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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 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...

  3. 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...

  4. 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.)

  5. Race May Influence Risk for Irregular Heart Beat

    Science.gov (United States)

    ... nlm.nih.gov/medlineplus/news/fullstory_158687.html Race May Influence Risk for Irregular Heart Beat Whites ... between the heart rhythm disorder atrial fibrillation and race, a new study says. Whites with heart failure ...

  6. 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.

  7. Correlations in heart beat data as quantitative characterization of heart pathology

    International Nuclear Information System (INIS)

    Correlation between heart pathology and statistical properties of heart beat data has been studied. It is shown that heart beat data has different scaling behavior for healthy and disease cases. Possibilities to develop new monitoring technique based on the permanent control of the correlations in heart beat data are discussed. copyright 1996 American Institute of Physics

  8. "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 ...

  9. 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.

  10. Coupling Between Pecking and Heart Beat in Pigeons

    OpenAIRE

    Delius, Juan; Lindenblatt, Ulrike; Lombardi, Celia

    1986-01-01

    The electrocardiogram of pigeons was recorded while they pecked an impact transducer under operant control according to a variable ratio schedule. An analysis of the records in terms of crossaverages between heart beats and pecks. the quasi-equivalents of crosscorrelation functions, revealed that pecks and heart beats tend to coincide temporally at above chance levels according to patterns that vary from individual to individual pigeon. The mechanisms and the functions of the coupling are dis...

  11. 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

  12. [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

  13. 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.

  14. Space-Time Localization and Registration on the Beating Heart

    OpenAIRE

    Wood, Nathan A.; Waugh, Kevin; Liu, Tian Yu Tommy; Zenati, Marco A.; Riviere, Cameron N.

    2013-01-01

    This paper presents a framework for localizing a miniature epicardial crawling robot, HeartLander, on the beating heart using only 6-degree-of-freedom position measurements from an electromagnetic position tracker and a dynamic surface model of the heart. Using only this information, motion and observation models of the system are developed such that a particle filter can accurately estimate not only the location of the robot on the surface of the heart, but also the pose of the heart in the ...

  15. Three-dimensional color Doppler reconstruction of intracardiac blood flow in patients with different heart valve diseases.

    Science.gov (United States)

    De Simone, R; Glombitza, G; Vahl, C F; Meinzer, H P; Hagl, S

    2000-12-15

    An improved perception of the magnitude and dynamics of intracardiac flow disturbances has been made possible by the advent of 3-dimensional (3-D) color Doppler, a new diagnostic procedure developed at our institution. This study describes the new insights derived from 3-D reconstruction of color Doppler flow patterns in patients with different heart valve diseases. The color Doppler flow data from 153 multiplanar transesophageal or transthoracic echocardiographic examinations has been obtained from 133 patients with heart valve disease; 73 patients had mitral regurgitation, 15 had mitral stenosis, 18 had aortic regurgitation, 26 had aortic stenosis, and 21 patients had tricuspid regurgitation. Four patients had pulmonary regurgitation associated with mitral valve disease. The 3-D reconstructions of color Doppler flow signals were accomplished by means of the "Heidelberg Raytracing model," developed at our institution. The 3-D color Doppler reconstructions were obtained in all patients. The 3-D images revealed for the first time the complex spatial distribution of the blood flow abnormalities in the heart chambers caused by different heart valve diseases. New patterns of intracardiac blood flow disturbances were observed and classified. Three-dimensional color Doppler provides a unique noninvasive method that can be easily applied for studying intracardiac blood flow disturbances in clinical practice. PMID:11113410

  16. 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.

  17. 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...

  18. 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

  19. Ion channels and beating heart: the players and the music

    Directory of Open Access Journals (Sweden)

    Charles Antzelevitch

    2011-12-01

    Full Text Available Soft gentle music accompanies us throughout our lifetime; it is the music of our heart beating. Although at times it is questionable as to who serves as conductor of the orchestra, there is little doubt that our ion channels are the main players. Whenever one of them plays too loudly, too softly or simply off key, disharmony results, sometimes leading to total disruption of the rate and rhythm. Ion channels can disrupt the music of our heart by different mechanisms. Sometimes their function is correct, but their expression is altered by underlying cardiac diseases (i.e. heart failure; sometimes the defect is in their structure, because of an underlying genetic defect, and in this case a channelopathy is present.

  20. Mapping of Human Heart Beat Dynamics by Atomic Magnetometers

    Science.gov (United States)

    Weis, A.; Bison, G.; Wynands, R.

    2005-05-01

    Stimulated by recent progress in laser-based optical magnetometry and in developments of powerful signal denoising techniques we initiated the development of a low-cost laser-driven optically pumped magnetometer (OPM) for biomagnetic applications. The OPM uses optically pumped cesium atoms in glass cells of a few cm3. Its sensitivity (<70 fT in 1 Hz bandwidth), bandwidth (140 Hz), and spatial resolution (cm) were optimized for the two-dimensional mapping of the magnetic field produced above the chest by the beating human heart. Signal averaging using an electrocardiographic signal as a reference and gradiometric detection reduces residual noise significantly so that the dynamics of the heart field can be displayed a movie. We discuss the principle of the technique and give a status report on ongoing work towards the development of a multichannel device.

  1. 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.

  2. 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)

  3. 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...

  4. 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.

  5. 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

  6. Total Artificial Heart Bridge to Transplantation for a Patient With Occult Intracardiac Malignancy: Case Report.

    Science.gov (United States)

    Reich, H; Czer, L; Bannykh, S; De Robertis, M; Wolin, E; Amersi, F; Moriguchi, J; Kobashigawa, J; Arabia, F

    2015-09-01

    Malignancy is the leading cause of long-term morbidity and mortality after heart and other solid organ transplantation; therefore, great emphasis is placed on pre- and post-transplantation cancer screening. Even with meticulous screening during evaluation for heart transplant candidacy, an occult cancer may not be apparent. Here, we share the case of a 51-year-old man with refractory heart failure who underwent total artificial heart implantation as a bridge to transplantation with the surprise finding of an isolated deposit of metastatic carcinoid tumor nested within a left ventricular papillary muscle in his explanted heart. The primary ileal carcinoid tumor was identified and resected completely. After remaining cancer-free for 14 months, he was listed for heart transplantation and was transplanted 2 months later. He is currently 3.5 months out from heart transplantation and doing well, without evidence of recurring malignancy. PMID:26361702

  7. 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 ...

  8. 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.

  9. Towards Localizing on the Surface of the Beating Heart

    OpenAIRE

    Wood, Nathan A.; Liu, Tian Yu Tommy; Waugh, Kevin; Zenati, Marco A.; Riviere, Cameron N.

    2012-01-01

    This paper presents preliminary work toward localizing on a surface which undergoes periodic deformation, as an aspect of research on HeartLander, a miniature epicardial crawling robot. Using only position measurements from the robot, the aim of this work is to use the nonuniform movements of the heart as features to aid in localization. Using a particle filter, with motion and observation models which accurately model the robotic system, registration and localization parameters can be quickl...

  10. 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)

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

    OpenAIRE

    Setareh Rezakhani; Mehdi Aliyari Shoorehdeli; Azam Ghasemi

    2014-01-01

    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...

  12. 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.

  13. 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...

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

    International Nuclear Information System (INIS)

    Objective: To evaluate the feasibility of dual-source computed tomography (DSCT) coronary angiography in a population with premature heart-beats. Methods: Seventy patients with suspected coronary artery disease and premature heart-beats were routinely imaged on a DSCT scanner (Somatom Definition, Siemens AG, Germany). The images were reconstmcted before and after ECG editing. Two readers independently assessed image quality of all coronary segments using a four-point grading scale from excellent (1) to non-assessable (4). The results of the two groups were compared with a paired t-test, and a P value of less than 0.05 was considered significant. Results: The mean heart rate during examination ranged from 49 to 111 bpm[ mean(70.7±12.4) bpm]. Twenty-eight of 70 patients with relatively small variability of the heart rate [(41.0±18.4) bpm] got diagnostic image quality without ECG editing. In other 42 patients with larger variability of the heart rate [(71.4±28.7) bpm], the mean image quality scores were 2.09±1.27 and 1.50±0.79 before and after ECG editing, there was a significant difference (t= 13.764, P2=121.846, P<0.01). Finally, the diagnostic image accounted 98.0% (1014/1035) in all segments of 70 patients. Conclusion: DSCT can provide diagnostic images for patients with premature heart-beats. The image quality in patients with larger variability of the heart rate can be significantly improved through ECG editing. (authors)

  15. 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/...

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

    OpenAIRE

    Ercan, Abdulkadir; Velioğlu, Yusuf; Ercan, Arzu; Gürbüz, Orçun; Özkan, Hakan; Karal, İlker Hasan; Biçer, Murat; Ener, Serdar

    2011-01-01

    Objectives: This prospective, randomised, controlled, clinical study was planned to determine the effect of trimetazidine and glucose - insulin - potassium (GIK) on myocardial ischemia-rep­erfusion during beating heart coronary artery bypass surgery. Materials and methods: Patients (n=45) with coronary artery disease who required beating heart coronary artery bypass grafting were randomly allocated into three groups. Patients in group 1 (n=15) was recevied trimetazidine (20 mg x 3...

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

    OpenAIRE

    Abdulkadir Ercan; Yusuf Velioğlu; Arzu Ercan; Orçun Gürbüz; Hakan Özkan; İlker Hasan Karal; Murat Biçer; Serdar Ener

    2011-01-01

    Objectives: This prospective, randomised, controlled, clinical study was planned to determine the effect of trimetazidine and glucose - insulin - potassium (GIK) on myocardial ischemia-reperfusion during beating heart coronary artery bypass surgery.Materials and methods: Patients (n=45) with coronary artery disease who required beating heart coronary artery bypass grafting were randomly allocated into three groups. Patients in group 1 (n=15) was recevied trimetazidine (20 mg x 3 per day) 7 da...

  18. Multimodal heart beat detection using signal quality indices.

    Science.gov (United States)

    Johnson, Alistair E W; Behar, Joachim; Andreotti, Fernando; Clifford, Gari D; Oster, Julien

    2015-08-01

    The electrocardiogram (ECG) is a well studied signal from which many clinically relevant parameters can be derived, such as heart rate. A key component in the estimation of these parameters is the accurate detection of the R peak in the QRS complex. While corruption of the ECG by movement artefact or sensor failure can result in poor delineation of the R peak, use of synchronously measured signals could allow for resolution of the R peak even scenarios with poor quality ECG recordings. Robust estimation of R peak locations from multimodal signals facilitates real time monitoring and is likely to reduce false alarms due to inaccurate derived parameters.We propose a method which fuses R peaks detected on the ECG using an energy detector with those detected on the arterial blood pressure (ABP) waveform using the length transform. A signal quality index (SQI) for the two signals is then derived. The ECG SQI is based upon the agreement between two distinct peak detectors. The ABP SQI estimates the blood pressure at various phases in the cardiac cycle and only accepts the signal as good quality if the values are physiologically plausible. Detections from these two signals were merged by selecting the R peak detections from the signal with a higher SQI. The approach presented in this paper was evaluated on datasets provided for the Physionet/Computing in Cardiology Challenge 2014. The algorithm achieved a sensitivity of 95.1% and positive predictive value of 89.3% on an external evaluation set, and achieved a score of 91.5%.The method here demonstrated excellent performance across a variety of signal morphologies collected during clinical practice. Fusion of R peaks from other signals has the potential to provide informed estimates of the R peak location in situations where the ECG is noisy or completely absent. Source code for the algorithm is made available freely online. PMID:26218060

  19. What makes the heart of Boa constrictor (Squamata: Boidae beat faster?

    Directory of Open Access Journals (Sweden)

    João Fabrício Mota Rodrigues

    2015-02-01

    Full Text Available Body size is highly correlated with metabolism, which in turn influences physiological rates such as heart rate. In general, heart rate is negatively influenced by the size of animal's body, but there is insufficient data corroborating this pattern in snakes. This study evaluated how body size affects heart rate in captive Boa constrictor Linnaeus, 1758. We measured the heart rate of 30 snakes using digital palpation and evaluated how this rate is influenced by body mass and sex using Analysis of Covariance (ANCOVA. The heart rate of the snakes was 58.8 ± 6.7 bpm (beats per minute. Body size, estimated as log-transformed body mass, negatively influenced heart rate (F1,28 = 10.27, p = 0.003, slope = -0.00004, R2 = 0.27, but sex had no effect (F1,27 = 0.07, p = 0.80. In conclusion, this result corroborates the negative relationship between body size and heart rate for snakes and reinforces the influence of related metabolic characteristics, such as body size, on the physiological parameters of snakes.

  20. 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

  1. 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.

  2. 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

  3. Short and long time blood pressure, heart beat and respiratory oscillation control analysed by XYt graphs

    Czech Academy of Sciences Publication Activity Database

    Jurák, Pavel; Halámek, Josef; Kára, T.; Lanfranchi, P.; Souček, M.

    Brno: University of Technology VUTIUM Press, 2002 - (Kozumplík, J.; Provazník, I.; Jan, J.), s. 226 - 229 ISBN 80-214-2633-0. ISSN 1211-412X. [BIOSIGNAL 2002. Brno (CZ), 25.06.2002-28.06.2002] R&D Projects: GA ČR GA102/00/1262; GA ČR GA102/02/1339 Institutional research plan: CEZ:AV0Z2065902 Keywords : heart beat interactions * autonomic nervous system * respiration monitoring Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery

  4. Design a Wearable Device for Blood Oxygen Concentration and Temporal Heart Beat Rate

    Science.gov (United States)

    Myint, Cho Zin; Barsoum, Nader; Ing, Wong Kiing

    2010-06-01

    The wireless network technology is increasingly important in healthcare as a result of the aging population and the tendency to acquire chronic disease such as heart attack, high blood pressure amongst the elderly. A wireless sensor network system that has the capability to monitor physiological sign such as SpO2 (Saturation of Arterial Oxygen) and heart beat rate in real-time from the human's body is highlighted in this study. This research is to design a prototype sensor network hardware, which consists of microcontroller PIC18F series and transceiver unit. The sensor is corporate into a wearable body sensor network which is small in size and easy to use. The sensor allows a non invasive, real time method to provide information regarding the health of the body. This enables a more efficient and economical means for managing the health care of the population.

  5. 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.

  6. 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

  7. 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.

  8. Non-invasive integrative analysis of contraction energetics in intact beating heart.

    Science.gov (United States)

    Deschodt-Arsac, Véronique; Calmettes, Guillaume; Gouspillou, Gilles; Chapolard, Mathilde; Raffard, Gérard; Rouland, Richard; Jais, Pierre; Haissaguerre, Michel; Dos Santos, Pierre; Diolez, Philippe

    2013-01-01

    The comprehensive study of human pathologies has revealed the complexity of the interactions involved in cardiovascular physiology. The recent validation of system's biology approaches - like our Modular Control and Regulation Analysis (MoCA) - motivates the current interest for new integrative and non-invasive analyses that could be used for medical study of human heart contraction energetics. By considering heart energetics as a supply-demand system, MoCA gives access to integrated organ function and brings out a new type of information, the "elasticities", which describe in situ the regulation of both energy demand and supply by cellular energetic status. These regulations determine the internal control of contraction energetics and may therefore be a key to the understanding of the links between molecular events in pathologies and whole organ function/dysfunction. A wider application to the effects of cardiac drugs in conjunction with the direct study of heart pathologies may be considered in the near future. MoCA can potentially be used not only to detect the origin of the defects associated with the pathology (elasticity analyses), but also to provide a quantitative description of how these defects influence global heart function (regulation analysis) and therefore open new therapeutic perspectives. Several key examples of current applications to intact isolated beating heart are presented in this paper. The future application to human pathologies will require the use of non-invasive NMR techniques for the simultaneous measurement of energy status ((31)P NMR) and heart contractile activity (3D MRI). This article is part of a Directed Issue entitled: Bioenergetic dysfunction, adaptation and therapy. PMID:22789933

  9. [New approach in the surgical treatment of mitral regurgitation: beating heart transapical neochord implantation].

    Science.gov (United States)

    Ruttkay, Tamás; Jancsó, Gábor; Gombocz, Károly; Gasz, Balázs

    2016-05-01

    Severe mitral regurgitation due to prolapse of the valve demands early surgical intervention. Recently artificial chord implantation is the prefered solution, which requires cardioplegia and application of cardiopulmonary bypass using the left atrial approach. Transoesophageal echocardiography guided transapical neochord implantation is an emerging new technique for the treatment of mitral regurgitation. It enables the operation through left minithoracotomy on beating heart using a special instrument introduced into the left ventricle. Acute procedural success rates in different centres vary between 86 and 100%. According to reports, 92% of the patients do not require additional intervention at the 3-month follow-up. Continuous integration of data resulting improved outcomes supports the hope that this novel, less-invasive technique will be applied widely for the treatment of mitral regurgitation. PMID:27106725

  10. 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. PMID:18555104

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. 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)

  17. 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

  18. [Flowmetric assessment of coronary bypass grafts in the conditions of artificial circulation and on the beating heart].

    Science.gov (United States)

    Bazylev, V V; Nemchenko, E V; Karnakhin, V A; Pavlov, A A; Mikulyak, A I

    2016-01-01

    Advantages and shortcomings of aortocoronary bypass grafting on the beating heart and in the conditions of artificial circulation (AC) have long been discussed. The data on patency of bypass grafts in the remote period are indicative of comparable results of operations with and without AC or advantages of using AC. In order to determine benefits of each method it is necessary to reveal intraoperative predictors of bypass grafts occlusion in the remote period. We analyzed the results of ultrasound flowmetry of the blood flow through the left internal thoracic artery during bypass grafting of the anterior descending artery with the use of AC and on the beating heart. A retrospective study included a total of 352 patients subdivided into 2 groups: Group One was composed of 120 patients undergoing surgery in the conditions of AC and Group Two comprised 232 patients subjected to similar operations on the beating heart. Blood flow was measured with the help of flowmeter VeryQ MediStim® after termination of AC and inactivation of heparin by protamine, with systolic pressure of 100-110 mm Hg. There were no statistically significant differences between the groups by the diameter and degree of stenosis of the anterior descending artery, diameter of the left internal thoracic artery. The mean volumetric blood flow velocity (Qmean) along the shunts in Group One was higher (p=0.01). No statistically significant differences by the pulsatility index (PI) between the groups were revealed (p=0.2). A conclusion was drawn that coronary bypass grafting of the anterior descending artery by the left internal thoracic artery in the conditions of artificial circulation made it possible to achieve higher volumetric velocity of blood flow through the conduit as compared with operations on the beating heart, with similar resistance index. The immediate results of the operations with the use of the both techniques did not differ. PMID:27100540

  19. 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.

  20. 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...

  1. Simulation of Ectopic Pacemakers in the Heart: Multiple Ectopic Beats Generated by Reentry inside Fibrotic Regions

    OpenAIRE

    Bruno Gouvêa de Barros; Rodrigo Weber dos Santos; Marcelo Lobosco; Sergio Alonso

    2015-01-01

    The inclusion of nonconducting media, mimicking cardiac fibrosis, in two models of cardiac tissue produces the formation of ectopic beats. The fraction of nonconducting media in comparison with the fraction of healthy myocytes and the topological distribution of cells determines the probability of ectopic beat generation. First, a detailed subcellular microscopic model that accounts for the microstructure of the cardiac tissue is constructed and employed for the numerical simulation of action...

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

    Directory of Open Access Journals (Sweden)

    Jarbas Jakson Dinkhuysen

    2011-12-01

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

  3. 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)

  4. 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.

  5. 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

  6. What makes the heart of Boa constrictor (Squamata: Boidae) beat faster?

    OpenAIRE

    João Fabrício Mota Rodrigues; Roberta da Rocha Braga; Thaís Helena Alencar Ferreira; Estéfanni de Castro Pinheiro; Géssica dos Santos Araújo; Diva Maria Borges-Nojosa

    2015-01-01

    Body size is highly correlated with metabolism, which in turn influences physiological rates such as heart rate. In general, heart rate is negatively influenced by the size of animal's body, but there is insufficient data corroborating this pattern in snakes. This study evaluated how body size affects heart rate in captive Boa constrictor Linnaeus, 1758. We measured the heart rate of 30 snakes using digital palpation and evaluated how this rate is influenced by body mass and sex using Analysi...

  7. 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

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

    Science.gov (United States)

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

    2014-01-01

    Background We previously reported that induced Pluripotent Stem Cell-derived cardiomyocytes (iPSC-CM) manifest beat rate variability (BRV) resembling heart rate variability (HRV) in human sinoatrial node (SAN). We now hypothesized the BRV-HRV continuum originates in pacemaker cells. Objective To investigate whether cellular BRV is a source of HRV dynamics, we hypothesized three-levels of interaction among different cardiomyocyte entities: (1) single pacemaker cells, (2) networks of electrically coupled pacemaker cells and (3) in situ SAN. Methods We measured BRV/HRV properties in single pacemaker cells, iPSC-derived contracting embryoid bodies (EBs) and electrocardiograms from the same individual. Results Pronounced BRV/HRV were present at all three levels. Coefficient of variance (COV) of inter-beat intervals (IBI) and Poincaré plot SD1 and SD2 in single cells were 20x > EBs (P0.05). We also compared BRV magnitude among single cells, small (~5-10 cells) and larger EBs (>10 cells): BRV indices progressively increased (P<0.05) as cell number decreased. Disrupting intracellular Ca2+ handling markedly augmented BRV magnitude, revealing a unique bi-modal firing pattern, suggesting intracellular mechanisms contribute to BRV/HRV and the fractal behavior of heart rhythm. Conclusions The decreased BRV magnitude in transitioning from single cell to EB suggests HRV of hearts in situ originates from summation and integration of multiple cell-based oscillators. Hence, complex interactions among multiple pacemaker cells and intracellular Ca2+ handling determine HRV in humans and isolated cardiomyocyte networks. PMID:25052725

  9. Saline contrast echocardiography for the detection of patent foramen ovale in hypoxia: a validation study using intracardiac echocardiography.

    Science.gov (United States)

    Fenster, Brett E; Curran-Everett, Douglas; Freeman, Andrew M; Weinberger, Howard D; Kern Buckner, J; Carroll, John D

    2014-04-01

    Although the "3 beat rule" is widely utiized to discriminate patent foramen ovale (PFO)-mediated right-to-left shunt (RTLS) from intrapulmonary RTLS using saline contrast transthoracic echocardiography (SCE), SCE diagnostic performance has yet to be validated using an invasive intracardiac standard. Percutaneous PFO occluder placement was recently shown to ameliorate hypoxia in patients with suspected PFO-mediated RTLS. We evaluated the ability of SCE to predict PFO presence and size using intracardiac echocardiography (ICE) as a gold standard in a hypoxic cohort. Sixty-three hypoxic patients with suspected PFO-mediated RTLS who underwent SCE at rest, with Valsalva maneuver, and with cough prior to ICE were evaluated retrospectively. PFO RTLS was defined by ICE findings including PFO anatomy, RTLS by saline contrast and color Doppler, and probe patency. SCE shunt severity and timing of left heart saline target appearance were compared to the presence of ICE-defined PFO RTLS. Forty-seven patients (75%) met criteria for PFO-mediated RTLS. A 4 beat cutoff for resting SCE provided optimal diagnostic performance for detection of PFO-mediated RTLS with a 71% sensitivity, 94% specificity, and 97% positive predictive value (PPV). Valsalva and cough maneuvers improved sensitivity compared to rest SCE (89% and 80%, respectively). Valsalva SCE shunt severity more accurately predicted PFO size than resting SCE. In contrast to the widely accepted "3 beat rule," resting SCE for the detection of PFO RTLS in a hypoxic population performs optimally using a 4-cycle cutoff with both excellent specificity and PPV. PMID:24138568

  10. 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.

  11. "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…

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

    Directory of Open Access Journals (Sweden)

    Abdulkadir Ercan

    2011-12-01

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

  13. 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.

  14. 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.

  15. Influence of ectopic heart beats in gated ventricular blood-pool studies

    International Nuclear Information System (INIS)

    Direct data collection from ventricular blood-pool studies were stored in frame mode in a computer and by means of a modified tape recorder, the blood-pool image and ECG were recorded on tape. At the end of the study the tape data were replayed into the computer. The ECG signal was passed through a trigger circuit that detected the R wave which was sampled by the computer once every msec. Contractions outside of the desired range could be rejected along with the subsequent contraction. Of seven patients whose calculated ejection fractions were changed by more than 0.03, all had frequent (one in 20) ectopic contractions. The distorted ventricular volume curves were effectively restructured by the constraining procedure, changing the end-systolic volume and EF. Computer modeling showed a linear relationship between the percent of ectopic contractions and the underestimate of ejection fraction. One ectopic beat in ten led to a 5% underestimate of EF

  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. PMID:25570435

  18. Hearts beating through decellularized scaffolds: whole-organ engineering for cardiac regeneration and transplantation.

    Science.gov (United States)

    Zia, Sonia; Mozafari, Masoud; Natasha, G; Tan, Aaron; Cui, Zhanfeng; Seifalian, Alexander M

    2016-08-01

    Whole-organ decellularization and tissue engineering approaches have made significant inroads during recent years. If proven to be successful and clinically viable, it is highly likely that this field would be poised to revolutionize organ transplantation surgery. In particular, whole-heart decellularization has captured the attention and imagination of the scientific community. This technique allows for the generation of a complex three-dimensional (3D) extracellular matrix scaffold, with the preservation of the intrinsic 3D basket-weave macroarchitecture of the heart itself. The decellularized scaffold can then be recellularized by seeding it with cells and incubating it in perfusion bioreactors in order to create functional organ constructs for transplantation. Indeed, research into this strategy of whole-heart tissue engineering has consequently emerged from the pages of science fiction into a proof-of-concept laboratory undertaking. This review presents current trends and advances, and critically appraises the concepts involved in various approaches to whole-heart decellularization and tissue engineering. PMID:25739987

  19. 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...

  20. RF communication with implantable wireless device: effects of beating heart on performance of miniature antenna

    OpenAIRE

    Murphy, Olive H.; Borghi, Alessandro; Bahmanyar, Mohammad Reza; McLeod, Christopher N.; Navaratnarajah, Manoraj; Yacoub, Magdi; Toumazou, Christofer

    2014-01-01

    The frequency response of an implantable antenna is key to the performance of a wireless implantable sensor. If the antenna detunes significantly, there are substantial power losses resulting in loss of accuracy. One reason for detuning is because of a change in the surrounding environment of an antenna. The pulsating anatomy of the human heart constitutes such a changing environment, so detuning is expected but this has not been quantified dynamically before. Four miniature implantable anten...

  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. 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

  3. Repair of double-chambered right ventricle using right ventricular outflow chamber ventriculotomy via left intercostal thoracotomy under beating heart in two dogs

    OpenAIRE

    Keiichi Sato; Isamu Kanemoto; Kippei Mihara; Koudai Kawase; Takuya Mori; Misato Ohashi; Hirokazu Abe; Shuichi Chimura

    2014-01-01

    Double-chambered right ventricle was diagnosed in two dogs, one of them a pup and the other full grown. Both dogs underwent surgery using the novel approach of right ventricular outflow chamber ventriculotomy via left intercostal thoracotomy with moderate hypothermia and moderate pump flow cardiopulmonary bypass under beating heart. No major complication occurred during and after the operation. On continuous wave Doppler echocardiography, the pressure gradient across the stenosis in the right...

  4. Intracardiac Thrombosis in Sickle Cell Disease.

    Science.gov (United States)

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

    2016-03-01

    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 evidence of hemolytic anemia, thrombocytopenia, respiratory distress, fever, jaundice, and abnormal liver function and coagulation tests, accompanied by clot formation on the Eustachian valve of the inferior vena cava in the right atrium and also a long and worm-like thrombus in the right ventricle. Therapeutic plasma exchange improved her clinical condition, and her intracardiac thrombus was completely resolved after 1 week. Echocardiography, as a simple and inexpensive imaging modality, had a significant role in the diagnosis and follow-up of this patient. PMID:26989287

  5. Intracardiac Thrombosis in Sickle Cell Disease

    Directory of Open Access Journals (Sweden)

    Marzieh Nikparvar

    2016-03-01

    Full Text Available 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 evidence of hemolytic anemia, thrombocytopenia, respiratory distress, fever, jaundice, and abnormal liver function and coagulation tests, accompanied by clot formation on the Eustachian valve of the inferior vena cava in the right atrium and also a long and worm-like thrombus in the right ventricle. Therapeutic plasma exchange improved her clinical condition, and her intracardiac thrombus was completely resolved after 1 week. Echocardiography, as a simple and inexpensive imaging modality, had a significant role in the diagnosis and follow-up of this patient.

  6. Heart rate monitoring on the stroke unit. What does heart beat tell about prognosis? An observational study

    Directory of Open Access Journals (Sweden)

    Stypmann Jörg

    2011-04-01

    Full Text Available Abstract Background Guidelines recommend maintaining the heart rate (HR of acute stroke patients within physiological limits; data on the frequency and predictors of significant deviations from these limits are scarce. Methods Demographical data, stroke risk factors, NIH stroke scale score, lesion size and location, and ECG parameters were prospectively assessed in 256 patients with ischemic stroke. Patients were continuously monitored for at least 24 hours on a certified stroke unit. Tachycardia (HR ≥120 bpm and bradycardia (HR Results HR ≥120 bpm occurred in 39 patients (15%. Stroke severity (larger lesion size/higher NIHSS-score on admission, atrial fibrillation and HR on admission predicted its occurrence. HR Conclusions Significant tachycardia and bradycardia are frequent phenomena in acute stroke; however they do not independently predict clinical course or outcome. Continuous monitoring allows detecting rhythm disturbances in stroke patients and allows deciding whether urgent medical treatment is necessary.

  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. 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.

  9. 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.

  10. 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

  11. A multidrug cocktail approach attenuates ischemic-type biliary lesions in liver transplantation from non-heart-beating donors.

    Science.gov (United States)

    Deng, Yilei; Zhao, Longshuan; Lu, Xu

    2016-06-01

    Ischemic-type biliary lesions (ITBL) are the most troublesome biliary complication after liver transplantation (LT) from non-heart-beating donors (NHBD) and frequently result in death or re-transplantation. In transplantation process, warm ischemia (WI) in the donor, cold ischemia and reperfusion injury in the recipient altogether inducing ischemia-reperfusion injury (IRI) is strongly associated with ITBL. This is a cascading injury process, involving in a complex series of inter-connecting events causing variety of cells activation and damage associated with the massive release of inflammatory cytokines and generation of reactive oxygen species (ROS). These damaged cells such as sinusoidal endothelial cells (SECs), Kupffer cells (KCs), hepatocytes and biliary epithelial cells (BECs), coupled with immunological injury and bile salt toxicity altogether contribute to ITBL in NHBD LT. Developed therapeutic strategies to attenuate IRI are essential to improve outcome after LT. Among them, single pharmaceutical interventions blocking a specific pathway of IRI in rodent models play an absolutely dominant role, and show a beneficial effect in some given controlled experiments. But this will likely prove ineffective in complex clinical setting in which more risk parameters are involved. Therefore, we intend to design a multidrug cocktail approach to block different pathways on more than one stage (WI, cold ischemia and reperfusion) of the process of IRI-induced ITBL simultaneously. This multidrug cocktail will include six drugs containing streptokinase, epoprostenol, thiazolidinediones (TZDs), N-Acetylcysteine (NAC), hemin and tauroursodeoxycholic acid (TUDC). These drugs show protective effects by targeting the different key events of IRI, such as anti-inflammatory, anti-fibrosis, anti-oxidation, anti-apoptosis and reduced bile salt toxicity. Ideally, the compounds, dosage, and method of application of drugs included in cocktail should not be definitive. We can consider

  12. 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

  13. 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.

  14. 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.

  15. 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

  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. Repair of double-chambered right ventricle using right ventricular outflow chamber ventriculotomy via left intercostal thoracotomy under beating heart in two dogs

    Directory of Open Access Journals (Sweden)

    Keiichi Sato

    2014-05-01

    Full Text Available Double-chambered right ventricle was diagnosed in two dogs, one of them a pup and the other full grown. Both dogs underwent surgery using the novel approach of right ventricular outflow chamber ventriculotomy via left intercostal thoracotomy with moderate hypothermia and moderate pump flow cardiopulmonary bypass under beating heart. No major complication occurred during and after the operation. On continuous wave Doppler echocardiography, the pressure gradient across the stenosis in the right ventricle decreased from 130 mmHg pre-operatively to 40 mmHg post-operatively at 1 year 5 months in the adult dog, and from 209 mmHg pre-operatively to 47 mmHg post-operatively at 1 year in the pup. Both dogs are active without clinical signs.

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

    International Nuclear Information System (INIS)

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

  19. 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...

  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. 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 ...

  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. 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?...

  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. Isoproterenol directs hair follicle-associated pluripotent (HAP) stem cells to differentiate in vitro to cardiac muscle cells which can be induced to form beating heart-muscle tissue sheets.

    Science.gov (United States)

    Yamazaki, Aiko; Yashiro, Masateru; Mii, Sumiyuki; Aki, Ryoichi; Hamada, Yuko; Arakawa, Nobuko; Kawahara, Katsumasa; Hoffman, Robert M; Amoh, Yasuyuki

    2016-03-01

    Nestin-expressing hair-follicle-associated pluripotent (HAP) stem cells are located in the bulge area of the follicle. Previous studies have shown that HAP stem cells can differentiate to neurons, glia, keratinocytes, smooth muscle cells, and melanocytes in vitro. HAP stem cells effected nerve and spinal cord regeneration in mouse models. Recently, we demonstrated that HAP stem cells differentiated to beating cardiac muscle cells. The differentiation potential to cardiac muscle cells was greatest in the upper part of the follicle. The beat rate of the cardiac muscle cells was stimulated by isoproterenol. In the present study, we observed that isoproterenol directs HAP stem cells to differentiate to cardiac muscle cells in large numbers in culture compared to HAP stem cells not supplemented with isoproterenol. The addition of activin A, bone morphogenetic protein 4, and basic fibroblast growth factor, along with isoproternal, induced the cardiac muscle cells to form tissue sheets of beating heart muscle cells. These results demonstrate that HAP stem cells have great potential to form beating cardiac muscle cells in tissue sheets. PMID:27104748

  6. 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.

  7. Assessment of intracardiac masses by transesophageal echocardiography.

    OpenAIRE

    DeVille, J B; Corley, D; Jin, B S; de Castro, C M; Hall, R J; Wilansky, S

    1995-01-01

    Transesophageal echocardiography and 2-dimensional transthoracic echocardiography have proved to be extremely valuable in the diagnosis of cardiac masses. In this report, we review the echocardiographic findings, clinical history, and histopathologic findings in 21 patients with intracardiac masses who underwent transthoracic echocardiography, transesophageal echocardiography, or both, at our institution. Of these patients, 14 had benign masses and 7 had malignant tumors. The potential role o...

  8. Classification and segmentation of intracardiac masses in cardiac tumor echocardiograms.

    Science.gov (United States)

    Strzelecki, Michal; Materka, Andrzej; Drozdz, Jaroslaw; Krzeminska-Pakula, Maria; Kasprzak, Jaroslaw D

    2006-03-01

    This paper describes an automatic method for classification and segmentation of different intracardiac masses in tumor echocardiograms. Identification of mass type is highly desirable, since to different treatment options for cardiac tumors (surgical resection) and thrombi (effective anticoagulant treatment) are possible. Correct diagnosis of the character of intracardiac mass in a living patient is a true challenge for a cardiologist; therefore, an objective image analysis method may be useful in heart diseases diagnosis. Image texture analysis is used to distinguish various types of masses. The presented methods assume that image texture encodes important histological features of masses and, therefore, texture numerical parameters enable the discrimination and segmentation of a mass. The recently developed technique based on the network of synchronized oscillators is proposed for the image segmentation. This technique is based on a 'temporary correlation' theory, which attempts to explain scene recognition as it would be performed by a human brain. This theory assumes that different groups of neural cells encode different properties of homogeneous image regions (e.g. shape, color, texture). Monitoring of temporal activity of cell groups leads to scene segmentation. A network of synchronized oscillators was successfully used for segmentation of Brodatz textures and medical textured images. The advantage of this network is its ability to detect texture boundaries. It can be also manufactured as a VLSI chip, for a very fast image segmentation. The accuracy of locating of analyzed tissues in the image should be assessed to evaluate a segmentation technique. The new evaluation method based on measurement of physical textured test objects was proposed. Firstly, a series of object images was obtained by the use of different devices (scanner, digital camera and TV camera). Secondly, the images were segmented using oscillator network and feedforward artificial neural

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

    DEFF Research Database (Denmark)

    Thomsen, Morten Bækgaard; Oros, Avram; Schoenmakers, Marieke; van Opstal, Jurren M; Maas, Joep N; Beekman, Jet D M; Vos, Marc A

    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 bradycardi...

  10. 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!

  11. Intracardiac thrombus in Behçet's disease: Two case reports

    Directory of Open Access Journals (Sweden)

    Brahem Radhia

    2005-07-01

    Full Text Available Abstract Intracardiac thrombus in Behçet's disease is an extremely rare manifestation. We report two such cases. A 20-year-old man presented with dyspnoea, cough and haemoptysis. Right heart thrombus associated with pulmonary artery aneurysm and thromboembolism was identified by helical CT and transoesophageal echocardiography. The second case was a 29-year-old male admitted for fever and chest pain. A diagnosis of right atrial thrombosis associated with pulmonary embolism and hyperhomocysteinemia was made. Due to the absence of haemodynamic compromise, medical management consisting of immunosupressive and anticoagulation therapy was adopted which resulted in complete dissolution of the thrombus with dramatic clinical improvement in both cases of clinical status. Conclusion intracardiac thrombus is a rare complication of Behçet's disease. As shown in our patients, medical treatment should be considered as the first line.

  12. 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.

  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. 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.

  16. 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.

  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. 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...

  19. 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

  20. 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

  1. Postural heart block.

    OpenAIRE

    Seda, P E; McAnulty, J H; Anderson, C J

    1980-01-01

    A patient presented with orthostatic dizziness and syncope caused by postural heart block. When the patient was supine, atrioventricular conduction was normal and he was asymptomatic; when he was standing he developed second degree type II block and symptoms. The left bundle-branch block on his electrocardiogram and intracardiac electrophysiological study findings suggest that this heart block occurred distal to the His bundle. Orthostatic symptoms are usually presumed to be secondary to an i...

  2. Intracardiac impedance as a method for ventricular volume monitoring - Investigation by a finite-element model and clinical data

    Science.gov (United States)

    Lippert, M.; Berdyshev, S.; Czygan, G.; Bocchiardo, M.; Hensel, B.

    2010-04-01

    A method for monitoring left ventricular (LV) volume changes of the human heart by intracardiac impedance measurement was developed. In order to model this method, we simulated the ventricular contraction using a finite-element model (FEM). The myocardium comprised three layers with anatomical fiber orientation. During excitation propagation contraction forces were applied, taking into account the myocardial elastic properties and the blood pressure time course. For a set of 21 contraction stages we calculated the intracardiac impedance Z between the right ventricular (RV) and LV leads for a set of common LV lead positions. The FEM results were compared to clinical data. Impedance and stroke volume were determined during overdrive pacing and end diastolic volume (EDV) at rest in 14 patients. All clinical EDV values were in the range of 147-394ml. Both the clinical data and the FEM in this volume range showed a linear correlation between admittance Y=1/Z and ventricular volume. For a quantitative comparison end diastolic impedance EDZ and the slope dY/dV were calculated. The model results across all LV lead positions were EDZ=0.16-1.2Ω, and dY/dV=3.3-21mS/ml, corresponding to clinical values of EDZ=0.14-1.46Ω and dY/dV=1-64mS/ml. In conclusion, the FEM resembled the clinical measurement data and serves as theoretical basis for ventricular volume monitoring via intracardiac impedance.

  3. Robust inter-beat interval estimation in cardiac vibration signals

    International Nuclear Information System (INIS)

    Reliable and accurate estimation of instantaneous frequencies of physiological rhythms, such as heart rate, is critical for many healthcare applications. Robust estimation is especially challenging when novel unobtrusive sensors are used for continuous health monitoring in uncontrolled environments, because these sensors can create significant amounts of potentially unreliable data. We propose a new flexible algorithm for the robust estimation of local (beat-to-beat) intervals from cardiac vibration signals, specifically ballistocardiograms (BCGs), recorded by an unobtrusive bed-mounted sensor. This sensor allows the measurement of motions of the body which are caused by cardiac activity. Our method requires neither a training phase nor any prior knowledge about the morphology of the heart beats in the analyzed waveforms. Instead, three short-time estimators are combined using a Bayesian approach to continuously estimate the inter-beat intervals. We have validated our method on over-night BCG recordings from 33 subjects (8 normal, 25 insomniacs). On this dataset, containing approximately one million heart beats, our method achieved a mean beat-to-beat interval error of 0.78% with a coverage of 72.69%. (paper)

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

    Directory of Open Access Journals (Sweden)

    Zdenka Křenová

    2013-03-01

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

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

    OpenAIRE

    A. Sarkar; Barat, P.

    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 ...

  6. 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.

  7. 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...

  8. 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

  9. 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

  10. 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...

  11. 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

    International Nuclear Information System (INIS)

    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.

  12. High Altitude and Intracardiac Devices(Pacemaker and Intracardiac Defibrillator andCardiac Resynchronisation Therapy)

    OpenAIRE

    Gürsoy, Mustafa Ozan; Yıldız, Banu Şahin; Yıldız, Mustafa

    2013-01-01

    Cardiovascular system responds to high altitude short after exposure. Hypoxia induces increase in heart rate, myocardial contractility, and cardiac output. This may have clinical implications in patients with underlying heart disease such as coronary artery disease, heart failure and rhythm disorders. Past studies have showed that patients may experience altitude-induced arrhythmias. However, there are conflicting data for patients with cardiac devices such as permanent pacemaker, intracardia...

  13. 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

  14. 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

  15. In vitro assessment of mitral valve function in cyclically pressurized porcine hearts.

    Science.gov (United States)

    Vismara, Riccardo; Leopaldi, Alberto M; Piola, Marco; Asselta, Chiara; Lemma, Massimo; Antona, Carlo; Redaelli, Alberto; van de Vosse, Frans; Rutten, Marcel; Fiore, Gianfranco B

    2016-04-01

    Recent approaches to the in vitro experimental study of cardiac fluid mechanics involve the use of whole biological structures to investigate in the lab novel therapeutic approaches for the treatment of heart pathologies. To enhance reliability and repeatability, the influence of the actuation strategy of the experimental apparatuses on the biomechanics of biological structures needs to be assessed. Using echography and intracardiac high-speed imaging, we compared the mitral valve (MV) anatomo-functional features (coaptation areas/lengths, papillary muscles-valvular plane distances) in two passive-beating-heart mock loops with internal (IPML) or external (EPML) pressurization of the ventricular chamber. Both apparatuses showed fluid dynamic conditions that closely resembled the physiology. The MVs analyzed in the EPML presented coaptation areas and lengths that were systematically higher, and exhibited greater variability from early-to peak-systole, as compared to those in the IPML. Moreover, in the EPML, the MV leaflets exhibited a convexity with high curvature toward the atrium. With the IPML, MV coaptation lengths ranged similar to available clinical data and the papillary muscles-valve plane distances were more stable throughout systole. In conclusion, both the apparatuses allow for reproducing in vitro the left heart hemodynamics, in terms of flow rates and pressures, with proper mitral valve continence. Results suggest that the IPML is more suitable for replicating the physiological MV functioning, while the EPML may have more potential as a model for the study of MV pathologies. PMID:26908180

  16. 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.

  17. 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:

  18. 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.

  19. 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.

  20. Optimal ciliary beating patterns

    Science.gov (United States)

    Vilfan, Andrej; Osterman, Natan

    2011-11-01

    We introduce a measure for energetic efficiency of single or collective biological cilia. We define the efficiency of a single cilium as Q2 / P , where Q is the volume flow rate of the pumped fluid and P is the dissipated power. For ciliary arrays, we define it as (ρQ) 2 / (ρP) , with ρ denoting the surface density of cilia. We then numerically determine the optimal beating patterns according to this criterion. For a single cilium optimization leads to curly, somewhat counterintuitive patterns. But when looking at a densely ciliated surface, the optimal patterns become remarkably similar to what is observed in microorganisms like Paramecium. The optimal beating pattern then consists of a fast effective stroke and a slow sweeping recovery stroke. Metachronal waves lead to a significantly higher efficiency than synchronous beating. Efficiency also increases with an increasing density of cilia up to the point where crowding becomes a problem. We finally relate the pumping efficiency of cilia to the swimming efficiency of a spherical microorganism and show that the experimentally estimated efficiency of Paramecium is surprisingly close to the theoretically possible optimum.

  1. 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

  2. The Role of Intracardiac Echocardiography in Atrial Fibrillation Ablation

    Directory of Open Access Journals (Sweden)

    Elad Anter, MD

    2009-10-01

    Full Text Available Radiofrequency catheter ablation of pulmonary veins has emerged as an effective therapy for patients with symptomatic atrial fibrillation. Advances in real-time intracardiac echocardiography with 2D and Doppler color flow imaging have led to it integration in atrial fibrillation ablation procedures. It allows imaging of the left atrium and pulmonary veins, including identification of anatomic variations. It has an important role in guiding transseptal catheterization, imaging the pulmonary vein ostia, assisting in accurate placement of mapping and ablation catheters, monitoring lesion morphology and flow changes in the ablated pulmonary veins, hence allowing titration of energy delivery. Importantly, it allows instant detection of procedural complications.

  3. The Role of Intracardiac Echocardiography in Atrial Fibrillation Ablation

    Directory of Open Access Journals (Sweden)

    Elad Anter

    2009-10-01

    Full Text Available Radiofrequency catheter ablation of pulmonary veins has emerged as an effective therapy for patients with symptomatic atrial fibrillation. Advances in real-time intracardiac echocardiography with 2D and Doppler color flow imaging have led to its integration in atrial fibrillation ablation procedures. It allows imaging of the left atrium and pulmonary veins, including identification of anatomic variations. It has an important role in guiding transseptal catheterization, imaging the pulmonary vein ostia, assisting in accurate placement of mapping and ablation catheters, monitoring lesion morphology and flow changes in the ablated pulmonary veins, hence allowing titration of energy delivery. Importantly, it allows instant detection of procedural complications.

  4. Intracardiac echocardiography to diagnose pannus formation after aortic valve replacement.

    Science.gov (United States)

    Yamamoto, Yoshiya; Ohara, Takahiro; Funada, Akira; Takahama, Hiroyuki; Amaki, Makoto; Hasegawa, Takuya; Sugano, Yasuo; Kanzaki, Hideaki; Anzai, Toshihisa

    2016-03-01

    A 66-year-old female, under regular follow-up for 20 years after aortic valve replacement (19-mm Carbomedics), presented dyspnea on effort and hypotension during hemodialysis. A transthoracic echocardiogram showed elevation of transvalvular velocity up to 4 m/s, but the structure around the aortic prosthesis was difficult to observe due to artifacts. Fluoroscopy revealed normal motion of the leaflets of the mechanical valve. Intracardiac echocardiography (ICE) revealed a pannus-like structure in the left ventricular outflow tract. Transesophageal echocardiogram also revealed this structure. ICE can visualize structural abnormalities around a prosthetic valve after cardiac surgery even in patients in whom conventional imaging modalities failed. PMID:26732266

  5. 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

  6. 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.

  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. 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...

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

    Science.gov (United States)

    de Almeida, Marcos Moura; Tavares, Wládia Gislaynne de Sousa; Furtado, Maria Mônica Alencar Araripe; Fontenele, Maria Marcia Farias Trajano

    2016-01-01

    Abstract Objective: To describe a case of neonatal atrial flutter after the insertion of an intracardiac umbilical venous catheter, reporting the clinical presentation and reviewing the literature on this subject. Case description: A late-preterm newborn, born at 35 weeks of gestational age to a diabetic mother and large for gestational age, with respiratory distress and rule-out sepsis, required an umbilical venous access. After the insertion of the umbilical venous catheter, the patient presented with tachycardia. Chest radiography showed that the catheter was placed in the position that corresponds to the left atrium, and traction was applied. The patient persisted with tachycardia, and an electrocardiogram showed atrial flutter. As the patient was hemodynamically unstable, electric cardioversion was successfully applied. Comments: The association between atrial arrhythmias and misplaced umbilical catheters has been described in the literature, but in this case, it is noteworthy that the patient was an infant born to a diabetic mother, which consists in another risk factor for heart arrhythmias. Isolated atrial flutter is a rare tachyarrhythmia in the neonatal period and its identification is essential to establish early treatment and prevent systemic complications and even death. PMID:26525686

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

    Science.gov (United States)

    Inafuku, Hitoshi; Nakamoto, Tomoko; Taira, Yusuke; Taira, Rie; Tsubakimoto, Maho; Totsuka, Yuichi; Kuniyoshi, Yukio; Tamaki, Tomoko; Aoyama, Hajime

    2016-01-01

    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.

  11. 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

  12. 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

  13. 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...

  14. 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...

  15. 24-hour electrocardiographic study of heart rate and rhythm patterns in population of healthy children.

    OpenAIRE

    Southall, D P; Johnston, F.; Shinebourne, E. A.; Johnston, P G

    1981-01-01

    Twenty-four hour electrocardiographic recordings were made on 104 randomly selected, healthy 7 to 11-year-old children. Ninety-two were technically adequate and suitable for analysis. The mean highest heart rate measured by direct electrocardiographic analysis over nine beats was 164 +/- 17. The mean lowest heart rates were 49 +/- 6 over three beats', and 56 +/- 6 over nine beats' duration. The maximum duration of heart rates less than 55/minute was 40 minutes. At their lowest heart rates 41 ...

  16. The Evolving Utility of Intracardiac Echocardiography in Cardiac Procedures

    Directory of Open Access Journals (Sweden)

    Dr. Christopher F. Liu

    2014-04-01

    Full Text Available Intracardiac echocardiography (ICE has gained increasing use in electrophysiology due to the need to visualize key anatomic structures. Precise guidance for transseptal puncture and visualization of the pulmonary veins are common essential uses for ICE, but many operators adept at ICE imaging have developed additional and specific uses. With heavy use of ICE guidance, electrophysiologists demonstrated feasibility of left atrial ablation with minimal use of fluoroscopy. With the advent of 3D mapping-integrated ICE, rendering of contours for the left atrium, aortic cusps, and left ventricular structures such as the papillary muscles have become possible. Improved understanding of the anatomy of these areas can facilitate mapping and ablation of these structurally complex sites. Additional uses of scar-visualization and integration into voltage maps have been explored. Left atrial appendage imaging has been an area of interest in the ICE community, although technological improvements are likely needed to make this more reliably complete. A new real-time 3D ICE catheter has also been developed, and work is in progress to delineate potential uses for this new frontier. Increasingly routine use of ICE has led to improved real-time guidance of all percutaneous cardiac procedures.

  17. GENERAL: Stochastic Alternating Dynamics for Synchronous EAD-Like Beating Rhythms in Cultured Cardiac Myocytes

    Science.gov (United States)

    Zhang, Ning; Zhang, Hui-Min; Liu, Zhi-Qiang; Ding, Xue-Li; Yang, Ming-Hao; Gu, Hua-Guang; Ren, Wei

    2009-11-01

    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.

  18. 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.

  19. 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

  20. A novel type of self-beating cardiomyocytes in adult mouse ventricles

    International Nuclear Information System (INIS)

    This study was designed to investigate the presence of resident heart cells that are distinct from terminally-differentiated cardiomyocytes. Adult mouse heart was coronary perfused with collagenase, and ventricles were excised and further digested. After spinning cardiomyocyte-containing fractions down, the supernatant fraction was collected and cultured without adding any chemicals. Two to five days after plating, some of rounded cells adhered to the culture dish, gradually changed their shape and then started self-beating. These self-beating cells did not appreciably proliferate but underwent a further morphological maturation process to form highly branched shapes with many projections. These cells were mostly multinucleated, well sarcomeric-organized and expressed cardiac marker proteins, defined as atypically-shaped cardiomyocytes (ACMs). Patch-clamp experiments revealed that ACMs exhibited spontaneous action potentials arising from the preceding slow diastolic depolarization. We thus found a novel type of resident heart cells in adult cardiac ventricles that spontaneously develop into self-beating cardiomyocytes.

  1. 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;…

  2. 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)

  3. 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.

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

    OpenAIRE

    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 ...

  5. 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)

  6. Beat-to-beat evaluation of left ventricular ejection in cardiac arrhythmias

    International Nuclear Information System (INIS)

    Conventional multi-gated cardiac blood pool studies suffer from two kinds of superimpositions: the spatial overlapping of various heart chambers and the temporal superimposition of a large number of cardiac cycles. The first problem can be partially solved by first pass techniques or by emission tomography. For the second one, which is specially critical arrhythmias, the single probe device (''nuclear stethoscope'') represents an original solution. Patients with normal cardiac rythm and patients presenting various kinds of cardiac rythm alterations were examined using a commercial ''nuclear stethoscope''. Some characteristic results achieved in these cases, were presented. For blood pool labeling, 20 mCi of 99mTc albumin was injected. The single probe detector was then positioned over the left ventricular area. The beat-to-beat left ventricular activity curve was then recorded for several minutes on paper in the same time as the E.C.G. signal. In cases with irregular cardiac rythm, the multigated techniques yield an average value of left ventricular ejection. Due to the relatively constant duration of systole, the superimposition of cycles may be valid during contration: differences mainly appear during diastole. But, as it could be demonstrated using the ''nuclear stethoscope'', individual cycles can show a large variability of ejection and average ejection fraction is only a very partial aspect of the real cardiac function

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

    Energy Technology Data Exchange (ETDEWEB)

    Takala, P. [Laboratory of Biomedical Engineering, Helsinki University of Technology, FIN-02015 HUT (Finland)]|[BioMag Laboratory, Medical Engineering Centre, Helsinki University Central Hospital, FIN-00029 HUCH (Finland). E-mail: panu.takala@hut.fi; Montonen, J.; Nenonen, J.; Katila, T. [Laboratory of Biomedical Engineering, Helsinki University of Technology, FIN-02015 HUT (Finland); BioMag Laboratory, Medical Engineering Centre, Helsinki University Central Hospital, FIN-00029 HUCH (Finland); Haenninen, H.; Maekijaervi, M.; Toivonen, L. [BioMag Laboratory, Medical Engineering Centre, Helsinki University Central Hospital, FIN-00029 HUCH (Finland); Division of Cardiology, Helsinki University Central Hospital, FIN-00029 HUCH (Finland)

    2001-04-01

    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)

  8. 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

  9. 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

  10. 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.

  11. 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.

  12. How to Take Your Heart Rate

    Science.gov (United States)

    ... beats per minute. - If you have difficulty with math, try doubling the number twice. 25 doubled is ... from going too high. If you are taking medicine for your heart or blood pressure, check with ...

  13. 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

  14. Losing the beat: deficits in temporal coordination.

    Science.gov (United States)

    Palmer, Caroline; Lidji, Pascale; Peretz, Isabelle

    2014-12-19

    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

  15. Heart rate variability and heart rate recovery as prognostic factors

    OpenAIRE

    2015-01-01

    Background and aim Heart rate (HR) can appear static and regular at rest, during exercise or recovery after exercise. However, HR is constantly adjusted due to factors such as breathing, blood pressure control, thermoregulation and the renin-angiotensin system, leading to a more dynamic response that can be quantified using HRV (heart rate variability). HRV is defined as the deviation in time between successive normal heart beat and is a noninvasive method to measure the total variation in a ...

  16. Computer analysis of radiocardiograms of patients with intracardiac shunts

    International Nuclear Information System (INIS)

    In 112 patients catheterized for congenital heart disease, radiocardiographic data have been collected by right atrial injection of sup(113m)In. Four scintillation detectors were used to monitor the activity changes in the heart, lungs and head. The heart measurements were done with both frontal and left lateral detectors, the latter being constructed for better collimation and efficiency. The CAMAC system and PDP-9 computer served for data collection, storage analysis, and display. Data were collected at 10 or 20 points per second and the pulsatile output of heart curves recorded. Since radiocardiograms in patients with shunts are complex, a computer program (PULSE) incorporating a pulsatile heart model was written for radiocardiogram simulation and analysis. The model consists of a series of compartments pulsating alternately. From each compartment a certain fraction of indicator is ejected into the next compartment and added to the indicator retained there. Each cardiac chamber is represented by one compartment, while pulmonary and systemic circulation are represented by a series of paired number of compartments. For shunt simulation a certain fraction can be ejected backward or forward along the series. In order to shorten the computation the model was fitted only to the end-diastolic and end-systolic states of the compartments. In left-to-right haemodynamically significant shunts the heart and lung curves show recirculation peaks. In right-to-left shunts the head curve detects the early arrival of indicator and shows a biphasic character. The addition of a computer for data acquisition and for pulsatile model simulation and analysis makes it possible to estimate shunt flows. Estimates correlate well with results of standard shunt measurements. (author)

  17. Intracardiac ECHO Integration with Three Dimensional Mapping: Role in AF Ablation

    Directory of Open Access Journals (Sweden)

    Yaariv Khaykin,MD

    2008-07-01

    Full Text Available Background Catheter ablation of atrial fibrillation (AF is typically guided by 3D mapping. This involves point-by-point reconstruction of the 3D virtual anatomy and may be time consuming and require substantial fluoroscopy exposure. Intracardiac echocardiography (ICE affords real time imaging of the cardiac structures during mapping and ablation. Methods Between February and May 2007, 15 patients (100% men, 10 with paroxysmal AF presenting for AF ablation were offered mapping using a novel system integrating 3D mapping and ICE. A modified ICE probe with a location sensor tracked by the mapping system was positioned in the right atrium (RA. This allowed acquisition of ECG gated images of the left atrium (LA. Endocardial contours were traced on each image and were used to generate a registered 3D map. Results 3D maps took a mean of 51+/-25 minutes to create, PRIOR to entering the LA and without fluoroscopy. Pulmonary veins and the esophagus were rendered in 3D. A complete map was built from a mean of 46+/-19 contours. Upon instrumentation of the left atrium, the maps were easily distorted if points collected by the mapping catheter were combined with the original map, due to deformation of the left atrial geometry by the relatively stiff ablation catheter. Pulmonary vein antrum isolation was guided by a circular mapping catheter. Since this catheter could not be visualized on the CARTO map, fluoroscopy was used to track its position and the contact between the ablation catheter and the circular mapping catheter. No substantial reduction in fluoroscopy time was thus realized, as expected. At 10+/-1 months of followup, 73% of the patients were in sinus rhythm after the initial three month blanking period. No patient suffered any complications related to the procedure or in follow-up. Conclusions A mapping system combining ICE and 3D electroanatomical mapping can feasibly reconstruct a 3D shell of the LA and the pulmonary veins without the need to

  18. Intracardiac ECHO Integration With Three Dimensional Mapping: Role in AF Ablation

    Directory of Open Access Journals (Sweden)

    Atul Verma

    2008-07-01

    Full Text Available Catheter ablation of atrial fibrillation (AF is typically guided by 3D mapping. This involves point-by-point reconstruction of the 3D virtual anatomy and may be time consuming and require substantial fluoroscopy exposure. Intracardiac echocardiography (ICE affords real time imaging of the cardiac structures during mapping and ablation. Methods: Between February and May 2007, 15 patients (100% men, 10 with paroxysmal AF presenting for AF ablation were offered mapping using a novel system integrating 3D mapping and ICE. A modified ICE probe with location sensor tracked by the mapping system was positioned in the right atrium (RA. This allowed acquisition of ECG gated images of the left atrium (LA. Endocardial contours were traced on each image and were used to generate a registered 3D map. Results: 3D maps took a mean of 51+/-25 minutes to create, PRIOR to entering the LA and without fluoroscopy. Pulmonary veins and the esophagus were rendered in 3D. A complete map was built from a mean of 46+/-19 contours. While the maps were precise prior to instrumentation of the left atrium, they were easily distorted if points collected by the mapping catheter were combined with the original map due to deformation of the left atrial geometry by the relatively stiff ablation catheter. Pulmonary vein antrum isolation was guided by a circular mapping catheter. Since this catheter could not be visualized on the CARTO map, fluoroscopy was used to track its position and the contact between the ablation catheter and the circular mapping catheter. No substantial reduction in fluoroscopy time was thus realized as expected. At 10+/-1 months of followup, 73% of the patients were in sinus rhythm after the initial three month blanking period. No patient suffered any complications related to the procedure or in follow-up. Conclusions: A mapping system combining ICE and 3D electroanatomical mapping can feasibly reconstruct a 3D shell of the LA and the pulmonary veins

  19. 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

  20. An alien in the heart

    Directory of Open Access Journals (Sweden)

    Yashwant Agrawal

    2016-07-01

    Full Text Available 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.

  1. Intravenous anaesthetics inhibit nicotinic acetylcholine receptor-mediated currents and Ca2+ transients in rat intracardiac ganglion neurons.

    Science.gov (United States)

    Weber, Martin; Motin, Leonid; Gaul, Simon; Beker, Friederike; Fink, Rainer H A; Adams, David J

    2005-01-01

    The effects of intravenous (i.v.) anaesthetics on nicotinic acetylcholine receptor (nAChR)-induced transients in intracellular free Ca(2+) concentration ([Ca(2+)](i)) and membrane currents were investigated in neonatal rat intracardiac neurons. In fura-2-loaded neurons, nAChR activation evoked a transient increase in [Ca(2+)](I), which was inhibited reversibly and selectively by clinically relevant concentrations of thiopental. The half-maximal concentration for thiopental inhibition of nAChR-induced [Ca(2+)](i) transients was 28 microM, close to the estimated clinical EC(50) (clinically relevant (half-maximal) effective concentration) of thiopental. In fura-2-loaded neurons, voltage clamped at -60 mV to eliminate any contribution of voltage-gated Ca(2+) channels, thiopental (25 microM) simultaneously inhibited nAChR-induced increases in [Ca(2+)](i) and peak current amplitudes. Thiopental inhibited nAChR-induced peak current amplitudes in dialysed whole-cell recordings by approximately 40% at -120, -80 and -40 mV holding potential, indicating that the inhibition is voltage independent. The barbiturate, pentobarbital and the dissociative anaesthetic, ketamine, used at clinical EC(50) were also shown to inhibit nAChR-induced increases in [Ca(2+)](i) by approximately 40%. Thiopental (25 muM) did not inhibit caffeine-, muscarine- or ATP-evoked increases in [Ca(2+)](i), indicating that inhibition of Ca(2+) release from internal stores via either ryanodine receptor or inositol-1,4,5-trisphosphate receptor channels is unlikely. Depolarization-activated Ca(2+) channel currents were unaffected in the presence of thiopental (25 microM), pentobarbital (50 microM) and ketamine (10 microM). In conclusion, i.v. anaesthetics inhibit nAChR-induced currents and [Ca(2+)](i) transients in intracardiac neurons by binding to nAChRs and thereby may contribute to changes in heart rate and cardiac output under clinical conditions. PMID:15644873

  2. 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...

  3. 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)

  4. 5 Ways to Beat Pre-performance Nerves

    Science.gov (United States)

    ... Who Cuts? 5 Ways to Beat Pre-performance Nerves KidsHealth > For Teens > 5 Ways to Beat Pre- ... nervios anticipatorios 5 Ways to Beat Pre-performance Nerves Lots of people stress out about talking in ...

  5. 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 ...

  6. 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

  7. 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...

  8. 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

  9. Intracardiac therapy following emergency thoracotomy in the accident and emergency department: an experimental model.

    OpenAIRE

    Moulton, C; Pennycook, A; Crawford, R

    1992-01-01

    For a select group of patients with penetrating chest trauma, immediate thoracotomy in the accident and emergency department offers the only chance of survival. Foley catheters have been used to achieve haemostasis in cardiac wounds but are not widely used for intracardiac fluid and drug administration during resuscitation. In an anatomical model designed to assess this procedure an average flow rate of 275 ml min-1 was achieved. The equipment required is readily available and easily assembled.

  10. 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

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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...

  16. 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, ...

  17. 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 ...

  18. Wearable Beat-to-Beat Blood Pressure Monitor

    Science.gov (United States)

    Lee, Yong Jin

    2015-01-01

    Linea Research Corporation has developed a wearable noninvasive monitor that provides continuous blood pressure and heart rate measurements in extreme environments. Designed to monitor the physiological effects of astronauts' prolonged exposure to reduced-gravity environments as well as the effectiveness of various countermeasures, the device offers wireless connectivity to allow transfer of both real-time and historical data. It can be modified to monitor the health status of astronaut crew members during extravehicular missions.

  19. 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 %.

  20. 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 ...

  1. 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...

  2. 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.

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

    Science.gov (United States)

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

    2007-03-01

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

  4. 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.

  5. Novel, single-beat approach for determining both end-systolic pressure–dimension relationship and preload recruitable stroke work

    Science.gov (United States)

    Inuzuka, Ryo; Kass, David A; Senzaki, Hideaki

    2016-01-01

    Objective The end-systolic pressure–dimension relationship (ESPDR) and the preload recruitable stroke work (PRSW) relationship are load-insensitive measures of contractility, but their clinical application has been limited by the need to record multiple beats over a wide volume range. In this study, we therefore sought to validate a new method to concomitantly determine the ESPDR and the PRSW relationship from a single beat. Methods Pressure–dimension loops were recorded in 14 conscious dogs under various haemodynamic and pathological conditions. Multiple-beat PRSW relationship was determined for its slope (Mw) and for a dimension-axis intercept (Dw). The ESPDR represented by the formula , was estimated from a steady-state, single-beat late-systolic pressure–dimension relationship. The single-beat Mw was determined as an end-systolic pressure when the end-systolic dimension was equal to Dw. Results A strong correlation was observed between multiple-beat and single-beat ESPDRs (zero-stress dimension; r=0.98, p<0.0001). The single-beat estimation of Mw calculated using the wall thickness was strongly correlated with the actual Mw (r=0.93, p<0.0001) and was sensitive enough to detect the change in contractility by dobutamine infusion (p<0.001) and by tachycardia-induced heart failure (p<0.001). Similar results were obtained for Mw estimated without information on wall thickness. Conclusions Mw can be interpreted as an end-systolic pressure when the end-systolic dimension is equal to Dw. By using the non-linear ESPDR, accurate single-beat estimation of the ESPDR and Mw is possible even without information on wall thickness. These results should enhance the applicability of pressure–volume framework to clinical medicine. PMID:27347424

  6. 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.

  7. Heart Health

    Science.gov (United States)

    ... Connected Home » Heart Health Heath and Aging Heart Health Your Heart Changes to Your Heart With ... are both taking steps toward heart health. Your Heart Your heart is a strong muscle about the ...

  8. 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).

  9. 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

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

    International Nuclear Information System (INIS)

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

  11. Muscarinic and nicotinic ACh receptor activation differentially mobilize Ca2+ in rat intracardiac ganglion neurons.

    Science.gov (United States)

    Beker, Friederike; Weber, Martin; Fink, Rainer H A; Adams, David J

    2003-09-01

    The origin of intracellular Ca2+ concentration ([Ca2+]i) transients stimulated by nicotinic (nAChR) and muscarinic (mAChR) receptor activation was investigated in fura-2-loaded neonatal rat intracardiac neurons. ACh evoked [Ca2+]i increases that were reduced to approximately 60% of control in the presence of either atropine (1 microM) or mecamylamine (3 microM) and to <20% in the presence of both antagonists. Removal of external Ca2+ reduced ACh-induced responses to 58% of control, which was unchanged in the presence of mecamylamine but reduced to 5% of control by atropine. The nAChR-induced [Ca2+]i response was reduced to 50% by 10 microM ryanodine, whereas the mAChR-induced response was unaffected by ryanodine, suggesting that Ca2+ release from ryanodine-sensitive Ca2+ stores may only contribute to the nAChR-induced [Ca2+]i responses. Perforated-patch whole cell recording at -60 mV shows that the rise in [Ca2+]i is concomitant with slow outward currents on mAChR activation and with rapid inward currents after nAChR activation. In conclusion, different signaling pathways mediate the rise in [Ca2+]i and membrane currents evoked by ACh binding to nicotinic and muscarinic receptors in rat intracardiac neurons. PMID:12761283

  12. 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 ± 5.5% of...

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

    International Nuclear Information System (INIS)

    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.

  14. 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

  15. 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.)

  16. 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 ...

  17. Acoustical sensing of cardiomyocyte cluster beating

    International Nuclear Information System (INIS)

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

  18. Entrapment of a Pacing Lead within a Chiari Network: Utility of Intracardiac Echo and a Laser Sheath.

    Science.gov (United States)

    Aung, Htin; Espinosa, Raul E; Powell, Brian D; McLeod, Christopher J

    2016-06-01

    Although rare, Chiari networks are elaborate embryological remnants that can pose distinct challenges for catheter and pacing lead manipulation within the right atrium. Device entrapment may require open thoracotomy for removal, with significant morbidity. We report an unusual case of pacing lead entanglement within this structure, followed by prompt intracardiac echocardiographic identification and laser sheath removal. PMID:26873294

  19. 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

  20. 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.

  1. 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. ...

  2. THz radiation by beating Langmuir waves

    CERN Document Server

    Son, S; Park, J Y

    2013-01-01

    An intense terahertz (THz) radiation generated by the beating of two Langmuir waves, which are excited by the forward Raman scattering, is analyzed theoretically. The radiation energy per shot can be as high as 0.1 J, with the duration of 10 pico-second. Appropriate plasma density and the laser characteristics are examined.

  3. 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.

  4. 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.

  5. Beat gestures modulate auditory integration in speech perception

    OpenAIRE

    Biau, Emmanuel; Soto-Faraco, Salvador, 1970-

    2013-01-01

    Spontaneous beat gestures are an integral part of the paralinguistic context during face-to-face conversations. Here we investigated the time course of beat-speech integration in speech perception by measuring ERPs evoked by words pronounced with or without an accompanying beat gesture, while participants watched a spoken discourse. Words accompanied by beats elicited a positive shift in ERPs at an early sensory stage (before 100 ms) and at a later time window coinciding with the auditory com...

  6. 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.

  7. 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...

  8. Beat Gestures Modulate Auditory Integration in Speech Perception

    Science.gov (United States)

    Biau, Emmanuel; Soto-Faraco, Salvador

    2013-01-01

    Spontaneous beat gestures are an integral part of the paralinguistic context during face-to-face conversations. Here we investigated the time course of beat-speech integration in speech perception by measuring ERPs evoked by words pronounced with or without an accompanying beat gesture, while participants watched a spoken discourse. Words…

  9. 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

  10. Detrended fluctuation analysis of non-stationary cardiac beat-to-beat interval of sick infants

    Science.gov (United States)

    Govindan, Rathinaswamy B.; Massaro, An N.; Al-Shargabi, Tareq; Niforatos Andescavage, Nickie; Chang, Taeun; Glass, Penny; du Plessis, Adre J.

    2014-11-01

    We performed detrended fluctuation analysis (DFA) of cardiac beat-to-beat intervals (RRis) collected from sick newborn infants over 1-4 day periods. We calculated four different metrics from the DFA fluctuation function: the DFA exponents αL (>40 beats up to one-fourth of the record length), αs (15-30 beats), root-mean-square (RMS) fluctuation on a short-time scale (20-50 beats), and RMS fluctuation on a long-time scale (110-150 beats). Except αL , all metrics clearly distinguished two groups of newborn infants (favourable vs. adverse) with well-characterized outcomes. However, the RMS fluctuations distinguished the two groups more consistently over time compared to αS . Furthermore, RMS distinguished the RRi of the two groups earlier compared to the DFA exponent. In all the three measures, the favourable outcome group displayed higher values, indicating a higher magnitude of (auto-)correlation and variability, thus normal physiology, compared to the adverse outcome group.

  11. 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.

  12. Detection of persistent ductus in hypoplastic left heart syndrome by contrast echocardiography.

    OpenAIRE

    Mortera, C; Leon, G.

    1980-01-01

    A patient with hypoplastic left heart syndrome was studied using contrast echocardiography after peripheral venous injection of dextrose. The combination of the parasternal and suprasternal approach allowed for identification of the right ventricular cavity, excluded the presence of right-to-left intracardiac shunts, and established normal ventriculoarterial connections. From the abdominal approach, the abdominal aorta was identified as an echo-free space corresponding to this structure in po...

  13. 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...

  14. 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

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

    Science.gov (United States)

    Stephens, Philip J.

    2015-01-01

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

  16. 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.

  17. 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

  18. Functional structural similarity between insect and human hearts: Electrocardiography of insect hearts for screening of new cardioactive drugs

    Czech Academy of Sciences Publication Activity Database

    Sláma, Karel; Aulický, R.; Lukáš, J.

    Bristol : IOP Publishing Ltd, 2013, s. 5-12. ISBN 978-989-8565-78-5. [Cardiotechnik 2013: International Congress on Cardiomuscular Technologies. Algarve (PT), 19.09.2013-21.09.2013] Grant ostatní: GA ČR(CZ) QJI310057 Institutional support: RVO:60077344 Keywords : peristaltic myocardial contractions * tubular heart * heart beat reversal Subject RIV: ED - Physiology

  19. Newborn infants detect the beat in music

    OpenAIRE

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

    2009-01-01

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

  20. 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 ...

  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 ... defects, or viral infections of the heart. Although heart transplant surgery is a life-saving measure, it has ...

  2. MR imaging of the heart: functional imaging

    International Nuclear Information System (INIS)

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

  3. 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

  4. 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.

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

    OpenAIRE

    Cho, Hyung JI; Jung, Jung Im; Kim, Hwan Wook; Lee, Kyo Young

    2012-01-01

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

  6. 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…

  7. 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...

  8. 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.

  9. Scale Invariant Properties in Heart Rate Signals

    International Nuclear Information System (INIS)

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

  10. An electric artificial heart for clinical use.

    Science.gov (United States)

    Pierce, W S; Rosenberg, G; Snyder, A J; Pae, W E; Donachy, J H; Waldhausen, J A

    1990-09-01

    Advances in microelectronics, high-strength magnets, and control system design now make replacement of the heart using an implantable, electrically powered pump feasible. The device described herein is a compact, dual pusher plate unit with valved polyurethane sac-type ventricles positioned at either end. The power unit consists of a small, brushless direct current motor and a motion translator. A microprocessor control system is used to regulate heart beat rate and provide left-right output balance. Bench studies lasting for as long as 1 year have been performed. Heart replacement with the electric heart has been performed in 18 calves since 1984. The longest survivor lived for more than 7 months. Among the causes of termination were component failure, thromboembolic complications, and bleeding. No major problem has been identified that precludes prolonged use of the electric heart. In the future the patient with end-stage heart disease will have an electric artificial heart as one therapeutic option. PMID:2396885

  11. 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...

  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

    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...... complexity. More recently, retrospective gating technologies were described (2; 3). In these studies, a time series of 2D images at several positions along the heart volume was used to produce a time sequence of 3D volumes of the beating heart. Rearrangement and validation of the asynchronously acquired...

  13. 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

  14. 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

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

    Directory of Open Access Journals (Sweden)

    Gottfried Schlaug

    2013-11-01

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

  16. 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

  17. 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.

  18. Inverse Problem for Color Doppler Ultrasound-Assisted Intracardiac Blood Flow Imaging

    Science.gov (United States)

    Jang, Jaeseong

    2016-01-01

    For the assessment of the left ventricle (LV), echocardiography has been widely used to visualize and quantify geometrical variations of LV. However, echocardiographic image itself is not sufficient to describe a swirling pattern which is a characteristic blood flow pattern inside LV without any treatment on the image. We propose a mathematical framework based on an inverse problem for three-dimensional (3D) LV blood flow reconstruction. The reconstruction model combines the incompressible Navier-Stokes equations with one-direction velocity component of the synthetic flow data (or color Doppler data) from the forward simulation (or measurement). Moreover, time-varying LV boundaries are extracted from the intensity data to determine boundary conditions of the reconstruction model. Forward simulations of intracardiac blood flow are performed using a fluid-structure interaction model in order to obtain synthetic flow data. The proposed model significantly reduces the local and global errors of the reconstructed flow fields. We demonstrate the feasibility and potential usefulness of the proposed reconstruction model in predicting dynamic swirling patterns inside the LV over a cardiac cycle. PMID:27313657

  19. 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

  20. 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.

  1. Analysis of Heart Rate Variability Using Time-Varying Filtering of Heart Transplanted Patients

    OpenAIRE

    Laouini, Ghailen; Meste, Olivier; Meo, Marianna

    2012-01-01

    In this paper, we analyze the heart rate variability (HRV), obtained by using the time-varying integral pulse frequency modulation (TVIPFM) which is well adapted to the exercise stress testing. We consider that the mean heart period is varying function of time, during exercise. This technique allows the estimation of the autonomic nervous system modulation (ANS) from the beat occurrences. The estimated respiratory sinus arrhythmia is then filtered in the time-frequency domain around the respi...

  2. 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 ...

  3. 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 ...

  4. Stark quantum beat spectroscopy of polyatomic molecules

    International Nuclear Information System (INIS)

    We derive analytical expressions for Stark quantum beat signals of polyatomic molecules and discuss them with regard to molecular and geometrical parameters. The general treatment is specified for near prolate asymmetric rotor molecules and a method for determining rotational constants and all components of the dipole moment of electronically excited polyatomic molecules is presented. The method is tested and illustrated for the vibrationless S1 state of deuterated propynal (HCtriple bondCCDO, Cs symmetry) and its lowest frequency non-totally symmetric state 121. The results of the vibrationless state are compared with structural data reported in the literature. For the 121 state we obtain A=1.5004(43) cm-1, B=0.16131(34) cm-1, C=0.14623(34) cm-1, and the components of the electric dipole moment in the molecular plane μa=-0.88(2) D, μb=1.03(2) D. Furthermore, it is shown that the modulation depth of Stark quantum beat signals can be utilized to quantify the contribution of the individual components of the transition moment to the total emission. (orig.)

  5. 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.

  6. Wearable sensor for heart rate detection

    Science.gov (United States)

    Shi, Cong; Liu, Xiaohua; Kong, Lingqin; Wu, Jizhe; Liu, Ming; Dong, Liquan; Hui, Mei; Zhao, Yuejin

    2015-08-01

    In recent years heart and blood vessel diseases kill more people than everything else combined. The daily test of heart rate for the prevention and treatment of the heart head blood-vessel disease has the vital significance. In order to adapt the transformation of medical model and solve the low accuracy problem of the traditional method of heart rate measuring, we present a new method to monitor heart rate in this paper. The heart rate detection is designed for daily heart rate detection .The heart rate signal is collected by the heart rate sensor. The signal through signal processing circuits converts into sine wave and square wave in turn. And then the signal is transmitted to the computer by data collection card. Finally, we use LABVIEW and MATLAB to show the heart rate wave and calculate the heart rate. By doing contrast experiment with medical heart rate product, experimental results show that the system can realize rapidly and accurately measure the heart rate value. A measurement can be completed within 10 seconds and the error is less than 3beat/min. And the result shows that the method in this paper has a strong anti-interference ability. It can effectively suppress the movement interference. Beyond that the result is insensitive to light.

  7. Video evaluation of the kinematics and dynamics of the beating cardiac syncytium: an alternative to the Langendorff method.

    Science.gov (United States)

    Fassina, Lorenzo; Di Grazia, Antonio; Naro, Fabio; Monaco, Lucia; De Angelis, Maria Gabriella Cusella; Magenes, Giovanni

    2011-07-01

    Many important observations and discoveries in heart physiology have been made possible using the isolated heart method of Langendorff. Nevertheless, the Langendorff method has some limitations and disadvantages such as the vulnerability of the excised heart to contusions and injuries, the probability of preconditioning during instrumentation, the possibility of inducing tissue edema, and high oxidative stress, leading to the deterioration of the contractile function. To avoid these drawbacks associated with the use of a whole heart, we alternatively used beating mouse cardiac syncytia cultured in vitro in order to assess possible ergotropic, chronotropic, and inotropic effects of drugs. To achieve this aim, we developed a method based on image processing analysis to evaluate the kinematics and the dynamics of the drug-stimulated beating syncytia starting from the video recording of their contraction movement. In this manner, in comparison with the physiological no-drug condition, we observed progressive positive ergotropic, positive chronotropic, and positive inotropic effects of 10 µM isoproterenol (ß-adrenergic agonist) and early positive ergotropic, negative chronotropic, and positive inotropic effects of 10 µM phenylephrine (alpha-adrenergic agonist), followed by a late phase with negative ergotropic, positive chronotropic, and negative inotropic trends. Our method permitted a systematic study of in vitro beating syncytia, producing results consistent with previous works. Consequently, it could be used in in vitro studies of beating cardiac patches, as an alternative to Langendorff's heart in biochemical and pharmacological studies, and especially when the Langendorff technique is inapplicable (e.g., in studies about human cardiac syncytium in physiological and pathological conditions, patient-tailored therapeutics, and syncytium models derived from induced pluripotent/embryonic stem cells with genetic mutations). Furthermore, the method could be helpful in

  8. Metal particulate matter components affect gene expression and beat frequency of neonatal rat ventricular myocytes.

    Science.gov (United States)

    Graff, Donald W; Cascio, Wayne E; Brackhan, Joseph A; Devlin, Robert B

    2004-05-01

    Soluble particulate matter (PM) components (e.g., metals) have the potential to be absorbed into the bloodstream and transported to the heart where they might induce the expression of inflammatory cytokines and remodel electrical properties. We exposed cultured rat ventricular myocytes to similar concentrations of two metals [zinc (Zn) and vanadium (V)] found commonly in PM and measured changes in spontaneous beat rate. We found statistically significant reductions in spontaneous beat rate after both short-term (4-hr) and long-term (24-hr) exposures, with a more substantial effect seen with Zn. We also measured the expression of genes associated with inflammation and a number of sarcolemmal proteins associated with electrical impulse conduction. Exposure to Zn or V (6.25-50 microM) for 6 hr produced significant increases in IL-6, IL-1 alpha, heat shock protein 70, and connexin 43 (Cx43). After 24 hr exposure, Zn induced significant changes in the gene expression of Kv4.2 and KvLQt (potassium channel proteins), the alpha 1 subunit of the L-type calcium channel, and Cx43, as well as IL-6 and IL-1 alpha. In contrast, V produced a greater effect on Cx43 and affected only one ion channel (KvLQT1). These results show that exposure of rat cardiac myocytes to noncytotoxic concentrations of Zn and V alter spontaneous beat rate as well as the expression of ion channels and sarcolemmal proteins relevant to electrical remodeling and slowing of spontaneous beat rate, with Zn producing a more profound effect. As such, these data suggest that the cardiac effects of PM are largely determined by the relative metal composition of particles. PMID:15159208

  9. 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.

  10. 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

  11. 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

  12. 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...

  13. 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.

  14. 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

    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...... group. All other electrophysiological parameters (RR, QT and MAP durations) were comparable for the two groups. Extending the number of animals and groups confirmed a larger BVR in the SCD group (SCD: 5.1 +/- 2.7; n = 11 versus control: 2.5 +/- 0.4 ms; n = 61; P <0.05) and showed reverse-use dependence...

  15. 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...

  16. Simple and Cost-effective Heart Rate Meter Using PIC Microcontroller

    OpenAIRE

    Souvik Das

    2014-01-01

    One of the major and significant physiological parameters of human cardiovascular system is the heart rate. Heart rate is represented by the number of times the heart beats per minute. The heart rate data can reflect various physiological states such as stress at work, concentration on tasks, drowsiness, biological workload, and the active state of the autonomic nervous system. Human cardiac dynamics are driven by the complex nonlinear interactions of two competing forces: sym...

  17. 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 ...

  18. Auxiliary total artificial heart: A compact electromechanical artificial heart working simultaneously with the natural heart.

    Science.gov (United States)

    Andrade, A; Nicolosi, D; Lucchi, J; Biscegli, J; Arruda, A C; Ohashi, Y; Mueller, J; Tayama, E; Glueck, J; Nosé, Y

    1999-09-01

    Leading international institutions are designing and developing various types of ventricular assist devices (VAD) and total artificial hearts (TAH). Some of the commercially available pulsatile VADs are not readily implantable into the thoracic cavity of smaller size patients because of size limitation. The majority of the TAH dimensions requires the removal of the patients' native heart. A miniaturized artificial heart, the auxiliary total artificial heart (ATAH), is being developed in these authors' laboratories. This device is an electromechanically driven ATAH using a brushless direct current (DC) motor fixed in a center metallic piece. This pusher plate-type ATAH control is based on Frank-Starling's law. The beating frequency is regulated through the change of the left preload, assisting the native heart in obtaining adequate blood flow. With the miniaturization of this pump, the average sized patient can have the surgical implantation procedure in the right thoracic cavity without removing the native heart. The left and right stroke volumes are 35 and 32 ml, respectively. In vitro tests were conducted, and the performance curves demonstrate that the ATAH produces 5 L/min of cardiac output at 180 bpm (10 mmHg of left inlet mean pressure and 100 mm Hg of left outlet mean pressure). Taking into account that this ATAH is working along with the native heart, this output is more than satisfactory for such a device. PMID:10491037

  19. Open heart surgery

    Science.gov (United States)

    ... Heart bypass surgery (coronary artery bypass graft - CABG) Heart transplant Heart valve surgery Hypoplastic left heart repair Minimally ... Heart bypass surgery Heart bypass surgery - minimally invasive Heart transplant Heart valve surgery Hypoplastic left heart syndrome Patent ...

  20. Energetics of synchronized states in three-dimensional beating flagella

    Science.gov (United States)

    Mettot, Clément; Lauga, Eric

    2011-12-01

    During collective locomotion, beating flagella of spermatozoa interact hydrodynamically and are observed experimentally to synchronize. G. I. Taylor used a small-amplitude two-dimensional sheet model to show that the rate at which swimmers do work against the fluid is minimal for in-phase beating. We use a semianalytical approach based on hydrodynamic reflections to extend these results to the small-amplitude three-dimensional beating of infinite flagellar filaments. We first consider a configuration of two parallel filaments. In the case where the beating of both flagella occurs in the same plane as that defined by their axis, in-phase beating is found to lead to an overall minimum of energy dissipation, while opposite-phase leads to a maximum. If we allow the orientation of the beating planes to vary, we find that the minimum of energy dissipation is obtained for either the in-phase or opposite-phase conformation, in a manner that depends on the flagella orientation and their relative distance. We further characterize numerically the set of optimal relative orientations. Quantitatively analogous results are obtained using a simple model based on the beating of two spheres interacting hydrodynamically in the far field. Exploiting the linearity of Stokes equation, we then extend our results to the case of three beating flagella in an aligned and triangular conformation. Consistent with Taylor’s two-dimensional work, our results suggest that, from a hydrodynamic standpoint, it is more energetically favorable for spermatozoa with three-dimensional flagella to swim close to each other and with synchronized, parallel, in-phase beating.

  1. 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 ...

  2. 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

  3. 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

  4. Quantum beats in fluorescence for multi-level atomic system

    International Nuclear Information System (INIS)

    For Λ-type three-level atomic systems we have clarified using diagram that (1) it is impossible to observe quantum beats due to the ground state sublevels by measuring the time dependence of the fluorescence intensity, and (2) why it is physically possible to observe and how we can observe quantum beats in the ground state sublevels by using fluorescence. Generalization of the results shows that we can determine from which state (the ground state or the excited state) the quantum beats are originated. Analytical result is shown for four-level atomic systems.

  5. Modulational instability in the beat-wave generation

    International Nuclear Information System (INIS)

    The coupling of a large amplitude plasmon, generated by the beat-wave process, to ion acoustic waves may lead to modulational or decay instabilities, which are investigated. A general dispersion relation obtainable from Zakharov equations predicts large growth rates (∼ ωsub(pi) for short wavelength modulations. To avoid these, extremely short pulse lengths are required in the beat-wave experiments. Due to the very long wavelength of the beat-plasmon, the decay instability is not likely below the keV-temperatures. (author)

  6. 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

  7. 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.

  8. Beating diffraction limit in an absorptive superlens

    Science.gov (United States)

    Xiao, Meng; Chan, Che Ting

    2013-03-01

    It is well known that a slab with both permittivity and permeability equals -1+i δ can achieve super resolution and its mechanism can be understood with the idea of complementary material. In practice, meta-materials are always absorptive and the absorption sets an upper limit for the image resolution. Here, we study the image formation of stratified complementary slabs in the time domain. Instead of only one slab of super lens, we consider a stack of AB structured complementary slabs, where A is a super lens and B is normal material. We show that the superlens stack can beat the diffraction limit even in the presence of loss if the source has a time-dependent intensity profile. We derived a general analytical expression for the group velocity of an arbitrary k component including evanescent waves near frequency where ``complementary'' is satisfied and the analytical results can explain the super solution in the presence of loss. And our results shows that, with a Gaussian shaped pulse illumination, the image resolution can be improved by about 45% relative to harmonic illumination for the same system.

  9. "'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.

  10. 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.

  11. 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.

  12. Design and evaluation of a handheld impedance plethysmograph for measuring heart rate variability

    DEFF Research Database (Denmark)

    Kristiansen, N. K.; Fleischer, J.; Jensen, M. S.;

    2005-01-01

    the reference method. Agreement between the two methods in measuring heart rate and root mean square of successive differences in the heart beat interval (RMSSD) was analysed using correlation coefficients (Pearson's R-2), mean differences with 95% confidence intervals and 95% limits of agreement, and...

  13. 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 th...

  14. 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.

  15. 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.

  16. Passive RFID tag based heart rate monitoring from an ECG signal.

    Science.gov (United States)

    Vora, Shrenik; Dandekar, Kapil; Kurzweg, Timothy

    2015-08-01

    In this paper, we propose a monitoring system that employs a passive RFID tag to transmit heart rate using an ECG signal as its source. This system operates without a battery and has been constructed with easily available commercial components. Here, an RFID tag is used as an on-off keying device, wherein it is normally transmitting, but turns off every time a heart beat is detected. Heart beats ranging from 30BPM through 300BPM are successfully measured using our device. It is shown that the system is capable of providing accurate heart rate measurements up to a distance of ten feet with a standard deviation of less than one beat per minute without a local power source. The proposed system is also found to be resilient in the presence of an additional RFID tag. PMID:26737271

  17. 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.

  18. 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.

  19. 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.

  20. Virtual histology of the human heart using optical coherence tomography

    Science.gov (United States)

    Ambrosi, Christina M.; Moazami, Nader; Rollins, Andrew M.; Efimov, Igor R.

    2009-09-01

    Optical coherence tomography (OCT) allows for the visualization of micron-scale structures within nontransparent biological tissues. For the first time, we demonstrate the use of OCT in identifying components of the cardiac conduction system and other structures in the explanted human heart. Reconstructions of cardiac structures up to 2 mm below the tissue surface were achieved and validated with Masson Trichrome histology in atrial, ventricular, sinoatrial nodal, and atrioventricular nodal preparations. The high spatial resolution of OCT provides visualization of cardiac fibers within the myocardium, as well as elements of the cardiac conduction system; however, a limiting factor remains its depth penetration, demonstrated to be ~2 mm in cardiac tissues. Despite its currently limited imaging depth, the use of OCT to identify the structural determinants of both normal and abnormal function in the intact human heart is critical in its development as a potential aid to intracardiac arrhythmia diagnosis and therapy.

  1. Cardiac CT angiography in children with congenital heart disease

    International Nuclear Information System (INIS)

    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

  2. Modeling of electrophysiology and tension development in the human heart

    OpenAIRE

    Seemann, Gunnar

    2005-01-01

    Comprehension of the beating of the human heart is important for cardiac research and will improve many clinical applications. Simulations based on models describing cardiac electro-mechanics can acquire insights into this behavior. This work focuses on the mathematical reconstruction of electrophysiology, excitation conduction, and tension development in the human heart on the cellular and the tissue level. The tissue models represent accurate anatomical shapes of the atria and the ventr...

  3. Heart Diseases

    Science.gov (United States)

    ... you'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. ... of disability. There are many different forms of heart disease. The most common cause of heart disease is ...

  4. 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 ...

  5. Heart Diseases

    Science.gov (United States)

    ... you're like most people, you think that heart disease is a problem for others. But heart disease is the number one killer in the ... of disability. There are many different forms of heart disease. The most common cause of heart disease ...

  6. 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.

  7. 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

  8. 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.)

  9. Heart Regeneration

    OpenAIRE

    Laflamme, Michael A.; Charles E. Murry

    2011-01-01

    Heart failure plagues industrialized nations, killing more people than any other disease. Heart failure usually results from a deficiency of cardiomyocytes, and a robust therapy to regenerate lost myocardium could help millions of patients a year. Heart regeneration is well documented in lower vertebrates and in developing mammals. After we are born, however, human heart regeneration becomes limited. In this article, Laflamme and Murry review the innate barriers to heart regeneration, the evi...

  10. 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

  11. 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.

  12. 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

  13. 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....

  14. Heart-pulse Biofeedback in Playful Exercise using a Wearable device and Modular Interactive Tiles

    DEFF Research Database (Denmark)

    Shimokakimoto, Tomoya; Lund, Henrik Hautop; Suzuki, Kenji

    2014-01-01

    interactive tiles. The system consists of a wearable device that measures heart-pulse via ear-mounted sensor, and modular interactive tiles which are used for physical rehabilitation exercise through playing a game. The wearable devise enables detection of heart pulse in real-time and therefore provides heart...... beat rate during playful activities, even if the heart pulse wave have motion artifacts. The tiles are designed to build flexible structures and to provide immediate feedback based on the users’ physical interaction with the tiles. We combine the two systems to provide users with heart pulse...... biofeedback in playful exercise. We show that using the developed system it is possible for the users to regulate the exercise intensity on their own with biofeedback, and also possible to analyze exercise activity using number of steps on the tiles and heart beat rate....

  15. 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 (<70 and ≥70 beats/min) and compared using generalized linear models specified with gamma error distributions and log links for 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

  16. Investigation of Bioinspired Gecko Fibers to Improve Adhesion of HeartLander Surgical Robot

    OpenAIRE

    Tortora, Giuseppe; Glass, Paul; Wood, Nathan; Aksak, Burak; Menciassi, Arianna; Sitti, Metin; Riviere, Cameron

    2012-01-01

    In this paper, a way for improving adhesion of a mobile robot (HeartLander) on biological tissue is presented, that integrates bioinspired gecko adhesive fibers on the robot surface. HeartLander is a medical robot proposed to perform clinical procedures on a beating heart, overcoming limitations of current cardiac procedures. Biologically inspired gecko fibers have been proposed for adhesion on surfaces. The aim of this work is to assess the advantages of integrating these structures for enha...

  17. 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 ...

  18. Heart MRI

    Science.gov (United States)

    ... you have: Brain aneurysm clips Certain types of artificial heart valves Heart defibrillator or pacemaker Inner ear (cochlear) implants Kidney disease or dialysis (you may not be able to ... artificial joints Certain types of vascular stents Worked with ...

  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 palpitations

    Science.gov (United States)

    Heart palpitations can be due to: Anxiety, stress, panic attack, or fear Caffeine intake Nicotine intake Cocaine or other illegal drugs Diet pills Exercise Fever However, some palpitations are due to an abnormal heart rhythm, ...

  1. 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.)

  2. 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 ...

  3. Molecular cardiology: the beat goes on

    International Nuclear Information System (INIS)

    Recombination DNA techniques have given cardiac physiologists their first access to the genes, proteins, and chemical signals that regulate the human heart. Scientists have been investigating the molecular biology of the angiotensinogen converting enzyme, renin, and of atrial natriuretic factor (ANF), an important cardiac-peptide hormone with a wide range of physiologic activities. Renin initiates a regulatory cascade that eventually produces angiotensin II, a potent hypertensive agent. By studying renin's genetic organization, and protein chemistry, scientists hope to be able to design a rational therapeutic to specifically inhibit this aspartyl protease. To determine if renin is endogenously produced or if it makes its way to these cells through the circulation. A combination of fluorescent-labeled antibodies and radio-labeled nucleic acid probes derived from renin cDNA were used

  4. 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...

  5. 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

  6. Exaggerated heart rate oscillations during two meditation techniques.

    Science.gov (United States)

    Peng, C K; Mietus, J E; Liu, Y; Khalsa, G; Douglas, P S; Benson, H; Goldberger, A L

    1999-07-31

    We report extremely prominent heart rate oscillations associated with slow breathing during specific traditional forms of Chinese Chi and Kundalini Yoga meditation techniques in healthy young adults. We applied both spectral analysis and a novel analytic technique based on the Hilbert transform to quantify these heart rate dynamics. The amplitude of these oscillations during meditation was significantly greater than in the pre-meditation control state and also in three non-meditation control groups: i) elite athletes during sleep, ii) healthy young adults during metronomic breathing, and iii) healthy young adults during spontaneous nocturnal breathing. This finding, along with the marked variability of the beat-to-beat heart rate dynamics during such profound meditative states, challenges the notion of meditation as only an autonomically quiescent state. PMID:10454297

  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. 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

  9. 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...

  10. 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.

  11. 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.

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

    DEFF Research Database (Denmark)

    Fox, Kim; Ford, Ian; Steg, Philippe Gabriel; Tardif, Jean-Claude; Tendera, Michal; Ferrari, Roberto; Jeppesen, Jørgen Lykke

    2014-01-01

    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...... those 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%, P<0.001). CONCLUSIONS: Among patients who had stable coronary artery disease without clinical heart failure, the addition of ivabradine to standard...

  13. 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

  14. 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

  15. 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

  16. Common multifractality in the heart rate variability and brain activity of healthy humans

    Science.gov (United States)

    Lin, D. C.; Sharif, A.

    2010-06-01

    The influence from the central nervous system on the human multifractal heart rate variability (HRV) is examined under the autonomic nervous system perturbation induced by the head-up-tilt body maneuver. We conducted the multifractal factorization analysis to factor out the common multifractal factor in the joint fluctuation of the beat-to-beat heart rate and electroencephalography data. Evidence of a central link in the multifractal HRV was found, where the transition towards increased (decreased) HRV multifractal complexity is associated with a stronger (weaker) multifractal correlation between the central and autonomic nervous systems.

  17. 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…

  18. 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

  19. Phase Shifting and the Beating of Complex Waves

    Science.gov (United States)

    Keeports, David

    2011-01-01

    At the introductory level, the demonstration and analysis of sound beating is usually limited to the superposition of two purely sinusoidal waves with equal amplitudes and very similar frequencies. Under such conditions, an observer hears the periodic variation of the loudness of a sound with an unchanging timbre. On the other hand, when complex…

  20. 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)

  1. 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)

  2. Beam cooling by using laser-undulator beat wave

    International Nuclear Information System (INIS)

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

  3. Testing the Beat Frequency Model of Horizontal Branch Qpos

    Science.gov (United States)

    Hertz, Paul

    The beat frequency modulated accretion (BFMA) model requires strong correlations in the horizontal branch quasiperiodic oscillations (HBO) and low frequency noise (LFN) amplitudes on time scales HBO and LFN amplitude predicted by the BFMA model and constrain some of the free observable parameters in the model. Any HBO model must account for these properties.

  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. 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...

  7. 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...

  8. Pharmacoeconomic analysis of heart rate slowing drugs in patients with ischemic heart disease

    Directory of Open Access Journals (Sweden)

    E. I. Tarlovskaya

    2016-03-01

    Full Text Available Aim. To compare the efficacy and cost/effectiveness ratio of the original and generic bisoprolol in achieving target heart rate (HR in patients with ischemic heart disease.Material and methods. Patients with ischemic heart disease (n=60; 36 males and 24 females aged from 35 to 75 years were included into the study. Patients were randomized into group A (received therapy based on the original bisoprolol or into group B (received therapy based on of generic bisoprolol. Ivabradine was added, if the effect was insufficient. The duration of follow-up was 6 weeks. The HR dynamics was assessed during the study period. Cost/effectiveness ratio was calculated.Results. Significant HR slowing was found in both groups by the end of observation. In group A baseline HR was 70.0±5.6 beats/min and in 6 weeks - 58.1±3.8 beats/min, while in group B - 69.5±5.2 and 60.5±3.9 beats/min respectively. HR slowing was significantly higher in group A than that in group B. Direct costs in order to achieve a target HR in 1 patient for 6 weeks of therapy in group A were 663.75 rubles, while this in group B - 1093.58 rubles. Direct costs for HR deceleration by 1 beat in group A were 48.46 rubles vs 69.40 rubles in group B. The effect of therapy based on the original bisoprolol, is superior to that when generic bisoprolol used.Conclusion. HR-slowing effect of therapy based on the original bisoprolol was superior to that when generic bisoprolol was used. Pharmacoeconomic analysis revealed that HR deceleration was more economically profitable in treatment based on the original bisoprolol.

  9. Automated tissue classification of intracardiac optical coherence tomography images (Conference Presentation)

    Science.gov (United States)

    Gan, Yu; Tsay, David; Amir, Syed B.; Marboe, Charles C.; Hendon, Christine P.

    2016-03-01

    Remodeling of the myocardium is associated with increased risk of arrhythmia and heart failure. Our objective is to automatically identify regions of fibrotic myocardium, dense collagen, and adipose tissue, which can serve as a way to guide radiofrequency ablation therapy or endomyocardial biopsies. Using computer vision and machine learning, we present an automated algorithm to classify tissue compositions from cardiac optical coherence tomography (OCT) images. Three dimensional OCT volumes were obtained from 15 human hearts ex vivo within 48 hours of donor death (source, NDRI). We first segmented B-scans using a graph searching method. We estimated the boundary of each region by minimizing a cost function, which consisted of intensity, gradient, and contour smoothness. Then, features, including texture analysis, optical properties, and statistics of high moments, were extracted. We used a statistical model, relevance vector machine, and trained this model with abovementioned features to classify tissue compositions. To validate our method, we applied our algorithm to 77 volumes. The datasets for validation were manually segmented and classified by two investigators who were blind to our algorithm results and identified the tissues based on trichrome histology and pathology. The difference between automated and manual segmentation was 51.78 +/- 50.96 μm. Experiments showed that the attenuation coefficients of dense collagen were significantly different from other tissue types (P < 0.05, ANOVA). Importantly, myocardial fibrosis tissues were different from normal myocardium in entropy and kurtosis. The tissue types were classified with an accuracy of 84%. The results show good agreements with histology.

  10. 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.

  11. 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 age and was higher in women than men (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.

  12. 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 ...

  13. 76 FR 14737 - Bureau of Educational and Cultural Affairs (ECA) Request for Grant Proposals: One Beat

    Science.gov (United States)

    2011-03-17

    ... of Educational and Cultural Affairs (ECA) Request for Grant Proposals: One Beat Announcement Type... opportunities. One Beat is a programmatic refinement of the existing Fiscal Year 2010 Cultural Visitors program..., professional enrichment, and artistic production. By concentrating on music, One Beat seeks to combine...

  14. Poor synchronization to the beat may result from deficient auditory-motor mapping.

    Science.gov (United States)

    Sowiński, Jakub; Dalla Bella, Simone

    2013-08-01

    Moving to the beat of music is natural and spontaneous for humans. Yet some individuals, so-called 'beat deaf', may differ from the majority by being unable to synchronize their movements to musical beat. This condition was recently described in Mathieu (Phillips-Silver et al. (2011). Neuropsychologia, 49, 961-969), a beat-deaf individual, showing inaccurate motor synchronization to the beat accompanied by poor beat perception, with spared pitch processing. It has been suggested that beat deafness is the outcome of impoverished beat perception. Deficient synchronization to the beat, however, may also result from inaccurate mapping of the perceived beat to movement. To test this possibility, we asked 99 non-musicians to synchronize with musical and non-musical stimuli via hand tapping. Ten among them who revealed particularly poor synchronization were submitted to a thorough assessment of motor synchronization to various pacing stimuli and of beat perception. Four participants showed poor synchronization in absence of poor pitch perception; moreover, among them, two individuals were unable to synchronize to music, in spite of unimpaired detection of small durational deviations in musical and non-musical sequences, and normal rhythm discrimination. This mismatch of perception and action points toward disrupted auditory-motor mapping as the key impairment accounting for poor synchronization to the beat. PMID:23838002

  15. 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- ...

  16. 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

  17. 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

  18. Fetal echocardiographic characteristics of fused heart in thoracopagus conjoined twins.

    Science.gov (United States)

    Wu, Yu; Lv, Qing; Xie, Ming-Xing; Wan, Lin-Yuan; Ren, Ping-Ping; Ge, Andrew; Ge, Shuping

    2014-08-01

    Conjoined twins (CT) are rare with possible serious malformations in which soft tissue, bone, or some organs are joined in utero. The extent of cardiac fusion and intracardiac anatomy of CT determine the viability, natural history, and outcome of potential surgical intervention. Early prenatal diagnosis and assessment may provide a window of opportunity to counsel the family for their informed decision on the pregnancy and to plan for prenatal and perinatal care. In this report, we describe a case of thoracopagus twins diagnosed by fetal echocardiography at 23-week gestation. The 2 hearts fused at the atrial and ventricular levels. The outcome and review of literature on fetal echocardiographic characteristics of this malformation are discussed. PMID:24814222

  19. 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 ...

  20. 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

  1. 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

  2. [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

  3. 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.

  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. 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...

  6. 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 (Pequestrian 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. PMID:23380228

  7. Mathematical Modeling of Flow Characteristics in the Embryonic Chick Heart

    DEFF Research Database (Denmark)

    Heebøll-Christensen, Jesper

    modified inertia, and resistance due to friction and curvature of the multilayered tubular heart. Through the modeling, flow conditions in the embryonic heart are characterized. The models suggest that eccentric rather than concentric deformation of the beating heart is optimal for mean flows induced by...... the Liebau effect. Additionally the elliptic cross-sectional shape of the embryonic heart may be optimally configured for Liebau induced flow near elliptic eccentricity 0.4. It is furthermore suggested that both peristaltic and Liebau induced pumping effectsmay be present in the embryonic heart......, though the models are not conclusive on this point. In addition the Liebau effect is investigated in a simpler system containing two elastic tubes joined to form a liquid filled ring, with a compression pump at an asymmetric location. Through comparison to other reports the system validates model...

  8. Elucidating the turbulence nature of the intracardiac flow: from medical images to multi-cycle Large Eddy Simulations

    OpenAIRE

    Chnafa, Christophe; Mendez, Simon; Nicoud, Franck

    2013-01-01

    This brief article accompanies a fluid dynamics video presenting the results of a large-eddy simulation of the flow in a realistic left heart. The left heart geometry, from the pulmonary veins to the aortic root, is extracted from medical images and the endocardium movements are reconstructed through image registration. Large-eddy simulations are thus performed in a patient-specific heart model, where the patient-specific movements of the geometry are prescribed. The flow obtained is intermit...

  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. Finding the ciliary beating pattern with optimal efficiency

    CERN Document Server

    Osterman, Natan

    2011-01-01

    We introduce a measure for energetic efficiency of biological cilia acting individually or collectively and numerically determine the optimal beating patterns according to this criterion. Maximizing the efficiency of a single cilium leads to curly, often symmetric and somewhat counterintuitive patterns. But when looking at a densely ciliated surface, the optimal patterns become remarkably similar to what is observed in microorganisms like Paramecium. The optimal beating pattern then consists of a fast effective stroke and a slow sweeping recovery stroke. Metachronal coordination is essential for efficient pumping and the highest efficiency is achieved with antiplectic waves. Efficiency also increases with an increasing density of cilia up to the point where crowding becomes a problem. We finally relate the pumping efficiency of cilia to the swimming efficiency of a spherical microorganism and show that the experimentally estimated efficiency of Paramecium is surprisingly close to the theoretically possible op...

  11. 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.

  12. Does Corporate Governance Matter in Meeting and Beating Analysts’ Forecasts

    OpenAIRE

    Soumaya Ben Malek Maztoul

    2014-01-01

    Meeting and beating analysts’ forecast has received substantial attention, most of studies investigate twoprinciples problems: the valuation and value relevance of meeting and tools used to achieve benchmarks. Thisresearch is different, we investigate whether internal corporate governance impacts on meeting and beatinganalysts’ forecasts and consistently do it, we also examine if these attributes alleviate opportunistic behavior.This paper contributes to the growing literature on earnings ben...

  13. 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...

  14. Coordinated Beating of Algal Flagella is Mediated by Basal Coupling

    OpenAIRE

    Wan, Kirsty Y.; Goldstein, Raymond E.

    2015-01-01

    In a great many of the contexts in which groups of cilia or flagella are found they exhibit synchronized behavior. This includes phase-locking, as seen in $Chlamydomonas$ flagella, and metachronal wave formation in the ciliary arrays of $Paramecium$ or in the respiratory cilia of higher organisms. Since the observations by Gray and Rothschild of phase synchrony of nearby swimming spermatozoa, it has been a working hypothesis that synchrony arises from hydrodynamic interactions between beating...

  15. 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...

  16. Beat-Event Detection in Action Movie Franchises

    OpenAIRE

    Potapov, Danila; Douze, Matthijs; Revaud, Jerome; Harchaoui, Zaid; Schmid, Cordelia

    2015-01-01

    While important advances were recently made towards temporally localizing and recognizing specific human actions or activities in videos, efficient detection and classification of long video chunks belonging to semantically defined categories such as "pursuit" or "romance" remains challenging.We introduce a new dataset, Action Movie Franchises, consisting of a collection of Hollywood action movie franchises. We define 11 non-exclusive semantic categories - called beat-categories - that are br...

  17. 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

  18. 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

  19. Effect of pre operative heart rate on post spinal hypotension in obsteric patients

    International Nuclear Information System (INIS)

    The purpose of the study was to determine the association between of preoperative heart rate and post spinal hypotension in women undergoing cesarean section, Two hundred patients undergoing caesarean were included in the study selected on non probability convenience sampling technique, The patients were divided into two groups depending upon their pre operative heart rate. Spinal anesthesia was administered and number of patients developing hypotension was noted. Among 200 patients, who were included in the study; 112 were placed in group A and 88 were placed in group B depending on mean heart rate of 90 beats per minute or less or 91 beats per minute or more respectively. In group A 14 (11.86%) patients developed hypotension where as in group B 28 (31,82%) patients developed hypotension. Pre operative heart rate is significantly associated with post spinal hypotension in obstetric patients undergoing cesarean section. (author)

  20. 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)

  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. 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

  3. 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...

  4. 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%.

  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. Feeling the pulse of Public Perception of Science: does Research make our hearts beat faster?

    OpenAIRE

    Locritani, Marina; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Batzu, Ilenia; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Carmisciano, Cosmo; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Muccini, Filippo; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Talamoni, Roberta; CSSN; La Tassa, Hebert; CSSN; Stroobant, Mascha; DLTM; Guccinelli, Giacomo; Steamfactory; Benvenuti, Lucrezia; Steamfactory; Abbate, Marinella; ENEA; Furia, Stefania; ENEA; Benedetti, Alessandro; CNR-IENI; Bernardini, Maria Ines; Liceo Scientifico Pacinotti; Centi, Roberto; Liceo Scientifico Pacinotti; Casale, Laura; Istituto Superiore Fossati – Da Passano

    2015-01-01

    In 2007 the Italian Ministry of Education identified the need of raising a new Humanism: students must receive adequate tools for knowledge, but must also understand and be able to handle the increasingly frequent transitions and changes they have to face as citizens and individuals. Orientation during the developmental phase must, hence, allow students to acquire all those key and context-independent competences, necessary for self-assessment of natural attitudes. Nevert...

  7. 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...

  8. Ca channel kinetics during the spontaneous heart beat in embryonic chick ventricle cells.

    OpenAIRE

    Risso, S.; DeFelice, L. J.

    1993-01-01

    The ability of Ca ions to inhibit Ca channels presents one of the most intriguing problems in membrane biophysics. Because of this negative feedback, Ca channels can regulate the current that flows through them. The kinetics of the channels depend on voltage, and, because the voltage controls the current, a strong interaction exists between voltage dependence and Ca dependence. In addition to this interaction, the proximity of pores and the local concentration of ions also determine how effec...

  9. A novel approach for the averaging of magnetocardiographically recorded heart beats

    Energy Technology Data Exchange (ETDEWEB)

    DiPietroPaolo, D [Advanced Technologies Biomagnetics, Pescara (Italy); Mueller, H-P [Division for Biosignals and Imaging Technologies, Central Institute for Biomedical Engineering, Ulm University, D-89069 Ulm (Germany); Erne, S N [Division for Biosignals and Imaging Technologies, Central Institute for Biomedical Engineering, Ulm University, D-89069 Ulm (Germany)

    2005-05-21

    Performing signal averaging in an efficient and correct way is indispensable since it is a prerequisite for a broad variety of magnetocardiographic (MCG) analysis methods. One of the most common procedures for performing the signal averaging to increase the signal-to-noise ratio (SNR) in magnetocardiography, as well as in electrocardiography (ECG), is done by means of spatial or temporal techniques. In this paper, an improvement of the temporal averaging method is presented. In order to obtain an accurate signal detection, temporal alignment methods and objective classification criteria are developed. The processing technique based on hierarchical clustering is introduced to take into account the non-stationarity of the noise and, to some extent, the biological variability of the signals reaching the optimum SNR. The method implemented is especially designed to run fast and does not require any interaction from the operator. The averaging procedure described in this work is applied to the averaging of MCG data as an example, but with its intrinsic properties it can also be applied to the averaging of ECG recording, averaging of body-surface-potential mapping (BSPM) and averaging of magnetoencephalographic (MEG) or electroencephalographic (EEG) signals.

  10. "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…

  11. Mimo pillow--an intelligent cushion designed with maternal heart beat vibrations for comforting newborn infants.

    Science.gov (United States)

    Chen, Wei; Oetomo, Sidarto Bambang; Tetteroo, Daniel; Versteegh, Frank; Mamagkaki, Thelxi; Pereira, Mariana Serras; Janssen, Lindy; van Meurs, Andrea

    2015-05-01

    Premature infants are subject to numerous interventions ranging from a simple diaper change to surgery while residing in neonatal intensive care units. These neonates often suffer from pain, distress, and discomfort during the first weeks of their lives. Although pharmacological pain treatment often is available, it cannot always be applied to relieve a neonate from pain or discomfort. This paper describes a nonpharmacological solution, called Mimo, which provides comfort through mediation of a parent's physiological features to the distressed neonate via an intelligent pillow system embedded with sensing and actuating functions. We present the design, the implementation, and the evaluation of the prototype. Clinical tests at Máxima Medical Center in the Netherlands show that among the nine of ten infants who showed discomfort following diaper change, a shorter recovery time to baseline skin conductance analgesimeter values could be measured when the maternal heartbeat vibration in the Mimo was switched ON and in seven of these ten a shorter crying time was measured. PMID:25148673

  12. 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...

  13. Heart Beat Characterization from Ballistocardiogram Signals using Extended Functions of Multiple Instances

    OpenAIRE

    Jiao, Changzhe; Lyons, Princess; Zare, Alina; Rosales, Licet; Skubic, Marjorie

    2016-01-01

    A multiple instance learning (MIL) method, extended Function of Multiple Instances ($e$FUMI), is applied to ballistocardiogram (BCG) signals produced by a hydraulic bed sensor. The goal of this approach is to learn a personalized heartbeat "concept" for an individual. This heartbeat concept is a prototype (or "signature") that characterizes the heartbeat pattern for an individual in ballistocardiogram data. The $e$FUMI method models the problem of learning a heartbeat concept from a BCG signa...

  14. 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 disease ...

  15. 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 ...

  16. Wine and heart health

    Science.gov (United States)

    Health and wine; Wine and heart disease; Preventing heart disease - wine; Preventing heart disease - alcohol ... more often just to lower your risk of heart disease. Heavier drinking can harm the heart and ...

  17. 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 ...

  18. 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 ...

  19. 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...

  20. Defining asymmetry in heart rate variability signals using a Poincaré plot

    International Nuclear Information System (INIS)

    The asymmetry in heart rate variability is a visibly obvious phenomenon in the Poincaré plot of normal sinus rhythm. It shows the unevenness in the distribution of points above and below the line of identity, which indicates instantaneous changes in the beat to beat heart rate. The major limitation of the existing asymmetry definition is that it considers only the instantaneous changes in the beat to beat heart rate rather than the pattern (increase/decrease). In this paper, a novel definition of asymmetry is proposed considering the geometry of a 2D Poincaré plot. Based on the proposed definition, traditional asymmetry indices—Guzik's index (GI), Porta's index (PI) and Ehlers' index (EI)—have been redefined. In order to compare the effectiveness of the new definition, all indices have been calculated for RR interval series of 54 subjects with normal sinus rhythm of 5 min and 30 min duration. The new definition resulted in a higher prevalence of normal subjects showing asymmetry in heart rate variability

  1. Evaluation of the influence of change in heart rate on left ventricular diastolic function indices

    International Nuclear Information System (INIS)

    In order to assess the influence of change in heart rate on left ventricular diastolic function indices, ECG gated cardiac pool study was performed in 6 patients with implanted programmable AAI pacemakers. Heart rate was changed by atrial pacing from 50 to 120 beats/min, every 10 beats/min. The filling fraction during first third of diastole (1/3FF), the peak filling rate (PFR), mean first third filling rate (1/3FR-mean) and early filling volume ratio (%EFV), being used as the indices of left ventricular diastolic performance, were assessed. In accordance with increase in heart rate, 1/3FF decreased significantly. PFR were fairly stable from 50 to 80 beats/min, but increased significantly from 90 to 120 beats/min. 1/3FR-mean and %EFV did not change significantly, but 1/3FR-mean showed decreasing tendency and %EFV showed increasing tendency as the heart rate was increased. %EFV was more changeable index than other indices among clinical cases. These results indicate that PFR and 1/3FR-mean were appropriate diastolic phase indices at rest. (author)

  2. 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

  3. Reduction of ciliary beat frequency in vitro by sputum from patients with bronchiectasis: a serine proteinase effect.

    OpenAIRE

    Smallman, L A; Hill, S. L.; Stockley, R A

    1984-01-01

    We have examined the effect of adding elastase positive sputum from six patients with purulent bronchiectasis on the ciliary beat frequency of nasal epithelium from normal subjects. Control studies of cilia suspended in tissue culture medium showed little change in ciliary beat frequency over six hours. Cilia incubated in elastase positive secretions, however, showed a considerable decrease in ciliary beat frequency over the period, falling from a mean of 13 X 40 beats/second to 6 X 78 beats/...

  4. The effect of competition on heart rate during kart driving: A field study

    Directory of Open Access Journals (Sweden)

    Yamakoshi Takehiro

    2011-09-01

    Full Text Available Abstract Background Both the act of competing, which can create a kind of mental stress, and participation in motor sports, which induces physical stress from intense g-forces, are known to increase heart rate dramatically. However, little is known about the specific effect of competition on heart rate during motor sports, particularly during four-wheel car driving. The goal of this preliminary study, therefore, was to investigate whether competition increases heart rate under such situations. Findings The participants drove an entry-level formula kart during two competitive races and during solo driving against the clock while heart rate and g-forces were measured. Analyses showed that heart rate values during the races (168.8 beats/min were significantly higher than those during solo driving (140.9 beats/min and rest (75.1 beats/min. Conclusions The results of this preliminary study indicate that competition heightens heart rate during four-wheel car driving. Kart drivers should be concerned about maintaining good health and developing physical strength.

  5. 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...

  6. 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)

  7. Elucidating the turbulence nature of the intracardiac flow: from medical images to multi-cycle Large Eddy Simulations

    CERN Document Server

    Chnafa, Christophe; Nicoud, Franck

    2013-01-01

    This brief article accompanies a fluid dynamics video presenting the results of a large-eddy simulation of the flow in a realistic left heart. The left heart geometry, from the pulmonary veins to the aortic root, is extracted from medical images and the endocardium movements are reconstructed through image registration. Large-eddy simulations are thus performed in a patient-specific heart model, where the patient-specific movements of the geometry are prescribed. The flow obtained is intermittent, showing both in the left atrium and in the left ventricle turbulent spots correlated to flow decelerations.

  8. 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....

  9. Roles of the creatine kinase system and myoglobin in maintaining energetic state in the working heart

    Directory of Open Access Journals (Sweden)

    Beard Daniel A

    2009-02-01

    Full Text Available Abstract Background The heart is capable of maintaining contractile function despite a transient decrease in blood flow and increase in cardiac ATP demand during systole. This study analyzes a previously developed model of cardiac energetics and oxygen transport to understand the roles of the creatine kinase system and myoglobin in maintaining the ATP hydrolysis potential during beat-to-beat transient changes in blood flow and ATP hydrolysis rate. Results The theoretical investigation demonstrates that elimination of myoglobin only slightly increases the predicted range of oscillation of cardiac oxygenation level during beat-to-beat transients in blood flow and ATP utilization. In silico elimination of myoglobin has almost no impact on the cytoplasmic ATP hydrolysis potential (ΔGATPase. In contrast, disabling the creatine kinase system results in considerable oscillations of cytoplasmic ADP and ATP levels and seriously deteriorates the stability of ΔGATPase in the beating heart. Conclusion The CK system stabilizes ΔGATPase by both buffering ATP and ADP concentrations and enhancing the feedback signal of inorganic phosphate in regulating mitochondrial oxidative phosphorylation.

  10. 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...

  11. Intermittency in Human Heart Rate Variability

    International Nuclear Information System (INIS)

    Intermittency in time series of the time intervals between heart beats (RR intervals) extracted from 24 hour (portable) ECG is found for some cases of humans with arrhythmia. Laminar phases are found by sweeping a short (5 intervals) time window through the time series and calculating the standard deviation of the series in each window. 8 of the 18 arrhythmia cases studied had a bimodal distribution of the standard deviation values indicating some kind of intermittency. The distribution of lengths of the laminar phases identifies the intermittency obtained in human heart rate variability as Type 1 in the Pomeau and Manneville classification. Although the arrhythmia cases studied were medically very different - in those instances that intermittency did occur the probability distributions of laminar phase lengths were strikingly similar. (author)

  12. Arrhythmia susceptibility in senescent rat hearts

    Directory of Open Access Journals (Sweden)

    Stefano Rossi

    2014-01-01

    Full Text Available Cardiovascular disease increases with age as well as alterations of cardiac electrophysiological properties, but a detailed knowledge about changes in cardiac electrophysiology relevant to arrhythmogenesis in the elderly is relatively lacking. The aim of this study was to determine specific age-related changes in electrophysiological properties of the ventricles which can be related to a structural-functional arrhythmogenic substrate. Multiple epicardial electrograms were recorded on the ventricular surface of in vivo control and aged rats, while arrhythmia vulnerability was investigated by premature stimulation protocols. Single or multiple ectopic beats and sustained ventricular arrhythmias were frequently induced in aged but not in control hearts. Abnormal ventricular activation patterns during sinus rhythm and unchanged conduction velocity during point stimulation in aged hearts suggest the occurrence of impaired impulse conduction through the distal Purkinje system that might create a potential reentry substrate.

  13. Cardiac mast cells regulate myocyte ANP release via histamine H2 receptor in beating rabbit atria.

    Science.gov (United States)

    Li, Dan; Wen, Jin Fu; Jin, Jing Yu; Quan, He Xiu; Cho, Kyung Woo

    2009-06-01

    It has been shown that histamine inhibits atrial natriuretic peptide (ANP) release. Because cardiac mast cells are the principal source of histamine in the heart, we hypothesized that cardiac mast cells are involved in the regulation of atrial ANP release. To test the hypothesis, experiments were performed in perfused beating rabbit atria allowing atrial pacing and measurements of changes in atrial stroke volume, intraatrial pulse pressure and myocyte ANP release. Mast cell degranulation with Compound 48/80 decreased atrial myocyte ANP release, and the response was blocked by a selective histamine H(2) receptor blocker, cimetidine, indicating that histamine was responsible for the decrease in ANP release. Mast cell stabilization with cromolyn blocked the Compound 48/80-induced decrease in ANP release. These data suggest that mast cell-derived histamine is involved in the regulation of cardiac ANP release. Thus, the cardiac mast cell-cardiomyocyte communication via the histamine-ANP pathway may implicate in the cardiac disorder associated with mast cell degranulation such as in acute coronary syndrome or cardiac hypertrophy. PMID:19328828

  14. 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.

  15. 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

  16. A High-Density EEG Investigation into Steady State Binaural Beat Stimulation

    OpenAIRE

    Goodin, Peter; Ciorciari, Joseph; Baker, Kate; Carrey, Anne-Marie; Harper, Michelle; Kaufman, Jordy

    2012-01-01

    Binaural beats are an auditory phenomenon that has been suggested to alter physiological and cognitive processes including vigilance and brainwave entrainment. Some personality traits measured by the NEO Five Factor Model have been found to alter entrainment using pulsing light stimuli, but as yet no studies have examined if this occurs using steady state presentation of binaural beats for a relatively short presentation of two minutes. This study aimed to examine if binaural beat stimulation...

  17. 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...

  18. 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.

  19. Beating of Coupled Ultraviolet Light Modes in Zinc Oxide Nanoresonators

    Science.gov (United States)

    Schirra, M.; Feneberg, M.; Prinz, G. M.; Reiser, A.; Röder, T.; Thonke, K.; Sauer, R.

    2009-02-01

    Periodic spatial intensity modulations of near-band-gap luminescence light at 3.36 eV photon energy are reported in nanometer-sized resonators of single zinc oxide nanorods. These modulations are observed when the luminescence light, due to excitonic recombination, is excited by a focused low-energy electron beam scanned along the rods. The acceleration energy of only 2 keV allows for a spatial resolution of a few ten nanometers. Numerical calculations based on the theory of dielectric cylindrical waveguides are performed identifying the intensity modulations as beating patterns of coupled TE01 and TM01 modes in the nanoresonator.

  20. Modulation of attosecond beating by resonant two-photon transition

    CERN Document Server

    Galán, Álvaro Jiménez; Martín, Fernando

    2015-01-01

    We present an analytical model that characterizes two-photon transitions in the presence of autoionising states. We applied this model to interpret resonant RABITT spectra, and show that, as a harmonic traverses a resonance, the phase of the sideband beating significantly varies with photon energy. This phase variation is generally very different from the $\\pi$ jump observed in previous works, in which the direct path contribution was negligible. We illustrate the possible phase profiles arising in resonant two-photon transitions with an intuitive geometrical representation.

  1. Modulation of Attosecond Beating by Resonant Two-Photon Transition

    Science.gov (United States)

    Jiménez Galán, Álvaro; Argenti, Luca; Martín, Fernando

    2015-09-01

    We present an analytical model that characterizes two-photon transitions in the presence of autoionising states. We applied this model to interpret resonant RABITT spectra, and show that, as a harmonic traverses a resonance, the phase of the sideband beating significantly varies with photon energy. This phase variation is generally very different from the π jump observed in previous works, in which the direct path contribution was negligible. We illustrate the possible phase profiles arising in resonant two-photon transitions with an intuitive geometrical representation.

  2. 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.

  3. Run to the Beat: Sport and music for the masses

    OpenAIRE

    Karageorghis, CI

    2013-01-01

    Run to the Beat is a half marathon event that is accompanied by live and pre-recorded music. The author was involved with the event as the lead consultant in the period 2007-2010. This case study examines the genesis of the event, the science on which it was predicated and how it was received by participating runners and the media. The primary driver for the event was the 2007 ban on personal listening devices by the International Amateur Athletics Federation, which outraged recreational runn...

  4. Digital Processing of Beat Note Signals from Optical Frequency Synthesizers

    Czech Academy of Sciences Publication Activity Database

    Čížek, Martin; Šmíd, Radek; Buchta, Zdeněk; Lazar, Josef; Číp, Ondřej

    Gothenburg: Chalmers University of Technology, 2012, s. 409-411. [European frequency and time forum 2012. Gothenburg (SE), 23.04.2012-27.04.2012] R&D Projects: GA ČR GPP102/11/P819; GA ČR GAP102/10/1813; GA ČR(CZ) GPP102/12/P962; GA MŠk ED0017/01/01; GA MŠk(CZ) LC06007 Institutional support: RVO:68081731 Keywords : digital processing of beat note signals * femtosecond optical frequency comb * digital servo-loop techniques * digital signal processing Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  5. 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.

  6. 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

  7. 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.

  8. 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

  9. 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

  10. Imaging of ischemic heart disease

    International Nuclear Information System (INIS)

    Despite advances in the understanding and treatment of ischemic cardiomyopathy, characterized by extensive coronary artery disease and left ventricular (LV) dysfunction, the prognosis remains poor with only a 50-60% 5-year survival rate. The composition of atherosclerotic lesions is currently regarded as being more important than the degree of stenosis in determining acute events. If imaging techniques could distinguish vulnerable from stable plaques, then high-risk patient subgroups could be identified. Another important concept is that LV dysfunction may be the result of either scarring due to necrosis or to the presence of myocardial hibernation, in which there is sufficient blood flow to sustain viable myocytes, but insufficient to maintain systolic contraction. This concept of myocardial viability is critical for making optimal clinical management decisions. This review describes how noninvasive imaging methods can be used to distinguish regions of irreversibly injured myocardium from viable but hibernating segments. Technical advances in CT and MR have made imaging of the beating heart possible. Considerable clinical progress has already been made and further cardiac applications are expected. Radiologists therefore have new opportunities for involvement in cardiac imaging but must recognize the political implications as well as the diagnostic potential of these modalities not only for the heart, but also for the whole vascular system. This review focuses on imaging myocardial injury. It compares state-of-the-art CT and MR with more established yet contemporary echocardiography and nuclear scintigraphy. (orig.)

  11. 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

  12. 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.

  13. 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

  14. 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

  15. 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.

  16. Conjoined hearts.

    OpenAIRE

    Antonelli, D.; Shmilovitz, L; Dharan, M

    1986-01-01

    Thoracopagus twins were delivered at 37 weeks' gestation by caesarean section. Respiratory distress was present and mechanical ventilation was needed; 36 hours after delivery severe lactic acidosis developed and the twins died. The pericardial sac was common and the hearts were conjoined as a single structure with ventricular fusion.

  17. Women's Heart Disease: Heart Attack Symptoms

    Science.gov (United States)

    ... this page please turn JavaScript on. Feature: Women's Heart Disease Heart Attack Symptoms Past Issues / Winter 2014 Table ... NHLBI has uncovered some of the causes of heart diseases and conditions, as well as ways to prevent ...

  18. Women's Heart Disease: Heart Disease Risk Factors

    Science.gov (United States)

    ... this page please turn JavaScript on. Feature: Women's Heart Disease Heart Disease Risk Factors Past Issues / Winter 2014 Table of ... or habits may raise your risk for coronary heart disease (CHD). These conditions are known as risk factors. ...

  19. 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 ...

  20. 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) ...

  1. Chaotic data analysis of heart R-R interval EKG data

    International Nuclear Information System (INIS)

    Cardiac beat-to-beat interval data is analyzed with a chaotic data analysis toolkit. The embedding dimension of ten data sets from healthy subjects is 7 or at most 8. Ten of the eleven pathological data sets have an embedding dimension of 9 or greater. Statistically, the first local minimum of average mutual information for healthy hearts is larger than the pathological cases. But, there is a large standard deviation for this metric that blurs the distinction between the healthy and pathological data. copyright 1996 American Institute of Physics

  2. 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

  3. 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

  4. 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.

  5. 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.

  6. 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 ...

  7. 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 ...

  8. 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 ...

  9. 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 ...

  10. 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 becomes ...

  11. 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 ...

  12. Structure of the Heart

    Science.gov (United States)

    ... Modules Resources Archived Modules Updates Structure of the Heart The human heart is a four-chambered muscular ... serous membrane forms the epicardium. Layers of the Heart Wall Three layers of tissue form the heart ...

  13. 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 ...

  14. Effects of thyroid state on respiration of perfused rat and guinea pig hearts

    International Nuclear Information System (INIS)

    The effects of thyroid state on the respiration of the isolated heart were investigated using retrograde perfused rat and guinea pig hearts. In both species, hypothyroidism caused a marked depression in circulating thyroid hormone concentrations and in the respiration of the isolated, retrograde perfused heart. Hypothyroidism was caused by injecting animals with Na131I. The effects on myocardial respiration could be attributed to changes in the contraction frequency and in the oxygen consumption per beat, with little contribution from basal respiration. Treatment of animals with thyroxine elevated plasma thyroid hormones to a similar extent in rats and guinea pigs. In the latter, thyroxine treatment was associated with substantial increases in the contraction frequency and the oxygen consumption per beat of the isolated heart. In contrast, only small changes were apparent in the retrograde perfused rat heart, observations that were confirmed in rat hearts perfused at near physiological work loads. It was concluded that rat hearts isolated from normal animals function at near maximal thyroid state, in contrast to the guinea pig heart, which requires higher circulating concentrations of thyroid hormones to attain maximal responses

  15. 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.

  16. 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 ...

  17. 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...

  18. Beat sampling accuracy in estimating spruce spider mite (Acari: Tetranychidae) populations and injury on juniper.

    Science.gov (United States)

    Shrewsbury, Paula M; Hardin, Mark R

    2004-08-01

    The use of a standardized beat sampling method for estimating spruce spider mite, Oligonychus ununguis (Jacobi) (Acari: Tetranychidae), densities on a widely used evergreen ornamental plant species, Juniperus chinensis variety 'Sargentii' A. Henry (Cupressaceae), was examined. There was a significant positive relationship between total spruce spider mite densities and spider mite densities from beat sampling on juniper. The slope and intercept of the relationship may be used by pest managers to predict total spider mite densities on plants from beat sample counts. Beat sampling dramatically underestimates the total number of spider mites on a foliage sample. The relationships between spruce spider mite feeding injury and spider mite density estimates from beat sampling juniper foliage and total spider mite counts on foliage were also examined. There was a significant positive relationship between spruce spider mite density as estimated from beat sampling and injury to the plants. There was a similar positive relationship between the total number of spruce spider mites and injury to the plants, suggesting that a pest manager could use beat sampling counts to estimate plant injury and related thresholds. These findings have important implications to decision-making for spruce spider mite control, especially as it relates to threshold levels and determining rates of predator releases. Further assessment of the effectiveness of beat and other sampling methods across multiple spider mite- host plant associations needs to be examined to enable pest managers to select sampling plans that are feasible and reliable. PMID:15384359

  19. 77 FR 17060 - Announcement of Requirements and Registration for Beat Down Blood Pressure Challenge

    Science.gov (United States)

    2012-03-23

    ... HUMAN SERVICES Announcement of Requirements and Registration for Beat Down Blood Pressure Challenge... years, announces the launch of the Beat Down Blood Pressure Video Challenge. This challenge is an open... consumer e-health tools to manage high blood pressure. Health care providers are also encouraged to...

  20. 77 FR 19015 - Announcement of Requirements and Registration for Beat Down Blood Pressure Challenge

    Science.gov (United States)

    2012-03-29

    ... HUMAN SERVICES Announcement of Requirements and Registration for Beat Down Blood Pressure Challenge... Health and Human Services (HHS) published a notice in the Federal Register (77 FR 17060) announcing requirements and registration for a Beat Down Blood Pressure Video Challenge. This challenge will not be...

  1. 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

  2. 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.

  3. 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.

  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. 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

  7. 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.

  8. 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

  9. 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 ...

  10. 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.

  11. Amusic does not mean unmusical: beat perception and synchronization ability despite pitch deafness.

    Science.gov (United States)

    Phillips-Silver, Jessica; Toiviainen, Petri; Gosselin, Nathalie; Peretz, Isabelle

    2013-01-01

    Pitch deafness, the most commonly known form of congenital amusia, refers to a severe deficit in musical pitch processing (i.e., melody discrimination and recognition) that can leave time processing--including rhythm, metre, and "feeling the beat"--preserved. In Experiment 1, we show that by presenting musical excerpts in nonpitched drum timbres, rather than pitched piano tones, amusics show normal metre recognition. Experiment 2 reveals that body movement influences amusics' interpretation of the beat of an ambiguous drum rhythm. Experiment 3 and a subsequent exploratory study show an ability to synchronize movement to the beat of popular dance music and potential for improvement when given a modest amount of practice. Together the present results are consistent with the idea that rhythm and beat processing are spared in pitch deafness--that is, being pitch-deaf does not mean one is beat-deaf. In the context of drum music especially, amusics can be musical. PMID:24344816

  12. 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.

  13. 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...

  14. Impact Analysis of Narrow Loom Beat-up Mechanism

    Directory of Open Access Journals (Sweden)

    Nurudeen A. Raji

    2011-09-01

    Full Text Available The study considers the impulse-momentum method for the analysis of the narrow loom with impulsive force and discontinuous velocities. The system equation of motion is analyzed to determine the main body velocities used for the system variables without introducing rotational coordinates or the turning effect of the system follower on the beater. Discontinuities in the velocity are observed when an impact force results from the beat-up action of the beater on the weft-yarn. Formulation between the velocity jump and displacement is presented for the system response. The impact phenomenon is characterized by the rise in the system velocity resulting from the vibration propagation through the system. The velocity is observed to increase as the system displacement response increases. This is typical of a high speed mechanism of this type mostly used in the textile industry if not controlled.

  15. Involvement of the autonomic nervous system in Chagas heart disease

    Directory of Open Access Journals (Sweden)

    Edison Reis Lopes

    1983-12-01

    Full Text Available The autonomic nervous system and especially the intracardiac autonomic nervous system is involved in Chagas' disease. Ganglionitis and periganglionitis were noted in three groups ofpatients dying with Chagas'disease: 1 Those in heart failure; 2 Those dying a sudden, non violent death and; 3 Those dying as a consequence ofaccidents or homicide. Hearts in the threegroups also revealed myocarditis and scattered involvement of intramyocardial ganglion cells as well as lesions of myelinic and unmyelinic fibers ascribable to Chagas'disease. In mice with experimentally induced Chagas' disease weobserved more intensive neuronal lesions of the cardiac ganglia in the acute phase of infection. Perhaps neuronal loss has a role in the pathogenesis of Chagas cardiomyopathy. However based on our own experience and on other data from the literature we conclude that the loss of neurones is not the main factor responsible for the manifestations exhibited by chronic chagasic patients. On the other hand the neuronal lesions may have played a role in the sudden death ofone group of patients with Chagas'disease but is difficult to explain the group of patients who did not die sudderly but instead progressed to cardiac failure.

  16. 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

  17. Retrieval of an intra-cardiac embolised very long wire via transhepatic access from a war victim child.

    Science.gov (United States)

    Baspinar, Osman; Sahin, Derya A; Yildirim, Ali

    2016-04-01

    We present the case report of a war victim child with severe burn scars, orthopnoea, and dyspnoea due to diffuse pulmonary thromboembolism. During ICU stay, a central venous catheter's 45-mm wire embolised into the heart. The embolised wire was successfully removed via transhepatic access through the creation of an artificial simple snare. PMID:26358097

  18. 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...

  19. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Firth, B.G.; Dehmer, G.J.; Markham, R.V. Jr.; Willerson, J.T.; Hillis, L.D.

    1982-11-01

    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.

  1. 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

  2. [Heart transplantation].

    Science.gov (United States)

    Fukushima, Norihide; Matsuda, Hikaru

    2005-11-01

    While nearly 4,000 patients undergo heart transplantation (HTx) every year in the world, only 27 HTx were performed since February, 1999, because of very strict Organ Transplantation Law in Japan. All were treated with triple immunosuppressive regimen. Although two patients died of infection 4 months and 4 years after HTx, respectively, 23 were discharged and 16 returned to work or go to school. New immunosuppressive drugs, such as sirolimus and everolimus, treatment of presensitized patients before transplantation using cyclophosphamide and intravenous globulin infusion, compact implantable left ventricular assist supports and the future of pediatric HTx in Japan are discussed. PMID:16277260

  3. 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....

  4. Revealing Hearts

    DEFF Research Database (Denmark)

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

    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....

  5. AN INTELLIGENT FUZZY BASED SCHEME TO ANALYZE HEART DISEASES

    Directory of Open Access Journals (Sweden)

    Neeru Anand

    2012-09-01

    Full Text Available The main objective of this research work is to define some fuzzy based ruleset to identify the patient disease based on person medical related information. This information includes the person age, calestrol level, heart beat and blood pressure. In this work these four characters of a patient are studied and presented in theform of fuzzy rule. As the fuzzy rule is applied on these characteristics collectively and based on it the decision about the heart disease is taken. Any of the medical diagnostic application cannot return true results; there are always some chances of perception while dealing with medical area. Even though theyobtained results shows that effective use of application for the initial prediction of heart disease based on user characteristics.

  6. 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.

  7. Heart rate and estimated energy expenditure of flapping and gliding in black-browed albatrosses.

    Science.gov (United States)

    Sakamoto, Kentaro Q; Takahashi, Akinori; Iwata, Takashi; Yamamoto, Takashi; Yamamoto, Maki; Trathan, Philip N

    2013-08-15

    Albatrosses are known to expend only a small amount of energy during flight. The low energy cost of albatross flight has been attributed to energy-efficient gliding (soaring) with sporadic flapping, although little is known about how much time and energy albatrosses expend in flapping versus gliding during cruising flight. Here, we examined the heart rates (used as an instantaneous index of energy expenditure) and flapping activities of free-ranging black-browed albatrosses (Thalassarche melanophrys) to estimate the energy cost of flapping as well as time spent in flapping activities. The heart rate of albatrosses during flight (144 beats min(-1)) was similar to that while sitting on the water (150 beats min(-1)). In contrast, heart rate was much higher during takeoff and landing (ca. 200 beats min(-1)). Heart rate during cruising flight was linearly correlated with the number of wing flaps per minute, suggesting an extra energy burden of flapping. Albatrosses spend only 4.6±1.4% of their time flapping during cruising flight, which was significantly lower than during and shortly after takeoff (9.8±3.5%). Flapping activity, which amounted to just 4.6% of the time in flight, accounted for 13.3% of the total energy expenditure during cruising flight. These results support the idea that albatrosses achieve energy-efficient flight by reducing the time spent in flapping activity, which is associated with high energy expenditure. PMID:23661772

  8. Human fetal cardiac progenitors: The role of stem cells and progenitors in the fetal and adult heart.

    Science.gov (United States)

    Bulatovic, Ivana; Månsson-Broberg, Agneta; Sylvén, Christer; Grinnemo, Karl-Henrik

    2016-02-01

    The human fetal heart is formed early during embryogenesis as a result of cell migrations, differentiation, and formative blood flow. It begins to beat around gestation day 22. Progenitor cells are derived from mesoderm (endocardium and myocardium), proepicardium (epicardium and coronary vessels), and neural crest (heart valves, outflow tract septation, and parasympathetic innervation). A variety of molecular disturbances in the factors regulating the specification and differentiation of these cells can cause congenital heart disease. This review explores the contribution of different cardiac progenitors to the embryonic heart development; the pathways and transcription factors guiding their expansion, migration, and functional differentiation; and the endogenous regenerative capacity of the adult heart including the plasticity of cardiomyocytes. Unfolding these mechanisms will become the basis for understanding the dynamics of specific congenital heart disease as well as a means to develop therapy for fetal as well as postnatal cardiac defects and heart failure. PMID:26421632

  9. Disentangling beat perception from sequential learning and examining the influence of attention and musical abilities on ERP responses to rhythm.

    Science.gov (United States)

    Bouwer, Fleur L; Werner, Carola M; Knetemann, Myrthe; Honing, Henkjan

    2016-05-01

    Beat perception is the ability to perceive temporal regularity in musical rhythm. When a beat is perceived, predictions about upcoming events can be generated. These predictions can influence processing of subsequent rhythmic events. However, statistical learning of the order of sounds in a sequence can also affect processing of rhythmic events and must be differentiated from beat perception. In the current study, using EEG, we examined the effects of attention and musical abilities on beat perception. To ensure we measured beat perception and not absolute perception of temporal intervals, we used alternating loud and soft tones to create a rhythm with two hierarchical metrical levels. To control for sequential learning of the order of the different sounds, we used temporally regular (isochronous) and jittered rhythmic sequences. The order of sounds was identical in both conditions, but only the regular condition allowed for the perception of a beat. Unexpected intensity decrements were introduced on the beat and offbeat. In the regular condition, both beat perception and sequential learning were expected to enhance detection of these deviants on the beat. In the jittered condition, only sequential learning was expected to affect processing of the deviants. ERP responses to deviants were larger on the beat than offbeat in both conditions. Importantly, this difference was larger in the regular condition than in the jittered condition, suggesting that beat perception influenced responses to rhythmic events in addition to sequential learning. The influence of beat perception was present both with and without attention directed at the rhythm. Moreover, beat perception as measured with ERPs correlated with musical abilities, but only when attention was directed at the stimuli. Our study shows that beat perception is possible when attention is not directed at a rhythm. In addition, our results suggest that attention may mediate the influence of musical abilities on beat

  10. 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.

  11. Wing-beat coupling between flying locust pairs: preferred phase and lift enhancement

    Science.gov (United States)

    Camhi; Sumbre; Wendler

    1995-01-01

    Pairs of locusts flying in tandem in a wind tunnel are known to couple their wing-beats intermittently. The rhythmically oscillating air flow from the front locust's wing-beat, detected by the rear individual, appears to convey the timing information for coupling. Three predictions of this arrangement were tested quantitatively in this study. (1) Given that the oscillating air flow has a wavelength of 7.5 cm, placing the rear locust 7.5 or 15 cm behind the front one should produce the same phase of coupling, whereas placing it at an intermediate distance of 11 cm should produce an opposite phase. (2) At any distance, the preferred phase at which wing-beat coupling occurs should depend, in part, on the difference in the wing-beat frequencies of the two locusts just before the coupling began. (3) At the moment that the wing-beats of the two locusts become coupled, a change should be observed consistently in the wing-beat frequency of the rear individual only. Each of these three predictions was fulfilled. We also recorded the instantaneous lift of the rear locust by tethering it to a laser torque meter. Lift varied with the phase of the wing-beats between the two locusts. For a given distance between the two locusts, lift was greater by a mean of 16 % of the locust's body mass at those phases where coupling most commonly occurred than at opposite phases. This lift effect was seen even if the wing-beats of the two locusts drifted through these preferred phases without actually coupling. These results are discussed in terms of a possible energetic advantage conferred to the rear locust by flying in tandem and by coupling its flight rhythm to the leader's wing-beat. PMID:9318863

  12. 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

  13. 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 ...

  14. Quantum beat and entanglement of multi-qubits interacting with a common reservoir

    International Nuclear Information System (INIS)

    The qubits can be entangled when they interact with a common Ohmic reservoir. We analyze how the reservoir-induced entanglement of qubits can be observed as the beat signal in the decay curve of the macroscopic polarization. The origin of this effect is the Lamb phase shift on the qubit array. We quantify the amount of the reservoir-induced entanglement and show how to experimentally evaluate it from the decay curve of the macroscopic polarization. We discuss how the beat signal can be discriminated from the other kinds of beat signals. We also show that our analysis can be used to estimate the reservoir characteristics

  15. Activating and Relaxing Music Entrains the Speed of Beat Synchronized Walking

    OpenAIRE

    Leman, Marc; Moelants, Dirk; Varewyck, Matthias; Styns, Frederik; van Noorden, Leon; Martens, Jean-Pierre

    2013-01-01

    Inspired by a theory of embodied music cognition, we investigate whether music can entrain the speed of beat synchronized walking. If human walking is in synchrony with the beat and all musical stimuli have the same duration and the same tempo, then differences in walking speed can only be the result of music-induced differences in stride length, thus reflecting the vigor or physical strength of the movement. Participants walked in an open field in synchrony with the beat of 52 different musi...

  16. 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.

  17. 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.

  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. 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.

  20. The neuronal norepinephrine transporter in experimental heart failure: evidence for a posttranscriptional downregulation.

    Science.gov (United States)

    Backs, J; Haunstetter, A; Gerber, S H; Metz, J; Borst, M M; Strasser, R H; Kübler, W; Haass, M

    2001-03-01

    An impairment of norepinephrine (NE) re-uptake by the neuronal NE transporter (NET) has been shown to contribute to the increased cardiac net-release of NE in congestive heart failure (CHF). The present study investigated which mechanisms are involved in the impairment of NET. Rats with supracoronary aortic banding characterized by myocardial hypertrophy, elevated left ventricular end diastolic pressures and severe pulmonary congestion were used as an experimental model for CHF. Compared to sham-operated controls, aortic-banded rats had enhanced plasma NE concentrations and decreased cardiac NE stores. In isolated perfused hearts of aortic-banded rats, functional impairment of NET was indicated by a 37% reduction in [(3)H]-NE-uptake. In addition, pharmacological blockade of NET with desipramine led to a markedly attenuated increase in the overflow of endogenous NE from hearts of aortic-banded rats. Determination of cardiac NET protein and of NET mRNA in the left stellate ganglion by [(3)H]-desipramine binding and competitive RT-PCR, respectively, revealed a 41% reduction of binding sites but no difference in gene expression. The density of sympathetic nerve fibers within the heart was unchanged, as shown by glyoxylic acid-induced histofluorescence. In conclusion, as impairment of intracardiac NE re-uptake by a reduction of NET binding sites is neither mediated by a decreased NET gene expression nor by a loss of noradrenergic nerve terminals, a posttranscriptional downregulation of NET per neuron is suggested in CHF. PMID:11181015