monitor ECG recordings, as well as they can serve as a quasi real-time detection method embedded into surface ECG monitors. PMID:17805974

  1. Unraveling the nature of coherent beatings in chlorosomes

    Energy Technology Data Exchange (ETDEWEB)

    Dostál, Jakub [Department of Chemical Physics, Lund University, P.O. Box 124, SE-22100 Lund (Sweden); Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 121 16 Prague (Czech Republic); Mančal, Tomáš; Pšenčík, Jakub [Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 121 16 Prague (Czech Republic); Vácha, František [Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice (Czech Republic); Zigmantas, Donatas, E-mail: donatas.zigmantas@chemphys.lu.se [Department of Chemical Physics, Lund University, P.O. Box 124, SE-22100 Lund (Sweden)

    2014-03-21

    Coherent two-dimensional (2D) spectroscopy at 80 K was used to study chlorosomes isolated from green sulfur bacterium Chlorobaculum tepidum. Two distinct processes in the evolution of the 2D spectrum are observed. The first being exciton diffusion, seen in the change of the spectral shape occurring on a 100-fs timescale, and the second being vibrational coherences, realized through coherent beatings with frequencies of 91 and 145 cm{sup −1} that are dephased during the first 1.2 ps. The distribution of the oscillation amplitude in the 2D spectra is independent of the evolution of the 2D spectral shape. This implies that the diffusion energy transfer process does not transfer coherences within the chlorosome. Remarkably, the oscillatory pattern observed in the negative regions of the 2D spectrum (dominated by the excited state absorption) is a mirror image of the oscillations found in the positive part (originating from the stimulated emission and ground state bleach). This observation is surprising since it is expected that coherences in the electronic ground and excited states are generated with the same probability and the latter dephase faster in the presence of fast diffusion. Moreover, the relative amplitude of coherent beatings is rather high compared to non-oscillatory signal despite the reported low values of the Huang-Rhys factors. The origin of these effects is discussed in terms of the vibronic and Herzberg-Teller couplings.

  2. Robust estimation of the motile cilia beating frequency.

    Science.gov (United States)

    Meste, O; Brau, F; Guyon, A

    2015-10-01

    The estimation of the cilia beating frequency (CBF) is of great interest in understanding how the CBF modulates liquid fluxes and how it is controlled by the ciliated cell intra- and/or extracellular medium composition in physiological processes. Motion artifacts and camera defaults may hinder the computation of the frequency variations during long-lasting experiments. We have developed a new analysis approach consisting of a preliminary corrective step (removal of a grid pattern on the image sequence and shift compensation), followed by a harmonic model of the observed cilia using a maximum likelihood estimator framework. It is shown that a more accurate estimation of the frequency can be obtained by averaging the squared Fourier transform of individual pixels followed by a particular summation over the different frequencies, namely the compressed spectrum. Robustness of the proposed method over traditional approaches is shown by several examples and simulations. The method is then applied to images of samples containing ciliated ependymal cells located in the third cerebral ventricle of mouse brains, showing that even small variations in CBF in response to changes in the amount of oxygenation, pH or glucose were clearly visible in the computed frequencies. As a conclusion, this method reveals a fine metabolic tuning of the cilia beating in ependimocytes lining the third cerebral ventricle. Such regulations are likely to participate in homeostatic mechanisms regulating CSF movements and brain energy supply. PMID:26215519

  3. Heart disease - resources

    Science.gov (United States)

    Resources - heart disease ... The following organizations are good resources for information on heart disease: American Heart Association -- www.heart.org Centers for Disease Control and Prevention -- www.cdc.gov/heartdisease

  4. Heart Diseases and Disorders

    Science.gov (United States)

    ... Resources Heart Diseases & Disorders Back to Patient Resources Heart Diseases & Disorders Millions of people experience irregular heartbeats, called ... harmless and happen in healthy people free of heart disease. However, some abnormal heart rhythms can be serious ...

  5. Heart disease and diet

    Science.gov (United States)

    Diet - heart disease ... diet and lifestyle can reduce your risk of: Heart disease, heart attacks, and stroke Conditions that lead to heart disease, including high cholesterol , high blood pressure, and obesity ...

  6. Heart Attack Risk Assessment

    Science.gov (United States)

    ... Pressure Tools & Resources Stroke More Heart Attack Risk Assessment Updated:May 31,2016 We're sorry, but ... Can You Recognize a Heart Attack? Quiz Risk Assessment Patient Information Sheets: Heart Attack Heart Attack Personal ...

  7. Heart pacemaker - discharge

    Science.gov (United States)

    ... Elsevier Saunders; 2014:chap 36. Read More Arrhythmias Atrial fibrillation or flutter Cardiac ablation procedures Coronary heart disease Heart bypass surgery Heart bypass surgery - minimally invasive Heart failure - overview High blood cholesterol levels Sick sinus syndrome ...

  8. Heart and Stroke Encyclopedia

    Science.gov (United States)

    ... Y Z What's Your Risk? Heart Attack Risk Assessment Determine your risk of having a heart attack or dying from coronary heart disease and get a report to discuss with your healthcare provider. Determine your risk of having a heart ...

  9. Heart attack first aid

    Science.gov (United States)

    First aid - heart attack; First aid - cardiopulmonary arrest; First aid - cardiac arrest ... A heart attack occurs when the blood flow that carries oxygen to the heart is blocked. The heart muscle ...

  10. What Causes Heart Block?

    Science.gov (United States)

    ... or inflammation of the heart muscle. Heart failure . Rheumatic (roo-MAT-ik) fever. Cardiomyopathy (KAR-de-o-mi-OP-a-the), or heart muscle diseases. Other diseases may increase the risk of heart ...

  11. Comparative study on cerebral injury after open heart surgery in patients with congenital and rheumatic heart disease

    Institute of Scientific and Technical Information of China (English)

    WANG Yong; XIAO Ying-bin; CHEN Lin; ZHONG Qian-jin; WANG Xue-feng

    2005-01-01

    Objective: To comparatively study the different effects of open heart surgery on brain tissues of patients with congenital and rheumatic heart disease. Methods: Forty patients with congenital heart disease (CHD, CHD group, n=20) or rheumatic heart disease (RHD, RHD group, n=20) underwent on-pump (cardiopulmonary bypass, CPB) heart-beating open heart surgery. Blood samples before CPB, and 20 minutes, 1 hour, 24 hours and 7 days after CPB were collected, and the levels of neuron-specific enolase (NSE) and protein S-100b in the plasma were determined with enzyme-linked immunoadsorbent assay (ELISA), respectively. All the patients were examined with electroencephalogram (EEG) before and 1 week after operation. The changes of NSE, S-100b and EEG compared to verify the difference of postoperative cerebral injury between CHD cases and RHD cases. Results: The plasma level of S-100b increased significantly 20 minutes after CPB and was still higher than the preoperative level at 24 hours after operation in both groups (P<0.01). The plasma level of NSE increased more significantly in the CHD group than in the RHD group 20 minutes after CPB and it returned to the normal level 24 hours after CPB in the CHD group but remained at a high level in the RHD group (P<0.01). The levels of NSE and S-100b returned to the normal levels on the 7th day after CPB. Abnormal EEG was found in 75% of the patients in the CHD group and 60% in the RHD group. Conclusions: On-pump heart-beating open heart surgery can cause certain cerebral injury in the patients with CHD or RHD. The injury was more severe and recovered more quickly in the CHD group than in the RHD group.

  12. Interacting cortical and basal ganglia networks underlying finding and tapping to the musical beat.

    Science.gov (United States)

    Kung, Shu-Jen; Chen, Joyce L; Zatorre, Robert J; Penhune, Virginia B

    2013-03-01

    Humans are able to find and tap to the beat of musical rhythms varying in complexity from children's songs to modern jazz. Musical beat has no one-to-one relationship with auditory features-it is an abstract perceptual representation that emerges from the interaction between sensory cues and higher-level cognitive organization. Previous investigations have examined the neural basis of beat processing but have not tested the core phenomenon of finding and tapping to the musical beat. To test this, we used fMRI and had musicians find and tap to the beat of rhythms that varied from metrically simple to metrically complex-thus from a strong to a weak beat. Unlike most previous studies, we measured beat tapping performance during scanning and controlled for possible effects of scanner noise on beat perception. Results showed that beat finding and tapping recruited largely overlapping brain regions, including the superior temporal gyrus (STG), premotor cortex, and ventrolateral PFC (VLPFC). Beat tapping activity in STG and VLPFC was correlated with both perception and performance, suggesting that they are important for retrieving, selecting, and maintaining the musical beat. In contrast BG activity was similar in all conditions and was not correlated with either perception or production, suggesting that it may be involved in detecting auditory temporal regularity or in associating auditory stimuli with a motor response. Importantly, functional connectivity analyses showed that these systems interact, indicating that more basic sensorimotor mechanisms instantiated in the BG work in tandem with higher-order cognitive mechanisms in PFC.

  13. The role of the basal ganglia in beat perception: neuroimaging and neuropsychological investigations.

    Science.gov (United States)

    Grahn, Jessica A

    2009-07-01

    Perception of musical rhythms is culturally universal. Despite this special status, relatively little is known about the neurobiology of rhythm perception, particularly with respect to beat processing. Findings are presented here from a series of studies that have specifically examined the neural basis of beat perception, using functional magnetic resonance imaging (fMRI) and studying patients with Parkinson's disease. fMRI data indicate that novel beat-based sequences robustly activate the basal ganglia when compared to irregular, nonbeat sequences. Furthermore, although most healthy participants find it much easier to discriminate changes in beat-based sequences compared to irregular sequences, Parkinson's disease patients fail to show the same degree of benefit. Taken together, these data suggest that the basal ganglia are performing a crucial function in beat processing. The results of an additional fMRI study indicate that the role of the basal ganglia is strongly linked to internal generation of the beat. Basal ganglia activity is greater when participants listen to rhythms in which internal generation of the beat is required, as opposed to rhythms with strongly externally cued beats. Functional connectivity between part of the basal ganglia (the putamen) and cortical motor areas (premotor and supplementary motor areas) is also higher during perception of beat rhythms compared to nonbeat rhythms. Increased connectivity between cortical motor and auditory areas is found in those with musical training. The findings from these converging methods strongly implicate the basal ganglia in processing a regular beat, particularly when internal generation of the beat is required. PMID:19673753

  14. Study of intracardiac flow patterns of left ventricle in patients with premature ventricular complexes from the right ventricular outflow tract%右心室流出道起源室性期前收缩患者左心室腔流场分布模式的研究

    Institute of Scientific and Technical Information of China (English)

    姚静; 许迪; 李相权; 吴红平; 雍永宏; 季玲; 陈莉

    2011-01-01

    Objective To evaluate the patterns of intracardiac flow of left ventricle (LV) in patients with premature ventricular complexes (PVCs) from the right ventricular outflow tract (RVOT) by analyzing the vortex during isovolumetric contraction phase and the distribution rules of flow-time curves in each layer of LV.Methods Twenty-seven patients with frequent isolated PVCs from RVOT were involved and 25 healthy subjects as control.The color Doppler image of LV at apical four-chamber view was acquired.Vector flow mapping (VFM) was performed to assess the parameters of vortex during isovolumic contraction phase, including diameter (transverse and vertical diameter), velocity (maximal positive and negative velocity) and the number of vortex rings.Positive flow during systole and negative flow during diastole of LV in each layer were measured by flow-time curve.All values of patients with PVCs were recorded during sinus beats (PVC-S) and PVC (PVC-V) respectively.Results Significant differences were demonstrated in all parameters of vortex between the PVC-V and control subjects.And the flow-time curves disarrayed in PVC-V.The velocity of vortex in PVC-S was lower than that in control subjects.And the distribution pattern of flow-time curves in LV of PVC-S differed from that of control subjects.Conclusions Alternation of intracardiac fluid pattern in LV was demonstrated in patients with PVCs from RVOT during both sinus beats and PVC.VFM can be used to analyze the intracardiac flow field in normal and pathological electrical activation.%目的 分析正常人及右室流出道(right ventricular outflow tract,RVOT)起源室性期前收缩(premature ventricular complexes,PVCs)患者左心室腔等容收缩期涡流及左心室腔不同层面时间-血流曲线分布规律,探讨RVOT起源PVCs对左心室腔流场分布模式的影响。方法 分别获取27例RVOT起源PVCs患者在窦性心搏、室性期前收缩时及25例正常人的心尖四腔观二维彩色多普勒

  15. 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

  16. 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.

  17. Heart wall motion analysis by dynamic 3D strain rate imaging from tissue Doppler echocardiography

    Science.gov (United States)

    Hastenteufel, Mark; Wolf, Ivo; de Simone, Raffaele; Mottl-Link, Sibylle; Meinzer, Hans-Peter

    2002-04-01

    The knowledge about the complex three-dimensional (3D) heart wall motion pattern, particular in the left ventricle, provides valuable information about potential malfunctions, e.g., myocardial ischemia. Nowadays, echocardiography (cardiac ultrasound) is the predominant technique for evaluation of cardiac function. Beside morphology, tissue velocities can be obtained by Doppler techniques (tissue Doppler imaging, TDI). Strain rate imaging (SRI) is a new technique to diagnose heart vitality. It provides information about the contraction ability of the myocardium. Two-dimensional color Doppler echocardiography is still the most important clinical method for estimation of morphology and function. Two-dimensional methods leads to a lack of information due to the three-dimensional overall nature of the heart movement. Due to this complex three-dimensional motion pattern of the heart, the knowledge about velocity and strain rate distribution over the whole ventricle can provide more valuable diagnostic information about motion disorders. For the assessment of intracardiac blood flow three-dimensional color Doppler has already shown its clinical utility. We have developed methods to produce strain rate images by means of 3D tissue Doppler echocardiography. The tissue Doppler and strain rate images can be visualized and quantified by different methods. The methods are integrated into an interactively usable software environment, making them available in clinical everyday life. Our software provides the physician with a valuable tool for diagnosis of heart wall motion.

  18. Pediatric heart surgery

    Science.gov (United States)

    Heart surgery - pediatric; Heart surgery for children; Acquired heart disease; Heart valve surgery - children ... There are many kinds of heart defects. Some are minor, and others are more serious. Defects can occur inside the heart or in the large blood vessels ...

  19. Satellite Heart

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The usefulness of China’s own global navigation system is being extended by technological breakthroughs China has successfully developed the country’s first navigation chip that is expected to be the heart of the country’s satellite-based navigation system,according to a report released on February 21. The Navigation I chip,developed by the Shanghai Fukong Hualong Micro-system

  20. Keeping the Beat: A Large Sample Study of Bouncing and Clapping to Music

    Science.gov (United States)

    Tranchant, Pauline; Vuvan, Dominique T.; Peretz, Isabelle

    2016-01-01

    The vast majority of humans move in time with a musical beat. This behaviour has been mostly studied through finger-tapping synchronization. Here, we evaluate naturalistic synchronization responses to music–bouncing and clapping–in 100 university students. Their ability to match the period of their bounces and claps to those of a metronome and musical clips varying in beat saliency was assessed. In general, clapping was better synchronized with the beat than bouncing, suggesting that the choice of a specific movement type is an important factor to consider in the study of sensorimotor synchronization processes. Performance improved as a function of beat saliency, indicating that beat abstraction plays a significant role in synchronization. Fourteen percent of the population exhibited marked difficulties with matching the beat. Yet, at a group level, poor synchronizers showed similar sensitivity to movement type and beat saliency as normal synchronizers. These results suggest the presence of quantitative rather than qualitative variations when losing the beat. PMID:27471854

  1. Modification of the algorithm for beat tracking of a musical melody

    OpenAIRE

    Khachai, M. Y.; Kobylkin, K. S.; Khachai, D. M.

    2013-01-01

    A new efficient modification of the known heuristic algorithm for real-time beat tracking is proposed. An improved formula for updating the relative frequencies of time intervals between adjacent onsets is used in the modification. The algorithm has shown good performance on the MIREX Beat Tracking test base. © 2013 Pleiades Publishing, Ltd.

  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. Beat processing is pre-attentive for metrically simple rhythms with clear accents: an ERP study.

    Science.gov (United States)

    Bouwer, Fleur L; Van Zuijen, Titia L; Honing, Henkjan

    2014-01-01

    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.

  4. Beat processing is pre-attentive for metrically simple rhythms with clear accents: an ERP study.

    Science.gov (United States)

    Bouwer, Fleur L; Van Zuijen, Titia L; Honing, Henkjan

    2014-01-01

    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. PMID:24870123

  5. Beat processing is pre-attentive for metrically simple rhythms with clear accents: An ERP study

    NARCIS (Netherlands)

    F.L. Bouwer; T.L. van Zuijen; H. Honing

    2014-01-01

    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 irrespe

  6. Keeping the Beat: A Large Sample Study of Bouncing and Clapping to Music.

    Science.gov (United States)

    Tranchant, Pauline; Vuvan, Dominique T; Peretz, Isabelle

    2016-01-01

    The vast majority of humans move in time with a musical beat. This behaviour has been mostly studied through finger-tapping synchronization. Here, we evaluate naturalistic synchronization responses to music-bouncing and clapping-in 100 university students. Their ability to match the period of their bounces and claps to those of a metronome and musical clips varying in beat saliency was assessed. In general, clapping was better synchronized with the beat than bouncing, suggesting that the choice of a specific movement type is an important factor to consider in the study of sensorimotor synchronization processes. Performance improved as a function of beat saliency, indicating that beat abstraction plays a significant role in synchronization. Fourteen percent of the population exhibited marked difficulties with matching the beat. Yet, at a group level, poor synchronizers showed similar sensitivity to movement type and beat saliency as normal synchronizers. These results suggest the presence of quantitative rather than qualitative variations when losing the beat. PMID:27471854

  7. Algorithm for identifying and separating beats from arterial pulse records

    Directory of Open Access Journals (Sweden)

    Valentinuzzi Max E

    2005-08-01

    Full Text Available Abstract Background This project was designed as an epidemiological aid-selecting tool for a small country health center with the general objective of screening out possible coronary patients. Peripheral artery function can be non-invasively evaluated by impedance plethysmography. Changes in these vessels appear as good predictors of future coronary behavior. Impedance plethysmography detects volume variations after simple occlusive maneuvers that may show indicative modifications in arterial/venous responses. Averaging of a series of pulses is needed and this, in turn, requires proper determination of the beginning and end of each beat. Thus, the objective here is to describe an algorithm to identify and separate out beats from a plethysmographic record. A secondary objective was to compare the output given by human operators against the algorithm. Methods The identification algorithm detected the beat's onset and end on the basis of the maximum rising phase, the choice of possible ventricular systolic starting points considering cardiac frequency, and the adjustment of some tolerance values to optimize the behavior. Out of 800 patients in the study, 40 occlusive records (supradiastolic- subsystolic were randomly selected without any preliminary diagnosis. Radial impedance plethysmographic pulse and standard ECG were recorded digitizing and storing the data. Cardiac frequency was estimated with the Power Density Function and, thereafter, the signal was derived twice, followed by binarization of the first derivative and rectification of the second derivative. The product of the two latter results led to a weighing signal from which the cycles' onsets and ends were established. Weighed and frequency filters are needed along with the pre-establishment of their respective tolerances. Out of the 40 records, 30 seconds strands were randomly chosen to be analyzed by the algorithm and by two operators. Sensitivity and accuracy were calculated by means

  8. Visualization of short-term heart period variability with network tools as a method for quantifying autonomic drive

    CERN Document Server

    Makowiec, Danuta; Kaczkowska, Agnieszka; Graff, Grzegorz; Wejer, Dorota; Wdowczyk, Joanna; Zarczynska-Buchowiecka, Marta; Gruchala, Marcin; Struzik, Zbigniew R

    2014-01-01

    Signals from heart transplant recipients can be considered to be a natural source of information for a better understanding of the impact of the autonomic nervous system on the complexity of heart rate variability. Beat-to-beat heart rate variability can be represented as a network of increments between subsequent $RR$-intervals, which makes possible the visualization of short-term heart period fluctuations. A network is constructed of vertices representing increments between subsequent $RR$-intervals, and edges which connect adjacent $RR$-increments. Two modes of visualization of such a network are proposed. The method described is applied to nocturnal Holter signals recorded from healthy young people and from cardiac transplant recipients. Additionally, the analysis is performed on surrogate data: shuffled RR-intervals (to display short-range dependence), and shuffled phases of the Fourier Transform of RR-intervals (to filter out linear dependences). Important nonlinear properties of autonomic nocturnal reg...

  9. Hypoplastic right-heart syndrome presenting as multiple miscarriages.

    Science.gov (United States)

    Dib, Chadi; Araoz, Philip A; Davies, Norman P; Dearani, Joseph A; Ammash, Naser M

    2012-01-01

    Reversible causes of miscarriage are many, but they affect only 1% of women who are trying to conceive. Herein, we describe the case of a 23-year-old woman who presented for evaluation of repeated miscarriages and was found to have hypoxemia and erythrocytosis. Further evaluation revealed hypoplastic right-heart syndrome with an intracardiac shunt. She underwent hybrid repair with pulmonary valve balloon valvuloplasty, followed by surgery to perform atrial septal defect closure and a Glenn anastomosis. The erythrocytosis and hypoxemia resolved, and she was able to conceive and deliver a healthy baby at term 2 years later. This is a unique case of a rare congenital heart defect that went unnoticed until adulthood, when attempts at pregnancy failed because of the associated hypoxemia. Timely and appropriate treatment led to a successful pregnancy after repeated miscarriages. This case exemplifies the need for a comprehensive medical evaluation of every woman with a history of multiple miscarriages to determine whether a reversible cause exists. PMID:22740745

  10. Assessment of vasodilator therapy in patients with severe congestive heart failure: limitations of measurements of left ventricular ejection fraction and volumes

    International Nuclear Information System (INIS)

    Although noninvasive techniques are often used to assess the effect of vasodilator therapy in patients with congestive heart failure, it is unknown whether changes in noninvasively determined left ventricular ejection fraction, volume, or dimension reliably reflect alterations in intracardiac pressure and flow. Accordingly, we compared the acute effect of sodium nitroprusside on left ventricular volume and ejection fraction (determined scintigraphically) with its effect on intracardiac pressure and forward cardiac index (determined by thermodilution) in 12 patients with severe, chronic congestive heart failure and a markedly dilated left ventricle. Nitroprusside (infused at 1.3 +/- 1.1 [mean +/- standard deviation] microgram/kg/min) caused a decrease in mean systemic arterial, mean pulmonary arterial, and mean pulmonary capillary wedge pressure as well as a concomitant increase in forward cardiac index. Simultaneously, left ventricular end-diastolic and end-systolic volume indexes decreased, but the scintigraphically determined cardiac index did not change significantly. Left ventricular ejection fraction averaged 0.19 +/- 0.05 before nitroprusside administration and increased by less than 0.05 units in response to nitroprusside in 11 of 12 patients. The only significant correlation between scintigraphically and invasively determined variables was that between the percent change in end-diastolic volume index and the percent change in pulmonary capillary wedge pressure (r . 0.68, p . 0.01). Although nitroprusside produced changes in scintigraphically determined left ventricular ejection fraction, end-systolic volume index, and cardiac index, these alterations bore no predictable relation to changes in intracardiac pressure, forward cardiac index, or vascular resistance. Furthermore, nitroprusside produced a considerably greater percent change in the invasively measured variables than in the scintigraphically determined ones

  11. 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.

  12. Observation of single- and two-photon beating between independent Raman scattering

    CERN Document Server

    Chen, Li-Qing; Zhang, Guo-Wan; Ou, Z Y; Zhang, Weiping

    2010-01-01

    By using spontaneous Raman processes in the high gain regime, we produce two independent Raman Stokes fields from an atomic ensemble. Temporal beating is observed between the two directly generated Stokes fields in a single realization. The beat frequency is found to be a result of an AC Stark frequency shift effect. However, due to the spontaneous nature of the process, the phases of the two Stokes fields change from one realization to another so that the beat signal disappears after average over many realizations. On the other hand, the beat signal is recovered in a two-photon correlation measurement, showing a two-photon interference effect. The two-photon beat signal enables us to obtain dephasing information in the Raman process. The dephasing effect is found to depend on the temperature of the atomic medium.

  13. 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.

  14. Direct visualization of mechanical beats by means of an oscillating smartphone

    CERN Document Server

    Giménez, Marcos H; Monsoriu, Juan A

    2016-01-01

    The resonance phenomenon is widely known from Physics courses. Qualitatively speaking, it takes place in a driven oscillating system whenever the driven frequency approaches the natural frequency. It is when the amplitude of the oscillations become maximal. Very closely related to this phenomenon, there is another which is very surprising too. It takes place when the driven and natural frequencies of the system are slightly different and interfere constructively and destructively, forming the so called beats. The frequency of the beats is just the difference of the interfering waves frequencies. Beats are very noticeable in acoustic systems. We all have probably perceived them in the form of periodic ups and downs in the sound intensity volume. 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 beat produced by two signals of close frequencies. The formation ...

  15. Numerical modeling of surf beat generated by moving breakpoint

    Institute of Scientific and Technical Information of China (English)

    DONG GuoHai; MA XiaoZhou; TENG Bin

    2009-01-01

    As an important hydrodynamic phenomenon in the nearshore zone, the cross-shore surf beat is nu-merically studied in this paper with a fully nonlinear Boussinesq-type model, which resolves the pri-mary wave motion as well as the long waves. Compared with the classical Boussinesq equations, the equations adopted here allow for improved linear dispersion characteristics. Wave breaking and run-up in the swash zone are included in the numerical model. Mutual interactions between short waves and long waves are inherent in the model. The numerical study of long waves is based on bichromatic wave groups with a wide range of mean frequencies, group frequencies and modulation rates. The cross-shore variation in the amplitudes of short waves and long waves is investigated. The model results are compared with laboratory experiments from the literature and good agreement is found.

  16. Numerical modeling of surf beat generated by moving breakpoint

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    As an important hydrodynamic phenomenon in the nearshore zone, the cross-shore surf beat is numerically studied in this paper with a fully nonlinear Boussinesq-type model, which resolves the primary wave motion as well as the long waves. Compared with the classical Boussinesq equations, the equations adopted here allow for improved linear dispersion characteristics. Wave breaking and run-up in the swash zone are included in the numerical model. Mutual interactions between short waves and long waves are inherent in the model. The numerical study of long waves is based on bichromatic wave groups with a wide range of mean frequencies, group frequencies and modulation rates. The cross-shore variation in the amplitudes of short waves and long waves is investigated. The model results are compared with laboratory experiments from the literature and good agreement is found.

  17. 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...

  18. The Influence of Bearing-Down Technique on the Fetal Heart Rate during the Second Stage of Labor.

    Science.gov (United States)

    Perlis, Deborah Woolley

    This experimental study contrasted the effects of sustained bearing-down efforts with short bearing-down efforts during the first twelve contractions of the second stage of labor. A single subject design with intrasubject replication was used to compare the incidence, duration, and amplitude of fetal heart rate decelerations, as well as the beat-to-beat variability of those decelerations. Neonatal outcome was evaluated with umbilical arterial cord blood pH values and the one- and five-minute APGAR scores. Thirty -two nulliparous women alternated the use of vigorous, sustained Valsalva-style bearing-down efforts with shorter efforts called minipushes every three contractions during the second stage of labor. Sixteen women began the second stage using the Valsalva-style bearing-down technique; sixteen began the second stage using the minipush. The fetal heart rate was recorded by an internal fetal scalp electrode. Uterine contractility was measured by an internal uterine pressure catheter. A repeated-measures MANOVA showed a significant interaction between the order of implementation of the bearing-down techniques and the amplitude of the fetal heart rate decelerations. A similar comparison of the duration of the decelerations showed no significant differences between the two bearing-down techniques. Likewise, analysis of the incidence of fetal heart rate decelerations and the magnitude of the beat-to-beat variability revealed no significant differences between the two techniques.

  19. Oxidized Cellulose with Different Carboxyl Content: Structure and Properties before and after Beating

    Science.gov (United States)

    Vendula, Hejlová; Miloslav, Milichovský

    Our recent studies concentrated in investigating influence of beating oxidized cellulose, with different carboxyl content, on changing their basic properties (degree of polymerization, WRV - water resistant value and X-ray diffraction). Cellulose samples of oxidized cellulose were beated by toroidal beating machine. Cellulose consists of both amorphous and crystalline regions. Cellulose consists of linear chains of poly[ß-1,4-D- anhydroglucopyranose] (C6nH10n + 2O5n + 1 (n = degree of polymerization of glucose)), which crystallize through hydrogen bonding between the chains and has cellobiose as repeat unit. Oxidized cellulose is preparing by oxidation of cellulose in the C6 position of the glucopyranose units to carboxylic group (-COOH) and polyanhydroglukuronic acid (PAGA) is arised. An other option is oxidation with sodium hypochlorite with catalytic amounts of sodium bromide and 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) under various conditions. Beating and refining or mechanical treatment of fibers in water is an important step in using pulps for papermaking. It is an energy intensive process. The purpose of the treatment is to modify fiber properties to obtain the most desirable paper machine runnability and product properties. End of beating pulps was characterized by position, when all beated pulps under mixture passed through of riddle (about sizes mesh of 50). During beating of samples about different ratio of oxidation it was found, that samples with higher contents of COOH groups in starting pulp are characterized by a significantly lower specific beating energy consumption needed to achieving the same sizes of particles. X-ray analyse shows that for non-beated oxidized cellulose was perceptible high share amorphous contents compared with beated oxidized cellulose.

  20. Heart rate and heart rate variability in pregnant dairy cows and their fetuses determined by fetomaternal electrocardiography.

    Science.gov (United States)

    Trenk, Lisa; Kuhl, Juliane; Aurich, Jörg; Aurich, Christine; Nagel, Christina

    2015-11-01

    In this study, fetomaternal electrocardiograms were recorded once weekly in cattle during the last 14 weeks of gestation. From the recorded beat-to-beat (RR) intervals, heart rate and heart rate variability (HRV) variables standard deviation of the RR interval (SDRR) and root mean square of successive RR differences (RMSSD) were calculated. To differentiate between effects of lactation and gestation, pregnant lactating (PL) cows (n = 7) and pregnant nonlactating (PNL) heifers (n = 8) were included. We hypothesized that lactation is associated with stress detectable by HRV analysis. We also followed the hypothesis that heart rate and HRV are influenced by growth and maturation of the fetus toward term. Maternal heart rate changed over time in both groups, and in PL cows, it decreased with drying-off. During the last 5 weeks of gestation, maternal heart rate increased in both groups but was lower in PL cows than in PNL heifers. Maternal HRV did not change over time, but SDRR was significantly higher in PL cows than in PNL heifers, and significant interactions of group × time existed. On the basis of HRV, undisturbed pregnancies are thus no stressor for the dam in cattle. Fetal heart rate decreased from week 14 to week 1 before birth with no difference between groups. Gestational age thus determines heart rate in the bovine fetus. The HRV variables SDRR and RMSSD increased toward the end of gestation in fetuses carried by cows but not in those carried by heifers. The increase in HRV indicates maturation of fetal cardiac regulation which may be overrun by high sympathoadrenal activity in fetuses carried by heifers as suggested by their low HRV. PMID:26279313

  1. Banding and Step-Stair Artifacts on the Cardiac-CT Caused By Pseudo-Ectopic Beats

    OpenAIRE

    Singh, Amolak; Sethi, Yash; Watkins, Sonya; Youtsey, Angela; Thomas, Angie

    2009-01-01

    Step-stair and banding artifacts may result from irregular ventricular rhythm caused by atrial fibrillation or premature ectopic ventricular contractions. In the case reported here, severe banding and misalignment artifacts occurred due to electrocardiographic noise mimicking ectopic beats. Severe EKG noise or pseudo-ectopic beats may cause rare but serious artifacts during cardiac-CT acquisition. Vendor-provided software for correcting ectopic beats can be used to remove pseudo-ectopic beats...

  2. Revealing Hearts

    DEFF Research Database (Denmark)

    Saghaug, Kristin Falck; Pattison, George; Lindgren, Peter

    2014-01-01

    Some small business owners want to balance personal values as well as economic values. “I have to follow my heart” or “it must be meaningful” some of them say. But how might they be able to know what gives meaning to the heart? The philosophical theologian Paul Tillich finds that the problem is......, in business life. In Tillich’s own terms, even preliminary concerns may point at an ultimate concern (Tillich, 1964), which can also be understood as ‘knowledge of the heart’. Our account is also connected to wider discussions concerning the nature of intuition....

  3. Heart rate variability in 1-day-old infants born at 4330 m altitude.

    Science.gov (United States)

    Mortola, J P; León-Velarde, F; Aguero, L; Frappell, P B

    1999-02-01

    In fetuses and newborn infants heart rate variability changes in conditions of acute and chronic hypoxia; we therefore asked whether heart rate variability of infants born at high altitude differed from that of low-altitude infants. Short-term recordings (4-5 min) of inter-beat intervals were obtained in 19 infants in Lima (50 m altitude) and in 15 infants in Cerro de Pasco (4330 m, barometric pressure approximately 450 mmHg, inspired oxygen pressure approximately 94 mmHg) during quiet rest in warm conditions (ambient temperature, Ta, approximately 35 degrees C). In 12 infants from each group recordings were also obtained during cooling (Ta approximately 26 degrees C). Heart rate variability was evaluated from 512 consecutive inter-beat intervals, with analysis based on time-domain and frequency-domain methods. At warm Ta, heart rate variability did not differ between the two groups. During cooling, heart rate increased only in the low-altitude group. As in the warm, during cooling most parameters of heart rate variability did not differ between the two groups. The only exception was the inter-beat interval power of the high-frequency range of the spectrum (0.15-0.4 Hz), which, at least in adults, is believed to be a reflection of vagal activity, and was greater in the high-altitude group. It is concluded that gestation at high altitude, despite its blunting effects on fetal growth, does not have a major impact on heart rate variability of the newborn. Nevertheless, the possibility that differences in response to cooling may reflect some limitation in heart rate control needs to be examined further.

  4. Immunohistochemical Distribution of Serum Proteins in Living Mouse Heart with In Vivo Cryotechnique

    International Nuclear Information System (INIS)

    In vivo cryotechnique (IVCT), which immediately cryofixes target organs in situ, was used to clarify the morphological features of beating heart tissue of living mice. IVCT was performed for diastolic heart tissue under the condition of monitoring with electrocardiogram (ECG). Other mouse hearts were prepared with conventional perfusion-fixation (PF-DH) or immersion-fixation followed by dehydration (IM-DH), and quick-freezing of resected heart tissues (FQF). Immunolocalizations of albumin, immunoglobulin G1 (IgG1), intravenously injected bovine serum albumin (BSA), and connexin 43 were examined after different intervals of BSA injection. In the case of IVCT, the exact stop time of beating mouse hearts was recorded by ECG, and open blood vessels with flowing erythrocytes were observed with less artificial tissue shrinkage than with conventional preparation methods. Both albumin and BSA were well preserved in intercalated discs and t-tubules of cardiomyocytes in addition to blood vessels and interstitial matrices. IgG1 was immunolocalized in interstitial matrices of heart tissues in addition to their blood vessels. At 4 hr after BSA injection, it was immunolocalized in the intercalated discs of cardiomyocytes and lost later at 8 hr. IVCT should prove to be more useful for the morphofunctional examination of dynamically changing heart tissue than conventional preparation methods

  5. Remote measurements of heart and respiration rates for telemedicine.

    Directory of Open Access Journals (Sweden)

    Fang Zhao

    Full Text Available Non-contact and low-cost measurements of heart and respiration rates are highly desirable for telemedicine. Here, we describe a novel technique to extract blood volume pulse and respiratory wave from a single channel images captured by a video camera for both day and night conditions. The principle of our technique is to uncover the temporal dynamics of heart beat and breathing rate through delay-coordinate transformation and independent component analysis-based deconstruction of the single channel images. Our method further achieves robust elimination of false positives via applying ratio-variation probability distributions filtering approaches. Moreover, it enables a much needed low-cost means for preventing sudden infant death syndrome in new born infants and detecting stroke and heart attack in elderly population in home environments. This noncontact-based method can also be applied to a variety of animal model organisms for biomedical research.

  6. Mechanical stimulation in the engineering of heart muscle.

    Science.gov (United States)

    Liaw, Norman Yu; Zimmermann, Wolfram-Hubertus

    2016-01-15

    Recreating the beating heart in the laboratory continues to be a formidable bioengineering challenge. The fundamental feature of the heart is its pumping action, requiring considerable mechanical forces to compress a blood filled chamber with a defined in- and outlet. Ventricular output crucially depends on venous loading of the ventricles (preload) and on the force generated by the preloaded ventricles to overcome arterial blood pressure (afterload). The rate of contraction is controlled by the spontaneously active sinus node and transmission of its electrical impulses into the ventricles. The underlying principles for these physiological processes are described by the Frank-Starling mechanism and Bowditch phenomenon. It is essential to consider these principles in the design and evaluation of tissue engineered myocardium. This review focuses on current strategies to evoke mechanical loading in hydrogel-based heart muscle engineering.

  7. Real-Time Analysis of Beats in Music for Entertainment Robots

    Directory of Open Access Journals (Sweden)

    Yue-Der Lin

    2012-12-01

    Full Text Available The dancing actions for entertainment robots are usually designed in advance and saved in a database according to the beats and rhythm of the given music. This research is devoted to developing a real-time algorithm that can detect the primary information of the music needed for the actions of entertainment robots. The computation of the proposed algorithm is very efficient and can satisfy the requirement of real-time processing by a digital signal controller. The digitized music signal is first normalized to make the algorithm robust for miscellaneous music volume. Next, the primary features of the beat for the music are extracted. Based on the extracted features, the algorithm will then identify the occurrence of beats in the music through the use of an optimized classifier. From the accumulated information of the timing for the beats, the algorithm can provide the predicted timing information of the next beat through regression analysis. The type and tempo of the given music can also be derived thereafter. The entertainment robot can thus move or dance according to the information derived by the algorithm. A graphical user interface (GUI program in LabVIEW is also utilized to observe and verify the analysis results. In this study, the ratio for correct beat detection is greater than 90%. The prediction ratio for the correct timing of beats is over 80%, and it is 100% correct for both music type and music tempo.

  8. Effects of alcohol ingestion on cardiac rhythm in patients with ischaemic heart disease.

    Science.gov (United States)

    Kentala, E; Luurila, O; Salaspuro, M P

    1976-12-01

    The effect of alcohol on cardiac rhythm was examined in ten male volunteers with a history of acute myocardial infarction. ECG monitoring with a portable ECG recorder was carried out for a period of 48 hours. After a control period of 15-18 hours an exercise test was performed and repeated after a standard dose (0.5 g/kg b.wt.) of alcohol. Then the patients were allowed to drink alcohol freely for two and half hours. The third exercise test was performed on the second morning. Heart rate at rest and sitting on a bicycle was highest in the third test, during the "hangover" period (p less than 0.05). With a submaximal work load heart rate, and also the heart rate-blood pressure pressure product, were highest after a standard dose of alcohol in the second test (p less than 0.05 and less than 0.01 respectively). The number of ectopic beats showed no significant difference in repeated exercise tests. On tape recordings, however, five of the ten patients experienced changes in cardiac rhythm after alcohol. In two patients the number of ectopic beats increased, the third patient had three successive ventricular ectopic beats after alcohol ingestion and in the fourth patient multiple sinus arrests occurred. In one patient a higher heart rate after alcohol ingestion abolished the ventricular ectopic focus seen during the control period. PMID:1008479

  9. Heart Healthy Eating

    Science.gov (United States)

    ... disease fact sheet Heart health and stroke Heart-healthy eating Heart-healthy eating is an important way to lower your risk ... and unhealthy fats. Expand All Why is heart-healthy eating important? Heart-healthy eating, along with regular exercise ...

  10. A comparative study of contractility of the heart ventricle in some ectothermic vertebrates

    Directory of Open Access Journals (Sweden)

    Sergey Kharin

    2009-07-01

    Full Text Available The purpose of this study was to analyze contractility of the heart ventricle in selected reptilian and amphibian species having the same ventricular excitation pattern. Systolic time intervals and indices of contractility of the heart ventricle were measured in anaesthetized frogs, snakes, and tortoises by use of polycardiography. The electromechanical delay was significantly shorter in tortoises compared with the other two species. The isovolumetric contraction time in frogs was approximately twofold longer than in reptiles. The pre-ejection period was the longest in frogs and the shortest in tortoises, whereas snakes were intermediate. The ejection time was slightly longer in tortoises compared with the other two species. The greatest isovolumetric contraction index and the smallest myocardial tension index corresponded to the frog and tortoise heart ventricle, respectively. The intrasystolic index in tortoises was significantly greater than in frogs, whereas quite similar to that in snakes. The frog ventricle had lower contractility compared with the reptilian one. Although ventricular contractility tended to be lower in snakes compared with tortoises, this difference was not statistically significant. Possible causes for these differences are discussed. We suppose a large variety in ventricular contractility among amphibian and reptilian species having the same ventricular activation pattern. This variety may be conditioned by heart anatomy, intracardiac shunting, lifestyles, and habitats. It can only be hypothesized that on the average, ventricular contractility is higher in reptiles compared with amphibians and in chelonians compared with snakes.

  11. 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.

  12. 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

  13. 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

  14. Excessive heart rate response to orthostatic stress in postural tachycardia syndrome is not caused by anxiety.

    Science.gov (United States)

    Masuki, Shizue; Eisenach, John H; Johnson, Christopher P; Dietz, Niki M; Benrud-Larson, Lisa M; Schrage, William G; Curry, Timothy B; Sandroni, Paola; Low, Phillip A; Joyner, Michael J

    2007-03-01

    Postural tachycardia syndrome (POTS) is characterized by excessive increases in heart rate (HR) without hypotension during orthostasis. The relationship between the tachycardia and anxiety is uncertain. Therefore, we tested whether the HR response to orthostatic stress in POTS is primarily related to psychological factors. POTS patients (n = 14) and healthy controls (n = 10) underwent graded venous pooling with lower body negative pressure (LBNP) to -40 mmHg while wearing deflated antishock trousers. "Sham" venous pooling was performed by 1) trouser inflation to 5 mmHg during LBNP and 2) vacuum pump activation without LBNP. HR responses to mental stress were also measured in both groups, and a questionnaire was used to measure psychological parameters. During LBNP, HR in POTS patients increased 39 +/- 5 beats/min vs. 19 +/- 3 beats/min in control subjects at -40 mmHg (P inflation markedly blunted the HR responses in the patients (9 +/- 2 beats/min) and controls (2 +/- 1 beats/min), and there was no HR increase during vacuum application without LBNP in either group. HR responses during mental stress were not different in the patients and controls (18 +/- 2 vs. 19 +/- 1 beats/min; P > 0.6). Anxiety, somatic vigilance, and catastrophic cognitions were significantly higher in the patients (P 0.1). These results suggest that the HR response to orthostatic stress in POTS patients is not caused by anxiety but that it is a physiological response that maintains arterial pressure during venous pooling.

  15. Quantum beats in the field ionization of Rydberg atoms in the presence of magnetic fields

    Science.gov (United States)

    Gregoric, Vincent C.; Hastings, Hannah; Carroll, Thomas J.; Noel, Michael W.

    2016-05-01

    By exciting a coherent superposition and varying its phase evolution, quantum beats in the selective field ionization of Rydberg atoms have been observed. Here, we present a study exploring the effect of electric and magnetic fields on quantum beats. Beginning with a single excited state, a coherent superposition is created by a short electric field pulse in the presence of a static magnetic field. The resulting quantum beats are then observed in the field ionization spectrum. Additionally, millimeter-wave spectroscopy is used to probe the state populations in this superposition. This work is supported by the National Science Foundation under Grants No. 1205895 and No. 1205897.

  16. 110例室性早搏定位分析及临床意义的探讨%The Positioning analyses of the Ventricular Premature Beats(VPBs) and clinic significance in 110 cases

    Institute of Scientific and Technical Information of China (English)

    肖萍

    2010-01-01

    目的 探讨室性早搏定位分析及临床意义.方法 对110例住院患者发生室性早搏QRS波群形态进行定位分析.结果 在有心脏病的患者中,室早来源于左心室的最为常见,占总人数的25%;室早来源于右心室的占19%、心底部占15%、心尖部占10%、双室及左室后壁各占5.5%.无心脏疾患的22例中无一例双室室早.结论 有心脏病患者室性早搏起源部位的定位不仅有心电图诊断价值,在临床上具有一定意义.%Objective To investigate the clinic significance of the ventricular premature beats (VPBs).Methods Positioning analyses of the QRS wave pattern of the VPBs in 110 cases of patients (heart attackers and healthy heart patients) in hospital. Results For the cases of heart-attack patients, the VPBs occurred mostly in the left ventricle, taking up 25% of the totality. In 19% cases, the VPBs occurred in the right ventricle; in 15%cases,in the bottom of the heart;in 10% cases,on the tip of the heart;in 5.5% ,in both left and right ventricles,and the same rate in the posterior left ventricular wall. In addition, in 22 cases of patients with healthy heart, no dual-chamber ventricular premature beats happened. Conclusion It' s of great ECG diagnosis value and of great clinic significance to position where the VPBs of heart attackers occur.

  17. Bluetooth Heart Rate Monitors for Spaceflight

    Science.gov (United States)

    Buxton, R. E.; West, M. R.; Kalogera, K. L.; Hanson, A. M.

    2016-01-01

    Heart rate monitoring is required for crewmembers during exercise aboard the International Space Station (ISS) and will be for future exploration missions. The cardiovascular system must be sufficiently stressed throughout a mission to maintain the ability to perform nominal and contingency/emergency tasks. High quality heart rate data are required to accurately determine the intensity of exercise performed by the crewmembers and show maintenance of VO2max. The quality of the data collected on ISS is subject to multiple limitations and is insufficient to meet current requirements. PURPOSE: To evaluate the performance of commercially available Bluetooth heart rate monitors (BT HRM) and their ability to provide high quality heart rate data to monitor crew health aboard the ISS and during future exploration missions. METHODS: Nineteen subjects completed 30 data collection sessions of various intensities on the treadmill and/or cycle. Subjects wore several BT HRM technologies for each testing session. One electrode-based chest strap (CS) was worn, while one or more optical sensors (OS) were worn. Subjects were instrumented with a 12-lead ECG to compare the heart rate data from the Bluetooth sensors. Each BT HRM data set was time matched to the ECG data and a +/-5bpm threshold was applied to the difference between the 2 data sets. Percent error was calculated based on the number of data points outside the threshold and the total number of data points. RESULTS: The electrode-based chest straps performed better than the optical sensors. The best performing CS was CS1 (1.6% error), followed by CS4 (3.3% error), CS3 (6.4% error), and CS2 (9.2% error). The OS resulted in 10.4% error for OS1 and 14.9% error for OS2. CONCLUSIONS: The highest quality data came from CS1, but unfortunately it has been discontinued by the manufacturer. The optical sensors have not been ruled out for use, but more investigation is needed to determine how to obtain the best quality data. CS2 will be

  18. Real time heart rate variability assessment from Android smartphone camera photoplethysmography: Postural and device influences.

    Science.gov (United States)

    Guede-Fernandez, F; Ferrer-Mileo, V; Ramos-Castro, J; Fernandez-Chimeno, M; Garcia-Gonzalez, M A

    2015-08-01

    The aim of this paper is to present a smartphone based system for real-time pulse-to-pulse (PP) interval time series acquisition by frame-to-frame camera image processing. The developed smartphone application acquires image frames from built-in rear-camera at the maximum available rate (30 Hz) and the smartphone GPU has been used by Renderscript API for high performance frame-by-frame image acquisition and computing in order to obtain PPG signal and PP interval time series. The relative error of mean heart rate is negligible. In addition, measurement posture and the employed smartphone model influences on the beat-to-beat error measurement of heart rate and HRV indices have been analyzed. Then, the standard deviation of the beat-to-beat error (SDE) was 7.81 ± 3.81 ms in the worst case. Furthermore, in supine measurement posture, significant device influence on the SDE has been found and the SDE is lower with Samsung S5 than Motorola X. This study can be applied to analyze the reliability of different smartphone models for HRV assessment from real-time Android camera frames processing. PMID:26737985

  19. Real time heart rate variability assessment from Android smartphone camera photoplethysmography: Postural and device influences.

    Science.gov (United States)

    Guede-Fernandez, F; Ferrer-Mileo, V; Ramos-Castro, J; Fernandez-Chimeno, M; Garcia-Gonzalez, M A

    2015-01-01

    The aim of this paper is to present a smartphone based system for real-time pulse-to-pulse (PP) interval time series acquisition by frame-to-frame camera image processing. The developed smartphone application acquires image frames from built-in rear-camera at the maximum available rate (30 Hz) and the smartphone GPU has been used by Renderscript API for high performance frame-by-frame image acquisition and computing in order to obtain PPG signal and PP interval time series. The relative error of mean heart rate is negligible. In addition, measurement posture and the employed smartphone model influences on the beat-to-beat error measurement of heart rate and HRV indices have been analyzed. Then, the standard deviation of the beat-to-beat error (SDE) was 7.81 ± 3.81 ms in the worst case. Furthermore, in supine measurement posture, significant device influence on the SDE has been found and the SDE is lower with Samsung S5 than Motorola X. This study can be applied to analyze the reliability of different smartphone models for HRV assessment from real-time Android camera frames processing.

  20. Hypothyroidism and Heart Disease

    Science.gov (United States)

    ... Hypothyroidism and Heart Disease Fact Sheet Hypothyroidism and Heart Disease January 2014 Download PDFs English Espanol Editors Alan ... hormone. Why does hypothyroidism increase your risk for heart disease? Both thyroid hormones (T4 and T3) are related ...