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Sample records for cardiac flow assessment

  1. Cardiac Assessment.

    Science.gov (United States)

    Fritz, Deborah; McKenzie, Patricia

    2015-10-01

    Heart disease remains the number one cause of mortality in both men and women in the United States and patients with heart failure are at high risk for hospitalization. Thirty-day readmission rates have become a benchmark for hospitals and home healthcare agency reimbursement. Physical exam and history taking are essential to evaluate patients with suspected or known heart disease, and to detect early symptoms of worsening heart failure. Home care clinicians have the opportunity to assess the patient in the home environment, identify significant changes in the patient's status, and form a plan of care for effective intervention to prevent the need for emergency department care or rehospitalization. In this second article of a four-part series, the subjective and objective assessment of the cardiovascular system exam is reviewed. PMID:26418104

  2. Cardiac Risk Assessment

    Science.gov (United States)

    ... to assess cardiac risk include: High-sensitivity C-reactive protein (hs-CRP) : Studies have shown that measuring ... LDL-C but does not respond to typical strategies to lower LDL-C such as diet, exercise, ...

  3. Assessment of coronary flow reserve by transesophageal echocardiography in cardiac transplant recipients.

    Science.gov (United States)

    Unger, P; Preumont, N; Vachiéry, J L; Bougard, M; Damhaut, P; Goldman, S; Berkenboom, G

    1998-06-01

    This study investigated the feasibility of dipyridamole Doppler transesophageal echocardiography to assess coronary flow reserve in 26 patients with orthotopic heart transplantation and compared it with positron emission tomography. We found an 85% success rate in obtaining Doppler flow signals in the proximal left anterior descending coronary artery. Our data also showed that the correlation between transesophageal echocardiography and dipyridamole N-13 ammonia positron emission tomography increases when respective resting rate-pressure products are taken into account. However, comparison between the two methods should be made with caution because coronary flow reserve derived from transesophageal echocardiography tends to be higher than that obtained with positron emission tomography. PMID:9657400

  4. Sudden Cardiac Arrest (SCA) Risk Assessment

    Science.gov (United States)

    ... Find a Specialist Share Twitter Facebook SCA Risk Assessment Sudden Cardiac Arrest (SCA) occurs abruptly and without ... of all ages and health conditions. Start Risk Assessment The Sudden Cardiac Arrest (SCA) Risk Assessment Tool ...

  5. Access flow reduction for cardiac failure.

    Science.gov (United States)

    Bourquelot, Pierre

    2016-03-01

    High-flow in hemodialysis arteriovenous angioaccesses is frequent. It may result in high-output cardiac failure, which should be prevented by fistula flow reduction. The most frequently reported flow reduction procedure is banding but immediate and long-term results are questionable. Alternative techniques are related here with personal results. Juxta-anastomosis "Proximal Radial Artery Ligation" (PRAL) is a very simple and effective reduction technique for side-to-end radio-cephalic fistulas (82 patients; reduction rate [RR]: 54% ± 19%). For brachial artery-based fistulas flow reduction two variants of Revision Using Distal Inflow (RUDI) procedures are used: 1) RUDI-1 using a polytetrafluoroethylene (PTFE) graft or a greater saphenous vein, which we first described in 1989 as "Distal Report of the Arterial Inflow" (35 patients; RR: 53% ± 18%), 2) RUDI-2 procedure, "Transposition of the Radial Artery", which we described in 2009 (47 patients; RR: 66% ± 14%). PMID:26951907

  6. Relationship between cardiac function and resting cerebral blood flow

    DEFF Research Database (Denmark)

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

    2014-01-01

    and cardiac output were measured in 31 healthy subjects 50-75 years old using magnetic resonance imaging techniques. Mean values of CBF, cardiac output and cardiac index were 43.6 ml per 100 g min(-1), 5.5 l min(-1) and 2.7 l min(-1) m(-2), respectively, in males, and 53.4 ml per 100 g min(-1), 4.3 l......Although both impaired cardiac function and reduced cerebral blood flow are associated with ageing, current knowledge of the influence of cardiac function on resting cerebral blood flow (CBF) is limited. The aim of this study was to investigate the potential effects of cardiac function on CBF. CBF...... min(-1) and 2.4 l min(-1) m(-2), respectively, in females. No effects of cardiac output or cardiac index on CBF or structural signs of brain ageing were observed. However, fractional brain flow defined as the ratio of total brain flow to cardiac output was inversely correlated with cardiac index (r(2...

  7. Assessment of cardiac sympathetic nerve integrity with positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Raffel, David M. E-mail: raffel@umich.edu; Wieland, Donald M

    2001-07-01

    The autonomic nervous system plays a critical role in the regulation of cardiac function. Abnormalities of cardiac innervation have been implicated in the pathophysiology of many heart diseases, including sudden cardiac death and congestive heart failure. In an effort to provide clinicians with the ability to regionally map cardiac innervation, several radiotracers for imaging cardiac sympathetic neurons have been developed. This paper reviews the development of neuronal imaging agents and discusses their emerging role in the noninvasive assessment of cardiac sympathetic innervation.

  8. Assessing and improving teamwork in cardiac surgery

    NARCIS (Netherlands)

    Schraagen, J.M.C.; Schouten, T.; Smit, M.; Haas, F.; Beek, D. van der; Ven, J. van de; Barach, P.

    2010-01-01

    Obiective Paediatric cardiac surgery {PCS) has a low enor tolerance, is dependent upon sophisticated organisational structures and demands high levels of cognitive and technical performance. The aim of the study was to assess the role of intraoperat¡ve non-routine events (NBEs) and team performance

  9. Pseudoaneurysm of the femoral artery after cardiac catheterisation: diagnosis and treatment by manual compression guided by Doppler colour flow imaging.

    OpenAIRE

    Currie, P; Turnbull, C M; Shaw, T R

    1994-01-01

    OBJECTIVE--To assess the value of Doppler colour flow imaging for diagnosing and guiding non-surgical treatment of pseudoaneurysm of the femoral artery complicating cardiac catheterisation. DESIGN--A prospective study. SETTING--Cardiac department in a teaching hospital. PATIENTS--9 patients (8 female, 1 male) who presented with pseudoaneurysm 1-15 days after cardiac catheterisation. INTERVENTIONS--The femoral arterial communication to the false aneurysm was localised by Doppler colour flow im...

  10. Design and assessment of cardiac SPECT systems

    Science.gov (United States)

    Lee, Chih-Jie

    Single-photon emission computed tomography (SPECT) is a modality widely used to detect myocardial ischemia and myocardial infarction. Objectively assessing and comparing different SPECT systems is important so that the best detectability of cardiac defects can be achieved. Whitaker, Clarkson, and Barrett's study on the scanning linear observer (SLO) shows that the SLO can be used to estimate the location and size of signals. One major advantage of the SLO is that it can be used with projection data rather than reconstruction data. Thus, this observer model assesses overall hardware performance independent by any reconstruction algorithm. In addition, we will show that the run time of image-quality studies is significantly reduced. Several systems derived from the GE CZT-based dedicated cardiac SPECT camera Discovery 530c design, which is officially named the Alcyone Technology: Discovery NM 530c, were assessed using the performance of the SLO for the task of detecting cardiac defects and estimating the properties of the defects. Clinically, hearts can be virtually segmented into three coronary artery territories: left anterior descending artery (LAD), left circumflex artery (LCX), and right coronary artery (RCA). One of the most important functions of a cardiac SPECT system is to produce images from which a radiologist can correctly predict in which territory the defect exists. A good estimation of the defect extent from the images is also very helpful for determining the seriousness of the myocardial ischemia. In this dissertation, both locations and extent of defects were estimated by the SLO, and system performance was assessed using localization receiver operating characteristic (LROC) / estimation receiver operating characteristic (EROC) curves. Area under LROC curve (AULC) / area under EROC curve (AUEC) and true positive fraction (TPF) at specific false positive fraction (FPF) can be treated as the gures of merit (FOMs). As the results will show, a

  11. Intraoperative Cardiac Ultrasound Examination Using Vector Flow Imaging

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Lindskov; Pedersen, Mads Møller; Møller-Sørensen, Hasse; Kjaergaard, Jesper; Nilsson, Jens Christian; Lund, Jens Teglgaard; Jensen, Jørgen Arendt; Bachmann, Michael Bachmann

    2013-01-01

    proposed. The vector flow method implemented on a Commercial scanner provided real-time, angle-independent estimates of cardiac blood flow. Epicardiac and epiaortic, intraoperative US examinations were performed on three patients with stenosed coronary arteries scheduled for bypass surgery. Repeating...

  12. Regional blood flow distribution in dog during induced hypotension and low cardiac output. Spontaneous breathing versus artificial ventilation.

    OpenAIRE

    Viires, N; Sillye, G; Aubier, M.; Rassidakis, A; Roussos, C

    1983-01-01

    Respiratory muscle blood flow and organ blood flow was studied in two groups of dogs with radioactively labeled microspheres to assess the influence of the working respiratory muscles on the regional distribution of blood flow when arterial pressure and cardiac output were lowered by pericardial tamponade. In one group (n = 6), the dogs were paralyzed and mechanically ventilated (Mv), while in the other (n = 6), they were left to breathe spontaneously (Sb). Cardiac output fell to 30% of contr...

  13. Relationship between cardiac output and effective renal plasma flow in patients with cardiac disease

    Energy Technology Data Exchange (ETDEWEB)

    McGriffin, D.; Tauxe, W.N.; Lewis, C.; Karp, R.; Mantle, J.

    1984-12-01

    The relationship between effective renal plasma flow (ERPF) and cardiac output was examined in 46 patients (22 with congestive heart failure and 24 following cardiac surgical procedures) by simultaneously measuring the global ERPF by the single-injection method and cardiac output by the thermodilution method. Of the patients in the heart-failure group, 21 also had pulmonary artery end diastolic pressure (PAEDP) recorded at the same time. ERPF and cardiac output were found to be related by the regression equations: cardiac output = 2.08 + 0.0065 ERPF (r, 080), with a SE of estimate of 0.81 l/min. ERPF and PAEDP were related by the regression equation: PAEDP = 42.02 - 0.0675 ERPF (r, 0.86), with a SE of estimate of 5.5 mm Hg. ERPF may be a useful noninvasive method of estimating cardiac output if it is known that no intrinsic kidney disease is present, and if the error of 0.81 l/min (1 SE of estimate) is within the range of clinical usefulness. The error is principally attributable to the determination of cardiac output by the thermodilution method.

  14. Cerebral blood flow in humans following resuscitation from cardiac arrest

    International Nuclear Information System (INIS)

    Cerebral blood flow was measured by xenon-133 washout in 13 patients 6-46 hours after being resuscitated from cardiac arrest. Patients regaining consciousness had relatively normal cerebral blood flow before regaining consciousness, but all patients who died without regaining consciousness had increased cerebral blood flow that appeared within 24 hours after resuscitation (except in one patient in whom the first measurement was delayed until 28 hours after resuscitation, by which time cerebral blood flow was increased). The cause of the delayed-onset increase in cerebral blood flow is not known, but the increase may have adverse effects on brain function and may indicate the onset of irreversible brain damage

  15. Cardiac cell proliferation assessed by EdU, a novel analysis of cardiac regeneration.

    Science.gov (United States)

    Zeng, Bin; Tong, Suiyang; Ren, Xiaofeng; Xia, Hao

    2016-08-01

    Emerging evidence suggests that mammalian hearts maintain the capacity for cardiac regeneration. Rapid and sensitive identification of cardiac cellular proliferation is prerequisite for understanding the underlying mechanisms and strategies of cardiac regeneration. The following immunologically related markers of cardiac cells were analyzed: cardiac transcription factors Nkx2.5 and Gata 4; specific marker of cardiomyocytes TnT; endothelial cell marker CD31; vascular smooth muscle marker smooth muscle myosin IgG; cardiac resident stem cells markers IsL1, Tbx18, and Wt1. Markers were co-localized in cardiac tissues of embryonic, neonatal, adult, and pathological samples by 5-ethynyl-2'-deoxyuridine (EdU) staining. EdU was also used to label isolated neonatal cardiomyocytes in vitro. EdU robustly labeled proliferating cells in vitro and in vivo, co-immunostaining with different cardiac cells markers. EdU can rapidly and sensitively label proliferating cardiac cells in developmental and pathological states. Cardiac cell proliferation assessed by EdU is a novel analytical tool for investigating the mechanism and strategies of cardiac regeneration in response to injury. PMID:25480318

  16. Assessment of Electrosurgery Burns in Cardiac Surgery

    Science.gov (United States)

    Jalali, Seyyed Mehdi; Moradi, Mohammad; Khalaj, Alireza; Pazouki, Alireza; Tamannaie, Zeinab; Ghanbari, Sajjad

    2015-01-01

    Background: Monopolar surgery is applied mostly in major operations, while bipolar is used in delicate ones. Attention must be paid in electrosurgery application to avoid electrical burns. Objectives: We aimed to assess factors associated with electrosurgery burns in cardiac surgery operating rooms. Patients and Methods: This was a case-control study in which two groups of 150 patients undergoing cardiac surgery in Imam Khomeini Hospital were recruited. Several factors like gender, age, operation duration, smoking, diseases, infection, atopia, , immunosuppressive drugs use, hepatic cirrhosis, and pulmonary diseases were compared between the two groups. Patients were observed for 24 hours for development of any burn related to the operation. Data was analyzed using SPSS v.11.5, by Chi square and T-test. Results: Patients in the two groups were similar except for two factors. DM and pulmonary diseases which showed significant differences (P = 0.005 and P = 0.002 respectively). Seventy-five patients from controls and 35 from the study group developed burns, which was significant (P ˂ 0.0001). Conclusions: None of the factors were significantly related to developing burns. The differences between the two groups highlights the importance of systems modifications to lessen the incidence of burns. PMID:26839854

  17. Cardiac Bypass Pump Flow Management via NIRS Monitoring

    OpenAIRE

    Macnab, Andrew J.; Gagnon, Roy E.; Gagnon, Faith A.; Blackstock, Derek; LeBlanc, Jacques G.

    2003-01-01

    During cardiac surgery, bypass pumps rely on pressure monitors to evaluate flow. We studied whether it would be possible to optimize pump flow by monitoring changes in cerebral cytochrome a,a3 using NIRS to maintain cyt redox status at its pre-bypass level. Method: 18 healthy 7–45 kg swine were placed on bypass for repeated cycles of cooling and re-warming from 36 to 15 to 36°C in 3°C steps. Between each cycle, the swine's bypass pump blood flow rate was adjusted to restore cytochrome redox s...

  18. Assessment of pulmonary function tests in cardiac patients

    OpenAIRE

    El-Sobkey, Salwa B.; Gomaa, Magdi

    2011-01-01

    This study was aimed to assess the pulmonary function tests (PFTs) in cardiac patients; with ischemic or rheumatic heart diseases as well as in patients who underwent coronary artery bypass graft (CABG) or valvular procedures. For the forty eligible participants, the pulmonary function was measured using the spirometry test before and after the cardiac surgery. Data collection sheet was used for the patient’s demographic and intra-operative information. Cardiac diseases and surgeries had rest...

  19. Environment Flow Assessment with Flow Regime Transition

    Science.gov (United States)

    Su, J.; Ho, C. C.; Chang, L. C.

    2015-12-01

    To avoid worsen river and estuarine ecosystems cause by overusing water resources, environmental flows conservation is applied to reduce the impact of river environment. Environmental flows refer to water provided within a river, wetland or coastal zone to sustain ecosystems and benefits to human wellbeing. Environment flow assessment is now widely accepted that a naturally variable flow regime, rather than just a minimum low flow. In this study, we propose four methods, experience method, Tenant method, hydraulic method and habitat method to assess the environmental flow of base flow, flush flow and overbank flow with different discharge, frequency and occurrence period. Dahan River has been chosen as a case to demonstrate the assessment mechanism. The alternatives impact analysis of environment and human water used provides a reference for stakeholders when holding an environmental flow consultative meeting.

  20. Functional cardiac MRI for assessment of aortic valve disease

    International Nuclear Information System (INIS)

    Aortic valve disease shows a rising incidence with the increasing mean age of Western populations. The detection of hemodynamic parameters, which transcends the mere assessment of valve morphology, has an important future potential concerning classification of the severity of disease. MRI allows a non-invasive and a spatially flexible view of the aortic valve and the adjacent anatomic region, left ventricular outflow tract (LVOT) and ascending aorta. Moreover, the technique allows the determination of functional hemodynamic parameters, such as flow velocities and effective orifice areas. The new approach of a serial systolic planimetry velocity-encoded MRI sequence (VENC-MRI) facilitates the sizing of blood-filled cardiac structures with the registration of changes in magnitude during systole. Additionally, the subvalvular VENC-MRI measurements improve the clinically important exact determination of the LVOT area with respect to its specific eccentric configuration and its systolic deformity. (orig.)

  1. Functional Relevance of Coronary Artery Disease by Cardiac Magnetic Resonance and Cardiac Computed Tomography: Myocardial Perfusion and Fractional Flow Reserve

    Directory of Open Access Journals (Sweden)

    Gianluca Pontone

    2015-01-01

    Full Text Available Coronary artery disease (CAD is one of the leading causes of morbidity and mortality and it is responsible for an increasing resource burden. The identification of patients at high risk for adverse events is crucial to select those who will receive the greatest benefit from revascularization. To this aim, several non-invasive functional imaging modalities are usually used as gatekeeper to invasive coronary angiography, but the diagnostic yield of elective invasive coronary angiography remains unfortunately low. Stress myocardial perfusion imaging by cardiac magnetic resonance (stress-CMR has emerged as an accurate technique for diagnosis and prognostic stratification of the patients with known or suspected CAD thanks to high spatial and temporal resolution, absence of ionizing radiation, and the multiparametric value including the assessment of cardiac anatomy, function, and viability. On the other side, cardiac computed tomography (CCT has emerged as unique technique providing coronary arteries anatomy and more recently, due to the introduction of stress-CCT and noninvasive fractional flow reserve (FFR-CT, functional relevance of CAD in a single shot scan. The current review evaluates the technical aspects and clinical experience of stress-CMR and CCT in the evaluation of functional relevance of CAD discussing the strength and weakness of each approach.

  2. Cardiac assessment of African hedgehogs (Atelerix albiventris).

    Science.gov (United States)

    Black, Peter A; Marshall, Cecilia; Seyfried, Alice W; Bartin, Anne M

    2011-03-01

    Cardiomyopathy is a common finding in captive African hedgehogs (Atelerix albiventris) at postmortem exam. To date, treatment attempts have been mostly empirical and unrewarding. The objective of this study was to determine reference cardiac values for captive African hedgehogs based on echocardiogram, electrocardiogram (ECG), and radiographs. Adult African hedgehogs with no clinical signs of cardiac disease (n = 13) were selected. Each animal was anesthetized with isoflurane via facemask and an echocardiogram, ECG, and radiographs were performed. Standard measurements were taken and the descriptive statistics performed. Values were comparable to limited data available in other hedgehog species and other similar-sized exotic species. Two animals were removed from consideration of reference values due to valvular defects that were considered significant. These data are the first establishing cardiac parameters in normal African hedgehogs using radiographic cardiac measurement, echocardiogram, and ECG. Evaluating animals with possible cardiomyopathy may allow for earlier diagnosis and more successful treatment. PMID:22946370

  3. Assessing Depression in Cardiac Patients: What Measures Should Be Considered?

    Directory of Open Access Journals (Sweden)

    M. Ceccarini

    2014-01-01

    Full Text Available It is highly recommended to promptly assess depression in heart disease patients as it represents a crucial risk factor which may result in premature deaths following acute cardiac events and a more severe psychopathology, even in cases of subsequent nonfatal cardiac events. Patients and professionals often underestimate or misjudge depressive symptomatology as cardiac symptoms; hence, quick, reliable, and early mood changes assessments are warranted. Failing to detect depressive signals may have detrimental effects on these patients’ wellbeing and full recovery. Choosing gold-standard depression investigations in cardiac patients that fit a hospitalised cardiac setting well is fundamental. This paper will examine eight well established tools following Italian and international guidelines on mood disorders diagnosis in cardiac patients: the Hospital Anxiety and Depression Scale (HADS, the Cognitive Behavioural Assessment Hospital Form (CBA-H, the Beck Depression Inventory (BDI, the two and nine-item Patient Health Questionnaire (PHQ-2, PHQ-9, the Depression Interview and Structured Hamilton (DISH, the Hamilton Rating Scale for Depression (HAM-D/HRSD, and the Composite International Diagnostic Interview (CIDI. Though their strengths and weaknesses may appear to be homogeneous, the BDI-II and the PHQ are more efficient towards an early depression assessment within cardiac hospitalised patients.

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

    International Nuclear Information System (INIS)

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

  5. Impairment of coronary flow reserve in orthotopic cardiac transplant recipients with minor coronary occlusive disease

    OpenAIRE

    Mullins, P. A.; Chauhan, A.; Sharples, L; Cary, N R; Large, S R; Wallwork, J; Schofield, P M

    1992-01-01

    Objective—Coronary occlusive disease is the major long-term complication after cardiac transplantation. The relation between minor angiographic abnormalities and myocardial perfusion has not been previously assessed in a large number of cardiac transplant patients.

  6. Advanced Analysis Techniques for Intra-cardiac Flow Evaluation from 4D Flow MRI

    OpenAIRE

    van der Geest, Rob J; Garg, Pankaj

    2016-01-01

    Purpose of the Review Time-resolved 3D velocity-encoded MR imaging with velocity encoding in three directions (4D Flow) has emerged as a novel MR acquisition technique providing detailed information on flow in the cardiovascular system. In contrast to other clinically available imaging techniques such as echo-Doppler, 4D Flow MRI provides the 3D Flow velocity field within a volumetric region of interest over the cardiac cycle. This work reviews the most recent advances in the development and ...

  7. The Clinical Assessment of Intraventricular Flows

    Science.gov (United States)

    Bermejo, Javier; Martínez-Legazpi, Pablo; del Álamo, Juan C.

    2015-01-01

    Recent advances in imaging techniques have allowed physicians to obtain robust measurements of intracardiac flows in the clinical setting. Consequently, the physiological implications of intraventricular fluid dynamics are beginning to be understood. Initial data show that these flows involve complex fluid-structure interactions and mixing phenomena that are modified by disease. Here we critically review the most important aspects of intraventricular fluid mechanics relevant for clinical applications. We discuss current image and numerical methods for assessing intraventricular flows, as well as implemented approaches to analyze their impact on cardiac function. The physiological and clinical insights provided by such techniques are discussed both in health and in disease. The final goal is to encourage research in the application of fluid dynamic foundations to patient-based clinical data. A huge potential is anticipated not only in terms of the basic science of large-scale biological systems, but also in practical terms of improving patient care.

  8. Determination of cardiac output, tissue blood flow, volume and lipid content in Sprague-Dawley rats

    International Nuclear Information System (INIS)

    One critical aspect of physiologically-based pharmacokinetic (PBPK) model development is the choice of values for organ blood flows, cardiac output and tissue volumes for input into models. These values vary depending upon the strain, size, age, and sex of animal for which a PBPK model is being developed. Tissue blood flows, cardiac output, tissue volume, and lipid content were determined in male S-D rats, (350-375 g, N=8). A radiolabel microsphere method utilizing Scandium (46Sc), Tin (113Sn),and Gadolinium (153Gd) was used to determine blood flow. Each rat received 3 radiolabeled injections. After the third injection, animals were sacrificed, and radioactivity in each tissue was determined in a 3-channel gamma counter. Tissues sampled include brain, heart, kidneys, liver, lungs, spleen, pancreas, adrenals, stomach, intestines, colon, testis, bone and skeletal muscle. Cardiac output was 142 ml/min. Blood flow values for eliminating organs were 0.49 (liver), 16.52 (kidney), and 1.77 (lung) ml/min/g tissue. Tissues which had significantly increased blood flow during the dark cycle included femur, abdonimal fat, triceps brachii and abdominal muscles, stomach, spleen and lung. Dissectable fat, organ volume, and organ lipid content were determined in a separate group of rats (N= 8). Volume and lipid content were determined for the same tissues as blood flow. Body fat was 7.35% of bw and extractable lipid content of eliminating organs was 42.3 (liver), 43.4 (kidney), and 35.9 (lung) mg/g tissue. Precise measurements should improve the accuracy of PBPK model predictions, and therfore help in reducing uncertainites in risk assessment of volatile organics and other pollutnats

  9. Sinus valsalva aneurysm on cardiac CT angiography: assessment and detection

    International Nuclear Information System (INIS)

    After the advent of ECG gated cardiac CT angiography (CCTA) there has been significant improvement in image quality of the ascending aorta. As a result the sinuses of valsalva are readily assessable. Sinuses of valsalva aneurysm can cause significant dysfunction of the aortic root and annulus and can be congenital or acquired. The aneurysm most commonly originates from the right coronary sinus. Complications related to sinuses of valsalva aneurysm can cause chest pain and can be life threatening. The cardiac imager should actively assess the sinuses of valsalva in every CCTA study.

  10. Cardiac causes of pulmonary arterial hypertension: assessment with multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    Hoey, Edward T.D.; Gopalan, Deepa; Agrawal, S.K.B. [Papworth Hospital, Cambridge (United Kingdom); Screaton, Nicholas J. [Papworth Hospital, Cambridge (United Kingdom); Papworth Hospital NHS Trust, Diagnostic Centre, Department of Radiology, Papworth Everard, Cambridgeshire (United Kingdom)

    2009-11-15

    The causes of pulmonary arterial hypertension (PAH) are diverse and include multiple congenital and acquired cardiac diseases as well as diseases primarily affecting the pulmonary vasculature, lung, pleura and chest wall. The traditional role of CT in evaluating PAH includes assessment of pulmonary vasculature and lung parenchyma with limited assessment of the heart. Advances in multidetector CT technology with improved spatial and temporal resolution now permit accurate delineation of cardiac morphology. CT pulmonary angiography (CTPA) is widely utilised in the workup of patients with suspected pulmonary vascular disease and can identify both pulmonary and cardiac causes. As the initial presentation for CTPA is often precipitated by nonspecific, unexplained symptoms and therefore undertaken by a general radiologist, it is important that a systematic approach to the interpretation of these studies, including cardiac evaluation, is routinely adopted. This paper reviews the CT evaluation in pulmonary hypertension with a particular focus on the cardiac causes, their subclassification into congenital systemic to pulmonary shunts and secondary to left heart disease, and their imaging features. It emphasises the use of a systematic approach to interpretation of CTPA examinations both in patients with known PAH and those with previously unsuspected disease. (orig.)

  11. Left and right ventricle assessment with Cardiac CT: validation study vs. Cardiac MR

    Energy Technology Data Exchange (ETDEWEB)

    Maffei, Erica; Seitun, Sara [Giovanni XXIII Hospital, Cardiovascular Radiology Unit, Monastier di Treviso (Italy); Messalli, Giancarlo; Catalano, Onofrio [SDN Foundation - IRCCS, Naples (Italy); Martini, Chiara; Cademartiri, Filippo [Giovanni XXIII Hospital, Cardiovascular Radiology Unit, Monastier di Treviso (Italy); Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Nieman, Koen; Rossi, Alexia; Mollet, Nico R. [Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Guaricci, Andrea I. [Azienda Ospedaliero-Universitaria di Foggia, Department of Cardiology, Foggia (Italy); Tedeschi, Carlo [Ospedale San Gennaro, Department of Cardiology, Naples (Italy)

    2012-05-15

    To compare Magnetic Resonance (MR) and Computed Tomography (CT) for the assessment of left (LV) and right (RV) ventricular functional parameters. Seventy nine patients underwent both Cardiac CT and Cardiac MR. Images were acquired using short axis (SAX) reconstructions for CT and 2D cine b-SSFP (balanced-steady state free precession) SAX sequence for MR, and evaluated using dedicated software. CT and MR images showed good agreement: LV EF (Ejection Fraction) (52 {+-} 14% for CT vs. 52 {+-} 14% for MR; r = 0.73; p > 0.05); RV EF (47 {+-} 12% for CT vs. 47 {+-} 12% for MR; r = 0.74; p > 0.05); LV EDV (End Diastolic Volume) (74 {+-} 21 ml/m{sup 2} for CT vs. 76 {+-} 25 ml/m{sup 2} for MR; r = 0.59; p > 0.05); RV EDV (84 {+-} 25 ml/m{sup 2} for CT vs. 80 {+-} 23 ml/m{sup 2} for MR; r = 0.58; p > 0.05); LV ESV (End Systolic Volume)(37 {+-} 19 ml/m{sup 2} for CT vs. 38 {+-} 23 ml/m{sup 2} for MR; r = 0.76; p > 0.05); RV ESV (46 {+-} 21 ml/m{sup 2} for CT vs. 43 {+-} 18 ml/m{sup 2} for MR; r = 0.70; p > 0.05). Intra- and inter-observer variability were good, and the performance of CT was maintained for different EF subgroups. Cardiac CT provides accurate and reproducible LV and RV volume parameters compared with MR, and can be considered as a reliable alternative for patients who are not suitable to undergo MR. circle Cardiac-CT is able to provide Left and Right Ventricular function. circle Cardiac-CT is accurate as MR for LV and RV volume assessment. (orig.)

  12. Epidural catheterization in cardiac surgery: The 2012 risk assessment

    Directory of Open Access Journals (Sweden)

    Thomas M Hemmerling

    2013-01-01

    Full Text Available Aims and Objectives: The risk assessment of epidural hematoma due to catheter placement in patients undergoing cardiac surgery is essential since its benefits have to be weighed against risks, such as the risk of paraplegia. We determined the risk of the catheter-related epidural hematoma in cardiac surgery based on the cases reported in the literature up to September 2012. Materials and Methods: We included all reported cases of epidural catheter placement for cardiac surgery in web and in literature from 1966 to September 2012. Risks of other medical and non-medical activities were retrieved from recent reviews or national statistical reports. Results: Based on our analysis the risk of catheter-related epidural hematoma is 1 in 5493 with a 95% confidence interval (CI of 1/970-1/31114. The risk of catheter-related epidural hematoma in cardiac surgery is similar to the risk in the general surgery population at 1 in 6,628 (95% CI 1/1,170-1/37,552. Conclusions: The present risk calculation does not justify not offering epidural analgesia as part of a multimodal analgesia protocol in cardiac surgery.

  13. Assessing Cardiac Dynamics based on X-Ray Coronary Angiograms

    Directory of Open Access Journals (Sweden)

    Zheng Sun

    2013-02-01

    Full Text Available The problem of quantitatively assessing cardiac motion including global and local dynamic performances during cardiac cycles is addressed. In vivo X-ray coronary angiographic image sequences covering several cardiac cycles are used as source image data. The three-dimensional (3-D surface of the heart based on extended superquadrics (ESQ surface model in each phase is constructed from 3-D coronary vessel skeletons, which are reconstructed from a pair of nearly orthogonal angiographic sequences. Complex dynamic performances of the heart are decomposed into global and local components according to a priori anatomical and dynamic knowledge that have been confirmed by medical observations and non-rigid motion theory. Parameters of all components are quantitatively estimated through motion decomposition and compensation. Consequently, cardiac dynamics during cardiac cycles are comprehensively depicted with quantitative parameters. Validation of the proposed method with clinically acquired in vivo image data has been carried out, the results of which have verified the feasibility and accuracy of the proposed method.

  14. Assessment of cardiac output changes using a modified FloTrac/Vigileo™ algorithm in cardiac surgery patients

    OpenAIRE

    Senn, Alban; Button, Danny; Zollinger, Andreas; Hofer, Christoph K

    2009-01-01

    Introduction The FloTrac/Vigileo™ (Edwards Lifesciences, Irvine, CA, USA) allows pulse pressure-derived cardiac output measurement without external calibration. Software modifications were performed in order to eliminate initially observed deficits. The aim of this study was to assess changes in cardiac output determined by the FloTrac/Vigileo™ system (FCO) with an initially released (FCOA) and a modified (FCOB) software version, as well as changes in cardiac output from the PiCCOplus™ system...

  15. Automatic assessment of cardiac perfusion MRI

    DEFF Research Database (Denmark)

    Ólafsdóttir, Hildur; Stegmann, Mikkel Bille; Larsson, Henrik B.W.

    2004-01-01

    In this paper, a method based on Active Appearance Models (AAM) is applied for automatic registration of myocardial perfusion MRI. A semi-quantitative perfusion assessment of the registered image sequences is presented. This includes the formation of perfusion maps for three parameters; maximum up...

  16. Automatic assessment of cardiac perfusion MRI

    OpenAIRE

    Ólafsdóttir, Hildur; Stegmann, Mikkel Bille; Larsson, Henrik B. W.

    2004-01-01

    In this paper, a method based on Active Appearance Models (AAM) is applied for automatic registration of myocardial perfusion MRI. A semi-quantitative perfusion assessment of the registered image sequences is presented. This includes the formation of perfusion maps for three parameters; maximum up-slope, peak and time-to-peak.

  17. Epicardial fat volume assessment in cardiac CT

    OpenAIRE

    Coppini, Giuseppe; Favilla, Riccardo; Moroni, Davide; Salvetti, Ovidio; D'Errico, Luigina; Salituri, F; Ciardetti, Marco; Schlueter, Mathis; Faggioni, Luca; Coceani, Michele; Mazzarisi, Alessandro; M. Bianchi; Bartolozzi, C; Marraccini, Paolo

    2012-01-01

    Epicardial fat, as other visceral fat localizations, is correlated with car- diovascular disease, cardiovascular risk factors and metabolic syndrome. However, many concerns remain about the method for measuring epi- cardial fat, its regional distribution on the myocardium, as well as the accuracy and reproducibility of such measurements. At present, dedi- cated software procedures to assess epicardial fat are lacking. On the other hand, manual fat segmentation requires a huge and tedious oper...

  18. Imminent Cardiac Risk Assessment via Optical Intravascular Biochemical Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wetzel, D.; Wetzel, L; Wetzel, M; Lodder, R

    2009-01-01

    Heart disease is by far the biggest killer in the United States, and type II diabetes, which affects 8% of the U.S. population, is on the rise. In many cases, the acute coronary syndrome and/or sudden cardiac death occurs without warning. Atherosclerosis has known behavioral, genetic and dietary risk factors. However, our laboratory studies with animal models and human post-mortem tissue using FT-IR microspectroscopy reveal the chemical microstructure within arteries and in the arterial walls themselves. These include spectra obtained from the aortas of ApoE-/- knockout mice on sucrose and normal diets showing lipid deposition in the former case. Also pre-aneurysm chemical images of knockout mouse aorta walls, and spectra of plaque excised from a living human patient are shown for comparison. In keeping with the theme of the SPEC 2008 conference Spectroscopic Diagnosis of Disease this paper describes the background and potential value of a new catheter-based system to provide in vivo biochemical analysis of plaque in human coronary arteries. We report the following: (1) results of FT-IR microspectroscopy on animal models of vascular disease to illustrate the localized chemical distinctions between pathological and normal tissue, (2) current diagnostic techniques used for risk assessment of patients with potential unstable coronary syndromes, and (3) the advantages and limitations of each of these techniques illustrated with patent care histories, related in the first person, by the physician coauthors. Note that the physician comments clarify the contribution of each diagnostic technique to imminent cardiac risk assessment in a clinical setting, leading to the appreciation of what localized intravascular chemical analysis can contribute as an add-on diagnostic tool. The quality of medical imaging has improved dramatically since the turn of the century. Among clinical non-invasive diagnostic tools, laboratory tests of body fluids, EKG, and physical examination are

  19. REGIONAL CARDIAC BLOOD FLOW WITH AIR PARTICLE EXPOSURE

    Science.gov (United States)

    This proposal offers the unique application of novel techniques to improve understanding of the mechanisms whereby ambient particulate exerts deleterious influences on the heart and circulation. Enhanced ischemia has broad implications for cardiac morbidity and mor...

  20. QTc interval in the assessment of cardiac risk

    DEFF Research Database (Denmark)

    Elming, Hanne; Brendorp, Bente; Køber, Lars; Sahebzadah, Najia; Torp-Petersen, Christian

    2002-01-01

    with increased risk of arrhythmias. The paper gives a review of the possibilities to assess the risk of ventricular arrhythmia and/or cardiac death from QTc. Prolonged QTc may hold independent prognostic importance for mortality in common diseases as ischemic heart disease and diabetes mellitus where...... prognostic importance in hypertrophic cardiomyopathy or in the arrhythmogenic right ventricular disease. The degree of QTc prolonging during treatment with QTc prolonging drugs is prognostic for the risk of ventricular arrhythmia in form of torsade de pointes and QTc prolonging drugs should probably not be...

  1. Which concentration to choose in dual flow cardiac CT?

    International Nuclear Information System (INIS)

    Purpose: An extensive number of protocols have been suggested to allow for functional diagnostics; however, no data is available about the minimal amount of contrast medium to achieve reliable imaging properties. None of the plethora of existing studies report a rational why the specific concentration was chosen. Materials and methods: A total of 40 patients were included in this prospective, controlled study. They were divided up into four equal groups getting a different concentration (10%, 20%, 30% or 40%) of a second contrast medium bolus. Corresponding septal and right ventricular ROIs were compared. A visual score was established. Coronary attenuation was measured in the right and left coronary artery. Streak artifacts in the right atrium/ventricle were assessed. Results: In the 10% contrast medium (CM) group only in 5/10 (50%) patients full septal delineation was reached. In all other groups full septal visualization was obtained. No group showed a relevant difference of mean density measured in HU units of the left ventricle or the coronary arteries. All study groups except of group 1 (10% CM) showed streak artifacts in the right atrium. Conclusion: The dual flow protocol with a minimum concentration of 20% improves septal visualization as basis for left ventricular functional assessment, however, does not allow for reliable right ventricular or atrial visualization. There is no significant difference between the different concentration protocols in terms of coronary attenuation.

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

    International Nuclear Information System (INIS)

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

  3. Scintigraphic assessment of cardiac sympathetic innervation with I-123-metaiodobenzylguanidine in cardiomyopathy. Special reference to cardiac arrhythmia

    International Nuclear Information System (INIS)

    Cardiac sympathetic imagings with I-123-metaiodobenzylguanidine (MIBG) were carried out in 5 cases with dilated cardiomyopathy (DCM), 26 cases with hypertrophic cardiomyopathy (HCM), and 4 cases without cardiac disease as a control to assess cardiac sympathetic innervation qualitatively and quantitatively, and to clarify the relation of MIBG accumulation to arrhythmia. MIBG scintigraphy was performed at 15 min. (early image) and 4 hr. (delayed image) after intravenous injection of MIBG 111 MBq. The MIBG uptake ratio of mediastinum (H/M) and the cardiac washout rate (WR) from early to delayed images were calculated. On both early and delayed SPECTs, MIBG uptake was assessed by defect scores (DSs). Regarding the cases with HCM, the MIBG uptake ratio, WR, and DS were also compared in cases with and without arrhythmia. In DCM, the MIBG uptake on delayed SPECT was markedly low, the H/M ratio was significantly lower, and the DS was significantly higher than in the control (all p<0.05). As for the WR, there was no significant difference between HCM, DCM and the control. In HCM, significantly reduced MIBG uptake was observed in cases with ventricular techycardia (VT) and in cases with atrial fibrillation (Af), as compared with cases without arrhythmia (all p<0.05). There results suggest that MIBG scintigraphy might be a useful tool in the assessment of cardiac sympathetic abnormalities in cardiomyopathy, especially in cases with arrhythmia. (author)

  4. Scintigraphic assessment of cardiac sympathetic innervation with I-123-metaiodobenzylguanidine in cardiomyopathy. Special reference to cardiac arrhythmia

    Energy Technology Data Exchange (ETDEWEB)

    Asano, Takahisa; Otsuka, Nobuaki; Sone, Teruki; Mimura, Hiroaki; Yanagimoto, Shinichi; Tomomitsu, Tatsushi; Fukunaga, Masao [Kawasaki Medical School, Kurashiki, Okayama (Japan); Morita, Koichi

    1999-07-01

    Cardiac sympathetic imagings with I-123-metaiodobenzylguanidine (MIBG) were carried out in 5 cases with dilated cardiomyopathy (DCM), 26 cases with hypertrophic cardiomyopathy (HCM), and 4 cases without cardiac disease as a control to assess cardiac sympathetic innervation qualitatively and quantitatively, and to clarify the relation of MIBG accumulation to arrhythmia. MIBG scintigraphy was performed at 15 min. (early image) and 4 hr. (delayed image) after intravenous injection of MIBG 111 MBq. The MIBG uptake ratio of mediastinum (H/M) and the cardiac washout rate (WR) from early to delayed images were calculated. On both early and delayed SPECTs, MIBG uptake was assessed by defect scores (DSs). Regarding the cases with HCM, the MIBG uptake ratio, WR, and DS were also compared in cases with and without arrhythmia. In DCM, the MIBG uptake on delayed SPECT was markedly low, the H/M ratio was significantly lower, and the DS was significantly higher than in the control (all p<0.05). As for the WR, there was no significant difference between HCM, DCM and the control. In HCM, significantly reduced MIBG uptake was observed in cases with ventricular techycardia (VT) and in cases with atrial fibrillation (Af), as compared with cases without arrhythmia (all p<0.05). There results suggest that MIBG scintigraphy might be a useful tool in the assessment of cardiac sympathetic abnormalities in cardiomyopathy, especially in cases with arrhythmia. (author)

  5. The Effects That Cardiac Motion has on Coronary Hemodynamics and Catheter Trackability Forces for the Treatment of Coronary Artery Disease: An In Vitro Assessment.

    Science.gov (United States)

    Morris, Liam; Fahy, Paul; Stefanov, Florian; Finn, Ronan

    2015-12-01

    The coronary arterial tree experiences large displacements due to the contraction and expansion of the cardiac muscle and may influence coronary haemodynamics and stent placement. The accurate measurement of catheter trackability forces within physiological relevant test systems is required for optimum catheter design. The effects of cardiac motion on coronary flowrates, pressure drops, and stent delivery has not been previously experimentally assessed. A cardiac simulator was designed and manufactured which replicates physiological coronary flowrates and cardiac motion within a patient-specific geometry. A motorized delivery system delivered a commercially available coronary stent system and monitored the trackability forces along three phantom patient-specific thin walled compliant coronary vessels supported by a dynamic cardiac phantom model. Pressure drop variation is more sensitive to cardiac motion than outlet flowrates. Maximum pressure drops varied from 7 to 49 mmHg for a stenosis % area reduction of 56 to 90%. There was a strong positive linear correlation of cumulative trackability force with the cumulative curvature. The maximum trackability forces and curvature ranged from 0.24 to 0.87 N and 0.06 to 0.22 mm(-1) respectively for all three vessels. There were maximum and average percentage differences in trackability forces of (23-49%) and (1.9-5.2%) respectively when comparing a static pressure case with the inclusion of pulsatile flow and cardiac motion. Cardiac motion with pulsatile flow significantly altered (p value local percentage variations and pressure drop measurements. PMID:26577477

  6. Wavelet transform analysis to assess oscillations in pial artery pulsation at the human cardiac frequency.

    Science.gov (United States)

    Winklewski, P J; Gruszecki, M; Wolf, J; Swierblewska, E; Kunicka, K; Wszedybyl-Winklewska, M; Guminski, W; Zabulewicz, J; Frydrychowski, A F; Bieniaszewski, L; Narkiewicz, K

    2015-05-01

    Pial artery adjustments to changes in blood pressure (BP) may last only seconds in humans. Using a novel method called near-infrared transillumination backscattering sounding (NIR-T/BSS) that allows for the non-invasive measurement of pial artery pulsation (cc-TQ) in humans, we aimed to assess the relationship between spontaneous oscillations in BP and cc-TQ at frequencies between 0.5 Hz and 5 Hz. We hypothesized that analysis of very short data segments would enable the estimation of changes in the cardiac contribution to the BP vs. cc-TQ relationship during very rapid pial artery adjustments to external stimuli. BP and pial artery oscillations during baseline (70s and 10s signals) and the response to maximal breath-hold apnea were studied in eighteen healthy subjects. The cc-TQ was measured using NIR-T/BSS; cerebral blood flow velocity, the pulsatility index and the resistive index were measured using Doppler ultrasound of the left internal carotid artery; heart rate and beat-to-beat systolic and diastolic blood pressure were recorded using a Finometer; end-tidal CO2 was measured using a medical gas analyzer. Wavelet transform analysis was used to assess the relationship between BP and cc-TQ oscillations. The recordings lasting 10s and representing 10 cycles with a frequency of ~1 Hz provided sufficient accuracy with respect to wavelet coherence and wavelet phase coherence values and yielded similar results to those obtained from approximately 70cycles (70s). A slight but significant decrease in wavelet coherence between augmented BP and cc-TQ oscillations was observed by the end of apnea. Wavelet transform analysis can be used to assess the relationship between BP and cc-TQ oscillations at cardiac frequency using signals intervals as short as 10s. Apnea slightly decreases the contribution of cardiac activity to BP and cc-TQ oscillations. PMID:25804326

  7. Assessment of Cardiac Motion Effects on the Fiber Architecture of the Human Heart In Vivo

    OpenAIRE

    Wei, Hongjiang; Viallon, Magalie; Delattre, Benedicte M. A.; Wang, Lihui; Pai, Vinay M; Wen, Han; Xue, Hui; Guetter, Christoph; Croisille, Pierre; Zhu, Yuemin

    2013-01-01

    The use of diffusion tensor imaging (DTI) for studying the human heart in vivo is very challenging due to cardiac motion. This paper assesses the effects of cardiac motion on the human myocardial fiber architecture. To this end, a model for analyzing the effects of cardiac motion on signal intensity is presented. A Monte-Carlo simulation based on polarized light imaging data is then performed to calculate the diffusion signals obtained by the displacement of water molecules, which generate di...

  8. Clinical Assessment of Intraventricular Blood Transport in Patients Undergoing Cardiac Resynchronization Therapy

    Science.gov (United States)

    Rossini, Lorenzo; Martinez-Legazpi, P.; Benito, Y.; Perez Del Villar, C.; Gonzalez-Mansilla, A.; Barrio, A.; Yotti, R.; Kahn, A. M.; Shadden, S. C.; Fernandez-Aviles, F.; Bermejo, J.; Del Alamo, J. C.

    2015-11-01

    In the healthy heart, left ventricular (LV) filling generates flow patterns which have been proposed to optimize blood transport by coupling diastole and systole phases. We present a novel image-based method to assess how flow patterns influence LV blood transport in patients undergoing cardiac resynchronization therapy (CRT). Solving the advection equation with time-varying inflow boundary conditions allows to track the transport of blood entering the LV in the different filling waves, as well as the transport barriers which couple filling and ejection. The velocity fields were obtained using echocardiographic color Doppler velocimetry, which provides two-dimensional time-resolved flow maps in the apical long axis three-chamber view of the LV. We analyze flow transport in a group of patients with CRT devices as well as in healthy volunteers. In the patients under CRT, the device programming was varied to analyze flow transport under different values of the atrioventricular (AV) conduction delay and to model tachycardia. This analysis illustrates how CRT influences the transit of blood inside the LV, contributes to conserving kinetic energy and favors the generation of hemodynamic forces that accelerate blood in the direction of the LV outflow tract.

  9. A sensitive flow-through microcalorimeter for measuring the heat production of cardiac trabeculae.

    Science.gov (United States)

    Taberner, A; Kirton, R; F Nielsen, P; Loiselle, D; Hunter, I

    2004-01-01

    Measurement of the energy consumption of isolated cardiac muscle requires a flow-through microcalorimeter with sensitivity in the microW range. In this paper we describe and characterize a sensitive flow-through microcalorimeter, designed and constructed for measuring the heat output of cardiac trabeculae. The device exploits a non-contact, temperature-sensing technique utilizing infra-red-sensitive, thin-film thermopile sensors. The microcalorimeter achieves a sensitivity of 1.8-1.9 V/W at a flow rate of 1 microl/s, with a time constant of approximately 3.5 s. The typical power signal-to-noise ratio is better than 200. Predictions of a finite element model of the calorimeter's characteristics compare favourably with measured data. PMID:17272117

  10. Probing cardiac repolarization reserve in drug safety assessment

    NARCIS (Netherlands)

    Nalos, L.

    2011-01-01

    Excessive prolongation of cardiac repolarization, manifested as QT prolongation on ECG, is common unwanted side effect of many drugs and drug candidates. Prolongation of QT interval may lead to life threatening cardiac arrhythmia – Torsade de Point (TdP). Number of drugs was withdrawn from the marke

  11. Is standardized cardiac assessment of asymptomatic high-risk renal transplant candidates beneficial?

    NARCIS (Netherlands)

    Aalten, J.; Peeters, S.A.; Vlugt, M.J. van der; Hoitsma, A.J.

    2011-01-01

    BACKGROUND: Perioperative cardiovascular events in renal transplantation are common and non-invasive cardiac stress tests are recommended in high-risk renal transplant candidates. In 2004, we introduced a standardized preoperative cardiac risk assessment programme with the aim of reducing perioperat

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

    Science.gov (United States)

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

    2009-04-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-04-07

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

  14. Developing a visualized patient-centered, flow-based and objective-oriented care path of cardiac catheterization examination.

    Science.gov (United States)

    Kuo, Ming Chuan; Chang, Polun

    2009-01-01

    It has been known that visualization is a user-preferred and more meaningful interface of information systems. To reduce the anxiety and uncertainty of patients, we transformed the sophisticated process of cardiac catheterization into visualized information. The Microsoft Visio 2003 and Excel 2003 with the VBA automation tool were used to design a process flow of Cardiac Catheterization. The results show the technical feasibility and potentials helpful for patient to realize the nursing process of cardiac catheterization. PMID:19593031

  15. Use of the cardiopulmonary flow index to evaluate cardiac function in thoroughbred horses

    International Nuclear Information System (INIS)

    The ratio of the cardiopulmonary blood volume to stroke volume is called the cardiopulmonary flow index (CPFI). The CPFI can be determined indirectly from the simultaneous recording of a radiocardiogram and an electrocardiogram. The CPFI and cardiac output were measured simultaneously in horses that were diagnosed as having cardiac disease. The results obtained from these subjects were compared with those from control animals and significant differences were found between the mean CPFI of the control horses and those with macroscopically visible myocardial fibrosis on post mortem examination. No significant differences were found between the means of the cardiac output measured in either of the groups of horses. The effect of pharmacological acceleration of the heart rate on the CPFI was also studied. Significant differences were found between the mean CPFI and the slopes of the regression lines of CPFI on heart rate of the control and principal groups of horses. These differences were greatest at heart rates near to the resting heart rates of the individuals. The CPFI was found to be a more sensitive measure of cardiac function than cardiac output, in the horses. 16 refs., 2 figs., 2 tabs

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

    Directory of Open Access Journals (Sweden)

    Leng Xiaoyan

    2009-11-01

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

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

    Science.gov (United States)

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

    2011-01-01

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

  18. Cancer treatment-related cardiac toxicity: prevention, assessment and management.

    Science.gov (United States)

    Fanous, Ibrahim; Dillon, Patrick

    2016-08-01

    Cancer therapies, especially anthracyclines and monoclonal antibodies, have been linked with increased rates of cardiotoxicity. The development of some cardiac side effects happens over several months, and changes in ejection fraction can be detected long before permanent damage or disability occurs. Advanced heart failure could be averted with better and earlier detection. Methodologies for early detection of cardiac changes include stress echocardiograms, cardiac velocity measurements, radionuclide imaging, cardiac MRI and several potential biomarkers. Many agents have been described for prophylaxis of cardiac events precipitated by cancer therapy. Prophylactic use of beta-blockers and ACE inhibitors may be considered for use with trastuzumab in breast cancer as tolerated. Recovery of cardiac function is possible early after the injury from a cancer therapy. Late complications for coronary artery disease, hypertension and arrhythmia are underappreciated. Treatments for severe cancer therapy-related cardiac complications follow the existing paradigms for congestive heart failure and coronary artery disease, although outcomes for cancer patients differ from outcomes for non-cancer patients. PMID:27372782

  19. QUALITY OF LIFE ASSESSMENT IN CARDIAC TRANSPLANT RECIPIENTS

    Directory of Open Access Journals (Sweden)

    A. O. Shevchenko

    2014-01-01

    Full Text Available Background. Quality of life (QoL is an important criterion for the treatment effi cacy that provides an important data regarding patient’s personal estimation of social adaptation and ability to perform daily duties.Methods. The study was aimed to evaluate QoL in cardiac transplant recipients. We have enrolled 42 stage D heart failure patients aged 29–61 (mean 39,23 ± 12,31 y/o, 38 males and 4 females, survived cardiac transplant surgery between Jan 2008 and Jan 2013. QoL was evaluated using the SF-36 survey prior to the heart surgery and during the follow-up period up to the 5 years.Results. Pre-operative assessment revealed low QoL indices of physical activity as well as general health status. Follow-up showed dramatic improvement in all QoL measures during 1 year after the surgery which was consistent through the whole observation period. There was an increase in physical functioning index by 2,8 times (p < 0,01, physical status dependent role functioning by 14 times (р < 0,0001, emotional status dependent role functioning by 3 times (р = 0,02, social functioning by 4,8 times (p = 0,002, pain threshold by 3 times (p = 0,02, psychic health by 3,6 times (p = 0,001, life activity by 2,6 times(p = 0,003, and total health by 1,6 times (p = 0,03. Physical activity was restored in 90% of patients during the fi rst year.Conclusion. The study shows signifi cant improvement in all QoL variables after heart transplantation in stage D heart failure patients. Main indices of physical, psychical, and social activities rise at the fi rst year and remain high during the 5-year period. These data support heart transplantation as a radical and effective method of terminal heart failure treatment.

  20. Design of a pulsatile flow facility to evaluate thrombogenic potential of implantable cardiac devices.

    Science.gov (United States)

    Arjunon, Sivakkumar; Ardana, Pablo Hidalgo; Saikrishnan, Neelakantan; Madhani, Shalv; Foster, Brent; Glezer, Ari; Yoganathan, Ajit P

    2015-04-01

    Due to expensive nature of clinical trials, implantable cardiac devices should first be extensively characterized in vitro. Prosthetic heart valves (PHVs), an important class of these devices, have been shown to be associated with thromboembolic complications. Although various in vitro systems have been designed to quantify blood-cell damage and platelet activation caused by nonphysiological hemodynamic shear stresses in these PHVs, very few systems attempt to characterize both blood damage and fluid dynamics aspects of PHVs in the same test system. Various numerical modeling methodologies are also evolving to simulate the structural mechanics, fluid mechanics, and blood damage aspects of these devices. This article presents a completely hemocompatible small-volume test-platform that can be used for thrombogenicity studies and experimental fluid mechanics characterization. Using a programmable piston pump to drive freshly drawn human blood inside a cylindrical column, the presented system can simulate various physiological and pathophysiological conditions in testing PHVs. The system includes a modular device-mounting chamber, and in this presented case, a 23 mm St. Jude Medical (SJM) Regents® mechanical heart valve (MHV) in aortic position was used as the test device. The system was validated for its capability to quantify blood damage by measuring blood damage induced by the tester itself (using freshly drawn whole human blood). Blood damage levels were ascertained through clinically relevant assays on human blood while fluid dynamics were characterized using time-resolved particle image velocimetry (PIV) using a blood-mimicking fluid. Blood damage induced by the tester itself, assessed through Thrombin-anti-Thrombin (TAT), Prothrombin factor 1.2 (PF1.2), and hemolysis (Drabkins assay), was within clinically accepted levels. The hydrodynamic performance of the tester showed consistent, repeatable physiological pressure and flow conditions. In addition, the

  1. Evaluation of coronary blood flow velocity during cardiac arrest with circulation maintained through mechanical chest compressions in a porcine model

    OpenAIRE

    Wagner Henrik; Madsen Hardig Bjarne; Steen Stig; Sjoberg Trygve; Harnek Jan; Olivecrona Goran K

    2011-01-01

    Abstract Background Mechanical chest compressions (CCs) have been shown capable of maintaining circulation in humans suffering cardiac arrest for extensive periods of time. Reports have documented a visually normalized coronary blood flow during angiography in such cases (TIMI III flow), but it has never been actually measured. Only indirect measurements of the coronary circulation during cardiac arrest with on-going mechanical CCs have been performed previously through measurement of the cor...

  2. Cardiac tumours in children

    Directory of Open Access Journals (Sweden)

    Parsons Jonathan M

    2007-03-01

    Full Text Available Abstract Cardiac tumours are benign or malignant neoplasms arising primarily in the inner lining, muscle layer, or the surrounding pericardium of the heart. They can be primary or metastatic. Primary cardiac tumours are rare in paediatric practice with a prevalence of 0.0017 to 0.28 in autopsy series. In contrast, the incidence of cardiac tumours during foetal life has been reported to be approximately 0.14%. The vast majority of primary cardiac tumours in children are benign, whilst approximately 10% are malignant. Secondary malignant tumours are 10–20 times more prevalent than primary malignant tumours. Rhabdomyoma is the most common cardiac tumour during foetal life and childhood. It accounts for more than 60% of all primary cardiac tumours. The frequency and type of cardiac tumours in adults differ from those in children with 75% being benign and 25% being malignant. Myxomas are the most common primary tumours in adults constituting 40% of benign tumours. Sarcomas make up 75% of malignant cardiac masses. Echocardiography, Computing Tomography (CT and Magnetic Resonance Imaging (MRI of the heart are the main non-invasive diagnostic tools. Cardiac catheterisation is seldom necessary. Tumour biopsy with histological assessment remains the gold standard for confirmation of the diagnosis. Surgical resection of primary cardiac tumours should be considered to relieve symptoms and mechanical obstruction to blood flow. The outcome of surgical resection in symptomatic, non-myxomatous benign cardiac tumours is favourable. Patients with primary cardiac malignancies may benefit from palliative surgery but this approach should not be recommended for patients with metastatic cardiac tumours. Surgery, chemotherapy and radiotherapy may prolong survival. The prognosis for malignant primary cardiac tumours is generally extremely poor.

  3. Cine magnetic resonance imaging for evaluation of cardiac structure and flow dynamics in congenital heart disease

    International Nuclear Information System (INIS)

    Cine magnetic resonance imaging (Cine MRI) was performed in 20 patients aged 19 days to 13 years (mean 4.0 years), who had congenital heart disease confirmed at echocardiography or angiography. Prior to cine MRI, gated MRI was performed to evaluate for cardiac structure. Cine MRI was demonstrated by fast low fip angle shot imaging technique with a 30deg flip angle, 15 msec echo time, 30-40 msec pulse repetition time, and 128 x 128 acquisition matrix. Abnormalities of cardiac structure were extremely well defined in all patients by gated MRI. Intracardiac or intravascular blood flow were visualized in 17 (85%) of 20 patients by cine MRI. Left to right shunt flow through ventricular septal defect, atrial septal defect, and endocardial cushion defect were visualized with low signal intensity area. Low intensity jets flow through the site of re-coarctation of the aorta were also visualized. However, the good recording of cine MRI was not obtained because of artifacts in 3 of 20 patients (15%) who had severe congestive heart failure or respiratory arrhythmia. Gated MRI provides excellent visualization of fine structure, and cine MRI can provide high spatial resolution imaging of flow dynamic in a variety of congenital heart disease, noninvasively. (author)

  4. Cardiac assessment by first-pass angioscintigraphy in conjoined thoracopagus twins

    Energy Technology Data Exchange (ETDEWEB)

    Hershlag, A.; Vinograd, I.; Nissan, S.; Atlan, H.

    1985-01-01

    Dynamic computerized heart studies using /sup 99/Tc-DPTA demonstrated a joined heart in conjoined thoracopagus twins. In the case presented, the electrocardiogram, dynamic radioactive study, and the cardiac catheterization all gave basically the same results and correlated well with the postmortem examination. The dynamic study is presented in detail, stressing its advantage as a noninvasive and reliable procedure in the primary cardiac assessment of conjoined twins.

  5. Cardiac assessment by first-pass angioscintigraphy in conjoined thoracopagus twins

    International Nuclear Information System (INIS)

    Dynamic computerized heart studies using 99Tc-DPTA demonstrated a joined heart in conjoined thoracopagus twins. In the case presented, the electrocardiogram, dynamic radioactive study, and the cardiac catheterization all gave basically the same results and correlated well with the postmortem examination. The dynamic study is presented in detail, stressing its advantage as a noninvasive and reliable procedure in the primary cardiac assessment of onjoined twins. (orig.)

  6. In situ cardiac perfusion reveals interspecific variation of intraventricular flow separation in reptiles.

    Science.gov (United States)

    Joyce, William; Axelsson, Michael; Altimiras, Jordi; Wang, Tobias

    2016-07-15

    The ventricles of non-crocodilian reptiles are incompletely divided and provide an opportunity for mixing of oxygen-poor blood and oxygen-rich blood (intracardiac shunting). However, both cardiac morphology and in vivo shunting patterns exhibit considerable interspecific variation within reptiles. In the present study, we develop an in situ double-perfused heart approach to characterise the propensity and capacity for shunting in five reptile species: the turtle Trachemys scripta, the rock python Python sebae, the yellow anaconda Eunectes notaeus, the varanid lizard Varanus exanthematicus and the bearded dragon Pogona vitticeps To simulate changes in vascular bed resistance, pulmonary and systemic afterloads were independently manipulated and changes in blood flow distribution amongst the central outflow tracts were monitored. As previously demonstrated in Burmese pythons, rock pythons and varanid lizards exhibited pronounced intraventricular flow separation. As pulmonary or systemic afterload was raised, flow in the respective circulation decreased. However, flow in the other circulation, where afterload was constant, remained stable. This correlates with the convergent evolution of intraventricular pressure separation and the large intraventricular muscular ridge, which compartmentalises the ventricle, in these species. Conversely, in the three other species, the pulmonary and systemic flows were strongly mutually dependent, such that the decrease in pulmonary flow in response to elevated pulmonary afterload resulted in redistribution of perfusate to the systemic circuit (and vice versa). Thus, in these species, the muscular ridge appeared labile and blood could readily transverse the intraventricular cava. We conclude that relatively minor structural differences between non-crocodilian reptiles result in the fundamental changes in cardiac function. Further, our study emphasises that functionally similar intracardiac flow separation evolved independently in

  7. Beaver Dam Wash Instream Flow Assessment

    OpenAIRE

    United States Bureau of Land Management

    1998-01-01

    This report documents findings from an instream flow assessment conducted by the U.S. Bureau of Land Management (BLM) on Beaver Dam Wash in Mohave County, Arizona. The assessment, which focused on resources located at the mouth of Beaver Dam Wash from 1991 through 1994, provides a scientific basis for relating flowdependent resources to streamflow levels. Natural resource values, methods of data collection and analysis, and flow requirements are presented in this report.

  8. Assessment of hypertrophic cardiomyopathy by ECG gated cardiac computed tomography

    International Nuclear Information System (INIS)

    The applicability of ECG gated cardiac computed tomography (CT) in 12 patients with hypertrophic cardiomyopathy was examined. Six of the 12 patients had hypertrophic obstructive cardiomyopathy, including one patient with mid-ventricular obstruction. Three of the 12 patients had hypertrophic non-obstructive cardiomyopathy, and three had apical hypertrophic cardiomyopathy. The diagnosis of hypertrophic cardiomyopathy was confirmed by the angiocardiogram in all patients. Cardiac CT was performed after intravenous administration of contrast media usually given as a bolus injection. The gantry was set with positive 200 tilt angle. In all patients with hypertrophic obstructive cardiomyopathy except for mid-ventricular obstruction, the hypertrophied interventricular septum in the basal and mid portions was observed, and the left ventricular cavity was narrowed in systole. In a patient with mid-ventricular obstruction, the marked hypertrophied interventricular septum and antero-lateral papillary muscle were observed. In diastole, the left ventricular cavity was narrow and divided into two parts. The apical cavity was completely disappeared in systole. In all patients with hypertrophic non-obstructive cardiomyopathy, the diffuse hypertrophied interventricular septum was observed in diastole. In systole, the apical portion of the left ventricular cavity was markedly narrow and antero-lateral papillary muscle was hypertrophic. In all patients with apical hypertrophic cardiomyopathy, the marked apical hypertrophy of the left ventricular wall was observed in diastole. It is concluded that ECG gated cardiac CT could estimate myocardial wall motion and thickness and differentiate the types of hypertrophic cardiomyopathy each other. (author)

  9. Determinants of Left Ventricular Mass and Hypertrophy in Hemodialysis Patients Assessed by Cardiac Magnetic Resonance Imaging

    OpenAIRE

    Patel, Rajan K.; Oliver, Scott; Patrick B. Mark; Powell, Joanna R.; McQuarrie, Emily P.; Traynor, James P.; Dargie, Henry J; Jardine, Alan G

    2009-01-01

    Background and objectives: Left ventricular hypertrophy (LVH) is an independent risk factor for premature cardiovascular death in hemodialysis (HD) patients and one of the three forms of uremic cardiomyopathy. Cardiovascular magnetic resonance (CMR) is a volume-independent technique to assess cardiac structure. We used CMR to assess the determinants of left ventricular mass (LVM) and LVH in HD patients.

  10. Assessment of cardiac output with transpulmonary thermodilution during exercise in humans

    DEFF Research Database (Denmark)

    Calbet, José A L; Boushel, Robert

    2015-01-01

    The accuracy and reproducibility of transpulmonary thermodilution (TPTd) to assess cardiac output (Q̇) in exercising men was determined using indocyanine green (ICG) dilution as a reference method. TPTd has been utilized for the assessment of Q̇ and preload indexes of global end-diastolic volume...

  11. Echocardiographic abnormalities in the assessment of cardiac organ damage in never-treated hypertensive patients.

    Science.gov (United States)

    Milan, Alberto; Avenatti, Eleonora; Puglisi, Elisabetta; Abram, Sara; Magnino, Corrado; Naso, Diego; Tosello, Francesco; Fabbri, Ambra; Vairo, Alessandro; Mulatero, Paolo; Rabbia, Franco; Veglio, Franco

    2012-01-01

    Hypertension-related cardiac organ damage, other than left ventricular (LV) hypertrophy (LVH), has been described: in particular, concentric remodeling, LV diastolic dysfunction (DD), and left atrial (LA) enlargement are significantly associated with cardiovascular morbility and mortality in different populations. This study evaluated the prevalence of these latter morphofunctional abnormalities, in never-treated essential hypertensive patients and the role of such a serial assessment of hypertensive cardiac damage in improving cardiovascular risk stratification in these patients. A total of 100 never-treated essential hypertensive subjects underwent a complete clinical and echocardiographic evaluation. Left ventricular morphology, systolic and diastolic function, and LA dimension (linear and volume) were evaluated by echocardiography. Left ventricular hypertrophy was present in 14% of the patients, whereas concentric remodeling was present in 25% of the subjects. Among patients free from LV morphology abnormalities, the most frequent abnormality was LA enlargement (global prevalence 57%); the percentage of patients with at least one parameter consistent with DD was 22% in the entire population, but DD was present as the only cardiac abnormality in 1% of our patient. Left atrial volume indexed for body surface area was the most sensitive parameter in identifying hypertension-related cardiac modification. The global prevalence of cardiac alteration reached 73% in never-treated hypertensive patients. Left ventricular remodeling and LA enlargement evaluation may grant a better assessment of cardiac organ damage and cardiovascular risk stratification of hypertensive patients without evidence of LVH after routine examination. PMID:22738434

  12. Utility of cardiac magnetic resonance in assessing right-sided heart failure in sarcoidosis

    International Nuclear Information System (INIS)

    Cardiac involvement in sarcoidosis is associated with a poor prognosis. In patients with right sided heart failure, differentiating between cor-pulmonale, or cardiac sarcoidosis has important implications to management. We present the case of a patient with severe but stable pulmonary sarcoidosis and new onset right sided heart failure despite only mild elevations of pulmonary artery pressure. CMR demonstration of extensive right ventricular fibrosis with associated dilatation and hypokinesis was a key finding for prognosis and management of the patient. Cardiac magnetic resonance (CMR) is the preferred investigation in the diagnosis of cardiac sarcoidosis, allowing assessment of myocardial inflammation and fibrosis, as well as function, in a manner not matched by other technologies

  13. Pulsatile flow simulator for comparison of cardiac output measurements by electromagnetic flow meter and thermodilution.

    Science.gov (United States)

    Jebson, P J; Karkow, W S

    1986-01-01

    This study examined a pulsatile flow simulator for the purpose of evaluating two measurement devices, an extracorporeal flow probe with an electromagnetic flow meter and several thermodilution catheters. We measured the performance of these devices in a range of low to high flows. Using either saline or blood as a perfusate, we obtained different results with these fluids (p less than 0.001). Each catheter behaved in a linear manner, although variation occurred among the catheters with both saline (minimum slope 1.090, maximum slope 1.190) and blood (minimum slope 1.107, maximum slope 1.154). An increase in rate and stroke volumes of the simulator did not demonstrate an identifiable trend in error. The thermodilution catheters were most accurate at 5.0 L/min irrespective of rate, stroke volume, or perfusate used. In contrast, the electromagnetic flow meter accurately represented flows across the wide range of outputs examined (2.4 to 10.7 L/min). (Slope with saline 1.091, slope with blood 1.080) Throughout the range of flow, the flow meter gave a calibration line 5% higher with blood than with saline. The results indicate that accurate measurement of pulsatile blood flow can be achieved in vitro with an electromagnetic flow meter using saline as a perfusate, provided a correction factor is determined and applied to convert values for saline to accurate values for blood. PMID:2940345

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

    NARCIS (Netherlands)

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

    2016-01-01

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

  15. The new criterion for cardiac resynchronization therapy treatment assessed by two channels impedance cardiography

    International Nuclear Information System (INIS)

    The cardiac resynchronization therapy is an effective treatment for systolic failure patients. Independent electrical stimulation of left and right ventricle corrects mechanical ventricular dyssynchrony. About 30–40% treated patients do not respond to therapy. In order to improve clinical outcome authors propose the two channels impedance cardiography for assessment of ventricular dyssynchrony. The proposed method is intended for validation of patients diagnosis and optimization of pacemaker settings for cardiac resynchronization therapy. The preliminary study has showed that bichannel impedance cardiography is a promising tool for assessment of ventricular dyssynchrony.

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

    LENUS (Irish Health Repository)

    Healy, David G

    2012-02-03

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

  17. Evaluation of coronary blood flow velocity during cardiac arrest with circulation maintained through mechanical chest compressions in a porcine model

    Directory of Open Access Journals (Sweden)

    Wagner Henrik

    2011-12-01

    Full Text Available Abstract Background Mechanical chest compressions (CCs have been shown capable of maintaining circulation in humans suffering cardiac arrest for extensive periods of time. Reports have documented a visually normalized coronary blood flow during angiography in such cases (TIMI III flow, but it has never been actually measured. Only indirect measurements of the coronary circulation during cardiac arrest with on-going mechanical CCs have been performed previously through measurement of the coronary perfusion pressure (CPP. In this study our aim was to correlate average peak coronary flow velocity (APV to CPP during mechanical CCs. Methods In a closed chest porcine model, cardiac arrest was established through electrically induced ventricular fibrillation (VF in eleven pigs. After one minute, mechanical chest compressions were initiated and then maintained for 10 minutes upon which the pigs were defibrillated. Measurements of coronary blood flow in the left anterior descending artery were made at baseline and during VF with a catheter based Doppler flow fire measuring APV. Furthermore measurements of central (thoracic venous and arterial pressures were also made in order to calculate the theoretical CPP. Results Average peak coronary flow velocity was significantly higher compared to baseline during mechanical chests compressions and this was observed during the entire period of mechanical chest compressions (12 - 39% above baseline. The APV slowly declined during the 10 min period of mechanical chest compressions, but was still higher than baseline at the end of mechanical chest compressions. CPP was simultaneously maintained at > 20 mmHg during the 10 minute episode of cardiac arrest. Conclusion Our study showed good correlation between CPP and APV which was highly significant, during cardiac arrest with on-going mechanical CCs in a closed chest porcine model. In addition APV was even higher during mechanical CCs compared to baseline. Mechanical

  18. MRI assessment of cardiac tumours: part 2, spectrum of appearances of histologically malignant lesions and tumour mimics

    OpenAIRE

    Hoey, Edward T.D.; Shahid, Muhammad; Ganeshan, Arul; Baijal, Shobhit; Simpson, Helen; Watkin, Richard W.

    2014-01-01

    Cardiac magnetic resonance imaging (MRI) is the reference standard technique for assessment and characterization of a suspected cardiac tumour. It provides an unrestricted field of view, high temporal resolution and non-invasive tissue characterization based on multi-parametric assessment of the chemical micro-environment. Sarcomas account for around 95% of all primary malignant cardiac tumours with lymphoma, and primary pericardial mesothelioma making up most of the remainder of cases. By co...

  19. Short-Term Effects of Transjugular Intrahepatic Shunt on Cardiac Function Assessed by Cardiac MRI: Preliminary Results

    International Nuclear Information System (INIS)

    The purpose of this study was to assess short-term effects of transjugular intrahepatic shunt (TIPS) on cardiac function with cardiac magnetic resonance imaging (MRI) in patients with liver cirrhosis. Eleven patients (six males and five females) with intractable esophageal varices or refractory ascites were imaged with MRI at 1.5 T prior to, within 24 h after, and 4-6 months after TIPS creation (n = 5). Invasive pressures were registered during TIPS creation. MRI consisted of a stack of contiguous slices as well as phase contrast images at all four valve planes and perpendicular to the portal vein. Imaging data were analyzed through time-volume curves and first derivatives. The portoatrial pressure gradient decreased from 19.8 ± 2.3 to 6.6 ± 2.3, accompanied by a nearly two fold increase in central pressures and pulmonary capillary wedge pressure immediately after TIPS creation. Left and right end diastolic volumes and stroke volumes increased by 11, 13, and 24%, respectively (p < 0.001), but dropped back to baseline at follow-up. End systolic volumes remained unchanged. E/A ratios remained within normal range. During follow-up the left ventricular mass was larger than baseline values in all patients, with an average increase of 7.9 g (p < 0.001). In conclusion, the increased volume load shunted to the heart after TIPS creation transiently exceeded the preload reserve of the right and left ventricle, leading to significantly increased pulmonary wedge pressures and persistent enlargement of the left and right atria. Normalization of cardiac dimensions was observed after months together with mild left ventricular hypertrophy.

  20. Performance of automated software in the assessment of segmental left ventricular function in cardiac CT: Comparison with cardiac magnetic resonance

    International Nuclear Information System (INIS)

    To evaluate the accuracy, reliability and time saving potential of a novel cardiac CT (CCT)-based, automated software for the assessment of segmental left ventricular function compared to visual and manual quantitative assessment of CCT and cardiac magnetic resonance (CMR). Forty-seven patients with suspected or known coronary artery disease (CAD) were enrolled in the study. Wall thickening was calculated. Segmental LV wall motion was automatically calculated and shown as a colour-coded polar map. Processing time for each method was recorded. Mean wall thickness in both systolic and diastolic phases on polar map, CCT, and CMR was 9.2 ± 0.1 mm and 14.9 ± 0.2 mm, 8.9 ± 0.1 mm and 14.5 ± 0.1 mm, 8.3 ± 0.1 mm and 13.6 ± 0.1 mm, respectively. Mean wall thickening was 68.4 ± 1.5 %, 64.8 ± 1.4 % and 67.1 ± 1.4 %, respectively. Agreement for the assessment of LV wall motion between CCT, CMR and polar maps was good. Bland-Altman plots and ICC indicated good agreement between CCT, CMR and automated polar maps of the diastolic and systolic segmental wall thickness and thickening. The processing time using polar map was significantly decreased compared with CCT and CMR. Automated evaluation of segmental LV function with polar maps provides similar measurements to manual CCT and CMR evaluation, albeit with substantially reduced analysis time. (orig.)

  1. Performance of automated software in the assessment of segmental left ventricular function in cardiac CT: Comparison with cardiac magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Rui [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Capital Medical University, Department of Radiology, Beijing Anzhen Hospital, Beijing (China); Meinel, Felix G. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Ludwig-Maximilians-University Hospital, Institute for Clinical Radiology, Munich (Germany); Schoepf, U.J. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States); Canstein, Christian [Siemens Medical Solutions USA, Malvern, PA (United States); Spearman, James V. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); De Cecco, Carlo N. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Rome ' ' Sapienza' ' , Departments of Radiological Sciences, Oncology and Pathology, Latina (Italy)

    2015-12-15

    To evaluate the accuracy, reliability and time saving potential of a novel cardiac CT (CCT)-based, automated software for the assessment of segmental left ventricular function compared to visual and manual quantitative assessment of CCT and cardiac magnetic resonance (CMR). Forty-seven patients with suspected or known coronary artery disease (CAD) were enrolled in the study. Wall thickening was calculated. Segmental LV wall motion was automatically calculated and shown as a colour-coded polar map. Processing time for each method was recorded. Mean wall thickness in both systolic and diastolic phases on polar map, CCT, and CMR was 9.2 ± 0.1 mm and 14.9 ± 0.2 mm, 8.9 ± 0.1 mm and 14.5 ± 0.1 mm, 8.3 ± 0.1 mm and 13.6 ± 0.1 mm, respectively. Mean wall thickening was 68.4 ± 1.5 %, 64.8 ± 1.4 % and 67.1 ± 1.4 %, respectively. Agreement for the assessment of LV wall motion between CCT, CMR and polar maps was good. Bland-Altman plots and ICC indicated good agreement between CCT, CMR and automated polar maps of the diastolic and systolic segmental wall thickness and thickening. The processing time using polar map was significantly decreased compared with CCT and CMR. Automated evaluation of segmental LV function with polar maps provides similar measurements to manual CCT and CMR evaluation, albeit with substantially reduced analysis time. (orig.)

  2. Risk Assessment of Mortality Following Intraoperative Cardiac Arrest Using POSSUM and P-POSSUM in Adults Undergoing Non-Cardiac Surgery

    OpenAIRE

    Kim, Shin Hyung; Kil, Hae Keum; Kim, Hye Jin; Koo, Bon-Nyeo

    2015-01-01

    Purpose The Physiological and Operative Severity Score for enUmeration of Mortality and morbidity (POSSUM) and its Portsmouth modification (P-POSSUM) are comprehensive assessment methods for evaluating patient and surgical factors widely used to predict 30-day mortality rates. In this retrospective study, we evaluated the usefulness of POSSUM and P-POSSUM in predicting 30-day mortality after intraoperative cardiac arrests in adult patients undergoing non-cardiac surgery. Materials and Methods...

  3. Assessment of microsphere technique for measurement of capillary blood flow in random skin flaps in pigs

    International Nuclear Information System (INIS)

    In this technical paper, we reviewed the theory and methodology of the radioactive microsphere technique for determination of cardiac output and regional blood flow. Furthermore, we described two experiments conducted to assess this technique for measurement of capillary blood flow in skin-flap research. Our experimental data thus far indicated that the radioactive microsphere technique provided highly reproducible measurements for determination of capillary blood flow in 4 X 10 cm acute and delayed random skin flaps constructed in pigs. The advantages and disadvantages of this laboratory technique were also discussed

  4. Coronary grafts flow and cardiac pacing modalities: how to improve perioperative myocardial perfusion.

    LENUS (Irish Health Repository)

    D'Ancona, Giuseppe

    2012-02-03

    OBJECTIVE: Aim of this study was to investigate modifications of coronary grafts flow during different pacing modalities after CABG. MATERIALS AND METHODS: Two separate prospective studies were conducted in patients undergoing CABG and requiring intraoperative epicardial pacing. In a first study (22 patients) coronary grafts flows were measured during dual chamber pacing (DDD) and during ventricular pacing (VVI). In a second study (10 patients) flows were measured during DDD pacing at different atrio-ventricular (A-V) delay periods. A-V delay was adjusted in 25 ms increments from 25 to 250 ms and flow measurements were performed for each A-V delay increment. A transit time flowmeter was used for the measurements. RESULTS: An average of 3.4 grafts\\/patient were performed. In the first study, average coronary graft flow was 47.4+\\/-20.8 ml\\/min during DDD pacing and 41.8+\\/-18.2 ml\\/min during VVI pacing (P = 0.0004). Furthermore average systolic pressure was 94.3+\\/-10.1 mmHg during DDD pacing and 89.6+\\/-12.2 mmHg during VVV pacing (P = 0.0007). No significant differences in diastolic pressure were recorded during the two different pacing modalities. In the second study, maximal flows were achieved during DDD pacing with an A-V delay of 175 ms (54+\\/-9.6 ml\\/min) and minimal flows were detected at 25 ms A-V delay (38.1+\\/-4.7 ml\\/min) (P=ns). No significant differences in systolic or diastolic blood pressure were noticed during the different A-V delays. CONCLUSION: Grafts flowmetry provides an extra tool to direct supportive measures such as cardiac pacing after CABG. DDD mode with A-V delay around 175 ms. should be preferred to allow for maximal myocardial perfusion via the grafts.

  5. Cardiac abnormalities assessed by non-invasive techniques in patients with newly diagnosed idiopathic inflammatory myopathies

    DEFF Research Database (Denmark)

    Diederichsen, Louise Pyndt; Simonsen, Jane Angel; Diederichsen, Axel Cosmus Pyndt;

    2015-01-01

    inflammatory myopathies (IIM) by means of non-invasive techniques. METHODS: Fourteen patients with IIM (8 polymyositis, 4 dermatomyositis, 2 cancer-associated dermatomyositis) and 14 gender- and age- matched healthy control subjects were investigated. Participant assessments included a cardiac questionnaire...

  6. Sexual Problems in Cardiac Patients How to Assess, When to Refer

    NARCIS (Netherlands)

    Jaarsma, Tiny; Steinke, Elaine E.; Gianotten, Woet L.

    2010-01-01

    It is increasingly realized that discussing sexuality is an important issue in the holistic care for cardiac patients. In this review article, the conditions of a good assessment of sexual problems are identified such as creating an appropriate environment, ensuring confidentiality, and using approp

  7. The utility of cardiac CT beyond the assessment of suspected coronary artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Kakouros, N. [Johns Hopkins Hospital, Baltimore, MD (United States); Giles, J.; Crundwell, N.B. [Conquest Hospital, St Leonards-on-Sea, East Sussex (United Kingdom); McWilliams, E.T.M., E-mail: eric.mcwilliams@esht.nhs.uk [Conquest Hospital, St Leonards-on-Sea, East Sussex (United Kingdom)

    2012-07-15

    Extensive work has been done over recent years to improve the spatial and temporal resolution of electrocardiogram (ECG)-gated cardiac computed tomography (CT). Advances in both hardware and software analysis have enabled the development of non-invasive coronary angiography. However, these high-quality examinations lend themselves to multiple additional applications beyond coronary angiography. In this review, we illustrate and discuss some established and some emerging applications of ECG-gated cardiac CT beyond the assessment of suspected coronary disease, particularly in light of recent recommendations on the appropriate use of this technology.

  8. The utility of cardiac CT beyond the assessment of suspected coronary artery disease

    International Nuclear Information System (INIS)

    Extensive work has been done over recent years to improve the spatial and temporal resolution of electrocardiogram (ECG)-gated cardiac computed tomography (CT). Advances in both hardware and software analysis have enabled the development of non-invasive coronary angiography. However, these high-quality examinations lend themselves to multiple additional applications beyond coronary angiography. In this review, we illustrate and discuss some established and some emerging applications of ECG-gated cardiac CT beyond the assessment of suspected coronary disease, particularly in light of recent recommendations on the appropriate use of this technology.

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

    DEFF Research Database (Denmark)

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

    2016-01-01

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

  10. Design and testing of an MRI-compatible cycle ergometer for non-invasive cardiac assessments during exercise

    OpenAIRE

    Gusso Silmara; Salvador Carlo; Hofman Paul; Cutfield Wayne; Baldi James C; Taberner Andrew; Nielsen Poul

    2012-01-01

    Abstract Background Magnetic resonance imaging (MRI) is an important tool for cardiac research, and it is frequently used for resting cardiac assessments. However, research into non-pharmacological stress cardiac evaluation is limited. Methods We aimed to design a portable and relatively inexpensive MRI cycle ergometer capable of continuously measuring pedalling workload while patients exercise to maintain target heart rates. Results We constructed and tested an MRI-compatible cycle ergometer...

  11. Prospective evaluation of stress myocardial perfusion imaging for pre-operative cardiac risk assessment

    International Nuclear Information System (INIS)

    Full text: A prospective evaluation of patients who underwent stress myocardial perfusion imaging (MPI) to assess preoperative cardiac risk was undertaken. At the time of the scan patients were classified into 4 Clinical Risk groups (CR) based on known clinical data. On completion of the scan, the patient was then categorised into 4 Scan based Risk groups (SR), incorporating size of perfusion deficit, single versus multi-vessel disease and ejection fraction. Surgery at Austin and Repatriation Medical Centre within 6 months of scan and complications were identified using the hospital medical database. Major early cardiac events coded were death (cardiac related), myocardial infarction, unstable angina, acute pulmonary oedema, cardiac arrest, and urgent revascularisation. 208 patients have reached 6 months post-MPI scan. Of these 119 (57%) were identified as having surgery. Of the Scan Risk groups, 63% of normal, 57% of increased, and 47% of high and very high groups have had surgery. An abnormal scan is associated with a three-fold risk of cardiac complication (3.5% vs 11.3%). This is lower than most previous reports and may be due to higher representation of low risk surgical procedures (14% in this series), improved peri-operative care and/or the test result influence on management (suggested by decreasing surgical rate as SR estimate rose). Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

  12. Assessment of factors that influence weaning from long-term mechanical ventilation after cardiac surgery

    Directory of Open Access Journals (Sweden)

    Emília Nozawa

    2003-03-01

    Full Text Available OBJECTIVE: To analyze parameters of respiratory system mechanics and oxygenation and cardiovascular alterations involved in weaning tracheostomized patients from long-term mechanical ventilation after cardiac surgery. METHODS: We studied 45 patients in their postoperative period of cardiac surgery, who required long-term mechanical ventilation for more than 10 days and had to undergo tracheostomy due to unsuccessful weaning from mechanical ventilation. The parameters of respiratory system mechanics, oxigenation and the following factors were analyzed: type of surgical procedure, presence of cardiac dysfunction, time of extracorporeal circulation, and presence of neurologic lesions. RESULTS: Of the 45 patients studied, successful weaning from mechanical ventilation was achieved in 22 patients, while the procedure was unsuccessful in 23 patients. No statistically significant difference was observed between the groups in regard to static pulmonary compliance (p=0.23, airway resistance (p=0.21, and the dead space/tidal volume ratio (p=0.54. No difference was also observed in regard to the variables PaO2/FiO2 ratio (p=0.86, rapid and superficial respiration index (p=0.48, and carbon dioxide arterial pressure (p=0.86. Cardiac dysfunction and time of extracorporeal circulation showed a significant difference. CONCLUSION: Data on respiratory system mechanics and oxygenation were not parameters for assessing the success or failure. Cardiac dysfunction and time of cardiopulmonary bypass, however, significantly interfered with the success in weaning patients from mechanical ventilation.

  13. Cardiac surgery during pregnancy: Continuous fetal monitoring using umbilical artery Doppler flow velocity indices

    Directory of Open Access Journals (Sweden)

    Manisha Mishra

    2014-01-01

    Full Text Available The fetal death rate associated with cardiac surgery with cardiopulmonary bypass (CPB is as high as 9.5-29%. We report continuous monitoring of fetal heart rate and umbilical artery flow-velocity waveforms by transvaginal ultrasonography and their analyses in relation to events of the CPB in two cases in second trimester of pregnancy undergoing mitral valve replacement. Our findings suggest that the transition of circulation from corporeal to extracorporeal is the most important event during surgery; the associated decrease in mean arterial pressure (MAP at this stage potentially has deleterious effects on the fetus, which get aggravated with the use of vasopressors. We suggest careful management of CPB at this stage, which include partial controlled CPB at initiation and gradual transition to full CPB; this strategy maintains high MAP and avoids the use of vasopressors. Maternal and fetal monitoring can timely recognize the potential problems and provide window for the required treatment.

  14. Assessment and Utility of Frailty Measures in Critical Illness, Cardiology, and Cardiac Surgery.

    Science.gov (United States)

    Rajabali, Naheed; Rolfson, Darryl; Bagshaw, Sean M

    2016-09-01

    Frailty is a clearly emerging theme in acute care medicine, with obvious prognostic and health resource implications. "Frailty" is a term used to describe a multidimensional syndrome of loss of homeostatic reserves that gives rise to a vulnerability to adverse outcomes after relatively minor stressor events. This is conceptually simple, yet there has been little consensus on the operational definition. The gold standard method to diagnose frailty remains a comprehensive geriatric assessment; however, a variety of validated physical performance measures, judgement-based tools, and multidimensional scales are being applied in critical care, cardiology, and cardiac surgery settings, including open cardiac surgery and transcatheter aortic value replacement. Frailty is common among patients admitted to the intensive care unit and correlates with an increased risk for adverse events, increased resource use, and less favourable patient-centred outcomes. Analogous findings have been described across selected acute cardiology and cardiac surgical settings, in particular those that commonly intersect with critical care services. The optimal methods for screening and diagnosing frailty across these settings remains an active area of investigation. Routine assessment for frailty conceivably has numerous purported benefits for patients, families, health care providers, and health administrators through better informed decision-making regarding treatments or goals of care, prognosis for survival, expectations for recovery, risk of complications, and expected resource use. In this review, we discuss the measurement of frailty and its utility in patients with critical illness and in cardiology and cardiac surgery settings. PMID:27476983

  15. The Use of Standard Gastrointestinal Endoscopic Ultrasound to Assess Cardiac Anatomy.

    Science.gov (United States)

    Sentissi, Kinza; Sawhney, Mandeep S; Pleskow, Douglas; Sepe, Paul; Mella, Jose M; Kwittken, Benjamin; Ketwaroo, Gyanprakash; Subramaniam, Balachundhar

    2016-09-01

    In this prospective observational study, conducted at an academic medical center, we evaluated the feasibility of performing a basic transesophageal echocardiography (TEE) examination using endoscopic ultrasound (EUS) technology to determine what cardiac structures could be assessed. This may be potentially beneficial during hemodynamic emergencies in the endoscopy suite resulting from hypovolemia, depressed ventricular function, aortic dissection, pericardial effusions, or aortic stenosis. Of the 20 patients enrolled, 18 underwent EUS with a linear echoendoscope for standard clinical indications followed by a cardiac assessment performed under the guidance of a TEE-certified cardiac anesthesiologist. Eight of the 20 standard views of cardiovascular structures per the 1999 American Society of Echocardiography/Society of Cardiovascular Anesthesiologists guidelines for TEE could be obtained using the linear echoendoscope. The following cardiac valvular structures were visualized: aortic valve (100%), mitral valve (100%), tricuspid valve (33%), and pulmonic valve (11%). Left ventricular and right ventricular systolic function could be assessed in 89% and 67% of patients, respectively. Other structures such as the ascending and descending aorta, pericardium, left atrial appendage, and interatrial septum were identified in 100% of patients. Doppler-dependent functions could not be assessed. Given that the EUS images were not directly compared with TEE in these patients, we cannot comment definitively on the quality of these assessments and further studies would need to be performed to make a formal comparison. Based on this study, EUS technology can consistently assess the mitral valve, aortic valve, aorta, pericardium, and left ventricular function. Given its limitations, EUS technology, although not a substitute for formal echocardiography, could be a helpful early diagnostic tool in an emergency setting. PMID:27541718

  16. The assessment of cardiac autonomic functions in adolescents with a family history of premature atherosclerosis

    Science.gov (United States)

    Dursun, Huseyin; Kilicaslan, Baris; Aydin, Mehmet

    2014-01-01

    OBJECTIVES: Subclinical atherosclerosis has been recently detected in adolescents with a family history of premature atherosclerosis. However, no studies in the literature have assessed the cardiac autonomic functions of these adolescents. The aim of this study was to evaluate the cardiac autonomic functions of adolescents with a family history of premature atherosclerosis compared with those of age- and gender-matched adolescents without a family history of atherosclerosis. METHOD: We evaluated the cardiac autonomic functions of 36 adolescents with a family history of premature atherosclerosis (Group 1) and compared them with those of 31 age- and gender-matched adolescents whose parents did not have premature atherosclerosis (Group 2). Twenty-four-hour time domain (standard deviation of all normal sinus RR intervals [SDNN], standard deviation of the mean of normal RR intervals in each 5-minute segment [SDANN], root-mean-square differences in successive RR intervals) and frequency domain (very low frequency, low frequency, high frequency, low frequency/high frequency) parameters of heart rate variability were used for the evaluation of cardiac autonomic functions. RESULTS: There were no differences in the time and frequency domain parameters of heart rate variability between the two groups. Heart rate was negatively correlated with SDNN (r = -0.278, p = 0.035), while age was significantly correlated with root-mean-square differences in successive RR intervals, high frequency, low frequency and low frequency/high frequency (r = -0.264, -0.370, 0.265 and 0.374, respectively; p<0.05 for all). CONCLUSION: We found that the cardiac autonomic functions of adolescents with a family history of premature atherosclerosis were not different compared with those of adolescents without a positive family history of premature atherosclerosis. It appears that subclinical atherosclerosis does not reach a critical value such that it can alter cardiac autonomic functions

  17. Reliability assessment of tunneling flow charts

    International Nuclear Information System (INIS)

    When driving horizontal workings of different kinds it is typical to reserve excessive redundant equipment. However, the lack of resources (facilities, people) and poor management don't ensure goal achievement [3]. The paper presents reliability assessment method of tunneling with the help of mathematical modeling. The mathematical model is developed on the basis of factual data of tunneling conditions and no-failure operation probabilities of the flow chart elements are estimated. The method of reliability assessment allows identifying organizational, technological and technical elements of the reserves to increases drive efficiency and improve feasibility characteristics

  18. Reliability assessment of tunneling flow charts

    Science.gov (United States)

    Antropova, N. A.; Krets, V. G.; Luk'yanov, V. G.; Baranova, A. V.

    2015-02-01

    When driving horizontal workings of different kinds it is typical to reserve excessive redundant equipment. However, the lack of resources (facilities, people) and poor management don't ensure goal achievement [3]. The paper presents reliability assessment method of tunneling with the help of mathematical modeling. The mathematical model is developed on the basis of factual data of tunneling conditions and no-failure operation probabilities of the flow chart elements are estimated. The method of reliability assessment allows identifying organizational, technological and technical elements of the reserves to increases drive efficiency and improve feasibility characteristics.

  19. Assessing the blalock-hanlon atrioseptectomy at cardiac catheterization.

    Science.gov (United States)

    Clark, E B; Rosenquist, G C

    1977-01-01

    Blalock-Hanlon atrial septectomy (BH) is performed to increase systemic and pulmonary venous mixing at the atrial level. Failure of clinical improvement may be related to inadequate intraatrial communication. A simple catheterization technique employing a balloon catheter is used to assess the presence or absence of the limbus of the foramen ovale following BH, since persistence of the limbus of the fossa ovalis after BH is associated with significantly smaller percentage of communication (atrial communication area/total atrial area). PMID:603909

  20. Assessment of cardiac morphology and ventricular function in healthy Chinese individuals using MRI

    International Nuclear Information System (INIS)

    Objective: To investigate reproducibility of cardiac MRI for assessment of cardiac morphology and ventricular function in selected normal Chinese Han population. Methods: Two hundred and sixty-nine normal volunteers underwent cardiac MRI using a 1.5 T MR system. HASTE and steady state free precession imaging were performed with long and short axis images and cine mode through the ventricle with wireless vector cardiac gating. The images were reviewed by two independent observers. The dimensions of cardiac chambers and ventricular function including ejection fraction (EF), end diastolic volume (EDV) , end systolic volume (ESV) and myocardial mass were evaluated. The data between male and female were compared by using two-tailed unpaired t test. Results: Total imaging time was (15±3) min. The anteroposterior diameter of the left atrium was (2.87±0.77) cm, the right atrial diameter perpendicular to the atrial septum was (3.61±0.57) cm, the end diastolic diameter of the left ventricle was (4.97± 0.52) cm, the end diastolic diameter of the right ventricle was (2.65±0.48) cm. On the left ventricle, EF was (60.62±7.08)%, EDV was (115.37±26.71) ml, ESV was (46.02±15.72) ml and LV mass was (82.97±24.03) g. On the right ventricle, EF was (47.73±6.50)%, EDV was (128.27±32.16) ml, ESV was (67.7±21.07) ml and RV mass was (48.24±13.42) g. There were no statistically significant differences in LVESV (P=0.144), LVEDV index (P=0.714), LVESV index (P=0.113), LVCI (P=0.199), RVEF (P=0.296) and RV mass (P=0.093), and statistically significant differences in other cardiac parameters between male and female. Conclusion: Cardiac MRI can provide useful information about cardiac function and morphology with a high level of reproducibility in normal Chinese Han population. (authors)

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

    International Nuclear Information System (INIS)

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

  2. Cardiac Risk Assessment, Morbidity Prediction, and Outcome in the Vascular Intensive Care Unit.

    LENUS (Irish Health Repository)

    Dover, Mary

    2013-09-17

    Objectives: The aim of this study is to examine the predictive value of the Lee revised cardiac risk index (RCRI) for a standard vascular intensive care unit (ICU) population as well as assessing the utility of transthoracic echocardiography and the impact of prior coronary artery disease (CAD) and coronary revascularization on patient outcome. Design: This is a retrospective review of prospectively maintained Vascubase and prospectively collected ICU data. Materials and Methods: Data from 363 consecutive vascular ICU admissions were collected. Findings were used to calculate the RCRI, which was then correlated with patient outcomes. All patients were on optimal medical therapy (OMT) in the form of cardioselective β-blocker, aspirin, statin, and folic acid. Results: There was no relationship found between a reduced ejection fraction and patient outcome. Mortality was significantly increased for patients with left ventricular hypertrophy (LVH) as identified on echo (14.9% vs 6.5%, P = .028). The overall complication rates were significantly elevated for patients with valvular dysfunction. Discrimination for the RCRI on receiver-operating characteristic analysis was poor, with an area under the receiver-operating characteristic curve of .621. Model calibration was reasonable with an Hosmer-Lemeshow Ĉ statistic of 2.726 (P = .256). Of those with known CAD, 41.22% of the patients receiving best medical treatment developed acute myocardial infarction (AMI) compared to 35.3% of those who previously underwent percutaneous cardiac intervention and 23.5% of those who had undergone coronary artery bypass grafting. There was 3-fold increase in major adverse clinical events in patients with troponin rise and LVH. Conclusions: The RCRI\\'s discriminatory capacity is low, and this raises difficulties in assessing cardiac risk in patients undergoing vascular intervention. The AMI is highest in the OMT group without prior cardiac intervention, which mandates protocols to

  3. Study progress of cardiac MRI technology in assessment of myocardial viability after myocardial infarction

    International Nuclear Information System (INIS)

    Acute myocardial infarction (AMI) is one of the most common diseases that cause disability and death around the world. Correctly and effectively assessing the myocardial viability after myocardial infarction can reduce the disabled rate and mortality rate. At present, many methods could be used to assess myocardial viability. The cardiac magnetic resonance imaging (CMR) technology has a lot of advantages compared to other methods. In this paper, we reviewed the research progress of CMR in assessment of myocardial viability after myocardial infarction, and compared CMR with other technologies. (authors)

  4. The PhysioFlow thoracic impedancemeter is not valid for the measurements of cardiac hemodynamic parameters in chronic anemic patients.

    Directory of Open Access Journals (Sweden)

    Pascal Bogui

    Full Text Available The aim of the present study was to test the validity of the transthoracic electrical bioimpedance method PhysioFlow® to measure stroke volume in patients with chronic anemia. Stroke volume index (SVI, as well as cardiac index (CI obtained by transthoracic electrical bioimpedance method and doppler echocardiography were compared in healthy subjects (n = 25 and patients with chronic anemia (i.e. mainly with sickle cell anemia; n = 32, at rest. While doppler echocardiography was able to detect difference in SVI between the two populations, the Physioflow® failed to detect any difference. Bland & Altman analyses have demonstrated no interchangeability between the two methods to assess CI and SVI in anemic patients and healthy subjects. While doppler echocardiography displayed a good concordance for SVI results with those obtained in the literature for anemic patients, the Physioflow® did not. Finally, in contrast to doppler echocardiography: 1 the CI obtained with the Physioflow® was not correlated with the hemoglobin level and 2 the stroke volume determined by the Physioflow® was highly influenced by body surface area. In conclusion, our findings indicate that the Physioflow® device is inaccurate for the measurement of SVI and CI in patients with chronic anemia and has a poor accuracy for the measurement of these parameters in African healthy subjects.

  5. Cardiac pathologies in female carriers of Duchenne muscular dystrophy assessed by cardiovascular magnetic resonance imaging

    International Nuclear Information System (INIS)

    Duchenne muscular dystrophy (DMD) is the most common and severe dystrophinopathy. DMD carriers rarely present with clinical symptoms, but may suffer from cardiac involvement. Because echocardiographic findings are inconsistent and cardiac magnetic resonance imaging (CMRI) data are limited, this study sought to investigate asymptomatic carriers for cardiac abnormalities using CMRI. Fifteen genetically confirmed DMD carriers (age, 32.3 ± 10.2 years) were prospectively examined on a 1.5T MR system. Cine, T2, and late-gadolinium-enhanced (LGE) images were acquired, and were evaluated in consensus by two experienced readers. Left ventricular (LV) parameters were analysed semiautomatically, normalized to BSA. Normalized LV end-diastolic volume was increased in 7 % (73.7 ± 16.8 ml/m2; range, 48-116 ml/m2) and normalized LV end-systolic volume in 20 % (31.5 ± 13.3 ml/m2; range, 15-74 ml/m2). EF was reduced in 33 % (58.4 ± 7.6 %; range, 37-69 %) and normalized LV myocardial mass in 80 % (40.5 ± 6.8 g/m2; range, 31-55 g/m2). In 80 %, regional myocardial thinning was detected in more than one segment. In 13 % and 40 %, apical-lateral accentuation of LV non-compaction was present. LGE was found in 60 % (midmyocardial inferolateral accentuation). Given the high frequency of cardiac pathologies detected by CMRI, regular cardiac risk assessment is advisable for DMD carriers. Besides clinical examination, CMRI is an excellent tool for this purpose. (orig.)

  6. Cardiac pathologies in female carriers of Duchenne muscular dystrophy assessed by cardiovascular magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Schelhorn, Juliane; Schemuth, Haemi; Nensa, Felix; Nassenstein, Kai; Forsting, Michael; Schlosser, Thomas [University Hospital Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Schoenecker, Anne; Neudorf, Ulrich [University Hospital Essen, Department of Pediatric Cardiology, Essen (Germany); Schara, Ulrike [University Hospital Essen, Department of Pediatric Neurology, Essen (Germany)

    2015-10-15

    Duchenne muscular dystrophy (DMD) is the most common and severe dystrophinopathy. DMD carriers rarely present with clinical symptoms, but may suffer from cardiac involvement. Because echocardiographic findings are inconsistent and cardiac magnetic resonance imaging (CMRI) data are limited, this study sought to investigate asymptomatic carriers for cardiac abnormalities using CMRI. Fifteen genetically confirmed DMD carriers (age, 32.3 ± 10.2 years) were prospectively examined on a 1.5T MR system. Cine, T2, and late-gadolinium-enhanced (LGE) images were acquired, and were evaluated in consensus by two experienced readers. Left ventricular (LV) parameters were analysed semiautomatically, normalized to BSA. Normalized LV end-diastolic volume was increased in 7 % (73.7 ± 16.8 ml/m{sup 2}; range, 48-116 ml/m{sup 2}) and normalized LV end-systolic volume in 20 % (31.5 ± 13.3 ml/m{sup 2}; range, 15-74 ml/m{sup 2}). EF was reduced in 33 % (58.4 ± 7.6 %; range, 37-69 %) and normalized LV myocardial mass in 80 % (40.5 ± 6.8 g/m{sup 2}; range, 31-55 g/m{sup 2}). In 80 %, regional myocardial thinning was detected in more than one segment. In 13 % and 40 %, apical-lateral accentuation of LV non-compaction was present. LGE was found in 60 % (midmyocardial inferolateral accentuation). Given the high frequency of cardiac pathologies detected by CMRI, regular cardiac risk assessment is advisable for DMD carriers. Besides clinical examination, CMRI is an excellent tool for this purpose. (orig.)

  7. Computerized assessment of motion-contaminated calcified plaques in cardiac multidetector CT

    International Nuclear Information System (INIS)

    An automated method for evaluating the image quality of calcified plaques with respect to motion artifacts in noncontrast-enhanced cardiac computed tomography (CT) images is introduced. This method involves using linear regression (LR) and artificial neural network (ANN) regression models for predicting two patient-specific, region-of-interest-specific, reconstruction-specific and temporal phase-specific image quality indices. The first is a plaque motion index, which is derived from the actual trajectory of the calcified plaque and is represented on a continuous scale. The second is an assessability index, which reflects the degree to which a calcified plaque is affected by motion artifacts, and is represented on an ordinal five-point scale. Two sets of assessability indices were provided independently by two radiologists experienced in evaluating cardiac CT images. Inputs for the regression models were selected from 12 features characterizing the dynamic, morphological, and intensity-based properties of the calcified plaques. Whereas LR-velocity (LR-V) used only a single feature (three-dimensional velocity), the LR-multiple (LR-M) and ANN regression models used the same subset of these 12 features selected through stepwise regression. The regression models were parameterized and evaluated using a database of simulated calcified plaque images from the dynamic NCAT phantom involving nine heart rate/multi-sector gating combinations and 40 cardiac phases covering two cardiac cycles. Six calcified plaques were used for the plaque motion indices and three calcified plaques were used for both sets of assessability indices. In one configuration, images from the second cardiac cycle were used for feature selection and regression model parameterization, whereas images from the first cardiac cycle were used for testing. With this configuration, repeated measures concordance correlation coefficients (CCCs) and associated 95% confidence intervals for the LR-V, LR-M, and ANN

  8. Quantification of chemotaxis during pediatric cardiac surgery by flow and laser scanning cytometry

    Science.gov (United States)

    Tarnok, Attila; Schmid, Joerg W.; Osmancik, Pavel; Lenz, Dominik; Pipek, Michal; Hambsch, Joerg; Gerstner, Andreas O.; Schneider, Peter

    2002-05-01

    Cardiac surgery with cardiopulmonary bypass (CPB) alters the leukocyte composition of the peripheral blood (PB). This response contributes to the sometimes adverse outcome with capillary leakage. Migration of activated cells to sites of inflammation, driven by chemokines is part of this response. In order to determine the chemotactic activity of patients serum during and after surgery we established an assay for PB leukocytes (PBL). PBL from healthy donors were isolated and 250,000 cells were placed into a migration chamber separated by a filter from a second lower chamber filled with patient serum. After incubation cells from top and bottom chamber were removed and stained with a cocktail of monoclonal antibodies for leukocyte subsets and analyzed on a flow cytometer (FCM). Cells at the bottom of the filter belong to the migrating compartment and were quantified by LSC after staining of nucleated cells. Increased chemotactic activity started at onset of anaesthesia followed by a phase of low activity immediately after surgery and a second phase of a high post-operative activity. The in vitro results correlated with results obtained by immunopenotyping of circulating PBL. Manipulation of the chemokine pattern might prove beneficial to prevent extravasation of cells leading to tissue damage. In chemotaxis assays with low amount of available serum the combined use of FCM and Laser Scanning LSC proved as an appropriate analytical tool.

  9. Pain after Cardiac Surgery: A Review of the Assessment and Management

    Directory of Open Access Journals (Sweden)

    Parizad Razieh

    2014-10-01

    Full Text Available Objective: Surgery is among the causes of acute pain. One of the major problems of patients after surgical procedures is postoperative pain. Annually, millions of people throughout the world undergo surgery and experience different intensities of postoperative pain. Due to physiological changes and given the stability of the heart and lung, the management and control of pain is rarely considered as a priority in the care of patients after cardiac surgery. Cardiac surgical patients experience pain due to the surgical incision and between the ribs nerve injury created during the course of the surgery, and irritation and inflammation of the pleura by catheters. Control and management of pain in intensive care units (ICU are the main tasks in nursing care. The purpose of this review study was the investigation, assessment, and management of pain in patients after cardiac surgery. Materials and Methods: In this study, the literature available on Magiran, Google Scholar, ScienceDirect, and PubMed were collected, and after reviewing, the relevant literature was studied. Results: Although pain is one of the major stressors in patients undergoing surgery, the measures taken for the treatment and care of these patients are associated with experiencing pain. In this regard, all the resources have emphasized the using of guidelines and tools to assess patients' pain. However, in cardiac surgery patients, sufficient attention is not paid to pain control. Patients reported poorly controlled pain and experiences of moderate to severe pain after surgery. Conclusion: Pain is a subjective experience, and in patients who cannot report their pain, it should be considered important. According to numerous studies, pain control is not performed in ICUs. Thus, efforts should be made for appropriate control and reduction of pain, use of valid methods to determine and control pain, and improvement of the quality of the programs.

  10. The PhysioFlow Thoracic Impedancemeter Is Not Valid for the Measurements of Cardiac Hemodynamic Parameters in Chronic Anemic Patients

    OpenAIRE

    Bogui, Pascal; Balayssac-Siransy, Edwige; Connes, Philippe; Tuo, Nalourgo; Ouattara, Soualiho; Pichon, Aurélien; Dah, Cyrille Serges

    2013-01-01

    The aim of the present study was to test the validity of the transthoracic electrical bioimpedance method PhysioFlow® to measure stroke volume in patients with chronic anemia. Stroke volume index (SVI), as well as cardiac index (CI) obtained by transthoracic electrical bioimpedance method and doppler echocardiography were compared in healthy subjects (n = 25) and patients with chronic anemia (i.e. mainly with sickle cell anemia; n = 32), at rest. While doppler echocardiography was able to det...

  11. Renal Doppler and Novel Biomarkers to Assess Acute Kidney Injury in a Swine Model of Ventricular Fibrillation Cardiac Arrest

    Institute of Scientific and Technical Information of China (English)

    Xue Mei; Chen-Chen Hang; Shuo Wang; Chun-Sheng Li; Ze-Xing Yu

    2015-01-01

    Background: Majority of the research on cardiac arrest (CA) have focused on post-CA brain injury and myocardial dysfunction, the renal dysfunction and acute kidney injury (AKI) in other critical illnesses after CA have not been well described.This study was designed to assess AKI with renal Doppler and novel AKI biomarkers in a swine model ofventricular fibrillation cardiac arrest (VFCA).Methods: Thirty healthy piglets were divided into VFCA group (n =22) and Sham group (n =8) in a blinded manner.Mean arterial pressure, heart rate, and cardiac output were recorded continuously.Cardiac arrest (CA) was induced by programmed electric stimulation in the VFCA group, and then cardiopulmonary resuscitation was performed.Twenty piglets retumed of spontaneous circulation (ROSC) and received intensive care.Blood and urine samples were collected for AKI biomarkers testing, and Color Doppler flow imaging was performed at baseline, 6 h, 12 h, and 24 h,respectively after ROSC.At ROSC 24 h, the animals were sacrificed and a semi-quantitative evaluation of pathologic kidney injury was performed.Results: In the VFCA group, corrected resistive index (cRI) increased from 0.47 ± 0.03 to 0.64 ± 0.06, and pulsatility index (PI) decreased from 0.82 ± 0.03 to 0.68 ± 0.04 after ROSC.Cystatin C (CysC) in both serum and urine samples increased at ROSC 6 h, but neutrophil gelatinase-associated lipocalin (NGAL) in serum increased to 5.34 ± 1.68 ng/ml at ROSC 6 h, and then decreased to 3.16 ± 0.69 ng/ml at ROSC 24 h while CysC increasing constantly.According to the renal histopathology, 18 of 20 animals suffered from kidney injury.The grade of renal injury was highly correlated with RI, cRI, NGAL, and CysC.Linear regression equation was established: Grade of renal injury =0.002 × serum CysC + 6.489 × PI + 4.544 × cRI-8.358 (r2 =0.698, F =18.506, P < 0.001).Conclusions: AKI is common in post-CA syndrome.Renal Doppler and novel AKI biomarkers in serum and urine are of significant

  12. Comparison of simultaneous and sequential SPECT imaging for discrimination tasks in assessment of cardiac defects

    International Nuclear Information System (INIS)

    Simultaneous rest perfusion/fatty-acid metabolism studies have the potential to replace sequential rest/stress perfusion studies for the assessment of cardiac function. Simultaneous acquisition has the benefits of increased signal and lack of need for patient stress, but is complicated by cross-talk between the two radionuclide signals. We consider a simultaneous rest 99mTc-sestamibi/123I-BMIPP imaging protocol in place of the commonly used sequential rest/stress 99mTc-sestamibi protocol. The theoretical precision with which the severity of a cardiac defect and the transmural extent of infarct can be measured is computed for simultaneous and sequential SPECT imaging, and their performance is compared for discriminating (1) degrees of defect severity and (2) sub-endocardial from transmural defects. We consider cardiac infarcts for which reduced perfusion and metabolism are observed. From an information perspective, simultaneous imaging is found to yield comparable or improved performance compared with sequential imaging for discriminating both severity of defect and transmural extent of infarct, for three defects of differing location and size.

  13. Comparison of simultaneous and sequential SPECT imaging for discrimination tasks in assessment of cardiac defects

    Science.gov (United States)

    Trott, CM; Ouyang, J; El Fakhri, G

    2011-01-01

    Simultaneous rest perfusion/fatty-acid metabolism studies have the potential to replace sequential rest/stress perfusion studies for the assessment of cardiac function. Simultaneous acquisition has the benefits of increased signal and lack of need for patient stress, but is complicated by cross-talk between the two radionuclide signals. We consider a simultaneous rest 99mTc-sestamibi/123I-BMIPP imaging protocol in place of the commonly-used sequential rest/stress 99mTc-sestamibi protocol. The theoretical precision with which the severity of a cardiac defect and the transmural extent of infarct can be measured is computed for simultaneous and sequential SPECT imaging, and their performance is compared for discriminating (1) degrees of defect severity, and (2) sub-endocardial from transmural defects. We consider cardiac infarcts, for which reduced perfusion and metabolism are observed. From an information perspective, simultaneous imaging is found to yield comparable or improved performance compared with sequential imaging for discriminating both severity of defect and transmural extent of infarct, for three defects of differing location and size. PMID:21048290

  14. Comparison of simultaneous and sequential SPECT imaging for discrimination tasks in assessment of cardiac defects

    Energy Technology Data Exchange (ETDEWEB)

    Trott, C M; Ouyang, J; El Fakhri, G, E-mail: ctrott@pet.mgh.harvard.ed [Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit St, Boston, MA 02114 (United States)

    2010-11-21

    Simultaneous rest perfusion/fatty-acid metabolism studies have the potential to replace sequential rest/stress perfusion studies for the assessment of cardiac function. Simultaneous acquisition has the benefits of increased signal and lack of need for patient stress, but is complicated by cross-talk between the two radionuclide signals. We consider a simultaneous rest {sup 99m}Tc-sestamibi/{sup 123}I-BMIPP imaging protocol in place of the commonly used sequential rest/stress {sup 99m}Tc-sestamibi protocol. The theoretical precision with which the severity of a cardiac defect and the transmural extent of infarct can be measured is computed for simultaneous and sequential SPECT imaging, and their performance is compared for discriminating (1) degrees of defect severity and (2) sub-endocardial from transmural defects. We consider cardiac infarcts for which reduced perfusion and metabolism are observed. From an information perspective, simultaneous imaging is found to yield comparable or improved performance compared with sequential imaging for discriminating both severity of defect and transmural extent of infarct, for three defects of differing location and size.

  15. Motion corrected LV quantification based on 3D modelling for improved functional assessment in cardiac MRI

    Science.gov (United States)

    Liew, Y. M.; McLaughlin, R. A.; Chan, B. T.; Aziz, Y. F. Abdul; Chee, K. H.; Ung, N. M.; Tan, L. K.; Lai, K. W.; Ng, S.; Lim, E.

    2015-04-01

    Cine MRI is a clinical reference standard for the quantitative assessment of cardiac function, but reproducibility is confounded by motion artefacts. We explore the feasibility of a motion corrected 3D left ventricle (LV) quantification method, incorporating multislice image registration into the 3D model reconstruction, to improve reproducibility of 3D LV functional quantification. Multi-breath-hold short-axis and radial long-axis images were acquired from 10 patients and 10 healthy subjects. The proposed framework reduced misalignment between slices to subpixel accuracy (2.88 to 1.21 mm), and improved interstudy reproducibility for 5 important clinical functional measures, i.e. end-diastolic volume, end-systolic volume, ejection fraction, myocardial mass and 3D-sphericity index, as reflected in a reduction in the sample size required to detect statistically significant cardiac changes: a reduction of 21-66%. Our investigation on the optimum registration parameters, including both cardiac time frames and number of long-axis (LA) slices, suggested that a single time frame is adequate for motion correction whereas integrating more LA slices can improve registration and model reconstruction accuracy for improved functional quantification especially on datasets with severe motion artefacts.

  16. A novel approach for assessing cardiac fibrosis using label-free second harmonic generation.

    Science.gov (United States)

    Martin, Tamara P; Norris, Greg; McConnell, Gail; Currie, Susan

    2013-12-01

    To determine whether second harmonic generation (SHG) can be used as a novel and improved label-free technique for detection of collagen deposition in the heart. To verify whether SHG will allow accurate quantification of altered collagen deposition in diseased hearts following hypertrophic remodelling. Minimally invasive transverse aortic banding (MTAB) of mouse hearts was used to generate a reproducible model of cardiac hypertrophy. Physiological and functional assessment of hypertrophic development was performed using echocardiography and post-mortem analysis of remodelled hearts. Cardiac fibroblasts were isolated from sham-operated and hypertrophied hearts and proliferation rates compared. Multi-photon laser scanning microscopy was used to capture both two-photon excited autofluorescence (TPEF) and SHG images simultaneously in two channels. TPEF images were subtracted from SHG images and the resulting signal intensities from ventricular tissue sections were calculated. Traditional picrosirius red staining was used to verify the suitability of the SHG application. MTAB surgery induced significant hypertrophic remodelling and increased cardiac fibroblast proliferation. A significant increase in the density of collagen fibres between hypertrophic and control tissues (p < 0.05) was evident using SHG. Similar increases and patterns of staining were observed using parallel traditional picrosirius red staining of collagen. Label-free SHG microscopy provides a new alternative method for quantifying collagen deposition in fibrotic hearts. PMID:23921804

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

    International Nuclear Information System (INIS)

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

  18. A mobile phone-based care model for outpatient cardiac rehabilitation: the care assessment platform (CAP

    Directory of Open Access Journals (Sweden)

    Francis Rebecca

    2010-01-01

    Full Text Available Abstract Background Cardiac rehabilitation programs offer effective means to prevent recurrence of a cardiac event, but poor uptake of current programs have been reported globally. Home based models are considered as a feasible alternative to avoid various barriers related to care centre based programs. This paper sets out the study design for a clinical trial seeking to test the hypothesis that these programs can be better and more efficiently supported with novel Information and Communication Technologies (ICT. Methods/Design We have integrated mobile phones and web services into a comprehensive home- based care model for outpatient cardiac rehabilitation. Mobile phones with a built-in accelerometer sensor are used to measure physical exercise and WellnessDiary software is used to collect information on patients' physiological risk factors and other health information. Video and teleconferencing are used for mentoring sessions aiming at behavioural modifications through goal setting. The mentors use web-portal to facilitate personal goal setting and to assess the progress of each patient in the program. Educational multimedia content are stored or transferred via messaging systems to the patients phone to be viewed on demand. We have designed a randomised controlled trial to compare the health outcomes and cost efficiency of the proposed model with a traditional community based rehabilitation program. The main outcome measure is adherence to physical exercise guidelines. Discussion The study will provide evidence on using mobile phones and web services for mentoring and self management in a home-based care model targeting sustainable behavioural modifications in cardiac rehabilitation patients. Trial registration The trial has been registered in the Australian New Zealand Clinical Trials Registry (ANZCTR with number ACTRN12609000251224.

  19. Contrast-enhanced cardiac MRI before coronary artery bypass surgery: impact of myocardial scar extent on bypass flow

    International Nuclear Information System (INIS)

    The aim of the study was to relate the extent of myocardial late gadolinium enhancement (LGE) in cardiac MRI to intraoperative graft flow in patients undergoing coronary artery bypass graft (CABG) surgery. Thirty-three CAD patients underwent LGE MRI before surgery using an inversion-recovery GRE sequence (turboFLASH). Intraoperative graft flow in Doppler ultrasonography was compared with the scar extent in each coronary vessel territory. One hundred and fourteen grafts were established supplying 86 of the 99 vessel territories. A significant negative correlation was found between scar extent and graft flow (r = -0.4, p -1; p < 0.0001). In summary, the extent of myocardial scar as defined by contrast-enhanced MRI predicts coronary bypass graft flow. Beyond the probability of functional recovery, preoperative MRI might add value to surgery planning by predicting midterm bypass graft patency. (orig.)

  20. Using high resolution cardiac CT data to model and visualize patient-specific interactions between trabeculae and blood flow.

    Science.gov (United States)

    Kulp, Scott; Gao, Mingchen; Zhang, Shaoting; Qian, Zhen; Voros, Szilard; Metaxas, Dimitris; Axel, Leon

    2011-01-01

    In this paper, we present a method to simulate and visualize blood flow through the human heart, using the reconstructed 4D motion of the endocardial surface of the left ventricle as boundary conditions. The reconstruction captures the motion of the full 3D surfaces of the complex features, such as the papillary muscles and the ventricular trabeculae. We use visualizations of the flow field to view the interactions between the blood and the trabeculae in far more detail than has been achieved previously, which promises to give a better understanding of cardiac flow. Finally, we use our simulation results to compare the blood flow within one healthy heart and two diseased hearts. PMID:22003651

  1. Comparison of simultaneous and sequential SPECT imaging for discrimination tasks in assessment of cardiac defects

    OpenAIRE

    Trott, CM; Ouyang, J.; El Fakhri, G

    2010-01-01

    Simultaneous rest perfusion/fatty-acid metabolism studies have the potential to replace sequential rest/stress perfusion studies for the assessment of cardiac function. Simultaneous acquisition has the benefits of increased signal and lack of need for patient stress, but is complicated by cross-talk between the two radionuclide signals. We consider a simultaneous rest 99mTc-sestamibi/123I-BMIPP imaging protocol in place of the commonly-used sequential rest/stress 99mTc-sestamibi protocol. The...

  2. Use of a Three Dimensional Printed Cardiac Model to Assess Suitability for Biventricular Repair.

    Science.gov (United States)

    Farooqi, Kanwal M; Gonzalez-Lengua, Carlos; Shenoy, Rajesh; Sanz, Javier; Nguyen, Khanh

    2016-05-01

    Three dimensional (3D) printing is rapidly gaining interest in the medical field for use in presurgical planning. We present the case of a seven-year-old boy with double outlet right ventricle who underwent a bidirectional Glenn anastomosis. We used a 3D cardiac model to assess his suitability for a biventricular repair. He underwent a left ventricle-to-aorta baffle with a right ventricle-to-pulmonary artery conduit placement. He did well postoperatively and was discharged home with no evidence of baffle obstruction and good biventricular function. A 3D printed model can provide invaluable intracardiac spatial information in these complex patients. PMID:27009890

  3. Triple Rule Out CTA for Assessing Cardiac, Pulmonary and Aortic Vasculature

    Directory of Open Access Journals (Sweden)

    M. Tehrai

    2007-05-01

    Full Text Available It is now possible with advanced scanners to evaluate patients with chest pain of many causes by using a single computed tomographic angiography (CTA examination to assess them for pulmonary, aortic and cardiac disease. Because of its availability, non-invasiveness, ease of use, and high negative predictive value, CTA may be used as a powerful triple rule out test to evaluate most of life threatening causes of chest pain. I will review the role of CTA in the diag-nosis of these disorders and where this technique stands in comparison with the more conventional methods such as ventilation/perfusion scintigraphy and conventional angiography.

  4. Triple Rule Out CTA for Assessing Cardiac, Pulmonary and Aortic Vasculature

    OpenAIRE

    M. Tehrai

    2007-01-01

    It is now possible with advanced scanners to evaluate patients with chest pain of many causes by using a single computed tomographic angiography (CTA) examination to assess them for pulmonary, aortic and cardiac disease. Because of its availability, non-invasiveness, ease of use, and high negative predictive value, CTA may be used as a powerful triple rule out test to evaluate most of life threatening causes of chest pain. I will review the role of CTA in the diag-nosis of these disorders and...

  5. Assessment of the intrapulmonary ventilation-perfusion distribution after the Fontan procedure for complex cardiac anomalies: Relation to pulmonary hemodynamics

    International Nuclear Information System (INIS)

    In 12 patients who underwent the Fontan procedure for complex cardiac anomalies, lung scanning with xenon-133 was performed to assess the intrapulmonary ventilation-perfusion distribution, and comparison was made with a control group. All data were then analyzed in relation to either pre- or postoperative pulmonary hemodynamic data. In ventilation scans, the intrapulmonary distribution in the right lung was almost normal. In perfusion scans, an abnormal increased upper to lower lobe perfusion ratio greater than the normal value found in the control group was noted in seven patients (58.3%). There was a significant correlation (p less than 0.02) between the upper to lower lobe perfusion ratio and postoperative pulmonary vascular resistance. Furthermore, this perfusion ratio correlated inversely with the preoperative (p less than 0.005) and postoperative (p less than 0.02) right pulmonary artery area index, defined as the ratio of cross-sectional area to the normal value. Of five patients with less than 90% arterial oxygen saturation, four showed an abnormal distribution of pulmonary blood flow greater than the normal perfusion ratio. No patient had evidence of a pulmonary arteriovenous fistula by the echocardiographic contrast study. These results suggest that abnormal distribution of pulmonary blood flow to the upper lung segment may develop in patients after the Fontan procedure, and that insufficient size of the pulmonary artery before operation and the consequent postoperative elevation of pulmonary vascular resistance may be responsible for this perfusion abnormality

  6. Computational Modeling of Open-Irrigated Electrodes for Radiofrequency Cardiac Ablation Including Blood Motion-Saline Flow Interaction

    Science.gov (United States)

    González-Suárez, Ana; Berjano, Enrique; Guerra, Jose M.; Gerardo-Giorda, Luca

    2016-01-01

    Radiofrequency catheter ablation (RFCA) is a routine treatment for cardiac arrhythmias. During RFCA, the electrode-tissue interface temperature should be kept below 80°C to avoid thrombus formation. Open-irrigated electrodes facilitate power delivery while keeping low temperatures around the catheter. No computational model of an open-irrigated electrode in endocardial RFCA accounting for both the saline irrigation flow and the blood motion in the cardiac chamber has been proposed yet. We present the first computational model including both effects at once. The model has been validated against existing experimental results. Computational results showed that the surface lesion width and blood temperature are affected by both the electrode design and the irrigation flow rate. Smaller surface lesion widths and blood temperatures are obtained with higher irrigation flow rate, while the lesion depth is not affected by changing the irrigation flow rate. Larger lesions are obtained with increasing power and the electrode-tissue contact. Also, larger lesions are obtained when electrode is placed horizontally. Overall, the computational findings are in close agreement with previous experimental results providing an excellent tool for future catheter research. PMID:26938638

  7. Assessment of cardiac single-photon emission computed tomography performance using a scanning linear observer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chih-Jie; Kupinski, Matthew A.; Volokh, Lana [College of Optical Sciences, University of Arizona, Tucson, Arizona 85721 (United States); GE Healthcare, Haifa 39120 (Israel)

    2013-01-15

    Purpose: Single-photon emission computed tomography (SPECT) is widely used to detect myocardial ischemia and myocardial infarction. It is important to assess and compare different SPECT system designs in order to achieve the highest detectability of cardiac defects. Methods: Whitaker et al.'s study ['Estimating random signal parameters from noisy images with nuisance parameters: linear and scanning-linear methods,' Opt. Express 16(11), 8150-8173 (2008)] on the scanning linear observer (SLO) shows that the SLO can be used to estimate the location and size of signals. One major advantage of the SLO is that it can be used with projection data rather than with reconstruction data. Thus, this observer model assesses the overall hardware performance independent of any reconstruction algorithm. In addition, the computation time of image quality studies is significantly reduced. In this study, three systems based on the design of the GE cadmium zinc telluride-based dedicated cardiac SPECT camera Discovery 530c were assessed. This design, which is officially named the Alcyone Technology: Discovery NM 530c, was commercialized in August, 2009. The three systems, GE27, GE19, and GE13, contain 27, 19, and 13 detectors, respectively. Clinically, a human heart can be virtually segmented into three coronary artery territories: the left-anterior descending artery, left-circumflex artery, and right coronary artery. One of the most important functions of a cardiac SPECT system is to produce images from which a radiologist can accurately predict in which territory the defect exists [http://www.asnc.org/media/PDFs/PPReporting081511.pdf, Guideline from American Society of Nuclear Cardiology]. A good estimation of the extent of the defect from the projection images is also very helpful for determining the seriousness of the myocardial ischemia. In this study, both the location and extent of defects were estimated by the SLO, and the system performance was assessed by

  8. Sublingual Microcirculation is Impaired in Post-cardiac Arrest Patients

    DEFF Research Database (Denmark)

    G. Omar, Yasser; Massey, Michael; Wiuff Andersen, Lars; A. Giberson, Tyler; Berg, Katherine; N. Cocchi, Michael; I. Shapiro, Nathan; W. Donnino, Michael

    2013-01-01

    markers in the post-cardiac arrest state. METHODS: We prospectively evaluated the sublingual microcirculation in post-cardiac arrest patients, severe sepsis/septic shock patients, and healthy control patients using Sidestream Darkfield microscopy. Microcirculatory flow was assessed using the...... microcirculation flow index (MFI) at 6 and 24h in the cardiac arrest patients, and within 6h of emergency department admission in the sepsis and control patients. RESULTS: We evaluated 30 post-cardiac arrest patients, 16 severe sepsis/septic shock patients, and 9 healthy control patients. Sublingual...... microcirculatory blood flow was significantly impaired in post-cardiac arrest patients at 6h (MFI 2.6 [IQR: 2-2.9]) and 24h (2.7 [IQR: 2.3-2.9]) compared to controls (3.0 [IQR: 2.9-3.0]; p<0.01 and 0.02, respectively). After adjustment for initial APACHE II score, post-cardiac arrest patients had significantly...

  9. Epidemiological and clinical use of GMHAT-PC (Global Mental Health assessment tool – primary care in cardiac patients

    Directory of Open Access Journals (Sweden)

    Krishna Murali

    2009-04-01

    Full Text Available Abstract Background A computer assisted interview, the GMHAT/PC has been developed to assist General Practitioners and other Health Professionals to make a quick, convenient and comprehensive standardised mental health assessment. It has proved to be a reliable and valid tool in our previous studies involving General Practitioners and Nurses. Little is known about its use in cardiac rehabilitation settings. Aim The study aims to assess the feasibility of using a computer assisted diagnostic interview by nurses for patients attending Cardiac Rehabilitation Clinics and to examine the level of agreement between the GMHAT/PC diagnosis and a Psychiatrist clinical diagnosis. Prevalence of mental illness was also measured. Design Cross sectional validation and feasibility study. Methods Nurses using GMHAT/PC examined consecutive patients presenting to a cardiac rehabilitation centre. A total of 118 patients were assessed by nurses and consultant psychiatrist in cardiac rehabilitation centres. The kappa coefficient (κ, sensitivity, and specificity of the GMHAT/PC diagnosis were analysed as measures of validity. The time taken for the interview as well as feedback from patients and interviewers were indicators of feasibility. Data on prevalence of mental disorders in an outpatient cardiac rehabilitation setting was collected. Results The mean duration of the interview was 14 minutes. Feedback from patients and interviewers indicated good practical feasibility. The agreement between GMHAT/PC interview-based diagnoses and consultant psychiatrists' ICD-10 criteria-based clinical diagnosis was good or excellent (κ = 0.76, sensitivity = 0.73, specificity = 0.90. The prevalence of mental disorders in this group was 22%, predominantly depression. Very few cases were on treatment. Conclusion GMHAT/PC can assist nurses in making accurate mental health assessments and diagnoses in a cardiac rehabilitation setting and is acceptable to cardiac patients. It can

  10. Flowtran assessment for predicting flow instability

    International Nuclear Information System (INIS)

    FLOWTRAN is a thermal-hydraulic assembly code for simulating Savannah River Site (SRS) reactor assemblies and predicting flow instability. Reactor power and flow transient modelling is critical in determining safe operating limits at which a reactor could be shut down without damage to the fuel assemblies. FLOWTRAN models an individual assembly's thermal-hydraulic behavior and can determine the operating power limit to avoid flow instability when the flow regime through the assembly is single-phase. Tests were conducted at Columbia University in 1988--89 with downward flow through single tubes to examine fluid flow instability. FLOWTRAN cannot predict actual flow instability because it cannot model two-phase flow. FLOWTRAN modelled the heated tubes to predict Onset of Significant Voiding (OSV) using the Saha-Zuber's correlation modified for SRS reactors; data analyses for the Columbia tests showed that the modified correlation OSV is a conservative predictor for downward flow instability

  11. Prospective coronary angioscopy assessment of allograft coronary artery disease in human cardiac transplant recipients

    Science.gov (United States)

    Jain, Ashit; Ventura, Hector O.; Collins, Tyrone J.; Ramee, Stephen R.; White, Christopher J.

    1993-09-01

    Annual angiographic assessment to determine the presence or progression of allograft coronary artery disease (CAD) has been unable to modify the natural history of this disease. Coronary angioscopy is a sensitive method to detect the early presence of coronary artery disease and in a retrospective analysis severity of CAD by angioscopy correlated with the time since transplantation. The purpose of this study was to prospectively evaluate progression of coronary artery disease over a one year period in 40 cardiac transplant recipients. The progression of coronary artery disease as assessed by angioscopy is directly related to time after transplantation and therefore angioscopy may be the method of choice for detection and evaluation of therapeutic regimens to control allograft coronary artery disease.

  12. Assessment of cardiac function by radionuclide angiocardiography in children with cardiomyopathy

    International Nuclear Information System (INIS)

    Radionuclide angiography was performed in four children, each having dilated cardiomyopathy (DCM), hypertrophic nonobstructive cardiomyopathy (HCM), hypertrophic obstructive cardiomyopathy (HOCM), or restrictive cardiomyopathy (RCM), whose ages ranged from 5 to 8 years. The peak to peak time of flow from the right to left ventricle, which was corrected by heart rate, was prolonged in all the patients. Left ventricular ejection fraction was low in the DCM patient, and high in the HOCM patient. In the DCM patient, both peak ejection rate and peak filling rate of the left ventricle were low. Two patients with either DCM or HOCM had the prolongation of percent duration to peak filling rate, as opposed to the RCM patient having short percent duration. In the RCM patient, right ventricular ejection fraction was low, and time-volume curve showed rapid filling during early diastole. Radionuclide angiography is recommended as a noninvasive method of evaluating cardiac functional characteristics for various types of myocardiopathy. (Namekawa, K.)

  13. Cardiac remodeling following percutaneous mitral valve repair. Initial results assessed by cardiovascular magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Radunski, U.K [University Heart Center, Hamburg (Germany). Cardiology; Franzen, O. [Rigshospitalet, Copenhagen (Denmark). Cardiology; Barmeyer, A. [Klinikum Dortmund (Germany). Kardiologie; and others

    2014-10-15

    Percutaneous mitral valve repair with the MitraClip device (Abbott Vascular, Redwood City, California, USA) is a novel therapeutic option in patients with mitral regurgitation. This study evaluated the feasibility of cardiac volume measurements by cardiovascular magnetic resonance imaging (CMR) to assess reverse myocardial remodeling in patients after MitraClip implantation. 12 patients underwent CMR at baseline (BL) before and at 6 months follow-up (FU) after MitraClip implantation. Cine-CMR was performed in short- and long-axes for the assessment of left ventricular (LV), right ventricular (RV) and left atrial (LA) volumes. Assessment of endocardial contours was not compromised by the device-related artifact. No significant differences in observer variances were observed for LV, RV and LA volume measurements between BL and FU. LV end-diastolic (median 127 [IQR 96-150] vs. 112 [86-150] ml/m{sup 2}; p=0.03) and LV end-systolic (82 [54-91] vs. 69 [48-99] ml/m{sup 2}; p=0.03) volume indices decreased significantly from BL to FU. No significant differences were found for RV end-diastolic (94 [75-103] vs. 99 [77-123] ml/m{sup 2}; p=0.91), RV end-systolic (48 [42-80] vs. 51 [40-81] ml/m{sup 2}; p=0.48), and LA (87 [55-124] vs. 92 [48-137]R ml/m{sup 2}; p=0.20) volume indices between BL and FU. CMR enables the assessment of cardiac volumes in patients after MitraClip implantation. Our CMR findings indicate that percutaneous mitral valve repair results in reverse LV but not in RV or LA remodeling.

  14. TU-A-12A-09: Absolute Blood Flow Measurement in a Cardiac Phantom Using Low Dose CT

    Energy Technology Data Exchange (ETDEWEB)

    Ziemer, B; Hubbard, L; Lipinski, J; Molloi, S [University of California, Irvine, CA (United States)

    2014-06-15

    Purpose: To investigate a first pass analysis technique to measure absolute flow from low dose CT images in a cardiac phantom. This technique can be combined with a myocardial mass assignment to yield absolute perfusion using only two volume scans and reduce the radiation dose to the patient. Methods: A four-chamber cardiac phantom and perfusion chamber were constructed from poly-acrylic and connected with tubing to approximate anatomical features. The system was connected to a pulsatile pump, input/output reservoirs and power contrast injector. Flow was varied in the range of 1-2.67 mL/s with the pump operating at 60 beats/min. The system was imaged once a second for 14 seconds with a 320-row scanner (Toshiba Medical Systems) using a contrast-enhanced, prospective-gated cardiac perfusion protocol. Flow was calculated by the following steps: subsequent images of the perfusion volume were subtracted to find the contrast entering the volume; this was normalized by an upstream, known volume region to convert Hounsfield (HU) values to concentration; this was divided by the subtracted images time difference. The technique requires a relatively stable input contrast concentration and no contrast can leave the perfusion volume before the flow measurement is completed. Results: The flow calculated from the images showed an excellent correlation with the known rates. The data was fit to a linear function with slope 1.03, intercept 0.02 and an R{sup 2} value of 0.99. The average root mean square (RMS) error was 0.15 mL/s and the average standard deviation was 0.14 mL/s. The flow rate was stable within 7.7% across the full scan and served to validate model assumptions. Conclusion: Accurate, absolute flow rates were measured from CT images using a conservation of mass model. Measurements can be made using two volume scans which can substantially reduce the radiation dose compared with current dynamic perfusion techniques.

  15. TU-A-12A-09: Absolute Blood Flow Measurement in a Cardiac Phantom Using Low Dose CT

    International Nuclear Information System (INIS)

    Purpose: To investigate a first pass analysis technique to measure absolute flow from low dose CT images in a cardiac phantom. This technique can be combined with a myocardial mass assignment to yield absolute perfusion using only two volume scans and reduce the radiation dose to the patient. Methods: A four-chamber cardiac phantom and perfusion chamber were constructed from poly-acrylic and connected with tubing to approximate anatomical features. The system was connected to a pulsatile pump, input/output reservoirs and power contrast injector. Flow was varied in the range of 1-2.67 mL/s with the pump operating at 60 beats/min. The system was imaged once a second for 14 seconds with a 320-row scanner (Toshiba Medical Systems) using a contrast-enhanced, prospective-gated cardiac perfusion protocol. Flow was calculated by the following steps: subsequent images of the perfusion volume were subtracted to find the contrast entering the volume; this was normalized by an upstream, known volume region to convert Hounsfield (HU) values to concentration; this was divided by the subtracted images time difference. The technique requires a relatively stable input contrast concentration and no contrast can leave the perfusion volume before the flow measurement is completed. Results: The flow calculated from the images showed an excellent correlation with the known rates. The data was fit to a linear function with slope 1.03, intercept 0.02 and an R2 value of 0.99. The average root mean square (RMS) error was 0.15 mL/s and the average standard deviation was 0.14 mL/s. The flow rate was stable within 7.7% across the full scan and served to validate model assumptions. Conclusion: Accurate, absolute flow rates were measured from CT images using a conservation of mass model. Measurements can be made using two volume scans which can substantially reduce the radiation dose compared with current dynamic perfusion techniques

  16. Assessment of atherosclerotic plaque vulnerability of coronary arteries in cases of sudden cardiac death

    International Nuclear Information System (INIS)

    To study the plaque vulnerability in coronary arteries taken from autopsy specimens, of individuals dying of ischemic heart disease in our setup and to compare it with atheroma of those who died of non-cardiac causes. Sixty coronary arteries having atherosclerosis, from autopsies of patients who died of sudden cardiac death were divided into case and control groups. Case group included thirty coronary arteries having atherosclerosis from autopsies of patients of whose death was attributable to Ischemic Heart Disease (IHD). Control group included thirty coronary arteries where atherosclerotic changes were found by chance (death not attributable to ischemic heart disease). Plaques were assessed for fibrous cap thickness, foam cells; mean percentage of inflammatory cells on Haemotoxylin and Eosin (H and E) stained slides whereas immunohistochemical (IHC) markers for T-Cells were done by IHC stain method. In present study, foam cells are significantly more in study group than in control group (P=0.007). Fibrous cap thickness fulfilling the criteria of vulnerable plaque was more in study group as compared to control group (P<0.001). The present study demonstrated that there was insignificant difference (P=0.152), in the mean percentage of inflammatory cells in case group and control group. An overall significant association was found between vulnerable plaque and death due to ischemic heart disease (P<0.001). Conclusion: Patients dying of ischemic heart disease have more vulnerable plaque in their coronary arteries as compared to those dying from non ischemic cause. Although this is an autopsy study but the significance of in this study can be very important to guide cardiologists to identify patients at high risk of acute coronary syndrome and use new diagnostic modalities like intravascular ultrasonography and therapeutic strategies like genomic and proteomic techniques. This will help the early detection and treatment of such cases and may ultimately reduce the

  17. Technical assessment of whole body angiography and cardiac function within a single MRI examination

    International Nuclear Information System (INIS)

    Aim: To evaluate a combined protocol for simultaneous cardiac MRI (CMR) and contrast-enhanced (CE) whole-body MR angiography (WB-MRA) techniques within a single examination. Materials and methods: Asymptomatic volunteers (n = 48) with low-moderate risk of cardiovascular disease (CVD) were recruited. The protocol was divided into four sections: (1) CMR of left ventricle (LV) structure and function; (2) CE-MRA of the head, neck, and thorax followed by the distal lower limbs; (3) CMR LV “late gadolinium enhancement” assessment; and (4) CE-MRA of the abdomen and pelvis followed by the proximal lower limbs. Multiple observers undertook the image analysis. Results: For CMR, the mean ejection fraction (EF) was 67.3 ± 4.8% and mean left ventricular mass (LVM) was 100.3 ± 22.8 g. The intra-observer repeatability for EF ranged from 2.1–4.7% and from 9–12 g for LVM. Interobserver repeatability was 8.1% for EF and 19.1 g for LVM. No LV delayed myocardial enhancement was observed. For WB-MRA, some degree of luminal narrowing or stenosis was seen at 3.6% of the vessel segments (involving n = 29 of 48 volunteers) and interobserver radiological opinion was consistent in 96.7% of 1488 vessel segments assessed. Conclusion: Combined assessment of WB-MRA and CMR can be undertaken within a single examination on a clinical MRI system. The associated analysis techniques are repeatable and may be suitable for larger-scale cardiovascular MRI studies. - Highlights: • We report the use of whole body MR angiography and cardiac MR as a single examination. • Healthy volunteers with elevated cardiovascular disease risk were scanned. • Vessel segments and cardiac function were assessed by Radiologists and Physicists respectively. • The protocol took an average of 51 minutes to complete, and analyses were repeatable. • This combined cardiovascular MRI protocol will be used for better targeting of future interventions

  18. Exercise-related change in airway blood flow in humans: Relationship to changes in cardiac output and ventilation

    OpenAIRE

    Morris, Norman R; Ceridon, Maile L.; Beck, Kenneth C.; Strom, Nicholas A.; Schneider, Donald A; Mendes, Eliana S; Wanner, Adam; Johnson, Bruce D.

    2008-01-01

    This study examined the relationship between airway blood flow (Q̇aw), ventilation (V̇E) and cardiac output (Q̇tot) during exercise in healthy humans (n = 12, mean age 34 ± 11 yr). Q̇aw was estimated from the uptake of the soluble gas dimethyl ether while V̇E and Q̇tot were measured using open circuit spirometry. Measurements were made prior to and during exercise at 34 ± 5W (Load 1) and 68 ± 10 W (Load 2) and following the cessation of exercise (recovery). Q̇aw increased in a stepwise fashio...

  19. Design and implementation of an equipment intended for continuous follow up of cardiac flow from the gamma-cardiogram

    International Nuclear Information System (INIS)

    This paper provides a methodology to follow up continuously the cardiac flow from gamma-cardiogram's recordings. From a good signal to noise ratio in the Fourier series first term we compute the signal amplitude. The practical interest of the methodology was confirmed by results from patients with arterio veinous fistula. From a fundamental phasis study we derived its dispersion to be an important factor for the signal reliability (reproducibility, arythmy, etc..). A measure scale has been achieved. A conversational display terminal is now connected on-line with a MITRA 15 and in a near future we are planning to work on a microprocessor

  20. Assessing cardiac preload by the Initial Systolic Time Interval obtained from impedance cardiography

    Directory of Open Access Journals (Sweden)

    Jan H Meijer

    2010-01-01

    Full Text Available The Initial Systolic Time Interval (ISTI, obtained from the electrocardiogram (ECG and impedance cardiogram (ICG, is considered to be a measure for the time delay between the electrical and mechanical activity of the heart and reflects an early active period of the cardiac cycle. The clinical relevance of this time interval is subject of study. This paper presents preliminary results of a pilot study investigating the use of ISTI in evaluating and predicting the circulatory response to fluid administration in patients after coronary artery bypass graft surgery, by comparing ISTI with cardiac output (CO responsiveness. Also the use of the pulse transit time (PTT, earlier recommended for this purpose, is investigated. The results show an inverse relationship between ISTI and CO at all moments of fluid administration and also an inverse relationship between the changes ΔISTI and ΔCO before and after full fluid administration. No relationships between PTT and CO or ΔPTT and ΔCO were found. It is concluded that ISTI is dependent upon preload, and that ISTI has the potential to be used as a clinical parameter assessing preload.

  1. Cardiac remodeling following percutaneous mitral valve repair - initial results assessed by cardiovascular magnetic resonance imaging

    DEFF Research Database (Denmark)

    Radunski, U K; Franzen, O; Barmeyer, A;

    2014-01-01

    PURPOSE: Percutaneous mitral valve repair with the MitraClip device (Abbott Vascular, Redwood City, California, USA) is a novel therapeutic option in patients with mitral regurgitation. This study evaluated the feasibility of cardiac volume measurements by cardiovascular magnetic resonance imaging...... mitral valve repair results in reverse LV but not in RV or LA remodeling. KEY POINTS: • Volume measurements by cardiovascular magnetic resonance imaging are feasible following percutaneous mitral valve repair despite device-related artifacts.• A significant reduction of left ventricular volume was found...... end-systolic (48 [42 - 80] vs. 51 [40 - 81] ml/m(2); p = 0.48), and LA (87 [55 - 124] vs. 92 [48 - 137] ml/m(2); p = 0.20) volume indices between BL and FU. CONCLUSION: CMR enables the assessment of cardiac volumes in patients after MitraClip implantation. Our CMR findings indicate that percutaneous...

  2. Assessment of inflammatory factors and cardiac troponin T in hemodialysis patients

    International Nuclear Information System (INIS)

    Hemodialysis (Hd) patients suffer from chronic inflammations which make them at increased risk of cardiovascular diseases. The purpose of this study was to see if there is a significant association between inflammatory factors such as ferritin and C-reactive protein (CRP) as well as troponin T in patients on HD. We assessed these serum factors as well as other known cardiac risk factors in 53 patients on HD. The serum ferritin and CRP levels were measured by chemiluminescences immune assay while troponin T levels were measured by electrochemist luminescence immune assay. We found that serum concentrations of CRP and ferritin were not significantly higher in patients on HD with known cardiac risk factors (compared with the control group) (p< 0.05). However, the serum troponin T levels in HD patients with cardiovascular risk factors were significantly higher than the control group. Our study suggests that elevated serum troponin T levels can play an important role as a predictor of cardiovascular disease in HD patients. Also, inflammatory factors such as CRP and ferritin may be influenced by chronic inflammation or nutritional status of these patients. (author)

  3. Impact of extracorporeal blood flow rate on blood pressure, pulse rate and cardiac output during haemodialysis

    DEFF Research Database (Denmark)

    Schytz, Philip Andreas; Mace, Maria Lerche; Soja, Anne Merete Boas;

    2015-01-01

    reducing EBFR on BP exists and data are conflicting. The aim of this study was to evaluate the effect and the potential mechanism(s) involved by investigating the impact of changes in EBFR on BP, pulse rate (PR) and cardiac output (CO) in HD patients with arteriovenous-fistulas (AV-fistulas). METHODS: We...

  4. Debris flow hazards mitigation--Mechanics, prediction, and assessment

    Science.gov (United States)

    2007-01-01

    These proceedings contain papers presented at the Fourth International Conference on Debris-Flow Hazards Mitigation: Mechanics, Prediction, and Assessment held in Chengdu, China, September 10-13, 2007. The papers cover a wide range of topics on debris-flow science and engineering, including the factors triggering debris flows, geomorphic effects, mechanics of debris flows (e.g., rheology, fluvial mechanisms, erosion and deposition processes), numerical modeling, various debris-flow experiments, landslide-induced debris flows, assessment of debris-flow hazards and risk, field observations and measurements, monitoring and alert systems, structural and non-structural countermeasures against debris-flow hazards and case studies. The papers reflect the latest devel-opments and advances in debris-flow research. Several studies discuss the development and appli-cation of Geographic Information System (GIS) and Remote Sensing (RS) technologies in debris-flow hazard/risk assessment. Timely topics presented in a few papers also include the development of new or innovative techniques for debris-flow monitoring and alert systems, especially an infra-sound acoustic sensor for detecting debris flows. Many case studies illustrate a wide variety of debris-flow hazards and related phenomena as well as their hazardous effects on human activities and settlements.

  5. Cardiac CT for the assessment of chest pain: Imaging techniques and clinical results

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Hans-Christoph, E-mail: christoph.becker@med.uni-muenchen.de [Ludwig-Maximilians-University, Grosshadern Clinic, Department of Clinical Radiology, Marchioninistr. 15, 81377 Munich (Germany); Johnson, Thorsten [Ludwig-Maximilians-University, Grosshadern Clinic, Department of Clinical Radiology, Marchioninistr. 15, 81377 Munich (Germany)

    2012-12-15

    Immediate and efficient risk stratification and management of patients with acute chest pain in the emergency department is challenging. Traditional management of these patients includes serial ECG, laboratory tests and further on radionuclide perfusion imaging or ECG treadmill testing. Due to the advances of multi-detector CT technology, dedicated coronary CT angiography provides the potential to rapidly and reliably diagnose or exclude acute coronary artery disease. Life-threatening causes of chest pain, such as aortic dissection and pulmonary embolism can simultaneously be assessed with a single scan, sometimes referred to as “triple rule out” scan. With appropriate patient selection, cardiac CT can accurately diagnose heart disease or other sources of chest pain, markedly decrease health care costs, and reliably predict clinical outcomes. This article reviews imaging techniques and clinical results for CT been used to evaluate patients with chest pain entering the emergency department.

  6. Cardiac CT for the assessment of chest pain: Imaging techniques and clinical results

    International Nuclear Information System (INIS)

    Immediate and efficient risk stratification and management of patients with acute chest pain in the emergency department is challenging. Traditional management of these patients includes serial ECG, laboratory tests and further on radionuclide perfusion imaging or ECG treadmill testing. Due to the advances of multi-detector CT technology, dedicated coronary CT angiography provides the potential to rapidly and reliably diagnose or exclude acute coronary artery disease. Life-threatening causes of chest pain, such as aortic dissection and pulmonary embolism can simultaneously be assessed with a single scan, sometimes referred to as “triple rule out” scan. With appropriate patient selection, cardiac CT can accurately diagnose heart disease or other sources of chest pain, markedly decrease health care costs, and reliably predict clinical outcomes. This article reviews imaging techniques and clinical results for CT been used to evaluate patients with chest pain entering the emergency department.

  7. Assessing future changes in pan-European environmental flows

    OpenAIRE

    Laize, Cedric L.R.; Acreman, M.; Dunbar, M.; Houghton-Carr, H.; Florke, M.; Schneider, C; Hannah, D. M.

    2011-01-01

    The potential river flow-driven impact of change on aquatic and riparian ecosystems at the pan-European scale under various climatological and development scenarios was assessed using a methodology based conceptually on the Range of Variability Approach (RVA) using the Indicators of Hydrological Alteration (IHA): a desk-top technique for assessing if environmental flow requirements. This paper presents an adaptation of the IHA approach using monthly flows. European and Mediterranean river net...

  8. Cardiac perception and cardiac control. A review.

    Science.gov (United States)

    Carroll, D

    1977-12-01

    The evidence regarding specific cardiac perception and discrimination, and its relationship to voluntary cardiac control, is critically reviewed. Studies are considered in three sections, depending on the method used to assess cardiac perception: questionnaire assessment, discrimination procedures, and heartbeat tracking. The heartbeat tracking procedure would appear to suffer least from interpretative difficulties. Recommendations are made regarding the style of analysis used to assess heartbeat perception in such tracking tasks. PMID:348240

  9. Quantitative assessment of mitral and aortic insufficiency from effective systemic ejection fraction measured by radiocardiography and cardiac chambers scanning

    International Nuclear Information System (INIS)

    Comparison between the effective systemic ejection fraction defined by radiocardiography and cardiac chambers scanning, and the whole left ventricular ejection fraction calculated by cineangiocardiography allows an accurate assessment of mitral and aortic regurgitation extent. In case of both mitral and aortic insufficiency, each regurgitation can be quantitatively dissociated by means of the aortic isotopic dilution curve recorded at the same time as the radiocardiogram

  10. Can Stress Echocardiography Compete with Perfusion Scintigraphy in the Detection of Coronary Artery Disease and Cardiac Risk Assessment?

    NARCIS (Netherlands)

    M.L. Geleijnse (Marcel); A. Elhendy (Abdou)

    2000-01-01

    textabstractAims: The aim of this review was to define the place of stress echocardiography in the context of perfusion scintigraphy for the detection of coronary artery disease (CAD) and the assessment of cardiac risk. Stress echocardiography has the benefits of widespread availability, relatively

  11. Simultaneous evaluation of myocardial blood flow, cardiac function and lung water content using [15O]H2O and positron emission tomography

    International Nuclear Information System (INIS)

    This study sought to evaluate an imaging approach using [15O]H2O and positron emission tomography (PET) for simultaneous assessment of myocardial perfusion, cardiac function and lung water content as a potential indicator of pulmonary oedema. Twenty-six subjects divided into two groups (group I, 13 patients with idiopathic dilated cardiomyopathy; group II, 13 healthy volunteers) underwent dynamic PET scanning after intravenous infusion of ∼995 MBq [15O]H2O. In both groups, echocardiograms were performed after the PET studies. From the dynamic [15O]H2O data, lung water content (LWC) at equilibrium, myocardial blood flow (MBF), cardiac output (CO), stroke volume (SV) and stroke volume indexes (SVI) using the indicator dilution principle were determined. LWC was 18% (p = 0.038) higher in patients than in controls. Global MBF did not differ significantly between the groups, but regional MBF values were significantly lower (p 0.1) of -0.02 ± 0.82 vs -0.05 ± 0.54 l/min (CO), -1.44 ± 14.31 vs 1.70 ± 10.56 ml/beat (SV) and 0.47 ± 6.21 vs 0.30 ± 5.02 ml/beat/m2 (SVI). The 95% limits of agreement were -1.62 to 1.59 vs -1.11 to 1.01 l/min (CO), -26.61 to 29.49 vs -22.39 to 18.99 ml/beat (SV) and -11.69 to 12.88 vs -9.53 to 10.14 ml/beat/m2 (SVI). Right ventricular CO was increased by 33% (p = 0.014) in the patient group as compared with normal controls. Our results demonstrate that additional analysis of cardiac function and lung water content are feasible from the dynamic cardiac [15O]H2O PET studies acquired for myocardial perfusion. The parameters appear to work as expected. Further studies are warranted to elucidate the clinical value of these new parameters. (orig.)

  12. Design of a Pulsatile Flow Facility to Evaluate Thrombogenic Potential of Implantable Cardiac Devices

    OpenAIRE

    Arjunon, Sivakkumar; Ardana, Pablo Hidalgo; Saikrishnan, Neelakantan; Madhani, Shalv; Foster, Brent; Glezer, Ari; Yoganathan, Ajit P.

    2015-01-01

    Due to expensive nature of clinical trials, implantable cardiac devices should first be extensively characterized in vitro. Prosthetic heart valves (PHVs), an important class of these devices, have been shown to be associated with thromboembolic complications. Although various in vitro systems have been designed to quantify blood-cell damage and platelet activation caused by nonphysiological hemodynamic shear stresses in these PHVs, very few systems attempt to characterize both blood damage a...

  13. Novel phase-based noise reduction strategy for quantification of left ventricular function and mass assessment by cardiac CT: Comparison with cardiac magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Wai, Bryan, E-mail: bwai@partners.org [Cardiac MR PET CT Program, Division of Cardiology and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts (United States); Thai, Wai-ee [Cardiac MR PET CT Program, Division of Cardiology and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts (United States); Brown, Heather [Qi Imaging, Redwood City, California (United States); Truong, Quynh A. [Cardiac MR PET CT Program, Division of Cardiology and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts (United States)

    2013-08-15

    Background: Tube current modulation in retrospective ECG gated cardiac computed tomography (CT) results in increased image noise and may reduce the accuracy of left ventricular (LV) ejection fraction (EF) and mass assessment. Objective: To examine the effects of a novel CT phase-based noise reduction (NR) algorithm on LV EF and mass quantification as compared to cardiac magnetic resonance (CMR). Methods: In 40 subjects, we compared the LV EF and mass between CT and CMR. In a subset of 24 subjects with tube current modulated CT, the effect of phase-based noise reduction strategies on contrast-to-noise ratio (CNR) and the assessment of LV EF and mass was compared to CMR. Results: There was excellent correlation between CT and CMR for EF (r = 0.94) and mass (r = 0.97). As compared to CMR, the limits of agreement improved with increasing strength of NR strategy. There was a systematic underestimation of LV mass by CT compared to CMR with no NR (−10.3 ± 10.1 g) and low NR (−10.3 ± 12.5 g), but was attenuated with high NR (−0.5 ± 8.3 g). Studies without NR had lower CNR compared to low and high NR at both the ES phase and ED phase (all p < 0.01). Conclusions: A high NR strategy on tube current modulated functional cardiac CT improves correlation of EF compared to CMR and reduces variability of EF and mass evaluation by increasing the CNR. In an effort to reduce radiation dose with tube current modulation, this strategy provides better image quality when LV function and mass quantification is needed.

  14. Novel phase-based noise reduction strategy for quantification of left ventricular function and mass assessment by cardiac CT: Comparison with cardiac magnetic resonance

    International Nuclear Information System (INIS)

    Background: Tube current modulation in retrospective ECG gated cardiac computed tomography (CT) results in increased image noise and may reduce the accuracy of left ventricular (LV) ejection fraction (EF) and mass assessment. Objective: To examine the effects of a novel CT phase-based noise reduction (NR) algorithm on LV EF and mass quantification as compared to cardiac magnetic resonance (CMR). Methods: In 40 subjects, we compared the LV EF and mass between CT and CMR. In a subset of 24 subjects with tube current modulated CT, the effect of phase-based noise reduction strategies on contrast-to-noise ratio (CNR) and the assessment of LV EF and mass was compared to CMR. Results: There was excellent correlation between CT and CMR for EF (r = 0.94) and mass (r = 0.97). As compared to CMR, the limits of agreement improved with increasing strength of NR strategy. There was a systematic underestimation of LV mass by CT compared to CMR with no NR (−10.3 ± 10.1 g) and low NR (−10.3 ± 12.5 g), but was attenuated with high NR (−0.5 ± 8.3 g). Studies without NR had lower CNR compared to low and high NR at both the ES phase and ED phase (all p < 0.01). Conclusions: A high NR strategy on tube current modulated functional cardiac CT improves correlation of EF compared to CMR and reduces variability of EF and mass evaluation by increasing the CNR. In an effort to reduce radiation dose with tube current modulation, this strategy provides better image quality when LV function and mass quantification is needed

  15. Assessment of potential drug-drug interactions and its associated factors in the hospitalized cardiac patients.

    Science.gov (United States)

    Murtaza, Ghulam; Khan, Muhammad Yasir Ghani; Azhar, Saira; Khan, Shujaat Ali; Khan, Tahir M

    2016-03-01

    Drug-drug interactions (DDIs) may result in the alteration of therapeutic response. Sometimes they may increase the untoward effects of many drugs. Hospitalized cardiac patients need more attention regarding drug-drug interactions due to complexity of their disease and therapeutic regimen. This research was performed to find out types, prevalence and association between various predictors of potential drug-drug interactions (pDDIs) in the Department of Cardiology and to report common interactions. This study was performed in the hospitalized cardiac patients at Ayub Teaching Hospital, Abbottabad, Pakistan. Patient charts of 2342 patients were assessed for pDDIs using Micromedex® Drug Information. Logistic regression was applied to find predictors of pDDIs. The main outcome measure in the study was the association of the potential drug-drug interactions with various factors such as age, gender, polypharmacy, and hospital stay of the patients. We identified 53 interacting-combinations that were present in total 5109 pDDIs with median number of 02 pDDIs per patient. Overall, 91.6% patients had at least one pDDI; 86.3% were having at least one major pDDI, and 84.5% patients had at least one moderate pDDI. Among 5109 identified pDDIs, most were of moderate (55%) or major severity (45%); established (24.2%), theoretical (18.8%) or probable (57%) type of scientific evidence. Top 10 common pDDIs included 3 major and 7 moderate interactions. Results obtained by multivariate logistic regression revealed a significant association of the occurrence of pDDIs in patient with age of 60 years or more (p Older patients, patients with longer hospital stay and with elevated number of prescribed drugs were at higher risk of pDDIs. PMID:27013915

  16. A multi-region assessment of population rates of cardiac catheterization and yield of high-risk coronary artery disease

    Directory of Open Access Journals (Sweden)

    Clement Fiona M

    2011-11-01

    Full Text Available Abstract Background There is variation in cardiac catheterization utilization across jurisdictions. Previous work from Alberta, Canada, showed no evidence of a plateau in the yield of high-risk disease at cardiac catheterization rates as high as 600 per 100,000 population suggesting that the optimal rate is higher. This work aims 1 To determine if a previously demonstrated linear relationship between the yield of high-risk coronary disease and cardiac catheterization rates persists with contemporary data and 2 to explore whether the linear relationship exists in other jurisdictions. Methods Detailed clinical information on all patients undergoing cardiac catheterization in 3 Canadian provinces was available through the Alberta Provincial Project for Outcomes Assessment in Coronary Heart (APPROACH disease and partner initiatives in British Columbia and Nova Scotia. Population rates of catheterization and high-risk coronary disease detection for each health region in these three provinces, and age-adjusted rates produced using direct standardization. A mixed effects regression analysis was performed to assess the relationship between catheterization rate and high-risk coronary disease detection. Results In the contemporary Alberta data, we found a linear relationship between the population catheterization rate and the high-risk yield. Although the yield was slightly less in time period 2 (2002-2006 than in time period 1(1995-2001, there was no statistical evidence of a plateau. The linear relationship between catheterization rate and high-risk yield was similarly demonstrated in British Columbia and Nova Scotia and appears to extend, without a plateau in yield, to rates over 800 procedures per 100,000 population. Conclusions Our study demonstrates a consistent finding, over time and across jurisdictions, of linearly increasing detection of high-risk CAD as population rates of cardiac catheterization increase. This internationally-relevant finding

  17. Prehospital randomised assessment of a mechanical compression device in cardiac arrest (PaRAMeDIC trial protocol

    Directory of Open Access Journals (Sweden)

    McCabe Chris

    2010-11-01

    Full Text Available Abstract Background Survival after out-of-hospital cardiac arrest is closely linked to the quality of CPR, but in real life, resuscitation during prehospital care and ambulance transport is often suboptimal. Mechanical chest compression devices deliver consistent chest compressions, are not prone to fatigue and could potentially overcome some of the limitations of manual chest compression. However, there is no high-quality evidence that they improve clinical outcomes, or that they are cost effective. The Prehospital Randomised Assessment of a Mechanical Compression Device In Cardiac Arrest (PARAMEDIC trial is a pragmatic cluster randomised study of the LUCAS-2 device in adult patients with non-traumatic out-of-hospital cardiac arrest. Methods/design The primary objective of this trial is to evaluate the effect of chest compression using LUCAS-2 on mortality at 30 days post out-of-hospital cardiac arrest, compared with manual chest compression. Secondary objectives of the study are to evaluate the effects of LUCAS-2 on survival to 12 months, cognitive and quality of life outcomes and cost-effectiveness. Methods: Ambulance service vehicles will be randomised to either manual compression (control or LUCAS arms. Adult patients in out-of-hospital cardiac arrest, attended by a trial vehicle will be eligible for inclusion. Patients with traumatic cardiac arrest or who are pregnant will be excluded. The trial will recruit approximately 4000 patients from England, Wales and Scotland. A waiver of initial consent has been approved by the Research Ethics Committees. Consent will be sought from survivors for participation in the follow-up phase. Conclusion The trial will assess the clinical and cost effectiveness of the LUCAS-2 mechanical chest compression device. Trial Registration: The trial is registered on the International Standard Randomised Controlled Trial Number Registry (ISRCTN08233942.

  18. Debris Flow Hazard Assessment Based on Support Vector Machine

    Institute of Scientific and Technical Information of China (English)

    YUAN Lifeng; ZHANG Youshui

    2006-01-01

    Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine (SVM) theory, we selected 259 basic data of 37 debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

  19. Regional assessment of LV wall in infarcted heart using tagged MRI and cardiac modelling

    Science.gov (United States)

    Jahanzad, Zeinab; Miin Liew, Yih; Bilgen, Mehmet; McLaughlin, Robert A.; Onn Leong, Chen; Chee, Kok Han; Aziz, Yang Faridah Abdul; Ung, Ngie Min; Lai, Khin Wee; Ng, Siew-Cheok; Lim, Einly

    2015-05-01

    A segmental two-parameter empirical deformable model is proposed for evaluating regional motion abnormality of the left ventricle. Short-axis tagged MRI scans were acquired from 10 healthy subjects and 10 postinfarct patients. Two motion parameters, contraction and rotation, were quantified for each cardiac segment by fitting the proposed model using a non-rigid registration algorithm. The accuracy in motion estimation was compared to a global model approach. Motion parameters extracted from patients were correlated to infarct transmurality assessed with delayed-contrast-enhanced MRI. The proposed segmental model allows markedly improved accuracy in regional motion analysis as compared to the global model for both subject groups (1.22-1.40 mm versus 2.31-2.55 mm error). By end-systole, all healthy segments experienced radial displacement by ~25-35% of the epicardial radius, whereas the 3 short-axis planes rotated differently (basal: 3.3° mid:  -1° and apical:  -4.6°) to create a twisting motion. While systolic contraction showed clear correspondence to infarct transmurality, rotation was nonspecific to either infarct location or transmurality but could indicate the presence of functional abnormality. Regional contraction and rotation derived using this model could potentially aid in the assessment of severity of regional dysfunction of infarcted myocardium.

  20. Stress ventricular function test in conscious, nonthoracotomised dogs to assess cardiac drug efficacy.

    Science.gov (United States)

    French, W J; Averill, W; Ung, S; Laks, M M

    1985-01-01

    The measurement of left ventricular (LV) function is frequently performed in unconscious or thoracotomised animals in the resting state; these conditions may seriously affect the basal haemodynamic state. To assess myocardial function in conscious animals, a technique was developed to place a catheter across the atrial septum into the left ventricle without a thoracotomy. A stress ventricular function test (SVFT) was performed by raising the systemic blood pressure with methoxamine in the conscious dog. In order to demonstrate the effectiveness of the SVFT in the detection of a decrease in ventricular function, a SVFT was performed before and after the acute infusion of verapamil to determine resting and reserve LV function. A slope relating systolic aortic pressure to the LV end-diastolic pressure was obtained in 10 dogs using a low dose (0.005) and in four dogs a high dose (0.01 microgram X kg-1 X min-1) verapamil (V). The mean slope before V was 3.6 +/- 1.2 and after 2.0 +/- 0.92 (p less than 0.001). The day-to-day variability of the SVFT was less than 22% (coefficient of variability). The SVFT is a sensitive, reproducible method to assess resting and increased or decreased myocardial contractility and is useful in selecting appropriate doses of cardiac drugs to determine their effect on the myocardium during acute and chronic infusion studies in the conscious, nonthoracotomised dog. PMID:3986853

  1. Regional assessment of LV wall in infarcted heart using tagged MRI and cardiac modelling

    International Nuclear Information System (INIS)

    A segmental two-parameter empirical deformable model is proposed for evaluating regional motion abnormality of the left ventricle. Short-axis tagged MRI scans were acquired from 10 healthy subjects and 10 postinfarct patients. Two motion parameters, contraction and rotation, were quantified for each cardiac segment by fitting the proposed model using a non-rigid registration algorithm. The accuracy in motion estimation was compared to a global model approach. Motion parameters extracted from patients were correlated to infarct transmurality assessed with delayed-contrast-enhanced MRI. The proposed segmental model allows markedly improved accuracy in regional motion analysis as compared to the global model for both subject groups (1.22–1.40 mm versus 2.31–2.55 mm error). By end-systole, all healthy segments experienced radial displacement by ∼25–35% of the epicardial radius, whereas the 3 short-axis planes rotated differently (basal: 3.3°; mid:  −1° and apical:  −4.6°) to create a twisting motion. While systolic contraction showed clear correspondence to infarct transmurality, rotation was nonspecific to either infarct location or transmurality but could indicate the presence of functional abnormality. Regional contraction and rotation derived using this model could potentially aid in the assessment of severity of regional dysfunction of infarcted myocardium. (paper)

  2. Coronary Flow Reserve as an Index of Cardiac Function in Mice with Cardiovascular Abnormalities

    OpenAIRE

    Hartley, Craig J.; Reddy, Anilkumar K.; Michael, Lloyd H.; Entman, Mark L.; Taffet, George E.

    2009-01-01

    Mice are now commonly used as models of human cardiovascular diseases and conditions, but it is challenging to measure blood flow velocity in small vessels such as coronary arteries. Accordingly, we have developed a method using a 2 mm diameter 20 MHz pulsed Doppler probe applied to the chest of anesthetized mice to measure left main coronary blood flow velocity noninvasively. We also found that coronary flow velocity could be increased from baseline (B) to hyperemic (H) levels by changing th...

  3. Assessment of cardiac function using myocardial perfusion imaging technique on SPECT with 99mTc sestamibi

    Science.gov (United States)

    Gani, M. R. A.; Nazir, F.; Pawiro, S. A.; Soejoko, D. S.

    2016-03-01

    Suspicion on coronary heart disease can be confirmed by observing the function of left ventricle cardiac muscle with Myocardial Perfusion Imaging techniques. The function perfusion itself is indicated by the uptake of radiopharmaceutical tracer. The 31 patients were studied undergoing the MPI examination on Gatot Soebroto Hospital using 99mTc-sestamibi radiopharmaceutical with stress and rest conditions. Stress was stimulated by physical exercise or pharmacological agent. After two hours, the patient did rest condition on the same day. The difference of uptake percentage between stress and rest conditions will be used to determine the malfunction of perfusion due to ischemic or infarct. Degradation of cardiac function was determined based on the image-based assessment of five segments of left ventricle cardiac. As a result, 8 (25.8%) patients had normal myocardial perfusion and 11 (35.5%) patients suspected for having partial ischemia. Total ischemia occurred to 8 (25.8%) patients with reversible and irreversible ischemia and the remaining 4 (12.9%) patients for partial infarct with characteristic the percentage of perfusion ≤50%. It is concluded that MPI technique of image-based assessment on uptake percentage difference between stress and rest conditions can be employed to predict abnormal perfusion as complementary information to diagnose the cardiac function.

  4. CRITICAL ASSESSMENT OF AUTOMATED FLOW CYTOMETRY DATA ANALYSIS TECHNIQUES

    OpenAIRE

    Aghaeepour, Nima; Finak, Greg; ,; Hoos, Holger; Mosmann, Tim R; Gottardo, Raphael; Brinkman, Ryan; Scheuermann, Richard H.

    2013-01-01

    Traditional methods for flow cytometry (FCM) data processing rely on subjective manual gating. Recently, several groups have developed computational methods for identifying cell populations in multidimensional FCM data. The Flow Cytometry: Critical Assessment of Population Identification Methods (FlowCAP) challenges were established to compare the performance of these methods on two tasks – mammalian cell population identification to determine if automated algorithms can reproduce expert manu...

  5. Cardiac dual-source CT for the preoperative assessment of patients undergoing bariatric surgery

    International Nuclear Information System (INIS)

    Aim: To assess the diagnostic value of coronary dual-source computed tomography (DSCT) as a comprehensive, non-invasive tool in the preoperative cardiac evaluation of patients undergoing bariatric surgery. Materials and methods: Thirty consecutive obese [average body mass index (BMI): 45 ± 7.6, range: 35–59] patients (24 women; six men; median age: 52 ± 15 years) were enrolled in this institutional review board (IRB)-approved, Health Insurance Portability and Accountability Act of 1996 (HIPAA)-compliant prospective study. Calcium scoring (CaS) and electrocardiography (ECG)-gated images of the coronary arteries were obtained with a large body habitus protocol (120 kV; 430 mAs; 100 ml iodinated contrast medium at 7 ml/s injection rate) on a DSCT machine. Qualitative (four-point: 1 = excellent to 4 = not delineable) coronary segmental analysis, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) measurements were performed. The presence and degree of vascular disease (four-grade scale: mild to severe) was correlated with CaS and cardiovascular (CV) risk stratification blood tests. In patients with severe stenosis (>70%), findings were compared with cardiac nuclear medicine imaging (single photon-emission computed tomography; SPECT) imaging. Results: The average HR, enhancement, and quality score were 64 ± 7 beats/min, 288 ± 66 HU and 1.8 ± .5, respectively. Ninety-three percent (417/450) of the coronary segments were rated diagnostic. The SNRs and CNRs were 17 ± 9 and 12 ± 7 for the right coronary artery; 17 ± 8 and 12 ± 7 for the left main coronary artery; 16 ± 9 and 11 ± 7 for the left anterior descending coronary artery; and 15 ± 7 and 10 ± 6 for the left circumflex coronary artery. Ten of the 30 patients (33%) demonstrated coronary artery disease (CAD) of which two (6%) showed three-vessel disease. Four (13%) patients showed severe disease: in three of which the presence of significant stenosis was confirmed by SPECT and by catheter

  6. Environmental flow assessments in estuaries related to preference of phytoplankton

    OpenAIRE

    Z. F. Yang; Sun, T; Zhao, R.

    2014-01-01

    We developed an approach to assess environmental flows in estuaries related to preference of phytoplankton considering the complex relationship between hydrological modification and biomass in ecosystems. As a first step, a relationship was established between biomass requirements for organisms of primary and higher nutritional levels based on the principle of nutritional energy flow of ecosystem. Then, diagnostic pigments were employed to represent phytopl...

  7. Environmental flow assessments in estuaries related to preference of phytoplankton

    OpenAIRE

    Z. F. Yang; Sun, T; Zhao, R.

    2014-01-01

    An approach to assess estuarine environmental flow based on phytoplankton preference, including the complex relationships between hydrological modifications and ecosystem biomass, was developed in this study. We initially established a relationship between biomass requirements for primary and higher nutritional level organisms based on the ecosystem nutritional energy flow principles. Subsequently, diagnostic pigments were employed to represent phytoplankton community biomas...

  8. Assessment of cardiac sympathetic nerve activity in children with chronic heart failure using quantitative iodine-123 metaiodobenzylguanidine imaging

    International Nuclear Information System (INIS)

    Cardiac sympathetic nerve activity in children with chronic heart failure was examined by quantitative iodine-123 metaiodobenzylguanidine (MIBG) myocardial imaging in 33 patients aged 7.5±6.1 years (range 0-18 years), including 8 with cardiomyopathy, 15 with congenital heart disease, 3 with anthracycrine cardiotoxicity, 3 with myocarditis, 3 with primary pulmonary hypertension and 1 with Pompe's disease. Anterior planar images were obtained 15 min and 3 hr after the injection of iodine-123 MIBG. The cardiac iodine-123 MIBG uptake was assessed as the heart to upper mediastinum uptake activity ratio of the delayed image (H/M) and the cardiac percentage washout rate (%WR). The severity of chronic heart failure was class I (no medication) in 8 patients, class II (no symptom with medication) in 9, class III (symptom even with medication) in 10 and class IV (late cardiac death) in 6. H/M was 2.33±0.22 in chronic heart failure class I, 2.50±0.34 in class II, 1.95±0.61 in class III, and 1.39±0.29 in class IV (p<0.05). %WR was 24.8±12.8% in chronic heart failure class I, 23.3±10.2% in class II, 49.2±24.5% in class III, and 66.3±26.5% in class IV (p<0.05). The low H/M and high %WR were proportionate to the severity of chronic heart failure. Cardiac iodine-123 MIBG showed cardiac adrenergic neuronal dysfunction in children with severe chronic heart failure. Quantitative iodine-123 MIBG myocardial imaging is clinically useful as a predictor of therapeutic outcome and mortality in children with chronic heart failure. (author)

  9. Assessing the performance of curtain flow first generation silica monoliths.

    Science.gov (United States)

    Soliven, Arianne; Foley, Dominic; Pereira, Luisa; Dennis, Gary R; Shalliker, R Andrew; Cabrera, Karin; Ritchie, Harald; Edge, Tony

    2014-07-18

    Analytical scale active flow technology first generation silica monolithic columns kitted out in curtain flow mode of operation were studied for the first time. A series of tests were undertaken assessing the column efficiency, peak asymmetry and detection sensitivity. Two curtain flow columns were tested, one with a fixed outlet ratio of 10% through the central exit port, the other with 30%. Tests were carried out using a wide range in inlet flow segmentation ratios. The performance of the curtain flow columns were compared to a conventional monolithic column. The gain in theoretical plates achieved in the curtain flow mode of operation was as much as 130%, with almost Gaussian bands being obtained. Detection sensitivity increased by as much as 250% under optimal detection conditions. The permeability advantage of the monolithic structure together with the active flow technology makes it a priceless tool for high throughput, sensitive, low detection volume analyses. PMID:24906299

  10. Cerebral blood flow during cardiopulmonary bypass in pediatric cardiac surgery: the role of transcranial Doppler – a systematic review of the literature

    Directory of Open Access Journals (Sweden)

    Sanders Stephen P

    2006-12-01

    Full Text Available Abstract Background Transcranial Doppler Ultrasound (TCD is a sensitive, real time tool for monitoring cerebral blood flow velocity (CBFV. This technique is fast, accurate, reproducible and noninvasive. In the setting of congenital heart surgery, TCD finds application in the evaluation of cerebral blood flow variations during cardiopulmonary bypass (CPB. Methodology We performed a search on human studies published on the MEDLINE using the keyword "trans cranial Doppler" crossed with "pediatric cardiac surgery" AND "cardio pulmonary by pass", OR deep hypothermic cardiac arrest", OR "neurological monitoring". Discussion Current scientific evidence suggests a good correlation between changes in cbral blood flow and mean cerebral artery (MCA blood flow velocity. The introduction of Doppler technology has allowed an accurate monitorization of cerebral blood flow (CBF during circulatory arrest and low-flow CPB. TCD has also been utilized in detecting cerebral emboli, improper cannulation or cross clamping of aortic arch vessels. Limitations of TCD routine utilization are represented by the need of a learning curve and some experience by the operators, as well as the need of implementing CBF informations with, for example, data on brain tissue oxygen delivery and consumption. Conclusion In this light, TCD plays an essential role in multimodal neurological monitorization during CPB (Near Infrared Spectroscopy, TCD, processed electro encephalography that, according to recent studies, can help to significantly improve neurological outcome after cardiac surgery in neonates and pediatric patients.

  11. Cardiac Pacemakers

    International Nuclear Information System (INIS)

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

  12. GULLY-SPECIFIC DEBRIS FLOW HAZARD ASSESSMENT IN CHINA

    Institute of Scientific and Technical Information of China (English)

    LIU Xi-lin

    2003-01-01

    Techniques of gully-specific debris flow hazard assessment developed in four periods since the end of the1980s have been discussed in the present paper. The improvement for the empirical assessment method is the sectional-ized function transformation for the factor value, rather than the classified logical transformation. The theoretical equationof the gully-specific debris flow hazard is expressed as the definite integral of an exponential function and its numericalsolution is expressed by the Poisson Limit Equation. Current methods for assessment of debris flow hazard in China arestill valid and practical. The further work should be put on the study of the reliability (or unc ertainty) of the techniques.For the future, we should give a high priority to the relationship between debris flow magnitude and its frequency of occur-rence, make more developments of prediction model on debris flow magnitude, so as to finally reach the goal of assessingthe hazard of debris flow by theoretical model, and realize both actuality assessment and prediction appraisal of debris flow.

  13. Functional cardiac MRI for assessment of aortic valve disease; Aortenklappenstenose im MRT mit Dynamik und 3D

    Energy Technology Data Exchange (ETDEWEB)

    Sagmeister, F.; Ritter, C.; Machann, W.; Koestler, H.; Hahn, D.; Beer, M. [Universitaetsklinikum Wuerzburg, Institut fuer Roentgendiagnostik, Wuerzburg (Germany); Herrmann, S.; Voelker, W.; Weidemann, F. [Universitaetsklinikum Wuerzburg, Medizinische Klinik I, Wuerzburg (Germany)

    2010-06-15

    Aortic valve disease shows a rising incidence with the increasing mean age of Western populations. The detection of hemodynamic parameters, which transcends the mere assessment of valve morphology, has an important future potential concerning classification of the severity of disease. MRI allows a non-invasive and a spatially flexible view of the aortic valve and the adjacent anatomic region, left ventricular outflow tract (LVOT) and ascending aorta. Moreover, the technique allows the determination of functional hemodynamic parameters, such as flow velocities and effective orifice areas. The new approach of a serial systolic planimetry velocity-encoded MRI sequence (VENC-MRI) facilitates the sizing of blood-filled cardiac structures with the registration of changes in magnitude during systole. Additionally, the subvalvular VENC-MRI measurements improve the clinically important exact determination of the LVOT area with respect to its specific eccentric configuration and its systolic deformity. (orig.) [German] Erworbene Erkrankungen der Aortenklappe wie die Aortenklappenstenose zeigen mit zunehmender Alterungstendenz unserer Gesellschaft eine ansteigende Inzidenz. Die Erfassung ueber die reine Klappenmorphologie hinausgehender haemodynamischer Parameter hat ein wichtiges zukuenftiges Potenzial zur Schweregradeinschaetzung. Die MRT erlaubt eine nichtinvasive und raeumlich flexible Darstellung der Aortenklappe sowie ihrer benachbarten anatomischen Strukturen (linksventrikulaerer Ausflusstrakt/LVOT, Aorta ascendens). Darueber hinaus ist eine Bestimmung funktioneller haemodynamischer Parameter wie Flussgeschwindigkeiten und effektiven Oeffnungsflaechen (EOeF) moeglich. Der neue Ansatz einer seriellen Planimetrie geschwindigkeitskodierter MRT-Sequenzen (Velocity-encoding- [VENC-]MRT) erlaubt die Groessenbestimmung flussdurchstroemter kardialer Strukturen und die Aufzeichnung ihrer dynamischen Groessenveraenderung waehrend der Systole. Zusaetzlich ermoeglicht die

  14. Detecting drug-induced prolongation of the QRS complex: New insights for cardiac safety assessment

    International Nuclear Information System (INIS)

    Background: Drugs slowing the conduction of the cardiac action potential and prolonging QRS complex duration by blocking the sodium current (INa) may carry pro-arrhythmic risks. Due to the frequency-dependent block of INa, this study assesses whether activity-related spontaneous increases in heart rate (HR) occurring during standard dog telemetry studies can be used to optimise the detection of class I antiarrhythmic-induced QRS prolongation. Methods: Telemetered dogs were orally dosed with quinidine (class Ia), mexiletine (class Ib) or flecainide (class Ic). QRS duration was determined standardly (5 beats averaged at rest) but also prior to and at the plateau of each acute increase in HR (3 beats averaged at steady state), and averaged over 1 h period from 1 h pre-dose to 5 h post-dose. Results: Compared to time-matched vehicle, at rest, only quinidine and flecainide induced increases in QRS duration (Emax 13% and 20% respectively, P < 0.01–0.001) whereas mexiletine had no effect. Importantly, the increase in QRS duration was enhanced at peak HR with an additional effect of + 0.7 ± 0.5 ms (quinidine, NS), + 1.8 ± 0.8 ms (mexiletine, P < 0.05) and + 2.8 ± 0.8 ms (flecainide, P < 0.01) (calculated as QRS at basal HR-QRS at high HR). Conclusion: Electrocardiogram recordings during elevated HR, not considered during routine analysis optimised for detecting QT prolongation, can be used to sensitise the detection of QRS prolongation. This could prove useful when borderline QRS effects are detected. Analysing during acute increases in HR could also be useful for detecting drug-induced effects on other aspects of cardiac function. -- Highlights: ► We aimed to improve detection of drug-induced QRS prolongation in safety screening. ► We used telemetered dogs to test class I antiarrhythmics at low and high heart rate. ► At low heart rate only quinidine and flecainide induced an increase in QRS duration. ► At high heart rate the effects of two out of three

  15. Detecting drug-induced prolongation of the QRS complex: New insights for cardiac safety assessment

    Energy Technology Data Exchange (ETDEWEB)

    Cros, C., E-mail: caroline.cros@hotmail.co.uk [Safety Pharmacology, Global Safety Assessment, Safety Assessment UK, AstraZeneca R and D, Alderley Park, Macclesfield, SK10 4TG (United Kingdom); Skinner, M., E-mail: Matthew.Skinner@astrazeneca.com [Safety Pharmacology, Global Safety Assessment, Safety Assessment UK, AstraZeneca R and D, Alderley Park, Macclesfield, SK10 4TG (United Kingdom); Moors, J. [Safety Pharmacology, Global Safety Assessment, Safety Assessment UK, AstraZeneca R and D, Alderley Park, Macclesfield, SK10 4TG (United Kingdom); Lainee, P. [Sanofi-Aventis R and D, 371, rue du Pr Joseph Blayac, 34184 Montpellier Cedex 04 (France); Valentin, J.P. [Safety Pharmacology, Global Safety Assessment, Safety Assessment UK, AstraZeneca R and D, Alderley Park, Macclesfield, SK10 4TG (United Kingdom)

    2012-12-01

    Background: Drugs slowing the conduction of the cardiac action potential and prolonging QRS complex duration by blocking the sodium current (I{sub Na}) may carry pro-arrhythmic risks. Due to the frequency-dependent block of I{sub Na}, this study assesses whether activity-related spontaneous increases in heart rate (HR) occurring during standard dog telemetry studies can be used to optimise the detection of class I antiarrhythmic-induced QRS prolongation. Methods: Telemetered dogs were orally dosed with quinidine (class Ia), mexiletine (class Ib) or flecainide (class Ic). QRS duration was determined standardly (5 beats averaged at rest) but also prior to and at the plateau of each acute increase in HR (3 beats averaged at steady state), and averaged over 1 h period from 1 h pre-dose to 5 h post-dose. Results: Compared to time-matched vehicle, at rest, only quinidine and flecainide induced increases in QRS duration (E{sub max} 13% and 20% respectively, P < 0.01–0.001) whereas mexiletine had no effect. Importantly, the increase in QRS duration was enhanced at peak HR with an additional effect of + 0.7 ± 0.5 ms (quinidine, NS), + 1.8 ± 0.8 ms (mexiletine, P < 0.05) and + 2.8 ± 0.8 ms (flecainide, P < 0.01) (calculated as QRS at basal HR-QRS at high HR). Conclusion: Electrocardiogram recordings during elevated HR, not considered during routine analysis optimised for detecting QT prolongation, can be used to sensitise the detection of QRS prolongation. This could prove useful when borderline QRS effects are detected. Analysing during acute increases in HR could also be useful for detecting drug-induced effects on other aspects of cardiac function. -- Highlights: ► We aimed to improve detection of drug-induced QRS prolongation in safety screening. ► We used telemetered dogs to test class I antiarrhythmics at low and high heart rate. ► At low heart rate only quinidine and flecainide induced an increase in QRS duration. ► At high heart rate the effects of two

  16. Assessment of potential drug–drug interactions and its associated factors in the hospitalized cardiac patients

    Directory of Open Access Journals (Sweden)

    Ghulam Murtaza

    2016-03-01

    Full Text Available Drug–drug interactions (DDIs may result in the alteration of therapeutic response. Sometimes they may increase the untoward effects of many drugs. Hospitalized cardiac patients need more attention regarding drug–drug interactions due to complexity of their disease and therapeutic regimen. This research was performed to find out types, prevalence and association between various predictors of potential drug–drug interactions (pDDIs in the Department of Cardiology and to report common interactions. This study was performed in the hospitalized cardiac patients at Ayub Teaching Hospital, Abbottabad, Pakistan. Patient charts of 2342 patients were assessed for pDDIs using Micromedex® Drug Information. Logistic regression was applied to find predictors of pDDIs. The main outcome measure in the study was the association of the potential drug–drug interactions with various factors such as age, gender, polypharmacy, and hospital stay of the patients. We identified 53 interacting-combinations that were present in total 5109 pDDIs with median number of 02 pDDIs per patient. Overall, 91.6% patients had at least one pDDI; 86.3% were having at least one major pDDI, and 84.5% patients had at least one moderate pDDI. Among 5109 identified pDDIs, most were of moderate (55% or major severity (45%; established (24.2%, theoretical (18.8% or probable (57% type of scientific evidence. Top 10 common pDDIs included 3 major and 7 moderate interactions. Results obtained by multivariate logistic regression revealed a significant association of the occurrence of pDDIs in patient with age of 60 years or more (p < 0.001, hospital stay of 7 days or longer (p < 0.001 and taking 7 or more drugs (p < 0.001. We found a high prevalence for pDDIs in the Department of Cardiology, most of which were of moderate severity. Older patients, patients with longer hospital stay and with elevated number of prescribed drugs were at higher risk of pDDIs.

  17. Clinical Application of Cine-MRI in the Visual Assessment of Mitral Regurgitation Compared to Echocardiography and Cardiac Catheterization

    OpenAIRE

    Heitner, John; Bhumireddy, Geetha P; Crowley, Anna Lisa; Weinsaft, Jonathan; Haq, Salman A.; Klem, Igor; Kim, Raymond J; Jollis, James G.

    2012-01-01

    Background Detecting and quantifying the severity of mitral regurgitation is essential for risk stratification and clinical decision-making regarding timing of surgery. Our objective was to assess specific visual parameters by cine-magnetic resonance imaging (MRI) in the determination of the severity of mitral regurgitation and to compare it to previously validated imaging modalities: echocardiography and cardiac ventriculography. Methods The study population consisted of 68 patients who unde...

  18. Can Stress Echocardiography Compete with Perfusion Scintigraphy in the Detection of Coronary Artery Disease and Cardiac Risk Assessment?

    OpenAIRE

    Geleijnse, Marcel; Elhendy, Abdou

    2000-01-01

    textabstractAims: The aim of this review was to define the place of stress echocardiography in the context of perfusion scintigraphy for the detection of coronary artery disease (CAD) and the assessment of cardiac risk. Stress echocardiography has the benefits of widespread availability, relatively low cost, portability, absence of radiation, and the determination of the ischaemic threshold. However, the echocardiographic windows are variable, sometimes with poor echogenicity, and interpretat...

  19. Cardiac function during exercise in patients with coronary bypass surgery assessed by continuous ventricular function monitoring

    International Nuclear Information System (INIS)

    The response of left ventricular function during exercise and recovery after exercise was assessed in 52 patients with coronary artery bypass surgery by means of a radionuclide continuous ventricular function monitor. This system consists of 2 radionuclide detectors, recorder and a computer. After the equilibration of 20 mCi technetium 99m-labeled autologaous red blood cells into the intravascular space, the beat by beat radionuclide data were summed for 20-sec intervals to measure left ventricular ejection fraction (EF). Before surgery, the mean EF decreased with exercise from 51±9% to 45±11% (p<0.001). Cardiac response was divided into 4 types according to the profiles of the EFs during exercise. In 6 patients, EF continued to increase until maximal exercise (type A). In 10 patients, EF initially increased and then decreased in late exercise stages (type B). In 9 patients, EF did not change significantly during exercise (type C). In 27 patients, EF decreased throughout exercise (type D). After surgery, the mean EF increased with exercise from 53±10% to 60±13% (p<0.001). Thirty-five patients showed type A, 9 type B, 5 type C, and 3 type D. Two type D and 5 type B patients had occluded grafts or ungrafted coronary arteries. Four patients with complete revascularization including an internal thoracic artery and saphenous vein grafts showed type B. Three patients with extensive infarction and poor left ventricular function showed type C. The time interval between the end of exercise and the point of maximal EF during recovery after exercise was reduced from 168 sec before surgery to 98 sec after surgery (p<0.001). The continuous ventricular function monitor elucidated changes in left ventricular function during exercise and recovery after exercise and provided a new aspect of assessing the effects of coronary bypass surgery. (author)

  20. Assessing Physical Activity as a Core Component in Cardiac Rehabilitation: A POSITION STATEMENT OF THE AMERICAN ASSOCIATION OF CARDIOVASCULAR AND PULMONARY REHABILITATION.

    Science.gov (United States)

    Kaminsky, Leonard A; Brubaker, Peter H; Guazzi, Marco; Lavie, Carl J; Montoye, Alexander H K; Sanderson, Bonnie K; Savage, Patrick D

    2016-01-01

    Physical inactivity is a well-established major risk factor for cardiovascular disease. As such, physical activity counseling is 1 of the 10 core components of cardiac rehabilitation/secondary prevention programs recommended by the American Heart Association and the American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR). In addition, the ability to perform a physical activity assessment and report outcomes is 1 of the 10 core competencies of cardiac rehabilitation/secondary prevention professionals published by the AACVPR. Unfortunately, standardized procedures for physical activity assessment of cardiac rehabilitation patients have not been developed and published. Thus, the objective of this AACVPR statement is to provide an overview of physical activity assessment concepts and procedures and to provide a recommended approach for performing a standardized assessment of physical activity in all comprehensive cardiac rehabilitation programs following the core components recommendations. PMID:27307067

  1. Cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Dewey, Marc [Charite - Universitaetsmedizin Berlin (Germany). Inst. fuer Radiologie

    2011-07-01

    Computed tomography of the heart has become a highly accurate diagnostic modality that is attracting increasing attention. This extensively illustrated book aims to assist the reader in integrating cardiac CT into daily clinical practice, while also reviewing its current technical status and applications. Clear guidance is provided on the performance and interpretation of imaging using the latest technology, which offers greater coverage, better spatial resolution, and faster imaging. The specific features of scanners from all four main vendors, including those that have only recently become available, are presented. Among the wide range of applications and issues to be discussed are coronary artery bypass grafts, stents, plaques, and anomalies, cardiac valves, congenital and acquired heart disease, and radiation exposure. Upcoming clinical uses of cardiac CT, such as plaque imaging and functional assessment, are also explored. (orig.)

  2. Environmental flow assessment for river Trebizat, BiH

    Science.gov (United States)

    Smolar-Zvanut, N.; Kupusovic, E.; Vucijak, B.; Mijatovic, A.; Grizelj, Z.; Antonelli, F.

    2009-04-01

    The alteration of the water flow downstream of dams is one of the most stressful factors influencing the aquatic and riverine ecosystem. The environmental flow assessment is a tool for finding the balance between water use by humans and nature and ensuring a long-term and good quality water supply both for human purposes and for ecosystems. In 2007/08 WWF has implemented a project in the Neretva basin (Bosnia and Herzegovina) with a focus on environmental flow evaluation for the river Trebizat, located in the western region of Herzegovina. The water regime of the Trebizat river is affected by the abstraction of its water for hydropower plants, irrigation and fish farming not to mention pollution problems. The Trebizat river flows through an area of remarkable ecological value hosting also protected areas (the travertine-formation around Kravice waterfall). The main aim of this paper is to present the results of the application of a methodology for environmental flow assessment, namely the GEP methodology (guaranteed ecological flow). It belongs to the category of hydrological environmental flow assessment methods and the test was done to assess the environmental flow in the river Trebizat. Using existing hydrological data as well as samples specifically collected on the field, the environmental flow was assessed applying the GEP methodology. Additionally, instream ecological values and critical parameters for environmental flow assessment were evaluated. The area was assessed in terms of its geography, climate conditions, historic heritage of the river, demography, geology of the river and its tributaries, river hydrology and morphology, ecological characteristics, river pollution, river use and river management. At five selected sampling sites along the Trebizat river, additional data on macrophytes, phytobenthos and physico-chemical parameters were collected and analysed. Although there have been many negative impacts in recent years on the Trebizat river, the

  3. Assessment of factors that influence weaning from long-term mechanical ventilation after cardiac surgery

    OpenAIRE

    Emília Nozawa; Eliane Kobayashi; Marta Erika Matsumoto; Maria Ignêz Zanetti Feltrim; Maria José Carvalho Carmona; José Otávio Costa Auler Júnior

    2003-01-01

    OBJECTIVE: To analyze parameters of respiratory system mechanics and oxygenation and cardiovascular alterations involved in weaning tracheostomized patients from long-term mechanical ventilation after cardiac surgery. METHODS: We studied 45 patients in their postoperative period of cardiac surgery, who required long-term mechanical ventilation for more than 10 days and had to undergo tracheostomy due to unsuccessful weaning from mechanical ventilation. The parameters of respiratory system mec...

  4. Cost and effectiveness assessment of cardiac rehabilitation for dialysis patients following coronary bypass

    OpenAIRE

    Huang, Yijian; Zhang, Rebecca; Culler, Steven; Kutner, Nancy

    2008-01-01

    Dialysis patients have a high risk of cardiovascular disease. In the general population, cardiac rehabilitation is recommended as a standard component of care and is covered by Medicare for patients who have undergone coronary artery bypass grafting (CABG). Previous investigation demonstrated survival benefit of cardiac rehabilitation in dialysis patients. This study investigated its impact on Medicare expenditure and its cost effectiveness. A cohort of 4,324 end-stage renal disease (ESRD) pa...

  5. Assessing future changes in pan-European environmental flows

    Science.gov (United States)

    Laize, C.; Hannah, D. M.

    2011-12-01

    The potential river flow-driven impact of change on aquatic and riparian ecosystems at the pan-European scale under various climatological and development scenarios was assessed using a methodology based conceptually on the Range of Variability Approach (RVA) using the Indicators of Hydrological Alteration (IHA): a desk-top technique for assessing if environmental flow requirements. This paper presents an adaptation of the IHA approach using monthly flows. European and Mediterranean river networks were modelled as ~35,000 cells (0.5° longitude x 0.5° latitude). For each cell, modelled monthly flows were generated for an ensemble of 10 future climate change scenarios. These scenarios consist of combinations of two climate scenarios (IPCM4 and MIMR) and four socio-economic water-use scenarios (each with a main driver of economy, policy, security, or sustainability), projected for 2050s. IHA-styled statistics were calculated. By tailoring the RVA, acceptable baseline environmental flow ranges and departures from these of the projected hydrological regimes were assessed and coded using a traffic-light system (green for environmental flows met, amber minor variation, red major variation). For the first time, the results show spatial patterns of flow change and associated potential river ecosystem impacts across the wider European continent. Importantly, the findings indicate that climate change may be a more influential driver than water-use change in determining future river ecosystem health . Patterns were also investigated against broad basin types to identify which are most or least at risk.

  6. Cardiac MRI assessment of right ventricular function: impact of right bundle branch block on the evaluation of cardiac performance parameters

    International Nuclear Information System (INIS)

    Right ventricular (RV) function represents a prognostic marker in patients with corrected congenital heart disease. In up to 80 % of these patients, right branch bundle block (RBBB) exists and leads to asynchronous ventricular contraction. The aim of this retrospective study was to evaluate the change of RV performance parameters considering delayed RV end-systolic contraction. RV volumes of 33 patients were assessed twice: 1) not taking account of RBBB (group I), and 2) considering RBBB (group II). According to the RV ejection fraction (EF) for both groups, RV function was classified in different categories (>50 % = normal, 40-50 % = mildly-, 30-40 % = moderately-, <30 % = severely-reduced). The mean time difference between maximal systolic contraction of the septum and RV free wall was 90.7 ms ± 42.6. Consequently, RV end-systolic volume was significantly decreased in group II (p < 0.001). Accordingly, RV stroke volume and RV EF were significantly higher in group II (p < 0.001). There was also a significant change in the assessment of RV function (p < 0.02). RBBB induced delayed RV contraction can be detected at CMR. Ignoring the RV physiology in RBBB patients leads to a statistically significant underscoring of RV performance parameters. (orig.)

  7. Cardiac MRI assessment of right ventricular function: impact of right bundle branch block on the evaluation of cardiac performance parameters

    Energy Technology Data Exchange (ETDEWEB)

    Marterer, Robert; Tschauner, Sebastian; Sorantin, Erich [Medical University of Graz, Division of Pediatric Radiology, Department of Radiology, Graz (Austria); Zeng, Hongchun [First Affiliated Hospital of Xinjiang Medical University, Department of Ultrasonography, Urumqi (China); Koestenberger, Martin [Medical University of Graz, Division of Pediatric Cardiology, Department of Pediatrics and Adolescent Medicine, Graz (Austria)

    2015-12-15

    Right ventricular (RV) function represents a prognostic marker in patients with corrected congenital heart disease. In up to 80 % of these patients, right branch bundle block (RBBB) exists and leads to asynchronous ventricular contraction. The aim of this retrospective study was to evaluate the change of RV performance parameters considering delayed RV end-systolic contraction. RV volumes of 33 patients were assessed twice: 1) not taking account of RBBB (group I), and 2) considering RBBB (group II). According to the RV ejection fraction (EF) for both groups, RV function was classified in different categories (>50 % = normal, 40-50 % = mildly-, 30-40 % = moderately-, <30 % = severely-reduced). The mean time difference between maximal systolic contraction of the septum and RV free wall was 90.7 ms ± 42.6. Consequently, RV end-systolic volume was significantly decreased in group II (p < 0.001). Accordingly, RV stroke volume and RV EF were significantly higher in group II (p < 0.001). There was also a significant change in the assessment of RV function (p < 0.02). RBBB induced delayed RV contraction can be detected at CMR. Ignoring the RV physiology in RBBB patients leads to a statistically significant underscoring of RV performance parameters. (orig.)

  8. Holographic velocimetry for evaluation of cardiac valves

    International Nuclear Information System (INIS)

    Holographic velocimetry is a noninvasive method for fluid flow analysis, making it possible to determine flow field characteristics for any instant in a flow cycle. The use of holographic velocimetry to assess prosthetic heart valve performance has never before been accomplished. However, it seems readily apparent that much pertinent information will be gained from it, such as the exact location and quantitative analysis of stagnation zones, high shear and high velocity regions. A comparison of the results from holographic velocimetry are made with those of laser Doppler anemometry. The first study deals with steady state flow analysis at peak systolic flow rates for normal cardiac outputs

  9. Early assessment of sub-clinical cardiac involvement in systemic sclerosis (SSc) using delayed enhancement cardiac magnetic resonance (CE-MRI)

    Energy Technology Data Exchange (ETDEWEB)

    Di Cesare, Ernesto, E-mail: ernesto.dicesare@cc.univaq.it [Department of Radiology, University of L’Aquila, Via Vetoio 1, 67100 L’Aquila (Italy); Battisti, Sara; Di Sibio, Alessandra [Department of Radiology, University of L’Aquila, Via Vetoio 1, 67100 L’Aquila (Italy); Cipriani, Paola; Giacomelli, Roberto; Liakouli, Vasiliky; Ruscitti, Piero [Rheumatology Clinic, Department of Internal Medicine and Public Health, University of L’Aquila, L’Aquila (Italy); Masciocchi, Carlo [Department of Radiology, University of L’Aquila, Via Vetoio 1, 67100 L’Aquila (Italy)

    2013-06-15

    Objectives: Systemic sclerosis heart involvement (SHI) is one of systemic sclerosis (SSc) most frequent complications, both in diffuse (dcSSc) and limited (lcSSc) cutaneous forms of disease. Nowadays, SHI is a major factor decreasing SSc survival rate because, when clinically evident, is associated with 70% of mortality at 5 years. SHI shows different forms, primary and/or secondary. Primary myocardial SHI is characterized by fibrosis. Aim of our study is to assess the presence and pattern of fibrosis as detected by cardiac magnetic resonance (CMR) in systemic sclerosis. Methods: In this study, we used CE-MRI (contrast enhanced-MRI) in 58 female SSc patients. Images were evaluated to obtain functional parameters and to see presence, location and pattern (nodular, linear or diffuse) of myocardial LE, sign of fibrosis. CE-MRI findings were correlated with patients clinical setting. Results: Myocardial fibrosis was detected in 25 of 58 patients (43%). The main finding observed in 16 of these 25 patients was a late enhancement showing a linear pattern, without coronary distribution and sparing the sub-endocardial myocardial layers. A patchy nodular enhancement pattern was observed in 9 patients (36%). Patients with linear pattern presented dcSSc, on the contrary patients with nodular LE displayed the lcSSc form. Conclusions: This study shows that CE-MRI is a reliable technique to detect SHI earlier than other methods. SHI increase passive myocardial stiffness, proportional to collagen deposition degree, leading to cardiac remodelling with possible development of heart failure, even with normal ejection fraction. An early treatment of SHI might improve SSc patients outcome.

  10. Early assessment of sub-clinical cardiac involvement in systemic sclerosis (SSc) using delayed enhancement cardiac magnetic resonance (CE-MRI)

    International Nuclear Information System (INIS)

    Objectives: Systemic sclerosis heart involvement (SHI) is one of systemic sclerosis (SSc) most frequent complications, both in diffuse (dcSSc) and limited (lcSSc) cutaneous forms of disease. Nowadays, SHI is a major factor decreasing SSc survival rate because, when clinically evident, is associated with 70% of mortality at 5 years. SHI shows different forms, primary and/or secondary. Primary myocardial SHI is characterized by fibrosis. Aim of our study is to assess the presence and pattern of fibrosis as detected by cardiac magnetic resonance (CMR) in systemic sclerosis. Methods: In this study, we used CE-MRI (contrast enhanced-MRI) in 58 female SSc patients. Images were evaluated to obtain functional parameters and to see presence, location and pattern (nodular, linear or diffuse) of myocardial LE, sign of fibrosis. CE-MRI findings were correlated with patients clinical setting. Results: Myocardial fibrosis was detected in 25 of 58 patients (43%). The main finding observed in 16 of these 25 patients was a late enhancement showing a linear pattern, without coronary distribution and sparing the sub-endocardial myocardial layers. A patchy nodular enhancement pattern was observed in 9 patients (36%). Patients with linear pattern presented dcSSc, on the contrary patients with nodular LE displayed the lcSSc form. Conclusions: This study shows that CE-MRI is a reliable technique to detect SHI earlier than other methods. SHI increase passive myocardial stiffness, proportional to collagen deposition degree, leading to cardiac remodelling with possible development of heart failure, even with normal ejection fraction. An early treatment of SHI might improve SSc patients outcome

  11. Hybrid cardiac SPECT/64-slice CTA-derived LV function parameters: Correlation and reproducibility assessment

    International Nuclear Information System (INIS)

    The purpose of this study is to define the relationship between SPECT and CTA measured parameters of left ventricular (LV) function and volumes obtained in a single session using SPECT/64-slice CT hybrid imaging device, and in addition, to assess the reproducibility of LV parameters measured using 64-slice CTA. Materials and methods: Seventy-six patients with suspected or known coronary artery disease underwent cardiac CTA and GSPECT in one session using a hybrid SPECT/CT device. LV end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) were measured on each component of the hybrid device. For the CTA component, these parameters were re-measured by the same investigator and by a second investigator with an interval of 3-54 weeks. Corresponding GSPECT and CTA measured parameters were compared. For CTA, intra-observer and inter-observer variability of LV function and volume measurements were calculated. Results: A very good correlation was found between the GSPECT and CTA measured LVEF (r = 0.81), ESV (r = 0.90) and EDV (r = 0.82). There was a small positive difference by CTA measured LVEF (3.9 ± 14.2%), and more prominent positive differences by CTA measured ESV and EDV (9.8 ± 14.8 and 44.9 ± 23.1 cm3, respectively). There was excellent reproducibility in the measurements of all parameters with very low intra- and inter-observer variability (r = 0.93 for EF and 0.98 for EDV and ESV). Conclusions: Although a good correlation was found between the EF measurements obtained from CTA and SPECT, interchangeable use of EF measurements between the two modalities should be done cautiously and interchangeable use of LV EDV and ESV should be avoided.

  12. Risk assessment of debris flow hazards in natural slope

    Science.gov (United States)

    Choi, Junghae; Chae, Byung-gon; Liu, Kofei; Wu, Yinghsin

    2016-04-01

    The study area is located at north-east part of South Korea. Referring to the map of landslide sus-ceptibility (KIGAM, 2009) from Korea Institute of Geoscience and Mineral Resources (KIGAM for short), there are large areas of potential landslide in high probability on slope land of mountain near the study area. Besides, recently some severe landslide-induced debris flow hazards occurred in this area. So this site is convinced to be prone to debris flow haz-ards. In order to mitigate the influence of hazards, the assessment of potential debris flow hazards is very important and essential. In this assessment, we use Debris-2D, debris flow numerical program, to assess the potential debris flow hazards. The worst scenario is considered for simulation. The input mass sources are determined using landslide susceptibility map. The water input is referred to the daily accumulative rainfall in the past debris flow event in study area. The only one input material property, i.e. yield stress, is obtained using calibration test. The simulation results show that the study area has po-tential to be impacted by debris flow. Therefore, based on simulation results, to mitigate debris flow hazards, we can propose countermeasures, including building check dams, constructing a protection wall in study area, and installing instruments for active monitoring of debris flow hazards. Acknowledgements:This research was supported by the Public Welfare & Safety Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Science, ICT & Future Planning (NRF-2012M3A2A1050983)

  13. Cardiac status assessment with a multi-signal device for improved home-based congestive heart failure management.

    Science.gov (United States)

    Muehlsteff, Jens; Carvalho, Paulo; Henriques, Jorge; Paiva, Rui P; Reiter, Harald

    2011-01-01

    State-of-the-Art disease management for Congestive Heart Failure (CHF) patients is still based on easy-to-acquire measures such as heart rate (HR), weight and blood pressure (BP). However, these measures respond late to changes of the patient health status and provide limited information to personalize and adapt medication therapy. This paper describes our concept called "Cardiac Status Assessment" we have been investigating within the European project "HeartCycle" towards next-generation home-based disease management of CHF. In our concept we analyze non-invasive surrogate measures of the cardio-vascular function in particular systolic time intervals and pulse wave characteristics to estimate Cardiac Output (CO) and Systemic Vascular Resistance (SVR) both are established clinical measures. We discuss the underlying concept, a developed measurement system and first results. PMID:22254450

  14. Research on Standard Flow for materials life cycle assessment

    Institute of Scientific and Technical Information of China (English)

    DI Xiang-hua; NIE Zuo-ren; WANG Zhi-hong; ZUO Tie-yong

    2004-01-01

    For the sake of objectivity of the interpretation in life cycle assessment (LCA), the concept and the design proposal of Standard Flow were put forward. Standard Flow was defined as the collection of related environmental load parameters that represent the specific development degree of certain industrial process(es) by the function unit. A novel methodological approach called the Standard Flow Comparing, was developed for LCA. The indicator for potential of process improvement and its weighting factor were derived. To a certain degree the problem of the identification and selection of process development objects in LCA was solved. The concept of Standard Flow and the method of Standard Flow Comparing are introduced, formulized and analyzed.

  15. CT fractional flow reserve: the next level in non-invasive cardiac imaging

    OpenAIRE

    Meijs, M.F.L.; Cramer, M. J.; El Aidi, H.; Doevendans, P.A.

    2012-01-01

    The haemodynamic effect of a coronary artery stenosis is a better predictor of prognosis than anatomical lumen obstruction. Until recently, no individual non-invasive test could provide both accurate coronary anatomy and lesion-specific myocardial ischaemia. However, computer tomography (CT) fractional flow reserve, which can be calculated from a standard CT coronary angiogram, was recently demonstrated to accurately detect and rule out the haemodynamic significance of individual coronary art...

  16. Changes in cardiac output and tibial artery flow during and after progressive LBNP

    Science.gov (United States)

    1980-01-01

    A 3.0 MHz Pulsed Doppler velocity meter (PD) was used to determine blood velocities in the ascending aorta from the suprasternal notch before, during and after progressive 5 min stages of lower body negative pressure (LBNP) in 7 subjects. Changes in stroke volume were calculated from the systolic velocity integrals. A unique 20 MHz PD was used to estimate bloodflow in the posterior tibial artery. With -20 torr mean stroke volume fell 11% and then continued to decline by 48% before LBNP was terminated. Mean tibial flow fell progressively with LBNP stress, due to an increase in reverse flow component and a reduction in peak forward flow and diameter. Stroke volume increased and heart rate fell dramatically during the first 15 sec of recovery. The LBNP was terminated early in 2 subjects because of vasovagal symptons (V). During V the stroke volume rose 86% which more than compensated for the drop in heart rate. This implies that V is accompanied by a paradoxical increase in venous return and that the reduction in HR is the primary cardiovascular event. During the first 15 sec of recovery these 2 subjects had a distinctive marked rise to heart rate reminiscent of the Bainbridge reflex.

  17. Autonomic Dysfunction Predicts Early Cardiac Affection in Patients with Systemic Sclerosis

    OpenAIRE

    Othman, Khaled M.; Naglaa Youssef Assaf; Hanan Mohamed Farouk; Iman M. Aly Hassan

    2010-01-01

    Objective: To detect the early preclinical alterations in cardiac autonomic control as well as altered cardiac function in systemic sclerosis (SSc) patients and their relevance to the clinical features of the disease using noninvasive methods. Methods: 30 SSc patients and 15 healthy controls matched for age and sex underwent clinical examination, serological analysis, and echocardiographic assessment including Doppler flow imaging to evaluate cardiac function, and 24-hour Holter monitoring an...

  18. Value of cardiac multislice spiral CT for the assessment of degenerative aortic stenosis: comparison with echocardiography

    International Nuclear Information System (INIS)

    Objective: To non-invasively assess the severity of aortic valve stenosis (AS) by the determination of aortic valve calcification (AVC) using multislice spiral computed tomography (MSCT). Materials and Methods: Forty-one consecutive patients (17 male, 24 female, mean age 71.0±7.9 years) with a history of AS and an aortic valve area ≤2 cm2 underwent retrospectively ECG-gated 4-slice MSCT and echocardiography. The AVCs were quantitatively assessed using the score described by Agatston as well as by calculating the calcium mass. The echocardiographically determined aortic valve area (AVA) and the severity of AS according to the ACC/AHA guidelines were compared to the degree of a aortic valve calcifications. Pearson's correlation coefficient, cut-off values, kappa test and F-test with post hoc Boneferroni t-tests were calculated. Results: Calcium scores were significantly higher in patients with severe AS, when compared to mild or moderate AS (p<0.001). In patients suffering from severe AS, the mean Agatston score was 4125.5±1168.9 (calcium mass 904.1±263.3) while in patients with moderate and mild AS the corresponding values were 1596.3±987.0 (319.1±208.3) and 785.9±390.1 (149.1±90.2), respectively. Pearson's correlation coefficients were r-=0.75 for the Agatston score and r=-0.72 for the calcium mass. There was a moderate agreement between severity of AS according to the ACC/AHA guidelines and the degree of AS determined from AVC scores with κ=0.6091 and κ=0.6985, respectively. Conclusion: Severe AS may be differentiated from moderate or mild AS using cardiac MSCT. Extensive calcifications of the aortic valve presenting with an Agatston-Score ≥2824 (calcium mass ≥611) indicate a severe AS and should be taken as an indication for further diagnostic workup. (orig.)

  19. Value of cardiac 320-multidetector computed tomography and cardiac magnetic resonance imaging for assessment of myocardial perfusion defects in patients with known chronic ischemic heart disease

    DEFF Research Database (Denmark)

    Qayyum, Abbas Ali; Kühl, Jørgen T; Mathiasen, Anders B;

    2013-01-01

    The challenge for therapies targeting perfusion abnormalities is to identify and evaluate the region of interest. The aim of this study was to compare rest and stress myocardial perfusion measured by cardiac multi-detector computed tomography (MDCT) and cardiac magnetic resonance (CMR) imaging in...

  20. Effects of nimodipine on cerebral blood flow and cerebrospinal fluid pressure after cardiac arrest: correlation with neurologic outcome.

    Science.gov (United States)

    Forsman, M; Aarseth, H P; Nordby, H K; Skulberg, A; Steen, P A

    1989-04-01

    Fifty-one patients were included in a blind randomized study to evaluate whether the Ca-blocker nimodipine could influence cerebral blood flow (CBF) or cerebrospinal fluid pressure (CSFP) during the cerebral hypoperfusion period that follows resuscitation from cardiac arrest and to determine whether changes in CBF correlate with neurologic outcome. CBF measured 1 to 4 hours after arrest with the use of 133Xe intravenous was significantly greater with nimodipine than with placebo (27 +/- 3 versus 13 +/- 1 ml.100 g-1.min-1 at 3 hours), but with no significant difference at 24 hours. There was no clinical evidence of seriously increased CSFP in any patient in either group the first 48 hours. Mean arterial pressure was significantly lower (86 +/- 4 versus 101 +/- 4 mm Hg at 3 hours), and antiarrhythmic drugs were used significantly less frequently in the nimodipine group than in the placebo group. Twelve patients in each group eventually regained consciousness. There was no significant difference in neurologic status between the two groups at any point, and no positive correlation between CBF in the hypoperfusion period and neurologic outcome. PMID:2929976

  1. Cardiac abnormalities in adult patients with polymyositis or dermatomyositis as assessed by non-invasive modatities

    DEFF Research Database (Denmark)

    Christensen, Anne Friesgaard

    2016-01-01

    , factors associated with LVDD were age (P = 0.001), disease duration (P = 0.004), presence of myositis specific/associated autoantibodies (P = 0.05), and high cardiac (99m) Tc-PYP uptake (P = 0.006). In multivariate analysis of the pooled data for patients and HCs, a diagnosis of PM/DM (P < 0.0001) was...... associated with LVDD. Conclusions Patients with PM or DM had an increased prevalence of cardiac abnormalities compared to HCs. LVDD was a common occurrence in PM/DM patients and correlated to disease duration. In addition, the association of LVDD with myositis specific/associated autoantibodies and high...

  2. Assessment of Cardiac Functions in Infants with Cow’s Milk Allergy

    OpenAIRE

    Ece, İbrahim; Demirören, Kaan; Demir, Nihat; Uner, Abdurrahman; Balli, Sevket

    2014-01-01

    Background Cow’s milk allergy is the most common food allergy in children, with rates estimated at 1.9% to 4.9%. Clinical phenotypes of cow’s milk allergy are varied and involve 1 or more target organs, with the main targets being the skin, respiratory system, and gastrointestinal tract. To date, no studies have investigated detailed cardiac function in children with cow’s milk allergy. The current study aimed to investigate cardiac function in infants with cow’s milk allergy. Material/Method...

  3. Assessment of homogeneous non-equilibrium relaxation critical flow model

    International Nuclear Information System (INIS)

    A comprehensive review and assessment of critical flow models were performed previously by Elias and Lellouche (1994). However, a class of critical flow models that is of practical importance was not included in that study. One such model is Homogeneous Non-equilibrium Relaxation Critical Flow Model which belongs to simplified models where one or more non-equilibrium conditions are ignored for modelling ease and computational efficiently. The model assumes equal velocities for the vapor and liquid phases, but considers thermal non-equilibrium between the phases, and is thought to have better characteristics for modeling the subcooled and low quality critical discharge. Unlike other critical flow models currently available in thermal-hydraulic systems codes such as TRAC-PF1/MOD2 and RELAP5/MOD3, this model requires spacial integration of governing equations from the reservoir to the throat assuming that the critical condition exists at the throat. The latest model in this class was developed by Dow-nar-Zapolski et. al, (1996). In this study their Homogeneous Non-equilibrium Relaxation Critical Flow Model was assessed against the full range of critical flow data including the dataset compiled by Ilic (1986), the Marviken CFT (EPRI-NP-2370, 1982), and data with two-phase upstream condition by Anderson (1986). Prediction accuracy, selected parametric effects of upstream fluid conditions, geometry effects are discussed. (author)

  4. Myocardial bridging in a survivor of sudden cardiac near-death: role of intracoronary doppler flow measurements and angiography during dobutamine stress in the clinical evaluation.

    OpenAIRE

    Tio, R.A.; van Gelder, I.C.; Boonstra, P.W.; Crijns, H. J.

    1997-01-01

    Extensive myocardial bridging in the left anterior descending coronary artery was found in a 46 year old survivor of sudden cardiac near-death. Positron emission tomography and dobutamine stress echocardiography revealed ischaemia in the myocardium distal to the bridging. Spasm was excluded as cause of the ischaemia by intracoronary infusion of acetylcholine. Further evaluation of the haemodynamic importance of the bridging using intracoronary Doppler flow velocity measurements revealed an ab...

  5. Flow-weighted MRI of the lungs with the ECG-gated half-fourier FSE technique. Evaluation of the effect of the cardiac cycle

    International Nuclear Information System (INIS)

    We investigated temporal MR signal changes in the peripheral lung and proximal pulmonary vessels during the entire cardiac cycle in order to evaluate the characteristics of the diastolic-systolic subtraction method in the lung. In eight healthy volunteers free of lung diseases, changes in the MR signal during one breath-hold were investigated with the multiple electrocardiogram (ECG)-triggered half-Fourier single-shot fast-spin echo (SS-FSE) technique. The signal intensity-time course curve in the lung showed that biphasic signals decreased 20% to 47% at systole and 5% to 33% at mid-diastole, measured against the maximum signals at late diastole. This signal decrease in the peripheral lung was correlated to that in the proximal pulmonary vessels during an entire cardiac cycle (r=0.667 to 1.000). The best visualization of the lung was obtained at late diastole, when the intra-vascular flow in the lung was expected to be stagnant. Compared with the late diastolic SS-FSE images, the late diastolic-systolic subtracted SS-FSE images improved the signal-to-noise ratio in the lung as well as the signal-intensity ratio of the peripheral lung to surrounding tissues. Although the flow-induced signal dephasing in the lung was completely unavoidable and its amount was unpredictable even at late diastole, the diastolic-systolic subtracted SS-FSE images showed the relative differences in flow alteration during the cardiac cycle between the images at diastole and those at systole. The main characteristic of diastolic-systolic subtracted SS-FSE was the enhancement of visibility of cardiac-dependent signal changes in the lung due to the alteration in pulsatile flow. (author)

  6. Physiological changes in human cardiac sympathetic innervation and activity assessed by 123I-metaiodobenzylguanidine (MIBG) imaging

    International Nuclear Information System (INIS)

    Physiologic changes in the human sympathetic nervous system (SNS) may be associated with cardiovascular diseases, so the present study assessed the age and gender differences in global cardiac SNS in normal subjects. The 163 subjects (74 men, 89 women; age range 40-89 years) whose coronary arteriogram was normal, and who had no other cardiac or neurohormonal diseases, and no medication affecting the autonomic nervous system were included. All study subjects underwent metaiodobenzylguanidine imaging. Both initial and delayed heart-to-mediastinum (H/M) ratios had a significant gender difference and showed a progressive decrease with aging. In addition, the initial H/M ratio had a significant positive correlation with the delayed H/M ratio (r=0.89, P<0.0001). Females (50-59 years) demonstrated significantly higher delayed H/M ratio than males of the same age. After the age of 60, the delayed H/M ratio in females progressively decreased with aging, similar to males. As for the washout rate, both genders had a significantly progressive increase with aging. In addition, there was a significant decrease in the delayed H/M ratio in 10 females with surgical menopause compared with 15 age-matched females without surgical menopause. Cardiac SNS appears to be regulated by various physiological factors. (author)

  7. Left Ventricular Stroke Volume Quantification by Contrast Echocardiography – Comparison of Linear and Flow-Based Methods to Cardiac Magnetic Resonance

    Science.gov (United States)

    Dele-Michael, Abiola O.; Fujikura, Kana; Devereux, Richard B; Islam, Fahmida; Hriljac, Ingrid; Wilson, Sean R.; Lin, Fay; Weinsaft, Jonathan W.

    2014-01-01

    Background Echocardiography (echo) quantified LV stroke volume (SV) is widely used to assess systolic performance after acute myocardial infarction (AMI). This study compared two common echo approaches – predicated on flow (Doppler) and linear chamber dimensions (Teichholz) – to volumetric SV and global infarct parameters quantified by cardiac magnetic resonance (CMR). Methods Multimodality imaging was performed as part of a post-AMI registry. For echo, SV was measured by Doppler and Teichholz methods. Cine-CMR was used for volumetric SV and LVEF quantification, and delayed-enhancement CMR for infarct size. Results 142 patients underwent same-day echo and CMR. On echo, mean SV by Teichholz (78±17ml) was slightly higher than Doppler (75±16ml; Δ=3±13ml, p=0.02). Compared to SV on CMR (78±18ml), mean difference by Teichholz (Δ=−0.2±14; p=0.89) was slightly smaller than Doppler (Δ−3±14; p=0.02) but limits of agreement were similar between CMR and echo methods (Teichholz: −28, 27 ml, Doppler: −31, 24ml). For Teichholz, differences with CMR SV were greatest among patients with anteroseptal or lateral wall hypokinesis (p<0.05). For Doppler, differences were associated with aortic valve abnormalities or root dilation (p=0.01). SV by both echo methods decreased stepwise in relation to global LV injury as assessed by CMR-quantified LVEF and infarct size (p<0.01). Conclusions Teichholz and Doppler calculated SV yield similar magnitude of agreement with CMR. Teichholz differences with CMR increase with septal or lateral wall contractile dysfunction, whereas Doppler yields increased offsets in patients with aortic remodeling. PMID:23488864

  8. MIBG scintigraphic assessment of cardiac adrenergic activity in response to altitude hypoxia

    International Nuclear Information System (INIS)

    High altitude hypoxia induces a decrease in the cardiac chronotropic function at maximal exercise or in response to isoproterenol infusion, suggesting an alteration in the cardiac sympathetic activation. Iodine-123 metaiodobenzylguanidine [(123I]MIBG) was used to map scintigraphically the cardiac sympathetic neuronal function in six male subjects (aged 32 ± 7 yr) after an exposure to high altitude that created hypoxic conditions. Results obtained just after return to sea level (RSL) were compared with the normal values obtained after 2 or 3 mo of normoxia (N). A static image was created as the sum of the 16-EKG gated images recorded for 10 min in the anterior view of the chest at 20, 60, 120, and 240 min after injection. Regions of interest were located over the heart (H), lungs (L), and mediastinum (M) regions. There was a significant decrease in the H/M and the L/M ratios in RSL compared to N condition. Plasma norepinephrine concentration was elevated during the stay at altitude but not significantly different in RSL compared to N. In conclusion, cardiac [123I]MIBG uptake is reduced after an exposure to altitude hypoxia, supporting the hypothesis of an hypoxia-induced reduction of adrenergic neurotransmitter reserve in the myocardium. Furthermore, the observed significant decrease in pulmonary MIBG uptake suggests an alteration of endothelial cell function after exposure to chronic hypoxia

  9. Electrocardiographically gated 11C-hydroxyephedrine PET for the simultaneous assessment of cardiac sympathetic and contractile functions

    International Nuclear Information System (INIS)

    Application of the electrocardiographically (ECG) gated positron emission tomography (PET) technique with 11C-hydroxyephedrine (HED) would allow the simultaneous assessment of cardiac sympathetic and contractile functions. However, there are uncertainties regarding the diagnostic accuracy of left ventricular (LV) volume measurements using ECG-gated HED-PET. The purpose of this study was to clarify the minimal requirement of count statistics to measure LV volumes with ECG-gated HED-PET and to investigate the reliability of the measurements. Five healthy volunteers and 11 patients with heart failure underwent a 40-min list-mode PET scan after an injection of HED (197 ± 35 MBq). The list-mode data were histogrammed into multiple sets of acquisition periods at 0.5, 1.0, 2.0, 4.0, 6.0, 8.0, 12.0 Mcount/bin and reconstructed into corresponding gated images using an iterative algorithm. The LV end-diastolic volume (LVEDV), the LV end-systolic volume (LVESV), and the LV ejection fraction (LVEF) were calculated in each acquisition period. These values were compared with those obtained by cardiac magnetic resonance imaging (MRI). Possible effects of HED retention on the accuracy of the volume measurements were investigated. Collecting less than 4.0 Mcount/bin resulted in noisy cardiac images. The lower counts resulted in underestimation in the volume measurements. Reasonably accurate volume measurements required equal to or greater than 6.0 Mcount/bin. This corresponded to 7.0 ± 1.9 min (range, 4.0-10.3 min) for the acquisition period. Volumetric results using the 6.0 Mcount/bin data highly correlated with cardiac MRI (LVEDV: r=0.85, p < 0.0001; LVESV: r=0.89, p < 0.0001; LVEF: r=0.77, p < 0.01). The HED retention did not affect the volumetric results compared to the MRI volumetry. The volumetric accuracy with ECG-gated HED-PET was affected by the count statistics rather than the HED retention. LV volume measurements were feasible with 10-min acquisition period for most of

  10. Effects of short-term carvedilol on the cardiac sympathetic activity assessed by {sup 123}I-MIBG scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, Sandra Marina Ribeiro de; Mesquita, Evandro Tinoco; Freire, Fabiano de Lima; Ribeiro, Mario Luiz; Nobrega, Antonio Claudio Lucas da; Mesquita, Claudio Tinoco, E-mail: sandramarina@cardiol.b [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil); Azevedo, Jader Cunha; Barbirato, Gustavo Borges; Coimbra, Alexandro [Hospital Pro-Cardiaco, Rio de Janeiro, RJ (Brazil); Dohmann, Hans Fernando da Rocha [Centro de Ensino e Pesquisa do Pro-Cardiaco (PROCEP), Rio de Janeiro, RJ (Brazil)

    2010-03-15

    Background: autonomic alterations in heart failure are associated with an increase in morbimortality. Several noninvasive methods have been employed to evaluate the sympathetic function, including the Meta-Iodobenzylguanidine ({sup 123}I-MIBG) scintigraphy imaging of the heart. Objective: to evaluate the cardiac sympathetic activity through {sup 123}I-MIBG scintigraphy, before and after three months of carvedilol therapy in patients with heart failure and left ventricular ejection fraction (LVEF) < 45%. Patients and methods: sixteen patients, aged 56.3 +- 12.6 years (11 males), with a mean LVEF of 28% +- 8% and no previous use of beta-blockers were recruited for the study. Images of the heart innervation were acquired with {sup 123}I-MIBG, and the serum levels of catecholamines (epinephrine, dopamine and norepinephrine) were measured; the radioisotope ventriculography (RIV) was performed before and after a three-month therapy with carvedilol. Results: patients' functional class showed improvement: before the treatment, 50% of the patients were FC II and 50% were FC III. After 3 months, 7 patients were FC I (43.8%) and 9 were FC II (56.2%), (rho = 0.0001). The mean LVEF assessed by RIV increased from 29% to 33% (rho = 0.017). There was no significant variation in cardiac adrenergic activity assessed by {sup 123}I-MIBG (early and late resting images and washout rate). No significant variation was observed regarding the measurement of catecholamines. Conclusion: the short-term treatment with carvedilol promoted the clinical and LVEF improvement. However, this was not associated to an improvement in the cardiac adrenergic activity, assessed by {sup 123}I-MIBG scintigraphy, as well as the measurement of circulating catecholamines. (author)

  11. Assessment of Myocardial Infarction by Cardiac Magnetic Resonance Imaging and Long-Term Mortality

    Directory of Open Access Journals (Sweden)

    João Luiz Fernandes Petriz

    2015-02-01

    Full Text Available Background: Cardiac magnetic resonance imaging provides detailed anatomical information on infarction. However, few studies have investigated the association of these data with mortality after acute myocardial infarction. Objective: To study the association between data regarding infarct size and anatomy, as obtained from cardiac magnetic resonance imaging after acute myocardial infarction, and long-term mortality. Methods: A total of 1959 reports of “infarct size” were identified in 7119 cardiac magnetic resonance imaging studies, of which 420 had clinical and laboratory confirmation of previous myocardial infarction. The variables studied were the classic risk factors – left ventricular ejection fraction, categorized ventricular function, and location of acute myocardial infarction. Infarct size and acute myocardial infarction extent and transmurality were analyzed alone and together, using the variable named “MET-AMI”. The statistical analysis was carried out using the elastic net regularization, with the Cox model and survival trees. Results: The mean age was 62.3 ± 12 years, and 77.3% were males. During the mean follow-up of 6.4 ± 2.9 years, there were 76 deaths (18.1%. Serum creatinine, diabetes mellitus and previous myocardial infarction were independently associated with mortality. Age was the main explanatory factor. The cardiac magnetic resonance imaging variables independently associated with mortality were transmurality of acute myocardial infarction (p = 0.047, ventricular dysfunction (p = 0.0005 and infarcted size (p = 0.0005; the latter was the main explanatory variable for ischemic heart disease death. The MET-AMI variable was the most strongly associated with risk of ischemic heart disease death (HR: 16.04; 95%CI: 2.64-97.5; p = 0.003. Conclusion: The anatomical data of infarction, obtained from cardiac magnetic resonance imaging after acute myocardial infarction, were independently associated with long

  12. Assessment of Myocardial Infarction by Cardiac Magnetic Resonance Imaging and Long-Term Mortality

    Energy Technology Data Exchange (ETDEWEB)

    Petriz, João Luiz Fernandes, E-mail: jlpetriz@cardiol.br [Universidade Federal do Rio de Janeiro (UFRJ) / Instituto do Coração Edson Saad - Programa de Pós Graduação em Medicina (Cardiologia), Rio de Janeiro, RJ (Brazil); Hospital Barra D’Or, Rio de Janeiro, RJ (Brazil); Instituto D’Or de Pesquisa e Ensino, Rio de Janeiro, RJ (Brazil); Gomes, Bruno Ferraz de Oliveira; Rua, Braulio Santos [Hospital Barra D’Or, Rio de Janeiro, RJ (Brazil); Azevedo, Clério Francisco [Instituto D’Or de Pesquisa e Ensino, Rio de Janeiro, RJ (Brazil); Hadlich, Marcelo Souza [Universidade Federal do Rio de Janeiro (UFRJ) / Instituto do Coração Edson Saad - Programa de Pós Graduação em Medicina (Cardiologia), Rio de Janeiro, RJ (Brazil); Instituto D’Or de Pesquisa e Ensino, Rio de Janeiro, RJ (Brazil); Mussi, Henrique Thadeu Periard [Universidade Federal do Rio de Janeiro (UFRJ) / Instituto do Coração Edson Saad - Programa de Pós Graduação em Medicina (Cardiologia), Rio de Janeiro, RJ (Brazil); Hospital Barra D’Or, Rio de Janeiro, RJ (Brazil); Taets, Gunnar de Cunto [Instituto D’Or de Pesquisa e Ensino, Rio de Janeiro, RJ (Brazil); Nascimento, Emília Matos do; Pereira, Basílio de Bragança; Silva, Nelson Albuquerque de Souza e [Universidade Federal do Rio de Janeiro (UFRJ) / Instituto do Coração Edson Saad - Programa de Pós Graduação em Medicina (Cardiologia), Rio de Janeiro, RJ (Brazil)

    2015-02-15

    Cardiac magnetic resonance imaging provides detailed anatomical information on infarction. However, few studies have investigated the association of these data with mortality after acute myocardial infarction. To study the association between data regarding infarct size and anatomy, as obtained from cardiac magnetic resonance imaging after acute myocardial infarction, and long-term mortality. A total of 1959 reports of “infarct size” were identified in 7119 cardiac magnetic resonance imaging studies, of which 420 had clinical and laboratory confirmation of previous myocardial infarction. The variables studied were the classic risk factors – left ventricular ejection fraction, categorized ventricular function, and location of acute myocardial infarction. Infarct size and acute myocardial infarction extent and transmurality were analyzed alone and together, using the variable named “MET-AMI”. The statistical analysis was carried out using the elastic net regularization, with the Cox model and survival trees. The mean age was 62.3 ± 12 years, and 77.3% were males. During the mean follow-up of 6.4 ± 2.9 years, there were 76 deaths (18.1%). Serum creatinine, diabetes mellitus and previous myocardial infarction were independently associated with mortality. Age was the main explanatory factor. The cardiac magnetic resonance imaging variables independently associated with mortality were transmurality of acute myocardial infarction (p = 0.047), ventricular dysfunction (p = 0.0005) and infarcted size (p = 0.0005); the latter was the main explanatory variable for ischemic heart disease death. The MET-AMI variable was the most strongly associated with risk of ischemic heart disease death (HR: 16.04; 95%CI: 2.64-97.5; p = 0.003). The anatomical data of infarction, obtained from cardiac magnetic resonance imaging after acute myocardial infarction, were independently associated with long-term mortality, especially for ischemic heart disease death.

  13. Quantitative assessment of left ventricular function with dual-source CT in comparison to cardiac magnetic resonance imaging: initial findings

    International Nuclear Information System (INIS)

    Cardiac magnetic resonance imaging and echocardiography are currently regarded as standard modalities for the quantification of left ventricular volumes and ejection fraction. With the recent introduction of dual-source computedtomography (DSCT), the increased temporal resolution of 83 ms should also improve the assessment of cardiac function in CT. The aim of this study was to evaluate the accuracy of DSCT in the assessment of left ventricular functional parameters with cardiac magnetic resonance imaging (MRI) as standard of reference. Fifteen patients (two female, 13 male; mean age 50.8 ± 19.2 years) underwent CT and MRI examinations on a DSCT (Somatom Definition; Siemens Medical Solutions, Forchheim, Germany) and a 3.0-Tesla MR scanner (Magnetom Trio; Siemens Medical Solutions), respectively. Multiphase axial CT images were analysed with a semiautomatic region growing algorithms (Syngo Circulation; Siemens Medical Solutions) by two independent blinded observers. In MRI, dynamic cine loops of short axis slices were evaluated with semiautomatic contour detection software (ARGUS; Siemens Medical Solutions) independently by two readers. End-systolic volume (ESV), end-diastolic volume (EDV), ejection fraction (EF) and stroke volume (SV) were determined for both modalities, and correlation coefficient, systematic error, limits of agreement and inter-observer variability were assessed. In DSCT, EDV and ESV were 135.8 ± 41.9 ml and 54.9 ± 29.6 ml, respectively, compared with 132.1 ± 40.8 ml EDV and 57.6 ± 27.3 ml ESV in MRI. Thus, EDV was overestimated by 3.7 ml (limits of agreement -46.1/+53.6), while ESV was underestimated by 2.6 ml (-36.6/+31.4). Mean EF was 61.6 ± 12.4% in DSCT and 57.9 ± 9.0% in MRI, resulting in an overestimation of EF by 3.8% with limits of agreement at -14.7 and +22.2%. Rank correlation rho values were 0.81 for EDV (P = 0.0024), 0.79 for ESV (P 0.0031) and 0.64 for EF (P = 0.0168). The kappa value of inter-observer variability were

  14. Flow and Noise Control: Review and Assessment of Future Directions

    Science.gov (United States)

    Thomas, Russell H.; Choudhari, Meelan M.; Joslin, Ronald D.

    2002-01-01

    Technologies for developing radically new aerovehicles that would combine quantum leaps in cost, safety, and performance benefits with environmental friendliness have appeared on the horizon. This report provides both an assessment of the current state-of-the-art in flow and noise control and a vision for the potential gains to be made, in terms of performance benefit for civil and military aircraft and a unique potential for noise reduction, via future advances in flow and noise technologies. This report outlines specific areas of research that will enable the breakthroughs necessary to bring this vision to reality. Recent developments in many topics within flow and noise control are reviewed. The flow control overview provides succinct summaries of various approaches for drag reduction and improved maneuvering. Both exterior and interior noise problems are examined, including dominant noise sources, physics of noise generation and propagation, and both established and proposed concepts for noise reduction. Synergy between flow and noise control is a focus and, more broadly, the need to pursue research in a more concurrent approach involving multiple disciplines. Also discussed are emerging technologies such as nanotechnology that may have a significant impact on the progress of flow and noise control.

  15. Environmental flow assessments in estuaries related to preference of phytoplankton

    Science.gov (United States)

    Yang, Z. F.; Sun, T.; Zhao, R.

    2014-05-01

    An approach to assess estuarine environmental flow based on phytoplankton preference, including the complex relationships between hydrological modifications and ecosystem biomass, was developed in this study. We initially established a relationship between biomass requirements for primary and higher nutritional level organisms based on the ecosystem nutritional energy flow principles. Subsequently, diagnostic pigments were employed to represent phytoplankton community biomass, which indicated competition between two groups of phytoplankton in the biochemistry process. Considering empirical relationships between diagnostic pigments and critical environmental factors, biomass responses to river discharge were established by simulating distributions of critical environmental factors under action of river discharges and tide currents. Consequently, environmental flows were recommended for different fish biomass requirements. We used the Yellow River estuary as a case study; and May and June were identified as critical months for maintaining environmental flow. Temporal variation in natural river flow dynamics, which was used as a proxy for environmental flow, should be carefully examined in artificial hydrological regulation strategies, particularly during high-amplitude flood pulses, which might result in negative effects on phytoplankton groups, and subsequently higher aquatic species biomass.

  16. Parameterization of real-time 3D speckle tracking framework for cardiac strain assessment.

    Science.gov (United States)

    Lorsakul, Auranuch; Duan, Qi; Po, Ming Jack; Angelini, Elsa; Homma, Shunichi; Laine, Andrew F

    2011-01-01

    Cross-correlation based 3D speckle tracking algorithm can be used to automatically track myocardial motion on three dimensional real-time (RT3D) echocardiography. The goal of this study was to experimentally investigate the effects of different parameters associated with such algorithm to ensure accurate cardiac strain measurements. The investigation was performed on 10 chronic obstructive pulmonary disease RT3DE cardiac ultrasound images. The following two parameters were investigated: 1) the gradient threshold of the anisotropic diffusion pre-filtering and 2) the window size of the cross correlation template matching in the speckle tracking. Results suggest that the optimal gradient threshold of the anisotropic filter depends on the average gradient of the background speckle noise, and that an optimal pair of template size and search window size can be identified determines the cross-correlation level and computational cost. PMID:22254887

  17. [Assessment of risk of sudden cardiac death in patients with hypertrophic cardiomyopathy].

    Science.gov (United States)

    Attanasio, Philipp; Blaschke, Florian; Pieske, Burkert; Tschöpe, Carsten; Haverkamp, Wilhelm

    2016-07-01

    Hypertrophic cardiomyopathy (HCM) is a hereditary disease characterized by left ventricular hypertrophy with or without concomitant outflow tract obstruction. Identification of patients with HCM who are at high risk of sudden cardiac death (SCD) is crucial as those patients are likely to benefit from an implantable cardioverter defibrillator (ICD). Based on the HCM Risk-SCD study published in 2013, that included 3675 HCM patients with 24 313 years of follow up, a new clinical risk prediction model for sudden cardiac death was developed. This model was included in the recently released 2014 ESC guidelines. This review summarizes the changes in the prediction model and the resulting recommendations and discusses potential risks and limitations of the new score. PMID:27404936

  18. Assessment of cardiac outcome in pancreas kidney transplant recipients using 99mTc-MIBI myocardial perfusion scintigraphy

    International Nuclear Information System (INIS)

    Full text: Simultaneous pancreas-kidney transplantation (SPK) in diabetic patients (patients) 99mTc-MIBI myocardial perfusion scintigraphy (MPI) in predicting cardiac outcome post SPK. One hundred and forty patients underwent SPK at our institution over a 15-year period. Sixty-six subjects were excluded because of incomplete follow-up (n=54) or death from non-cardiac causes (n=12). Seventy-four patients (44 men, 30 women) with age 44.3+/-7.4 yrs (range: 31-62yrs) were followed for up to 14 yrs post SPK. The mean interval between SPK and MPI was 48.1+/-37.1 months (median: 37.5, range: 6-132 months). MPI was performed using a standard two-day protocol with Adenosine or Dipyridamole and a dual-head gamma camera using 900 configuration, attenuation and scatter correction and resolution recovery. Images were reported by at least one experienced observer using standard software. MPI were classified as normal (n=33), infarct (n=4), small (n=32) or large (n=2) areas of impaired coronary flow reserve (CFR) or a combination of infarct and impaired CFR (n=3). Cardiac events were considered if infarct, angina, death or coronary revascularisation occurred. Two patients underwent coronary artery bypass surgery five yrs post SPK (both two yrs post MPI) and one patient developed angina six yrs post SPK (three yrs post MPI). In these patients, MPI showed only small areas of impaired CFR. The negative and positive predictive values for MPI were 100 and 9%, respectively. In summary, MPI has excellent NPV post SPK. The PPV is poor, suggesting that myocardial perfusion defects correlate only weakly with overall atherosclerotic risk profile post SPK. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

  19. Preoperative cardiac risk management

    OpenAIRE

    Vidaković Radosav; Poldermans Don; Nešković Aleksandar N.

    2011-01-01

    Approximately 100 million people undergo noncardiac surgery annually worldwide. It is estimated that around 3% of patients undergoing noncardiac surgery experience a major adverse cardiac event. Although cardiac events, like myocardial infarction, are major cause of perioperative morbidity or mortality, its true incidence is difficult to assess. The risk of perioperative cardiac complications depends mainly on two conditions: 1) identified risk factors, and 2) the type of the surgical p...

  20. Myocardial inflammation after binge drinking assessed by cardiac magnetic resonance imaging

    OpenAIRE

    Aiche, Sascha

    2011-01-01

    Background: Chronic alcohol abuse leads to inflammatory changes in myocardium. The aim of this study was to determine acute effects of excessive consumption of alcohol – binge drinking – and hangover on the heart especially in myocardium. We assumed that binge drinking leads to detectable changes in myocardium. Methods: Cardiac-MRI (CMR) was the diagnostic method. Evaluated parameters were T2-Ratio, relative enhancement, late enhancement and left ventricular function. Additionally humoral...

  1. Clinical validation of a new thermodilution system for the assessment of cardiac output and volumetric parameters

    OpenAIRE

    Kiefer, Nicholas; Hofer, Christoph K; Marx, Gernot; Geisen, Martin; Giraud, Raphaël; Siegenthaler, Nils; Hoeft, Andreas; Bendjelid, Karim; Rex, Steffen

    2012-01-01

    ABSTRACT: INTRODUCTION: Transpulmonary thermodilution is used to measure cardiac output (CO), global end-diastolic volume (GEDV) and extravascular lung water (EVLW). A system has been introduced (VolumeView/EV1000™ system, Edwards Lifesciences, Irvine CA, USA) that employs a novel algorithm for the mathematical analysis of the thermodilution curve. Our aim was to evaluate the agreement of this method with the established PiCCO™ method (Pulsion Medical Systems SE, Munich, Germany, clinicaltria...

  2. Age-related normal structural and functional ventricular values in cardiac function assessed by magnetic resonance

    International Nuclear Information System (INIS)

    The heart is subject to structural and functional changes with advancing age. However, the magnitude of cardiac age-dependent transformation has not been conclusively elucidated. This retrospective cardiac magnetic resonance (CMR) study included 183 subjects with normal structural and functional ventricular values. End systolic volume (ESV), end diastolic volume (EDV), and ejection fraction (EF) were obtained from the left and the right ventricle in breath-hold cine CMR. Patients were classified into four age groups (20–29, 30–49, 50–69, and ≥70 years) and cardiac measurements were compared using Pearson’s rank correlation over the four different groups. With advanced age a slight but significant decrease in ESV (r=−0.41 for both ventricles, P<0.001) and EDV (r=−0.39 for left ventricle, r=−0.35 for right ventricle, P<0.001) were observed associated with a significant increase in left (r=0.28, P<0.001) and right (r=0.27, P<0.01) ventricular EF reaching a maximal increase in EF of +8.4% (P<0.001) for the left and +6.1% (P<0.01) for the right ventricle in the oldest compared to the youngest patient group. Left ventricular myocardial mass significantly decreased over the four different age groups (P<0.05). The aging process is associated with significant changes in left and right ventricular EF, ESV and EDV in subjects with no cardiac functional and structural abnormalities. These findings underline the importance of using age adapted values as standard of reference when evaluating CMR studies

  3. Assessment of endothelial function by brachial artery flow mediated dilatation in microvascular disease

    Directory of Open Access Journals (Sweden)

    Naidu Otikunta

    2011-12-01

    Full Text Available Abstract Background Cardiac syndrome X is an important therapeutic and diagnostic challenge to physician. Study of Csx patients may help to understand the pathophysiology of coronary microcirculation and to gain an insight on the management of these group patients. Methods We measured the flow mediated dilation of the brachial artery both endothelium dependent and independent vasodilatation by high resolution ultrasound in 30 cardiac syndrome X patients and matched with 30 healthy control subjects. Results Significantly decreased flow mediated dilatation was observed in patients when compared to control (9.42 ± 7.20 vs 21.11 ± 9.16 p 11.11(p Conclusions The study suggests impairment of endothelial function in cardiac syndrome X patients. Increased Systolic blood pressure and body mass index may increase the risk of impairment of endothelial function in this group of patients.

  4. New York Heart Association class assessment by cardiologists and outpatients with congenital cardiac disease: a head-to-head comparison of three patient-based versions

    NARCIS (Netherlands)

    D. Schoormans; Y.L. Mager; F.J. Oort; M.A.G. Sprangers; B.J.M. Mulder

    2012-01-01

    Background: The objective of this study was to compare three patient-based New York Heart Association assessments with cardiologist assessments in outpatients with congenital cardiac disease. Methods: Consecutive adult outpatients completed three questionnaires in a random order: a patient-based tra

  5. Role of Nuclear Medicine in the cardiac resinchronization therapy

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-10-15

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

  6. Role of Nuclear Medicine in the cardiac resinchronization therapy

    International Nuclear Information System (INIS)

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

  7. CRITICAL ASSESSMENT OF AUTOMATED FLOW CYTOMETRY DATA ANALYSIS TECHNIQUES

    Science.gov (United States)

    Aghaeepour, Nima; Finak, Greg; Hoos, Holger; Mosmann, Tim R.; Gottardo, Raphael; Brinkman, Ryan; Scheuermann, Richard H.

    2013-01-01

    Traditional methods for flow cytometry (FCM) data processing rely on subjective manual gating. Recently, several groups have developed computational methods for identifying cell populations in multidimensional FCM data. The Flow Cytometry: Critical Assessment of Population Identification Methods (FlowCAP) challenges were established to compare the performance of these methods on two tasks – mammalian cell population identification to determine if automated algorithms can reproduce expert manual gating, and sample classification to determine if analysis pipelines can identify characteristics that correlate with external variables (e.g., clinical outcome). This analysis presents the results of the first of these challenges. Several methods performed well compared to manual gating or external variables using statistical performance measures, suggesting that automated methods have reached a sufficient level of maturity and accuracy for reliable use in FCM data analysis. PMID:23396282

  8. Assessment for hydrodynamic masses of HANARO flow tubes

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jeong Soo; Cho, Yeong Garp; Kim, Doo Kie; Woo, Jong Sug; Park, Jin Ho

    2000-06-01

    The effect of hydrodynamic masses is investigated in dynamic characteristics and seismic response analyses of the submerged HANARO hexagonal flow tubes. Consistent hydrodynamic masses of the surrounding water are evaluated by the prepared program using the finite element method, in which arbitrary cross-sections of submerged structures and boundary conditions of the surrounding fluid can be considered. Also lumped hydrodynamic masses are calculated using simple formula applied to hexagonal flow tubes in the infinite fluid. Modal analyses and seismic response spectrum analyses were performed using hydrodynamic masses obtained by the finite element method and the simple formula. The results of modal analysis were verified by comparing the results measured from modal tests. And the displacement results of the seismic response spectrum analysis were assessed by comparing the consistent and the lumped hydrodynamic masses obtained by various methods. Finally practical criteria based on parametric studies are proposed as the lumped hydrodynamic masses for HANARO flow tubes.

  9. Assessment for hydrodynamic masses of HANARO flow tubes

    International Nuclear Information System (INIS)

    The effect of hydrodynamic masses is investigated in dynamic characteristics and seismic response analyses of the submerged HANARO hexagonal flow tubes. Consistent hydrodynamic masses of the surrounding water are evaluated by the prepared program using the finite element method, in which arbitrary cross-sections of submerged structures and boundary conditions of the surrounding fluid can be considered. Also lumped hydrodynamic masses are calculated using simple formula applied to hexagonal flow tubes in the infinite fluid. Modal analyses and seismic response spectrum analyses were performed using hydrodynamic masses obtained by the finite element method and the simple formula. The results of modal analysis were verified by comparing the results measured from modal tests. And the displacement results of the seismic response spectrum analysis were assessed by comparing the consistent and the lumped hydrodynamic masses obtained by various methods. Finally practical criteria based on parametric studies are proposed as the lumped hydrodynamic masses for HANARO flow tubes

  10. Impedance measurement to assess epicardial fat prior to RF intraoperative cardiac ablation: a feasibility study using a computer model

    International Nuclear Information System (INIS)

    Radiofrequency (RF) cardiac ablation is used to treat certain types of arrhythmias. In the epicardial approach, efficacy of RF ablation is uncertain due to the presence of epicardial adipose tissue interposed between the ablation electrode and the atrial wall. We planned a feasibility study based on a theoretical model in order to assess a new technique to estimate the quantity of fat by conducting bioimpedance measurements using a multi-electrode probe. The finite element method was used to solve the electrical problem. The results showed that the measured impedance profile coincided approximately with the epicardial fat profile measured under the probe electrodes and also that the thicker the epicardial fat, the higher the impedance values. When the lateral fat width was less than 4.5 mm, the impedance values altered, suggesting that measurements should always be conducted over a sizeable fat layer. We concluded that impedance measurement could be a practical method of assessing epicardial fat prior to RF intraoperative cardiac ablation, i.e. 'to map' the amount of adipose tissue under the probe. (note)

  11. Assessment of Equine Autoimmune Thrombocytopenia (EAT by flow cytometry

    Directory of Open Access Journals (Sweden)

    Schwarzwald Colin

    2001-04-01

    Full Text Available Abstract Rationale Thrombocytopenia is a platelet associated process that occurs in human and animals as result of i decreased production; ii increased utilization; iii increased destruction coupled to the presence of antibodies, within a process know as immune-mediated thrombocytopenia (IMT; or iv platelet sequestration. Thus, the differentiation of the origin of IMT and the development of reliable diagnostic approaches and methodologies are important in the clarification of IMT pathogenesis. Therefore, there is a growing need in the field for easy to perform assays for assessing platelet morphological characteristics paired with detection of platelet-bound IgG. Objectives This study is aimed to develop and characterize a single color flow cytometric assay for detection of platelet-bound IgG in horses, in combination with flow cytometric assessment of platelet morphological characteristics. Findings The FSC and SSC evaluation of the platelets obtained from the thrombocytopenic animals shows several distinctive features in comparison to the flow cytometric profile of platelets from healthy animals. The thrombocytopenic animals displayed i increased number of platelets with high FSC and high SSC, ii a significant number of those gigantic platelets had strong fluorescent signal (IgG bound, iii very small platelets or platelet derived microparticles were found significantly enhanced in one of the thrombocytopenic horses, iv significant numbers of these microplatelet/microparticles/platelet-fragments still carry very high fluorescence. Conclusions This study describes the development and characterization of an easy to perform, inexpensive, and noninvasive single color flow cytometric assay for detection of platelet-bound IgG, in combination with flow cytometric assessment of platelet morphological characteristics in horses.

  12. ULTRASOUND ASSESSMENT OF FLOW-MEDIATED DILATION: A TUTORIAL

    OpenAIRE

    Harris, Ryan A.; Nishiyama, Steven K.; Wray, D. Walter; Richardson, Russell S.

    2010-01-01

    Developed in 1992, the flow-mediated dilation test is now the most commonly utilized non-invasive assessment of vascular endothelial function in humans. Since its inception, scientists have refined their understanding of the physiology, analysis, and interpretation of this measurement. Recently, a significant growth of knowledge has added to our understanding and implementation of this clinically relevant research methodology. Therefore, this tutorial provides timely insight into recent advan...

  13. Flow cytometric assessment of viability of lactic acid bacteria

    OpenAIRE

    Bunthof, C.J.; Bloemen, K.; Breeuwer, P.; Rombouts, F. M.; Abee, T

    2001-01-01

    The viability of lactic acid bacteria is crucial for their applications as dairy starters and as probiotics. We investigated the usefulness of flow cytometry (FCM) for viability assessment of lactic acid bacteria. The esterase substrate carboxyfluorescein diacetate (cFDA) and the dye exclusion DNA binding probes propidium iodide (PI) and TOTO-1 were tested for live/dead discrimination using a Lactococcus, a Streptococcus, three Lactobacillus, two Leuconostoc, an Enterococcus, and a Pediococcu...

  14. Limitations of early serum creatinine variations for the assessment of kidney injury in neonates and infants with cardiac surgery.

    Directory of Open Access Journals (Sweden)

    Mirela Bojan

    Full Text Available BACKGROUND: Changes in kidney function, as assessed by early and even small variations in serum creatinine (ΔsCr, affect survival in adults following cardiac surgery but such associations have not been reported in infants. This raises the question of the adequate assessment of kidney function by early ΔsCr in infants undergoing cardiac surgery. METHODOLOGY: The ability of ΔsCr within 2 days of surgery to assess the severity of kidney injury, accounted for by the risk of 30-day mortality, was explored retrospectively in 1019 consecutive neonates and infants. Patients aged ≤ 10 days were analyzed separately because of the physiological improvement in glomerular filtration early after birth. The Kml algorithm, an implementation of k-means for longitudinal data, was used to describe creatinine kinetics, and the receiver operating characteristic and the reclassification methodology to assess discrimination and the predictive ability of the risk of death. RESULTS: Three clusters of ΔsCr were identified: in 50% of all patients creatinine decreased, in 41.4% it increased slightly, and in 8.6% it rose abruptly. Mortality rates were not significantly different between the first and second clusters, 1.6% [0.0-4.1] vs 5.9% [1.9-10.9], respectively, in patients aged ≤ 10 days, and 1.6% [0.5-3.0] vs 3.8% [1.9-6.0] in older ones. Mortality rates were significantly higher when creatinine rose abruptly, 30.3% [15.1-46.2] in patients aged ≤ 10 days, and 15.1% [5.9-25.5] in older ones. However, only 41.3% of all patients who died had an abrupt increase in creatinine. ΔsCr improved prediction in survivors, but not in patients who died, and did not improve discrimination over a clinical mortality model. CONCLUSIONS: The present results suggest that a postoperative decrease in creatinine represents the normal course in neonates and infants with cardiac surgery, and that early creatinine variations lack sensitivity for the assessment of the severity of

  15. Features of cerebral blood flow, cardiac arrhythmias and conduction disturbances in patients with essential hypertension stage II associated with occlusive and stenotic lesions of brachiocephalic arteries

    Directory of Open Access Journals (Sweden)

    Vizir V.A.

    2015-09-01

    Full Text Available Arterial hypertension is the most common disease of the cardiovascular system in industrially advanced countries. With the aim to determine the characteristics of cerebral blood flow, disorders of cardiac rhythm and conduction in patients with stage 2 hypertension associated with stenotic and occlusive lesions of brachiocephalic arteries, cerebral blood flow indicators were studied in 87 patients using duplex scanning of extracranial arteries and Holter ECG monitoring. It was established that linear blood flow velocity was considerably decreased in the basins of the internal and common carotid artery; cerebral blood flow asymmetry was present in the course of the internal carotid artery. Evidence-based differences in structure of arrhythmias were revealed by single and paired ventricular extrasystoles, as well as episodes of unstable ventricular tachycardia. All this indicates the progressive decrease of elasticity and tonicity of vessel walls, intensified rigidity and sinuosity of carotid arteries, more severe disorders of cardiac rhythm and conduction in case of simultaneous hypertension and atherosclerotic lesion of brachiocephalic arteries.

  16. Advanced neutron source reactor probabilistic flow blockage assessment

    International Nuclear Information System (INIS)

    The Phase I Level I Probabilistic Risk Assessment (PRA) of the conceptual design of the Advanced Neutron Source (ANS) Reactor identified core flow blockage as the most likely internal event leading to fuel damage. The flow blockage event frequency used in the original ANS PRA was based primarily on the flow blockage work done for the High Flux Isotope Reactor (HFIR) PRA. This report examines potential flow blockage scenarios and calculates an estimate of the likelihood of debris-induced fuel damage. The bulk of the report is based specifically on the conceptual design of ANS with a 93%-enriched, two-element core; insights to the impact of the proposed three-element core are examined in Sect. 5. In addition to providing a probability (uncertainty) distribution for the likelihood of core flow blockage, this ongoing effort will serve to indicate potential areas of concern to be focused on in the preliminary design for elimination or mitigation. It will also serve as a loose-parts management tool

  17. Fourier analysis of multi-gated cardiac blood-pool data in patients with congenital heart diseases, (2). Assessment of diseases with complex cardiac anomalies, especially tetralogy of Fallot

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Kan; Maeda, Hisato; Yamaguchi, Nobuo; Nakamura, Kazuyoshi; Matsumura, Kaname; Nakagawa, Tsuyoshi; Sakurai, Minoru; Aoki, Kenzo

    1985-04-01

    The clinical usefulness of Fourier analysis of multi-gated cardiac blood-pool data was evaluated in 18 subjects with normal cardiac functions and 14 patients with complex cardiac anomalies (ten with tetralogy of Fallot, two with tricuspid atresia (TA), one with double-outlet right ventricle (DORV), and one with Ebstein's anomaly (EA)). Using global ventricular time-activity curves, the phase and amplitude at fundamental frequency were calculated, and emptying patterns of the left and right ventricles (LV, RV) were evaluated by phase difference (D(phase)=RV phase minus LV phase) and amplitude ratio of RV to LV (R(amp)). In patients with TOF, mean values of D (phase) and R(amp) were 25.3 +- 10.5 degrees and 13.5 +- 0.49 respectively and significantly larger than those of normal subjects. D (phase) became larger in inverse proportion to the ratio of pulmonary-to-systemic blood flow and there was an inverse linear correlation between these two variables. On visual interpretation of functional images, the dynamic property of hypoplastic ventricles could be easily estimated in patients with TA or DORV. In a case with EA, the atrialized RV was shown clearly as a hypokinetic, atrial phase area. This method is valuable for pathophysiologic investigation of diseases with complex cardiac anomalies. (author).

  18. POSSIBLE CARDIAC ADVERSE EFFECTS OF THERAPEUTIC DOSES OF MACROLIDE ANTIBIOTICS (AZITHROMYCIN AND CLARITHROMYCIN IN HEALTHY JUVENILE RATS: BIOCHEMICAL ASSESSMENT

    Directory of Open Access Journals (Sweden)

    Kassim Hassoon Ali

    2012-09-01

    Full Text Available The macrolides antibiotics inhibit bacterial protein synthesis by an effect on translocation. They include erythromycin, azithromycin, clarithromycin, and roxithromycin . Their antimicrobial spectrum is varied. The drugs are associated with QT interval prolongation and cardiac dysrhythmias. This study was designed to determine whether or not a therapeutic oral dose of either azithromycin or clarithromycin administered for 5 or 10 days, respectively have cardiac adverse effects in healthy juvenile rats by assessing serum enzymes (CK-MB, LDH, AST and ALT, as markers of cardiac function. Twenty-eight healthy juvenile rats of both sexes weighing approximately 30gm were utilized and were randomly subdivided into 4 groups, control group orally-administered distilled water (DW every 12hrs for 5 days via gavage tube, azithromycin suspension 12 mg/ kg every 12 hrs for 5 days via gavage tube, control group orally-administered DW every 12 hrs for 10 days via gavage tube and clarithromycin suspension 7.5 mg per kg for every 12 hrs for10 days via gavage tube. After scarification of animals by cervical dislocation, blood samples were taken by intra-cardiac puncture and utilized immediately to get serum in order to assess enzymes activities {heart creatin kinase isoform (CK-MB, lactate dehydrogenase (LDH, aspartate aminotransferase (AST and alanine aminotransferase (ALT}.The results of the present study demonstrated that were significant increase in serum activities of both CK-MB and LDH in group of animals treated with therapeutic oral dose of (12mg/kg azithromycin for 5 days compared to the corresponding serum enzyme activities of control animals. While, there were no significant increase in serum activities of both AST and ALT in group of animals treated with therapeutic oral dose of (12mg/kg azithromycin for 5 days compared to the corresponding serum enzyme activities of control group. Moreover, in groups of animals treated with therapeutic oral dose of (7

  19. Clinical assessment of cardiac performance in chronic lung diseases by using RI multi-gated cardiac pool scan and pulmonary artery catheterization

    International Nuclear Information System (INIS)

    To evaluate biventricular function at rest and hypoxic load in patients with chronic lung diseases, we examined radionuclide angiography in 6 normal controls, 19 patients with chronic obstructive lung diseases (COLD), 14 patients with restrictive lung diseases (RLD), using ECG-gated cardiac blood pool scans, and 7 patients (3 COLD, 4 RLD) were examined by the pulmonary artery catheter. After suitable background correction, left and right ventricular ejection fractions (LVEF and RVEF) were calulated by the formula : RVEF or LVEF = (end-diastole counts- end-systole counts)/end-diastole counts. Cardiac performance was measured at rest and after 20 minutes low oxygen (15 %) load. The results were as follows: 1) RVEF (%) at rest in the RLD group (46.6 ± 8.3 %) was less than that in the control group, and the COLD group (48.7 ± 8.7 %, 48.4 ± 12.4 %). 2) The responses to hypoxia in the COLD group and the RLD group showed absolute increases in RVEF of 8.7 ± 14.1 % and 7.4 ± 8.9 %, and also, mean pulmonary pressure (MPAP), cardiac index (CI) and pulmonary vascular resistance were increased significantly. These results suggest that in patients with chronic lung diseases, RV functions are after-hypoxic load-dependent and multiple cardiac pool image would be of value in the estimation of cardiac performance. (author)

  20. Assessment of myocardial infarction with delayed-enhancement MRI in coronary artery disease: a correlative study with cardiac events

    International Nuclear Information System (INIS)

    Objective: To investigate the correlation between recent cardiac events and the score of myocardial infarction by delayed-enhancement MRI (DE-MRI). Methods: DE-MRI was performed in 40 subjects with coronary artery disease. The score of myocardial infarction by DE-MRI, the ejection fraction (EF) by echocardiography, recent cardiac events (the number of weekly nitroglycerin, the number of weekly angina episodes and the onset number of heart failure in the last year), 6-minute walking distance, as well as the Seattle angina questionnaire (SAQ) score were assessed. The Spearman correlation test and Kruskal-Wallis test, Mann-Whitney test were used for the statistics. Results: There were negative correlation between the myocardial infarction score by DE-MRI (median 12, inter-quartile range: 6.0-19.8) and the 6-minute walking distance (378.93±100.53), SAQ score (74.55±11.40) (r was 0.66 and 0.54, P< 0.05). The myocardial infarction score by DE-MRI was strongly correlated with the number of weekly nitroglycerin (median 1; inter-quartile range: 0-2.8), the number of weekly angina episodes (median 3, inter-quartile range: 1-6.5) and the onset number of heart failure in the last year (median 0, inter-quartile range: 0-2) (r was 0.87, 0.85 and 0.89, P<0.05). EF [(49.2±13.72)%] was negative correlation with the number of weekly nitroglycerin, the number of weekly angina episodes and the onset number of heart failure in the last year (r were 0.67, 0.73 and 0.73, P<0.05). Conclusion: DE-MRI can be used for evaluation and prediction of future cardiac events. (authors)

  1. Assessment of splanchnic perfusion with gastric tonometry in the immediate postoperative period of cardiac surgery in children

    Directory of Open Access Journals (Sweden)

    Souza Renato Lopes de

    2001-01-01

    Full Text Available OBJECTIVE - A prospective, nonrandomized clinical study to assess splanchnic perfusion based on intramucosal pH in the postoperative period of cardiac surgery and to check the evolution of patients during hospitalization. METHODS - We studied 10 children, during the immediate postoperative period after elective cardiac surgery. Sequential intramucosal pH measurements were taken, without dobutamine (T0 and with 5mcg/kg/min (T1 and 10 (T2 mcg/kg/min. In the pediatric intensive care unit, intramucosal pH measurements were made on admission and 4, 8, 12, and 24 hours thereafter. RESULTS - The patients had an increase in intramucosal pH values with dobutamine 10mcg/kg/min [7.19± 0.09 (T0, 7.16±0.13(T1, and 7.32±0.16(T2], (p=0.103. During the hospitalization period, the intramucosal pH values were the following: 7.20±0.13 (upon admission, 7.27±0.16 (after 4 hours, 7.26±0.07 (after 8 hours, 7.32±0.12 (after 12 hours, and 7.38±0.08 (after 24 hours, (p=0.045. No deaths occurred, and none of the patients developed multiple organ and systems dysfunction. CONCLUSION - An increase in and normalization of intramucosal pH was observed after dobutamine use. Measurement of intramucosal pH is a type of monitoring that is easy to perform and free of complications in children during the postoperative period of cardiac surgery.

  2. SVM-based classification of LV wall motion in cardiac MRI with the assessment of STE

    Science.gov (United States)

    Mantilla, Juan; Garreau, Mireille; Bellanger, Jean-Jacques; Paredes, José Luis

    2015-01-01

    In this paper, we propose an automated method to classify normal/abnormal wall motion in Left Ventricle (LV) function in cardiac cine-Magnetic Resonance Imaging (MRI), taking as reference, strain information obtained from 2D Speckle Tracking Echocardiography (STE). Without the need of pre-processing and by exploiting all the images acquired during a cardiac cycle, spatio-temporal profiles are extracted from a subset of radial lines from the ventricle centroid to points outside the epicardial border. Classical Support Vector Machines (SVM) are used to classify features extracted from gray levels of the spatio-temporal profile as well as their representations in the Wavelet domain under the assumption that the data may be sparse in that domain. Based on information obtained from radial strain curves in 2D-STE studies, we label all the spatio-temporal profiles that belong to a particular segment as normal if the peak systolic radial strain curve of this segment presents normal kinesis, or abnormal if the peak systolic radial strain curve presents hypokinesis or akinesis. For this study, short-axis cine- MR images are collected from 9 patients with cardiac dyssynchrony for which we have the radial strain tracings at the mid-papilary muscle obtained by 2D STE; and from one control group formed by 9 healthy subjects. The best classification performance is obtained with the gray level information of the spatio-temporal profiles using a RBF kernel with 91.88% of accuracy, 92.75% of sensitivity and 91.52% of specificity.

  3. Assessment of Patient and Relatives Satisfaction in a Cardiac Surgery ICU Model

    Directory of Open Access Journals (Sweden)

    Kamran Shadvar

    2015-10-01

    Full Text Available Introduction: Evaluation of patients’ and their families’ satisfaction regarding the quality of care in the ICU is an important concern that can identify deficiencies of this field and help to improve satisfaction of both patients and their families. Considering the fact that problems related to cardiac surgery ICUs differ from other ICUs, recognition of these problems and the factors that lead to patient or family dissatisfaction can not only improve the quality and quantity of services provided in this section but also lead to increased satisfaction in these groups and promote scientific and practical knowledge related to sectors at regional levels. The aim of this study was to evaluate the satisfaction of patients and their families from the quantity and quality of services provided in the cardiac surgical ICU of Madani hospital, Tabriz, Iran. Materials and Methods: In this descriptive study, satisfaction of patients and their relatives from cardiac surgery ICU of Shahid Madani Hospital was evaluated using Modified MISS questionnaire for patients and CCMFNA questionnaires for their relatives during one year (1391-1390. The obtained data were statistically analyzed using descriptive statistics (frequency, percentage, mean ± SD and SPSS ver. 15. Results: Majority of patients expressed moderate to high satisfaction. The overall satisfaction of doctors was higher than nurses (27% vs. 22%. The lowest level of satisfaction related to the possibility of meeting relatives (14.3%. Most relatives were spouses of patients who contributed to the highest rate of satisfaction; however, the location and meets expectations were less satisfactory. Conclusion: Improving waiting room quality, increasing duration of family meetings and increasing nursing attention are the factors that could be associated with further satisfaction. Keywords: ICU; Patient satisfaction; Family satisfaction

  4. Real time assessment of RF cardiac tissue ablation with optical spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Demos, S G; Sharareh, S

    2008-03-20

    An optical spectroscopy approach is demonstrated allowing for critical parameters during RF ablation of cardiac tissue to be evaluated in real time. The method is based on incorporating in a typical ablation catheter transmitting and receiving fibers that terminate at the tip of the catheter. By analyzing the spectral characteristics of the NIR diffusely reflected light, information is obtained on such parameters as, catheter-tissue proximity, lesion formation, depth of penetration of the lesion, formation of char during the ablation, formation of coagulum around the ablation site, differentiation of ablated from healthy tissue, and recognition of micro-bubble formation in the tissue.

  5. Cardiac fusion and complex congenital cardiac defects in thoracopagus twins: diagnostic value of cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Park, Jeong-Jun [University of Ulsan College of Medicine, Asan Medical Center, Department of Pediatric Cardiac Surgery, Seoul (Korea, Republic of); Kim, Ellen Ai-Rhan [University of Ulsan College of Medicine, Asan Medical Center, Division of Neonatology, Department of Pediatrics, Seoul (Korea, Republic of); Won, Hye-Sung [University of Ulsan College of Medicine, Asan Medical Center, Department of Obstetrics and Gynecology, Seoul (Korea, Republic of)

    2014-09-15

    Most thoracopagus twins present with cardiac fusion and associated congenital cardiac defects, and assessment of this anatomy is of critical importance in determining patient care and outcome. Cardiac CT with electrocardiographic triggering provides an accurate and quick morphological assessment of both intracardiac and extracardiac structures in newborns, making it the best imaging modality to assess thoracopagus twins during the neonatal period. In this case report, we highlight the diagnostic value of cardiac CT in thoracopagus twins with an interatrial channel and complex congenital cardiac defects. (orig.)

  6. Clinical features and risk assessment for cardiac surgery in adult congenital heart disease: Three years at a single Japanese center

    Directory of Open Access Journals (Sweden)

    Satoshi Kurokawa

    2014-04-01

    Conclusion: Cardiac surgery could be safely performed in most ACHD cases. Exercise tolerance testing can be useful in identifying patients at high risk of mortality or major complications. BNP can be valuable in predicting poor outcomes after cardiac surgery.

  7. Assessing preferential flow by simultaneously injecting nanoparticle and chemical tracers

    KAUST Repository

    Subramanian, S. K.

    2013-01-01

    The exact manner in which preferential (e.g., much faster than average) flow occurs in the subsurface through small fractures or permeable connected pathways of other kinds is important to many processes but is difficult to determine, because most chemical tracers diffuse quickly enough from small flow channels that they appear to move more uniformly through the rock than they actually do. We show how preferential flow can be assessed by injecting 2 to 5 nm carbon particles (C-Dots) and an inert KBr chemical tracer at different flow rates into a permeable core channel that is surrounded by a less permeable matrix in laboratory apparatus of three different designs. When the KBr tracer has a long enough transit through the system to diffuse into the matrix, but the C-Dot tracer does not, the C-Dot tracer arrives first and the KBr tracer later, and the separation measures the degree of preferential flow. Tracer sequestration in the matrix can be estimated with a Peclet number, and this is useful for experiment design. A model is used to determine the best fitting core and matrix dispersion parameters and refine estimates of the core and matrix porosities. Almost the same parameter values explain all experiments. The methods demonstrated in the laboratory can be applied to field tests. If nanoparticles can be designed that do not stick while flowing through the subsurface, the methods presented here could be used to determine the degree of fracture control in natural environments, and this capability would have very wide ranging value and applicability.

  8. CT measurement of coronary calcium mass: impact on global cardiac risk assessment

    International Nuclear Information System (INIS)

    Coronary calcium mass percentiles can be derived from electron beam CT as well as from multidetector-row CT of all manufacturers. Coronary calcium mass may serve as a more individualized substitute for age for cardiac risk stratification. The aim was to investigate the potential impact of CT coronary calcium mass quantification on cardiac risk stratification using an adjusted Framingham score. Standardized coronary calcium mass was determined by multidetector-row CT in a total of 1,473 patients (1,038 male, 435 female). The impact on risk stratification of replacing the traditional Framingham age point score by a point score based on calcium mass relative to age was tested. Any coronary calcium found in males in the age group of 20-34 years and females in the age group of 20-59 years results in an increase of the Framingham score by 9 and 4-7 points, respectively. Only in males 65 years of age and older, none or minimal amounts of coronary calcium decrease the Framingham score by three points. The coronary calcium mass and age-related scoring system may have impact on the reassignment of patients with an intermediate Framingham risk to a lower or higher risk group. (orig.)

  9. Utilization of youtube as a tool to assess patient perception regarding implanted cardiac devices

    Directory of Open Access Journals (Sweden)

    Kevin Hayes

    2014-01-01

    Full Text Available Background: The outreach of YouTube may have a dramatic role in the widespread dissemination of knowledge on implantable cardioverter devices (ICD. Aims: This study was designed to review and analyze the information available on YouTube pertaining to implantable cardiac devices such as implantable cardioverter defibrillators (ICDs and pacemakers. Materials and Methods: YouTube was queried for the terms "ICD", "Implantable Cardioverter Defibrillator", and "Pacemaker". The videos were reviewed and categorized as according to content; number of views and "likes" or "dislikes" was recorded by two separate observers. Results: Of the 55 videos reviewed, 18 of the videos were categorized as patient education, 12 were advertisements, 8 were intraoperative videos documenting the device implantation procedures, 7 of the videos were produced to document personal patient experiences, and 4 were categorized as documentation of a public event. 3 were intended to educate health care workers. The remaining 3 were intended to raise public awareness about sudden cardiac death. The videos portraying intraoperative procedures generated the most "likes" or "dislikes" per view. Conclusion: While YouTube provides a logical platform for delivery of health information, the information on this platform is not regulated. Initiative by reputed authorities and posting accurate information in such platform can be a great aid in public education regarding device therapy.

  10. Assessment of sub-clinical acute cellular rejection after heart transplantation: comparison of cardiac magnetic resonance imaging and endomyocardial biopsy

    International Nuclear Information System (INIS)

    Comparing the diagnostic value of multi-sequential cardiac magnetic resonance imaging (CMR) with endomyocardial biopsy (EMB) for sub-clinical cardiac allograft rejection. One hundred and forty-six examinations in 73 patients (mean age 53 ± 12 years, 58 men) were performed using a 1.5 Tesla system and compared to EMB. Examinations included a STIR (short tau inversion recovery) sequence for calculation of edema ratio (ER), a T1-weighted spin-echo sequence for assessment of global relative enhancement (gRE), and inversion-recovery sequences to visualize late gadolinium enhancement (LGE). Histological grade ≥1B was considered relevant rejection. One hundred and twenty-seven (127/146 = 87 %) EMBs demonstrated no or mild signs of rejection (grades ≤1A) and 19/146 (13 %) a relevant rejection (grade ≥1B). Sensitivity, specificity, positive predictive, and negative predictive values were as follows: ER: 63 %, 78 %, 30 %, and 93 %; gRE: 63 %, 70 %, 24 %, and 93 %; LGE: 68 %, 36 %, 13 %, and 87 %; with the combination of ER and gRE with at least one out of two positive: 84 %, 57 %, 23 %, and 96 %. ROC analysis revealed an area under the curve of 0.724 for ER and 0.659 for gRE. CMR parameters for myocarditis are useful to detect sub-clinical acute cellular rejection after heart transplantation. Comparable results to myocarditis can be achieved with a combination of parameters. (orig.)

  11. Clinical evaluation of 64-slice CT assessment of global left ventricular function using automated cardiac phase selection

    International Nuclear Information System (INIS)

    Left ventricular (LV) function provides prognostic information regarding the morbidity and mortality of patients. An automated cardiac phase selection algorithm has the potential to support the assessment of LV function with computed tomography (CT). This algorithm is clinically evaluated for 64-slice cardiac CT. Examinations of twenty consecutive patients were selected. Electrocardiogram gated contrast-enhanced CT was performed. Reconstructions were performed using an automated and a manual method, followed by the determination of the global LV function. Significances were tested using 2-sided Student's t-tests. Reduction in post processing time and storage capacity were estimated. A slightly smaller mean end-systolic volume was found with the automated method (52±18 ml vs 54±17 ml, p=0.02, r=0.99). The mean LV ejection fraction was slightly larger with the automated method (65±8% vs 64±8%, p=0.004, r=0.99). The estimated reduction in post processing time was maximal 5 min per patient with a potential 80% data storage reduction. Results of the automated phase selection algorithm are similar to the manual method. The automated tool reduces post processing time, reconstruction time and transfer time. (author)

  12. Assessment of normal left atrial appendage anatomy and function over gender and ages by dynamic cardiac CT

    International Nuclear Information System (INIS)

    The aim of this study was to evaluate variations in anatomy and function according to age and gender using cardiac computed tomography (CT) in a large prospective cohort of healthy patients. The left atrial appendage (LAA) is considered the most frequent site of intracardiac thrombus formation. However, variations in normal in vivo anatomy and function according to age and gender remain largely unknown. Three-dimensional (3D) cardiac reconstructions of the LAA were performed from CT scans of 193 consecutive patients. Parameters measured included LAA number of lobes, anatomical position of the LAA tip, angulation measured between the proximal and distal portions, minimum (iVolmin) and maximum (iVolmax) volumes indexed to body surface area (BSA), and ejection fraction (LAAEF). Relationship with age was assessed for each parameter. We found that men had longer and wider LAAs. The iVolmin and iVolmax increased by 0.23 and 0.19 ml per decade, respectively, while LAAEF decreased by 2 % per decade in both sexes. Although LAA volumes increase, LAAEF decreases with age in both sexes. (orig.)

  13. Assessment of normal left atrial appendage anatomy and function over gender and ages by dynamic cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Boucebci, Samy; Velasco, Stephane; Duboe, Pier-Olivier; Tasu, Jean-Pierre [University of Poitiers, University Hospital, Department of Radiology, Poitiers (France); Pambrun, Thomas [University of Poitiers, University Hospital, Department of Cardiology, Poitiers (France); Ingrand, Pierre [University of Poitiers, University Institute of Public Health, Poitiers (France)

    2016-05-15

    The aim of this study was to evaluate variations in anatomy and function according to age and gender using cardiac computed tomography (CT) in a large prospective cohort of healthy patients. The left atrial appendage (LAA) is considered the most frequent site of intracardiac thrombus formation. However, variations in normal in vivo anatomy and function according to age and gender remain largely unknown. Three-dimensional (3D) cardiac reconstructions of the LAA were performed from CT scans of 193 consecutive patients. Parameters measured included LAA number of lobes, anatomical position of the LAA tip, angulation measured between the proximal and distal portions, minimum (iVol{sub min}) and maximum (iVol{sub max}) volumes indexed to body surface area (BSA), and ejection fraction (LAAEF). Relationship with age was assessed for each parameter. We found that men had longer and wider LAAs. The iVol{sub min} and iVol{sub max} increased by 0.23 and 0.19 ml per decade, respectively, while LAAEF decreased by 2 % per decade in both sexes. Although LAA volumes increase, LAAEF decreases with age in both sexes. (orig.)

  14. Assessment of sub-clinical acute cellular rejection after heart transplantation: comparison of cardiac magnetic resonance imaging and endomyocardial biopsy

    Energy Technology Data Exchange (ETDEWEB)

    Krieghoff, Christian; Hildebrand, Lysann; Grothoff, Matthias; Lehmkuhl, Lukas; Luecke, Christian; Andres, Claudia; Nitzsche, Stefan; Riese, Franziska; Gutberlet, Matthias [University Leipzig - Heart Centre, Department of Diagnostic and Interventional Radiology, Leipzig (Germany); Barten, Markus J.; Strueber, Martin; Mohr, Friedrich Wilhelm [University Leipzig - Heart Centre, Department of Cardiac Surgery, Leipzig (Germany)

    2014-10-15

    Comparing the diagnostic value of multi-sequential cardiac magnetic resonance imaging (CMR) with endomyocardial biopsy (EMB) for sub-clinical cardiac allograft rejection. One hundred and forty-six examinations in 73 patients (mean age 53 ± 12 years, 58 men) were performed using a 1.5 Tesla system and compared to EMB. Examinations included a STIR (short tau inversion recovery) sequence for calculation of edema ratio (ER), a T1-weighted spin-echo sequence for assessment of global relative enhancement (gRE), and inversion-recovery sequences to visualize late gadolinium enhancement (LGE). Histological grade ≥1B was considered relevant rejection. One hundred and twenty-seven (127/146 = 87 %) EMBs demonstrated no or mild signs of rejection (grades ≤1A) and 19/146 (13 %) a relevant rejection (grade ≥1B). Sensitivity, specificity, positive predictive, and negative predictive values were as follows: ER: 63 %, 78 %, 30 %, and 93 %; gRE: 63 %, 70 %, 24 %, and 93 %; LGE: 68 %, 36 %, 13 %, and 87 %; with the combination of ER and gRE with at least one out of two positive: 84 %, 57 %, 23 %, and 96 %. ROC analysis revealed an area under the curve of 0.724 for ER and 0.659 for gRE. CMR parameters for myocarditis are useful to detect sub-clinical acute cellular rejection after heart transplantation. Comparable results to myocarditis can be achieved with a combination of parameters. (orig.)

  15. ASSESSMENT OF DIASTOLIC FUNCTION BY COMBINED TRNSMITRAL AND PULMONARY VENOUS FLOW VELOCITY CURVES

    Directory of Open Access Journals (Sweden)

    Nagabhushana

    2014-04-01

    Full Text Available BACKGROUND: Several clinical studies have reported that 30% to 50% of patients with congestive heart failure have preserved left ventricular systolic function and isolated diastolic dysfunction. Detection of diastolic dysfunction is important factor in cardiac evaluation of hypertensives. MATERIAL AND METHODS: retrospective study carried out in Medicine department, SIMS, Shimoga for one year from Jan 2013 to Jan 2014. 50 patients who are hypertensive without any abnormality were studied general and systemic examination done, 2d echocardiography done in which transmitral flow velocity (E/A and pulmonary venous A duration- mitral A duration (∆d is measured. RESULT: 32% of subjects were newly diagnosed hypertensives in our study. 56% of cases had normal diastolic function as defined by E/A ratio (>1, 18% of cases in our study with normal E/A ratio were found to have pseudonormal pattern of diastolic function. LVDD of 62% is found in this study. CONCLUSION: The abnormal diastolic function as assessed by abnormal E/A ratio was seen in 44% of cases. Abnormal ∆d was found in 18% of cases out of 56% who had normal E/A ratio. These cases are said to have ‘pseudonormal’ pattern of diastolic function. The current study demonstrated that the presence of LV diastolic dysfunction in hypertensive patients is actually greater than previously reported by studies that analyzed transmitral flow velocity curves alone. To avoid overlooking patients with diastolic dysfunction, the combined analysis of transmitral and pulmonary venous flow velocity curves is recommended.

  16. A bioelectronic system for the monitoring of cardiac activity in mussels and crabs and its application in environmental assessments

    DEFF Research Database (Denmark)

    Kholodkevich, Sergey V.; Kuznetsova, Tatiana; Lehtonen, Kari;

    , SRCES RAS has carried out studies contributing to ecosystem health assessment basing on evaluation of the physiological state of organisms by the means of noninvasive fiber-optic monitoring of heartbeat of selected invertebrate species (Mytilus edulis, Macoma balthica, Carcinus maenas). During the 2...... mollusks and crabs under standard test stimuli and the development of new biomarkers based on heart rate of aquatic invertebrates. Responses to treatments with standard test stimuli provide integral information of the adaptive capacities of organisms. The results of these studies demonstratedsignificant...... geographical variability in cardiac responses in organisms related to the ecological/pollution status of the studied sites. Conclusively, the system for non-invasive monitoring of heart rate and its variability in selected invertebrates developed and tested under the BEAST project can be applied as an early...

  17. Detailed free span assessment for Mexilhao flow lines

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Antonio; Franco, Luciano; Eigbe, Uwa; BomfimSilva, Carlos [INTECSEA, Houston, TX (United States); Escudero, Carlos [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2009-07-01

    The subsea gas production system of Mexilhao Field SPS-35, Santos Basin, offshore Brazil, is composed basically of two rigid 12.75 inches production flow lines approximately 21 km long installed in a fairly rough seabed. During the basic design, the free span assessment was performed considering the maximum allowable free span length determined by the response model proposed by DNV-RP-F105. This approach resulted in a large number of predicted free span requiring corrections, leading to a higher capital cost for the project. In this sense, a detailed free span VIV fatigue assessment was proposed, considering multi-spans and multi-mode effects and also the post lay survey data. The assessment followed the DNV-RP-F105 recommendations for multi-spans and multi-mode effects, using Finite Element Analysis to determine the natural frequencies, mode shapes and corresponding stresses associated with the mode shapes. The assessment was performed in three stages, the first during the detailed design as part of the bottom roughness analysis using the expected residual pipelay tension. The second stage was performed after pipelay, considering the post-lay survey data, where the actual requirements for span correction were determined. Actual pipelay tension was used and seabed soil stiffness adjusted in the model to match the as-laid pipeline profile obtained from the survey data. The first and second stage assessments are seamlessly automated to speed up the evaluation process and allow for quick response in the field, which was important to keep the construction vessel time minimized. The third stage was performed once the corrections of the spans were made and the purpose was to confirm that the new pipeline configuration along the supported spans had sufficient fatigue life for the temporary and operational phases. For the assessment of all three stages, the probability of occurrence and directionality of the near bottom current was considered to improve prediction of the

  18. Tools for assessing quality of life in cardiology and cardiac surgery.

    Science.gov (United States)

    Gierlaszyńska, Karolina; Pudlo, Robert; Jaworska, Izabela; Byrczek-Godula, Kamila; Gąsior, Mariusz

    2016-03-01

    The holistic concept of health, popularization of knowledge, as well as social and economic factors have contributed to the growing interest in research concerning quality of life in cardiovascular diseases. The value of direct measurements of the patient's well-being and the extent of their functioning in everyday life (i.e., health-related quality of life; HRQoL) has gained appreciation. Questionnaires are the most popular method of measuring quality of life. On the basis of the literature, we can conclude that the Short-Form Health Survey (SF-36) questionnaire is one of the most widely used tools measuring the quality of life of patients undergoing cardiological treatment and cardiac surgery. PMID:27212988

  19. Development and assessment of the CONTAIN hybrid flow solver

    International Nuclear Information System (INIS)

    A new gravitational head formulation for the treatment of stratified flows has been developed for CONTAIN, a lumped-parameter code used primarily for the analysis of postulated accidents in nuclear power plants. This new hybrid formulation is discussed and compared in this paper with the old, average-density CONTAIN formulation. In addition, these formulations are assessed against experimental data from three large-scale experiments in which stratified conditions were observed. These are the NUPEC M-8-1, Surtsey ST-3, and the HDR E11.2 experiments

  20. Assessment of nonpenetrating captive bolt stunning followed by electrical induction of cardiac arrest in veal calves.

    Science.gov (United States)

    Bartz, B; Collins, M; Stoddard, G; Appleton, A; Livingood, R; Sobcynski, H; Vogel, K D

    2015-09-01

    The purpose of this study was to evaluate the impact of nonpenetrating captive bolt stunning followed by electrical induction of cardiac arrest on veal calf welfare, veal quality, and blood yield. Ninety calves from the same farm were randomly assigned to 1 of 2 treatment groups in a balanced unpaired comparison design. The first treatment group (the "head-only" method-application of the pneumatic nonpenetrating stun to the frontal plate of the skull at the intersection of 2 imaginary lines extending from the lateral canthus to the opposite poll [CONTROL]) was stunned with a nonpenetrating captive bolt gun ( = 45). The second group ( = 45) was stunned with a nonpenetrating captive bolt gun followed by secondary electrical induction of cardiac arrest (the "head/heart" method-initial application of the pneumatic nonpenetrating captive bolt stun followed by 1 s application of an electrical stun to the ventral region of the ribcage directly caudal to the junction of the humerus and scapula while the stunned calf was in lateral recumbence [HEAD/HEART]). Stunning efficacy was the indicator of animal welfare used in this study. All calves were instantly rendered insensible by the initial stun and did not display common indicators of return to consciousness. For meat quality evaluation, all samples were collected from the 12th rib region of the longissimus thoracis. Meat samples were evaluated for color, drip loss, ultimate pH, cook loss, and Warner-Bratzler shear force. The L* values (measure of meat color lightness) were darker ( 0.05) observed in a* (redness) and b* (yellowness) values between treatments. No differences ( > 0.05) were observed in drip loss, ultimate pH, cook loss, and Warner-Bratzler shear force. The blood yield from the CONTROL group (7,217.9 ± 143.5 g) was greater ( veal calves. PMID:26440354

  1. Postoperative cardiac arrest due to cardiac surgery complications

    International Nuclear Information System (INIS)

    To examine the role of anesthetists in the management of cardiac arrest occurring in association with cardiac anesthesia. In this retrospective study we studied the potential performances for each of the relevant incidents among 712 patients undergoing cardiac operations at Golestan and Naft Hospitals Ahwaz between November 2006 and July 2008. Out of total 712 patients undergoing cardiac surgery, cardiac arrest occurred in 28 cases (3.9%) due to different postoperative complications. This included massive bleeding (50% of cardiac arrest cases, 1.9% of patients); pulseless supra ventricular tachycardia (28.5% of cardiac arrest cases, 1.1% of patients); Heart Failure (7% of cardiac arrest cases, 0.2% of patients); Aorta Arc Rapture (3.5% of cardiac arrest cases, 0.1% of patients); Tamponade due to pericardial effusion (3.5% of cardiac arrest cases, 0.1% of total patients); Right Atrium Rupture (3.5% of cardiac arrest cases, 0.1% of patients) were detected after cardiac surgery. Out of 28 cases 7 deaths occurred (25% of cardiac arrest cases, 0.1% of patients). The most prevalent reason for cardiac arrest during post operative phase was massive bleeding (50%) followed by pulseless supra ventricular tachycardia (28.5%). Six patients had some morbidity and the remaining 15 patients recovered. There are often multiple contributing factors to a cardiac arrest under cardiac anesthesia, as much a complete systematic assessment of the patient, equipment, and drugs should be completed. We also found that the diagnosis and management of cardiac arrest in association with cardiac anesthesia differs considerably from that encountered elsewhere. (author)

  2. Real-time three-dimensional echocardiographic left ventricular ejection fraction and volumes assessment: comparison with cardiac computed tomography

    International Nuclear Information System (INIS)

    Background and objective: Few studies addressed the comparison between real-time 3D echocardiography (RT3DE) and cardiac computed tomography (CCT) concerning left ventricular ejection fraction and volumes assessment. We sought to compare both techniques regarding left ventricle (LV) ejection fraction function and volumes analysis. Methods: we studied by RT3DE (Philips IE 33, And, MA, USA) and by CCT (Toshiba, 64-slice, Otawara, Japan) 41 consecutive patients (29 males, 58 ± 11 yrs). We analysed by both techniques LVEF, LVEDV, LVESV. RT3DE and CCT data were compared by coefficients of determination (r: Pearson), Bland and Altman test and linear regression, 95% CI. Results: RT3DE data: LVEF ranged from 56.7 to 78.9 % (65.3 + 5.7 ); LVEDV ranged from 49.6 to 178.2 (88 + 27.5) mL; LVESV from 11.4 to 78 ( 33.9 + 13.7) mL. CCT data: LVEF ranged from 53 to 86 % (67.3 + 7.9 ); LVEDV ranged from 51 to 186 (106.4 + 30.7) mL; LVESV from 7 to 72 ( 35.1 + 13.8) mL. Correlations relative to RT3DE and CCT were: LVEF (r: 0. 7877, p<0.0001, 95 % CI 0.6327 to 0.8853 ); LVEDV (r:0.7671, p<0.0001, 95 % CI 0.5974 to 0.8745); LVESV (r: 0.8121, p<0.0001, 95 % CI 0.6659 to 0.8957). Conclusions: it was observed adequate correlation between real-time 3D echocardiography and cardiac computed tomography concerning ejection fraction and volumes assessment. (author)

  3. Cardiac catheterization and angiography. Third edition

    International Nuclear Information System (INIS)

    This book discusses the papers on cardiac catheterization and angiography. The topics covered are: historical perspective and present practice of cardiac catheterization; angiography principles and utilization of radiologic and cineangiographic equipment; complications, incidence and prevention of side effects of cardiac catheterization; techniques; blood flow measurement of heart; pressure measurement; diagnostic techniques of angiography; special catheter techniques; coronary angiography, temporary and permanent pacemakers, potential role of lasers in the cardiac catheterization and evaluation of cardiac function

  4. Assessment of TRAC codes with dartmouth college countercurrent flow tests

    International Nuclear Information System (INIS)

    The TRAC series of codes was developed to simulate pressurized water reactors (PWRs) and boiling water reactors (BWRs) under hypothetical accident conditions. The thermal hydraulics of these codes are based on a two-fluid formulation. These codes were applied to the Dartmouth College countercurrent flow tests to assess the ability of the interfacial momentum transfer models in the code to predict the countercurrent behavior. The TRAC-BD1 code, developed for the BWR analysis, qualitatively predicted the proper countercurrent flow behavior, but always overpredicted the liquid downflow. This led to the conclusion that interfacial momentum transfer in the annular regime was underestimated. The PWR version of the TRAC code, TRAC-PF1, had better agreement with the data but computed unusual behavior for the 0.152-m-i.d. pipe due to the use of Dukler's correlation outside the data base. The code prediction improved when Bharathan-Wallis' correlation was incorporated into this code. The correlations based on cocurrent data were not accurate in predicting countercurrent flows

  5. Assessment of maternal cerebral blood flow in patients with preeclampsia

    Directory of Open Access Journals (Sweden)

    Mandić Vesna

    2005-01-01

    Full Text Available Introduction Systemic vasoconstrktion in preeclamptic patients increases vascular resistance, and is manifested by increased arterial blood flow velocity. The aim of the study is to evaluate if there is a change of Doppler indices in maternal medial cerbral artery (MCA in severe preeclampsia due to: 1 severity of clinical symptoms, 2 the beginning of eclamptic attack and 3 the application of anticonvidsive therapy. Material and methods A prospective clinical study included 92 pregnant women, gestational age 28-36 weeks. They were divided into three groups: normotensive (n=30, mild preeclampsia (n=33, and severe preeclampsia (n=29. We investigated maternal cerebral circulation by assessing the MCA. We registrated: pulsatility index (Pi, resistance index (Ri, Systolic/diastolic ratio (S/D, and the maximum systolic, end diastolic and medium velocity. Patients with severe preeclampsia were divided into two subgroups: subgroup 1 included patients without symptoms of threatening eclampsia (n=18; 62.06%; while subgroup 2 included those with symptoms of preeclampsia (n=11; 37.94%. All patients with severe preeclampsia were treated with magnesium sulfate (MgSO4, and cerebral blood flow was measured before and after the treatment. Statistical analysis was done by oneway ANOVA, Student t-test and t-paired sample test. The difference was considered to be significant if p < 0.05. Results Significantly increased Pi, Ri and all velocities were established in the group of patients with severe preeclampsia compared with the other two groups. In the group with severe preeclamsia we registrated significantly increased values of all velocities (patients with signs of threatening eclampsia. After MgSO4 treatment in patients with severe preeclampsia significantly decreased values of Pi, Ri, S/D ratio and all velocities were registered. Discussion In the studied group of patients with severe preclampsia we found increased velocity values, Pi and Ri, especially in

  6. Risk modeling, assessment, and management of lahar flow threat.

    Science.gov (United States)

    Leung, M F; Santos, J R; Haimes, Y Y

    2003-12-01

    The 1991 eruption of Mount Pinatubo in the Philippines is considered one of the most violent and destructive volcanic activities in the 20th century. Lahar is the Indonesian term for volcanic ash, and lahar flows resulting from the massive amount of volcanic materials deposited on the mountain's slope posed continued post-eruption threats to the surrounding areas, destroying lives, homes, agricultural products, and infrastructures. Risks of lahar flows were identified immediately after the eruption, with scientific data provided by the Philippine Institute of Volcanology, the U.S. Geological Survey, and other research institutions. However, competing political, economic, and social agendas subordinated the importance of scientific information to policy making. Using systemic risk analysis and management, this article addresses the issues of multiple objectives and the effective integration of scientific techniques into the decision-making process. It provides a modeling framework for identifying, prioritizing, and evaluating policies for managing risk. The major considerations are: (1) applying a holistic approach to risk analysis through hierarchical holographic modeling, (2) applying statistical methods to gain insight into the problem of uncertainty in risk assessment, (3) using multiobjective trade-off analysis to address the issue of multiple decisionmakers and stakeholders in the decision-making process, (4) using the conditional expected value of extreme events to complement and supplement the expected value in quantifying risk, and (5) assessing the impacts of multistage decisions. Numerical examples based on ex post data are formulated to illustrate applications to various problems. The resulting framework from this study can serve as a general baseline model for assessing and managing risks of natural disasters, which the Philippines' lead agency-the National Disaster Coordinating Council (NDCC)-and other related organizations can use for their decision

  7. Quantitative assessment of small animal cardiac 18F-FDG PET and MRI image

    International Nuclear Information System (INIS)

    Cardiac disease research relies increasingly on small animal models and non-invasive imaging methods such as positron emission tomography (PET) and magnetic resonance imaging (MRI). Delayed enhancement magnetic resonance imaging (DE-MRI) using gadolinium-based contrast agents appear to be a visualizing infracted myocardium with high spatial resolution. Polar map (or bull's-eye image) was used to determination of the myocardial infarction area. Polar map is a comprehensive interpretation of the left ventricle. The infarct size was computed as the fraction of the total polar map areas. The threshold was computed as the percentage of mean intensity of the normal region. In other study, 50% predefined threshold value in varying range (30∼70%) was most commonly use. However, predefined threshold value isn't acceptance in all case. The purpose of this study was to investigate methodological approach for automatic measurement of rat myocardial infarct size using PET and MRI polar map with adaptive threshold value driven from Multi gaussian mixture model (MGMM)

  8. Pulmonary infection in patients with cyclosporine, azathioprine, and corticosteroids after cardiac transplantation; Clinical and radiographic assessment

    Energy Technology Data Exchange (ETDEWEB)

    Murayama, Sadayuki; Ikezoe, Junpei; Godwin, J.D.; Marglin, S.I.; Allen, M.D. (University of Washington Medical Center, Seattle, WA (United States))

    1991-07-01

    Between November 1985 and November 1989, 54 patients have undergone 55 cardiac transplants, 5 of whom died during operation or one week after transplantation. The remaining 49 patients with a minimum follow-up of 5 months were studied to examine pulmonary infection clinically and radiologically while receiving triple drug immunosuppression consisting of cyclosporine, azathioprine, and prednisolone. Pulmonary infection occurred in 14 patients (29%) with a total of 21 occasions. Causative organisms were identified in 9 occasions, with the most common organism being Cytomegalovirus (CMV). One patient died of pulmonary infection with Aspergillus. Causative organisms occurring in the remaining 12 occasions of pulmonary infection were unknown, which did not lead to death. Because pulmonary infection of unknown organisms rapidly responded to convensional antibiotics, it seemed to have been caused by bacteria. Pulmonary infection of unknown organism occurred 13.2{+-}3.2 months after transplantation, as compared with 3.3{+-}1.0 months in pulmonary infection of known organisms. Chest plain radiographic features fell into four types: (1) interstitial shadow seen in pulmonary infection of CMV, Pneumocystis carinii, or Hemophilia influenza, (2) patchy, and basilar and lobular consolidation shadows in bacterial pneumonia, (3) localized nodular shadow in aspergillosis, and (4) multiple patchy and confluent opacity patterns occurring in herpes simplex viral infection. Pulmonary infection of influenza bacteria for one patient and pulmonary infection of unknown organisms for 4 patients were difficult to identify from pulmonary infection of CMV. (N.K.).

  9. Absorbed dose assessment of cardiac and other tissues around the cardiovascular system in brachytherapy with 90Sr/90Y source by Monte Carlo simulation

    International Nuclear Information System (INIS)

    Cardiac disease is one of the most important causes of death in the world. Coronary artery stenosis is a very common cardiac disease. Intravascular brachytherapy (IVBT) is one of the radiotherapy methods which have been used recently in coronary artery radiation therapy for the treatment of restenosis. 90Sr/90Y, a beta-emitting source, is a proper option for cardiovascular brachytherapy. In this research, a Monte Carlo simulation was done to calculate dosimetry parameters and effective equivalent doses to the heart and its surrounding tissues during IVBT. The results of this study were compared with the published experimental data and other simulations performed by different programs but with the same source of radiation. A very good agreement was found between results of this work and the published data. An assessment of the risk for cardiac and other sensitive soft tissues surrounding the treated vessel during 90Sr/90Y IVBT was also performed in the study. (authors)

  10. Protocol for the China PEACE (Patient-centered Evaluative Assessment of Cardiac Events) Million Persons Project pilot

    Science.gov (United States)

    Lu, Jiapeng; Xuan, Si; Downing, Nicholas S; Wu, Chaoqun; Li, Li; Krumholz, Harlan M; Jiang, Lixin

    2016-01-01

    Introduction Collection of high-quality data from large populations is considered essential to generate knowledge that is critical to an era of precision medicine. Cardiovascular disease (CVD) is a leading cause of mortality in China and is a suitable focus of an initiative to discover factors that would improve our ability to assess and modify individual risk. Methods and analysis The pilot phase of China PEACE (Patient-centered Evaluative Assessment of Cardiac Events) Million Persons Project is being conducted during 2014–2015 in four provinces across China to demonstrate the feasibility of a population-based assessment. It is designed to screen 0.4 million community-dwelling residents aged 40–75 years with measurements of blood pressure, height and weight, a lipid blood test, and a questionnaire on cardiovascular-related health status. Participants identified at high risk of CVD receive further health assessments, including ECG, ultrasound scan, blood and urine analysis, and a questionnaire on lifestyle and medical history. Collection of blood and urine samples is used to establish a biobank. High-risk subjects are also counselled with suggestions regarding potential lifestyle changes. In addition, high-risk subjects are followed-up either in a return clinic visit or by telephone interview, with measurement of blood pressure, weight, ECG, and a questionnaire on survival status, hospitalisations and lifestyle. The first 0.1 million participants screened were used to conduct a preliminary analysis, with information on baseline characteristics, health-related behaviours, anthropometric variables, medical history, and prevalence of high-risk subjects. Ethics and dissemination The central ethics committee at the China National Center for Cardiovascular Disease (NCCD) approved the pilot. Written informed consent is obtained from all participants on entry into the project. Findings will be disseminated in future peer-reviewed papers and will inform strategies

  11. In silico cardiac risk assessment in patients with long QT syndrome

    DEFF Research Database (Denmark)

    Hoefen, Ryan; Reumann, Matthias; Goldenberg, Ilan;

    2012-01-01

    The study was designed to assess the ability of computer-simulated electrocardiography parameters to predict clinical outcomes and to risk-stratify patients with long QT syndrome type 1 (LQT1).......The study was designed to assess the ability of computer-simulated electrocardiography parameters to predict clinical outcomes and to risk-stratify patients with long QT syndrome type 1 (LQT1)....

  12. Advances in cardiac magnetic resonance imaging of congenital heart disease

    International Nuclear Information System (INIS)

    Due to advances in cardiac surgery, survival of patients with congenital heart disease has increased considerably during the past decades. Many of these patients require repeated cardiovascular magnetic resonance imaging to assess cardiac anatomy and function. In the past decade, technological advances have enabled faster and more robust cardiovascular magnetic resonance with improved image quality and spatial as well as temporal resolution. This review aims to provide an overview of advances in cardiovascular magnetic resonance hardware and acquisition techniques relevant to both pediatric and adult patients with congenital heart disease and discusses the techniques used to assess function, anatomy, flow and tissue characterization. (orig.)

  13. Advances in cardiac magnetic resonance imaging of congenital heart disease.

    Science.gov (United States)

    Driessen, Mieke M P; Breur, Johannes M P J; Budde, Ricardo P J; van Oorschot, Joep W M; van Kimmenade, Roland R J; Sieswerda, Gertjan Tj; Meijboom, Folkert J; Leiner, Tim

    2015-01-01

    Due to advances in cardiac surgery, survival of patients with congenital heart disease has increased considerably during the past decades. Many of these patients require repeated cardiovascular magnetic resonance imaging to assess cardiac anatomy and function. In the past decade, technological advances have enabled faster and more robust cardiovascular magnetic resonance with improved image quality and spatial as well as temporal resolution. This review aims to provide an overview of advances in cardiovascular magnetic resonance hardware and acquisition techniques relevant to both pediatric and adult patients with congenital heart disease and discusses the techniques used to assess function, anatomy, flow and tissue characterization. PMID:25552386

  14. Advances in cardiac magnetic resonance imaging of congenital heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Driessen, Mieke M.P. [University of Utrecht, University Medical Center Utrecht, Department of Radiology, PO Box 85500, Utrecht (Netherlands); University of Utrecht, University Medical Center Utrecht, Department of Cardiology, PO Box 85500, Utrecht (Netherlands); The Interuniversity Cardiology Institute of the Netherlands (ICIN) - Netherlands Heart Institute, PO Box 19258, Utrecht (Netherlands); Breur, Johannes M.P.J. [Wilhelmina Children' s Hospital, University Medical Center Utrecht, Department of Pediatric Cardiology, PO Box 85500, Utrecht (Netherlands); Budde, Ricardo P.J.; Oorschot, Joep W.M. van; Leiner, Tim [University of Utrecht, University Medical Center Utrecht, Department of Radiology, PO Box 85500, Utrecht (Netherlands); Kimmenade, Roland R.J. van; Sieswerda, Gertjan Tj [University of Utrecht, University Medical Center Utrecht, Department of Cardiology, PO Box 85500, Utrecht (Netherlands); Meijboom, Folkert J. [University of Utrecht, University Medical Center Utrecht, Department of Cardiology, PO Box 85500, Utrecht (Netherlands); Wilhelmina Children' s Hospital, University Medical Center Utrecht, Department of Pediatric Cardiology, PO Box 85500, Utrecht (Netherlands)

    2015-01-01

    Due to advances in cardiac surgery, survival of patients with congenital heart disease has increased considerably during the past decades. Many of these patients require repeated cardiovascular magnetic resonance imaging to assess cardiac anatomy and function. In the past decade, technological advances have enabled faster and more robust cardiovascular magnetic resonance with improved image quality and spatial as well as temporal resolution. This review aims to provide an overview of advances in cardiovascular magnetic resonance hardware and acquisition techniques relevant to both pediatric and adult patients with congenital heart disease and discusses the techniques used to assess function, anatomy, flow and tissue characterization. (orig.)

  15. Pulsatile blood flow in human bone assessed by laser-Doppler flowmetry and the interpretation of photoplethysmographic signals

    International Nuclear Information System (INIS)

    Human bone blood flow, mean blood speed and the number of moving red blood cells were assessed (in arbitrary units), as a function of time, during one cardiac cycle. The measurements were obtained non-invasively on five volunteers by laser-Doppler flowmetry at large interoptode spacing. The investigated bones included: patella, clavicle, tibial diaphysis and tibial malleolus. As hypothesized, we found that in all bones the number of moving cells remains constant during cardiac cycles. Therefore, we concluded that the pulsatile nature of blood flow must be completely determined by the mean blood speed and not by changes in blood volume (vessels dilation). Based on these results, it is finally demonstrated using a mathematical model (derived from the radiative transport theory) that photoplethysmographic (PPG) pulsations observed by others in the literature, cannot be generated by oscillations in blood oxygen saturation, which is physiologically linked to blood speed. In fact, possible oxygen saturation changes during pulsations decrease the amplitude of PPG pulsations due to specific features of the PPG light source. It is shown that a variation in blood oxygen saturation of 3% may induce a negative change of ∼1% in the PPG signal. It is concluded that PPG pulsations are determined by periodic ‘positive’ changes of the reduced scattering coefficient of the tissue and/or the absorption coefficient at constant blood volume. No explicit experimental PPG measurements have been performed. As a by-product of this study, an estimation of the arterial pulse wave velocity obtained from the analysis of the blood flow pulsations give a value of 7.8 m s−1 (95% confidence interval of the sample mean distribution: [6.7, 9.5] m s−1), which is perfectly compatible with data in the literature. We hope that this note will contribute to a better understanding of PPG signals and to further develop the domain of the vascular physiology of human bone. (note)

  16. Unrecognized Myocardial Infarction Assessed by Cardiac Magnetic Resonance Imaging--Prognostic Implications.

    Directory of Open Access Journals (Sweden)

    Anna M Nordenskjöld

    Full Text Available Clinically unrecognized myocardial infarctions (UMI are not uncommon and may be associated with adverse outcome. The aims of this study were to determine the prognostic implication of UMI in patients with stable suspected coronary artery disease (CAD and to investigate the associations of UMI with the presence of CAD.In total 235 patients late gadolinium enhancement cardiovascular magnetic resonance (LGE-CMR imaging and coronary angiography were performed. For each patient with UMI, the stenosis grade of the coronary branch supplying the infarcted area was determined. UMIs were present in 25% of the patients and 67% of the UMIs were located in an area supplied by a coronary artery with a stenosis grade ≥70%. In an age- and gender-adjusted model, UMI independently predicted the primary endpoint (composite of death, myocardial infarction, resuscitated cardiac arrest, hospitalization for unstable angina pectoris or heart failure within 2 years of follow-up with an odds ratio of 2.9; 95% confidence interval 1.1-7.9. However, this association was abrogated after adjustment for age and presence of significant coronary disease. There was no difference in the primary endpoint rates between UMI patients with or without a significant stenosis in the corresponding coronary artery.The presence of UMI was associated with a threefold increased risk of adverse events during follow up. However, the difference was no longer statistically significant after adjustments for age and severity of CAD. Thus, the results do not support that patients with suspicion of CAD should be routinely investigated by LGE-CMR for UMI. However, coronary angiography should be considered in patients with UMI detected by LGE-CMR.ClinicalTrials.gov NTC01257282.

  17. CIS-Based Risk Assessment of Debris Flow Disasters in the Upper Reach of Yangtze River

    Institute of Scientific and Technical Information of China (English)

    HAN Yongshun; LIU Hongjiang; ZHONG Dunlun; SU Fenghuan; LI Chaokui

    2007-01-01

    This paper discussed theory and methodologies of debris-flow risk assessment and established an implementation process according to indicators of debris-flow hazard degree, vulnerability, risk degree, etc. Among these methodologies, historical and potential hazard degree was comprehensively considered into hazard assessment and hazard index was presented to indicate the debris-flow hazard degree. Regarding debris-flow vulnerability assessment, its statistical data and calculating procedure were based on the hazard-degree regionalization instead of administrative divisions, which improved the assessing scientificity and precision. These quantitative methodologies integrated with Geography Information System (GIS) were applied to the risk assessment of debris flows in the upper reach of Yangtze River. Its results were in substantial agreement on investigation data and the actual distribution of debris flows, which showed that these principles and methodologies were reasonable and feasible and can provide basis or reference for debris-flow risk assessment and disaster management.

  18. Cardiac MRI assessed left ventricular hypertrophy in differentiating hypertensive heart disease from hypertrophic cardiomyopathy attributable to a sarcomeric gene mutation

    International Nuclear Information System (INIS)

    To evaluate the value of cardiac magnetic resonance imaging (CMRI)-assessed left ventricular hypertrophy (LVH) in differentiating between hypertensive heart disease and hypertrophic cardiomyopathy (HCM). 95 unselected subjects with mild-to-moderate hypertension, 24 patients with HCM attributable to the D175N mutation of the α-tropomyosin gene and 17 control subjects were studied by cine CMRI. Left ventricular (LV) quantitative and qualitative characteristics were evaluated. LV maximal end-diastolic wall thickness, wall thickness-to-LV volume ratio, end-diastolic septum thickness and septum-to-lateral wall thickness ratio were useful measures for differentiating between LVH due to hypertension and HCM. The most accurate measure for identifying patients with HCM was the LV maximal wall thickness ≥17 mm, with a sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of 90%, 93%, 86%, 95% and 91%, respectively. LV maximal wall thickness in the anterior wall, or regional bulging in left ventricular wall was found only in patients with HCM. LV mass index was not discriminant between patients with HCM and those with LVH due to hypertension. LV maximal thickness measured by CMRI is the best anatomical parameter in differentiating between LVH due to mild-to-moderate hypertension and HCM attributable to a sarcomeric mutation. CMRI assessment of location and quality of LVH is also of value in differential diagnosis. (orig.)

  19. Cardiac MRI assessed left ventricular hypertrophy in differentiating hypertensive heart disease from hypertrophic cardiomyopathy attributable to a sarcomeric gene mutation

    Energy Technology Data Exchange (ETDEWEB)

    Sipola, Petri [Kuopio University Hospital, Department of Clinical Radiology, Kuopio (Finland); University of Eastern Finland, Institute of Clinical Medicine, Faculty of Health Sciences, Kuopio (Finland); Magga, Jarkko; Peuhkurinen, Keijo [Kuopio University Hospital, Department of Medicine, Kuopio (Finland); Husso, Minna [Kuopio University Hospital, Department of Clinical Radiology, Kuopio (Finland); Jaeaeskelaeinen, Pertti; Kuusisto, Johanna [Kuopio University Hospital, Department of Medicine, Kuopio (Finland); Kuopio University Hospital, Heart Center, P.O. Box 1777, Kuopio (Finland)

    2011-07-15

    To evaluate the value of cardiac magnetic resonance imaging (CMRI)-assessed left ventricular hypertrophy (LVH) in differentiating between hypertensive heart disease and hypertrophic cardiomyopathy (HCM). 95 unselected subjects with mild-to-moderate hypertension, 24 patients with HCM attributable to the D175N mutation of the {alpha}-tropomyosin gene and 17 control subjects were studied by cine CMRI. Left ventricular (LV) quantitative and qualitative characteristics were evaluated. LV maximal end-diastolic wall thickness, wall thickness-to-LV volume ratio, end-diastolic septum thickness and septum-to-lateral wall thickness ratio were useful measures for differentiating between LVH due to hypertension and HCM. The most accurate measure for identifying patients with HCM was the LV maximal wall thickness {>=}17 mm, with a sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of 90%, 93%, 86%, 95% and 91%, respectively. LV maximal wall thickness in the anterior wall, or regional bulging in left ventricular wall was found only in patients with HCM. LV mass index was not discriminant between patients with HCM and those with LVH due to hypertension. LV maximal thickness measured by CMRI is the best anatomical parameter in differentiating between LVH due to mild-to-moderate hypertension and HCM attributable to a sarcomeric mutation. CMRI assessment of location and quality of LVH is also of value in differential diagnosis. (orig.)

  20. In Vivo Quantitative Assessment of Myocardial Structure, Function, Perfusion and Viability Using Cardiac Micro-computed Tomography.

    Science.gov (United States)

    van Deel, Elza; Ridwan, Yanto; van Vliet, J Nicole; Belenkov, Sasha; Essers, Jeroen

    2016-01-01

    The use of Micro-Computed Tomography (MicroCT) for in vivo studies of small animals as models of human disease has risen tremendously due to the fact that MicroCT provides quantitative high-resolution three-dimensional (3D) anatomical data non-destructively and longitudinally. Most importantly, with the development of a novel preclinical iodinated contrast agent called eXIA160, functional and metabolic assessment of the heart became possible. However, prior to the advent of commercial MicroCT scanners equipped with X-ray flat-panel detector technology and easy-to-use cardio-respiratory gating, preclinical studies of cardiovascular disease (CVD) in small animals required a MicroCT technologist with advanced skills, and thus were impractical for widespread implementation. The goal of this work is to provide a practical guide to the use of the high-speed Quantum FX MicroCT system for comprehensive determination of myocardial global and regional function along with assessment of myocardial perfusion, metabolism and viability in healthy mice and in a cardiac ischemia mouse model induced by permanent occlusion of the left anterior descending coronary artery (LAD). PMID:26967592

  1. Review and assessment of turbulence models for hypersonic flows

    Science.gov (United States)

    Roy, Christopher J.; Blottner, Frederick G.

    2006-10-01

    Accurate aerodynamic prediction is critical for the design and optimization of hypersonic vehicles. Turbulence modeling remains a major source of uncertainty in the computational prediction of aerodynamic forces and heating for these systems. The first goal of this article is to update the previous comprehensive review of hypersonic shock/turbulent boundary-layer interaction experiments published in 1991 by Settles and Dodson (Hypersonic shock/boundary-layer interaction database. NASA CR 177577, 1991). In their review, Settles and Dodson developed a methodology for assessing experiments appropriate for turbulence model validation and critically surveyed the existing hypersonic experiments. We limit the scope of our current effort by considering only two-dimensional (2D)/axisymmetric flows in the hypersonic flow regime where calorically perfect gas models are appropriate. We extend the prior database of recommended hypersonic experiments (on four 2D and two 3D shock-interaction geometries) by adding three new geometries. The first two geometries, the flat plate/cylinder and the sharp cone, are canonical, zero-pressure gradient flows which are amenable to theory-based correlations, and these correlations are discussed in detail. The third geometry added is the 2D shock impinging on a turbulent flat plate boundary layer. The current 2D hypersonic database for shock-interaction flows thus consists of nine experiments on five different geometries. The second goal of this study is to review and assess the validation usage of various turbulence models on the existing experimental database. Here we limit the scope to one- and two-equation turbulence models where integration to the wall is used (i.e., we omit studies involving wall functions). A methodology for validating turbulence models is given, followed by an extensive evaluation of the turbulence models on the current hypersonic experimental database. A total of 18 one- and two-equation turbulence models are reviewed

  2. Assessment of critical flow path for improved remediation management

    International Nuclear Information System (INIS)

    A multiple indicator conditional simulation technique is used to generate realizations of hydrofacies units in a two-dimensional section of the fluvial, unconfined aquifer on the Hanford Site, Richland, WA. Two conceptual geologic models are considered and evaluated for spatial connectivity. The two conceptual models yielded different probabilities of occurrence for three 'families' of simulations with distinct styles of connectivity. Critical ground-water flow paths of each simulated section are evaluated as the paths with the highest percent of high hydraulic conductivity hydrofacies. The effective hydraulic conductivity of these critical paths is evaluated analytically by computing harmonic averages. Estimated groundwater travel times are consistent with the observed rate of plume migration in the field. This procedure can be used to evaluate the probability of occurrence of alternative paths for contaminant transport as input to risk assessments, and design of characterization programs and remediation systems

  3. Atlas-based analysis of 4D flow CMR: Automated vessel segmentation and flow quantification

    OpenAIRE

    Bustamante, Mariana; Petersson, Sven; Eriksson, Jonatan; Alehagen, Urban; Dyverfeldt, Petter; Carlhäll, Carljohan; Ebbers, Tino

    2015-01-01

    Background Flow volume quantification in the great thoracic vessels is used in the assessment of several cardiovascular diseases. Clinically, it is often based on semi-automatic segmentation of a vessel throughout the cardiac cycle in 2D cine phase-contrast Cardiovascular Magnetic Resonance (CMR) images. Three-dimensional (3D), time-resolved phase-contrast CMR with three-directional velocity encoding (4D flow CMR) permits assessment of net flow volumes and flow patterns retrospectively at any...

  4. Relationship between adductor pollicis muscle thickness and subjective global assessment in a cardiac intensive care unit

    OpenAIRE

    Karst, Fernanda Pickrodt; Vieira, Renata Monteiro; Barbiero, Sandra

    2015-01-01

    Objective To verify the relationship between the adductor pollicis muscle thickness test and the subjective global assessment and to correlate it with other anthropometric methods. Methods This observational cross-sectional study was conducted in the intensive care unit of a cardiology hospital in the state of Rio Grande do Sul, Brazil. The hospitalized patients underwent subjective global assessment and adductor pollicis muscle thickness tests on both hands, along with measurement of the rig...

  5. Evaluation of changes of intracranial blood flow after carotid artery stenting using digital subtraction angiography flow assessment

    Institute of Scientific and Technical Information of China (English)

    Hajime; Wada; Masato; Saito; Kyousuke; Kamada

    2015-01-01

    AIM: To evaluate the changes of intracranial blood flow after carotid artery stenting(CAS), using the flow assessment application "Flow-Insight", which was developed in our department.METHODS: Twenty patients treated by CAS participated in this study. We analyzed the change in concentration of the contrast media at the anterior-posterior and profile view image with the flow assessment application "Flow-Insight". And we compared the results with N-isopropyl-p-[123I] iodoamphetamine-single-photon emission computed tomography(IMP SPECT) performed before and after the treatment. RESULTS: From this study, 200% of the parameter "blood flow" change in the post/pre-treatment is suggested as the critical line of the hyperperfusion syndrome arise. Although the observed blood flow increase in the digital subtraction angiography system did not strongly correlate with the rate of increase of SPECT, the "Flow-Insight" reflected the rate of change of the vessels well. However, for patients with reduced reserve blood flow before CAS, a highly elevated site was in agreement with the site analysis results. CONCLUSION: We concluded that the cerebral angiography flow assessment application was able to more finely reveal hyperperfusion regions in the brain after CAS compared to SPECT.

  6. Assessment of central chemosensitivity and cardiac sympathetic nerve activity using I-123 MIBG imaging in central sleep apnea syndrome in patients with dilated cardiomyopathy

    International Nuclear Information System (INIS)

    Iodine-123 m-iodobenzylguanidine (MIBG) imaging has been used to study cardiac sympathetic function in various cardiac diseases. Central sleep apnea syndrome (CSAS) occurs frequently in patients with chronic heart failure (CHF) and is reported to be associated with a poor prognosis. One of the mechanisms of its poor prognosis may be related to impaired cardiac sympathetic activity. However, the relationship between chemosensitivity to carbon dioxide, which is reported to correlate with the severity of CSAS, and cardiac sympathetic activity has not been investigated. Therefore, this study was undertaken to assess cardiac sympathetic function and chemosensitivity to carbon dioxide in CHF patients. The oxygen desaturation index (ODI) was evaluated in 21 patients with dilated cardiomyopathy (male/female: 19/2, left ventricular ejection fraction (LVEF)5 times/h underwent polysomnography. Patients with an apnea hypopnea index >15/h but without evidence of obstructive apnea were defined as having CSAS. Early (15 min) and delayed (4 hr) planar MIBG images were obtained from these patients. The mean counts in the whole heart and the mediastinum were obtained. The heart-to-mediastinum count ratio of the delayed image (H/M) and the corrected myocardial washout rate (WR) were also calculated. The central chemoreflex was assessed with the rebreathing method using a hypercapnic gas mixture (7% CO2 and 93% O2). Ten of the 21 patients had CSAS. The H/M ratio was similar in patients both with and without CSAS (1.57±0.18 vs. 1.59±0.14, p=0.82). However, the WR was higher in patients with CSAS than in patients without CSAS (40±8% vs. 30±12%, p<0.05). ODI significantly correlated with central chemosensitivity to carbon dioxide. Moreover, there was a highly significant correlation between WR and central chemosensitivity (r=0.65, p<0.05). However, there was no correlation between ODI and the WR (r=0.36, p=0.11). Cardiac sympathetic nerve activity in patients with CHF and CSAS is

  7. Diagnostic accuracy and variability of three semi-quantitative methods for assessing right ventricular systolic function from cardiac MRI in patients with acquired heart disease

    International Nuclear Information System (INIS)

    To evaluate the diagnostic accuracy and variability of 3 semi-quantitative (SQt) methods for assessing right ventricular (RV) systolic function from cardiac MRI in patients with acquired heart disease: tricuspid annular plane systolic excursion (TAPSE), RV fractional-shortening (RVFS) and RV fractional area change (RVFAC). Sixty consecutive patients were enrolled. Reference RV ejection fraction (RVEF) was determined from short axis cine sequences. TAPSE, RVFS and RVFAC were measured on a 4-chamber cine sequence. All SQt analyses were performed twice by 3 observers with various degrees of training in cardiac MRI. Correlation with RVEF, intra- and inter-observer variability, and receiver operating characteristic (ROC) curve analysis were performed for each SQt method. Correlation between RVFAC and RVEF was good for all observers and did not depend on previous cardiac MRI experience (R range = 0.716-0.741). Conversely, RVFS (R range = 0.534-0.720) and TAPSE (R range = 0.482-0.646) correlated less with RVEF and depended on previous experience. Intra- and inter-observer variability was much lower for RVFAC than for RVFS and TAPSE. ROC analysis demonstrated that RVFAC <41% could predict a RVEF <45% with 90% sensitivity and 94% specificity. RVFAC appears to be more accurate and reproducible than RVFS and TAPSE for SQt assessment of RV function by cardiac MRI. (orig.)

  8. Comprehensive cardiac rehabilitation

    DEFF Research Database (Denmark)

    Kruse, Marie; Hochstrasser, Stefan; Zwisler, Ann-Dorthe O;

    2006-01-01

    OBJECTIVES: The costs of comprehensive cardiac rehabilitation are established and compared to the corresponding costs of usual care. The effect on health-related quality of life is analyzed. METHODS: An unprecedented and very detailed cost assessment was carried out, as no guidelines existed for...... uncertain and may be as high as euro 1.877. CONCLUSIONS: Comprehensive cardiac rehabilitation is more costly than usual care, and the higher costs are not outweighed by a quality of life gain. Comprehensive cardiac rehabilitation is, therefore, not cost-effective....

  9. Improvement of skills and knowledge by a hands-on cardiac CT course. Before and after evaluation with a validated questionnaire and self-assessment

    International Nuclear Information System (INIS)

    Purpose: cardiac computed tomography (CT) is becoming increasingly important in noninvasive imaging. To meet this demand, there are a growing number of short training courses for cardiac CT. Whether such courses improve the knowledge and skills of participants is not known. Materials and methods: the concept of a two-day cardiac CT course consisting of introductory lectures, live patient examinations, and hands-on exercises for interpreting cardiac CT scans on workstations was analyzed using participant evaluations (scales from 1 = excellent to 6 = very poor). Participants rated their increase in knowledge and completed a validated questionnaire with 20 questions. Results: a total of 102 participants attended the courses. There were significant differences in the number of correctly answered test questions between cardiac CT experts and participants at the beginning of the course (91.5 ± 6.3% vs. 62.4 ± 16.1% p < 0.001). The number of questions answered correctly by the participants increased significantly after completion of the course (mean increase of 4 correctly answered questions, 81.8 ± 11.4%. vs. 62.4 ± 16.1% p < 0.001). This objective increase in knowledge was in good agreement with participant self-assessments (76.4 ± 12.6% vs. 81.8 ± 11.4%). The quality of the course received good to very good scores, ranging from 1.8 ± 0.7 for speed of presentation to 1.4 ± 0.5 for lecturer competence. The score for overall course quality was 1.4 ± 0.6. Conclusion: A relatively short cardiac CT course can significantly improve the quantifiable knowledge of participants. The overall quality of the course was rated as very good. (orig.)

  10. Water Resource Inventory and Assessment - Flow Map Poster: Ankeny National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This flow map depicts the flow and control of water on Ankeny National Wildlife Refuge. It was produced as part of the Water Resource Inventory and Assessment...

  11. Pre-pregnancy risk assessment and counselling of the cardiac patient

    NARCIS (Netherlands)

    Pieper, P. G.

    2011-01-01

    Pregnant women with heart disease often have an increased risk of maternal cardiovascular and offspring complications. The magnitude of these risks varies depending on the type and severity of the underlying disease. Therefore risk assessment should be performed before pregnancy. This can be accompl

  12. Morphological and Volumetric Analysis of Left Atrial Appendage and Left Atrium: Cardiac Computed Tomography-Based Reproducibility Assessment

    Science.gov (United States)

    Taina, Mikko; Korhonen, Miika; Haataja, Mika; Muuronen, Antti; Arponen, Otso; Hedman, Marja; Jäkälä, Pekka; Sipola, Petri; Mustonen, Pirjo; Vanninen, Ritva

    2014-01-01

    Objectives Left atrial appendage (LAA) dilatation and morphology may influence an individual's risk for intracardiac thrombi and ischemic stroke. LAA size and morphology can be evaluated using cardiac computed tomography (cCT). The present study evaluated the reproducibility of LAA volume and morphology assessments. Methods A total of 149 patients (47 females; mean age 60.9±10.6 years) with suspected cardioembolic stroke/transient ischemic attack underwent cCT. Image quality was rated based on four categories. Ten patients were selected from each image quality category (N = 40) for volumetric reproducibility analysis by two individual readers. LAA and left atrium (LA) volume were measured in both two-chamber (2CV) and transversal view (TV) orientation. Intertechnique reproducibility was assessed between 2CV and TV (200 measurement pairs). LAA morphology (A = Cactus, B = ChickenWing, C = WindSock, D = CauliFlower), LAA opening height, number of LAA lobes, trabeculation, and orientation of the LAA tip was analysed in all study subjects by three individual readers (447 interobserver measurement pairs). The reproducibility of volume measurements was assessed by intra-class correlation (ICC) and the reproducibility of LAA morphology assessments by Cohen's kappa. Results The intra-observer and interobserver reproducibility of LAA and LA volume measurements was excellent (ICCs>0.9). The LAA (ICC = 0.954) and LA (ICC = 0.945) volume measurements were comparable between 2CV and TV. Morphological classification (ĸ = 0.24) and assessments of LAA opening height (ĸ = 0.1), number of LAA lobes (ĸ = 0.16), trabeculation (ĸ = 0.15), and orientation of the LAA tip (ĸ = 0.37) was only slightly to fairly reproducible. Conclusions LA and LAA volume measurements on cCT provide excellent reproducibility, whereas visual assessment of LAA morphological features is challenging and results in unsatisfactory agreement between readers

  13. Morphological and volumetric analysis of left atrial appendage and left atrium: cardiac computed tomography-based reproducibility assessment.

    Directory of Open Access Journals (Sweden)

    Mikko Taina

    Full Text Available OBJECTIVES: Left atrial appendage (LAA dilatation and morphology may influence an individual's risk for intracardiac thrombi and ischemic stroke. LAA size and morphology can be evaluated using cardiac computed tomography (cCT. The present study evaluated the reproducibility of LAA volume and morphology assessments. METHODS: A total of 149 patients (47 females; mean age 60.9±10.6 years with suspected cardioembolic stroke/transient ischemic attack underwent cCT. Image quality was rated based on four categories. Ten patients were selected from each image quality category (N = 40 for volumetric reproducibility analysis by two individual readers. LAA and left atrium (LA volume were measured in both two-chamber (2CV and transversal view (TV orientation. Intertechnique reproducibility was assessed between 2CV and TV (200 measurement pairs. LAA morphology (A = Cactus, B = ChickenWing, C = WindSock, D = CauliFlower, LAA opening height, number of LAA lobes, trabeculation, and orientation of the LAA tip was analysed in all study subjects by three individual readers (447 interobserver measurement pairs. The reproducibility of volume measurements was assessed by intra-class correlation (ICC and the reproducibility of LAA morphology assessments by Cohen's kappa. RESULTS: The intra-observer and interobserver reproducibility of LAA and LA volume measurements was excellent (ICCs>0.9. The LAA (ICC = 0.954 and LA (ICC = 0.945 volume measurements were comparable between 2CV and TV. Morphological classification (ĸ = 0.24 and assessments of LAA opening height (ĸ = 0.1, number of LAA lobes (ĸ = 0.16, trabeculation (ĸ = 0.15, and orientation of the LAA tip (ĸ = 0.37 was only slightly to fairly reproducible. CONCLUSIONS: LA and LAA volume measurements on cCT provide excellent reproducibility, whereas visual assessment of LAA morphological features is challenging and results in unsatisfactory agreement between readers.

  14. Diagnostic performance of cardiac imaging methods to diagnose ischaemia-causing coronary artery disease when directly compared with fractional flow reserve as a reference standard

    DEFF Research Database (Denmark)

    Danad, Ibrahim; Szymonifka, Jackie; Twisk, Jos W R; Norgaard, Bjarne L; Zarins, Christopher K; Knaapen, Paul; Min, James K

    2016-01-01

    diagnosis of ischaemic coronary artery disease (CAD) were included. Twenty-three articles reporting on 3788 patients and 5323 vessels were identified. Meta-analysis was performed for pooled sensitivity, specificity, likelihood ratios (LR), diagnostic odds ratio, and summary receiver operating characteristic......-vessel specificity was highest for MRI (85%, 79-89), FFRCT (78%: 78-81), and SPECT (75%: 69-80), whereas ICA (66%: 64-68) and CCTA (58%: 55-61) yielded a lower specificity. CONCLUSIONS: In this meta-analysis comparing cardiac imaging methods directly to FFR, MRI had the highest performance for diagnosis of ischaemia......AIMS: The aim of this study was to determine the diagnostic performance of single-photon emission computed tomography (SPECT), stress echocardiography (SE), invasive coronary angiography (ICA), coronary computed tomography angiography (CCTA), fractional flow reserve (FFR) derived from CCTA (FFRCT...

  15. China Patient-centered Evaluative Assessment of Cardiac Events Prospective Study of Acute Myocardial Infarction:Study Design

    Institute of Scientific and Technical Information of China (English)

    Jing Li; Rachel P Dreyer; Xi Li; Xue Du; Nicholas S Downing; Li Li; Hai-Bo Zhang

    2016-01-01

    Background: Despite the rapid growth in the incidence of acute myocardial infarction (AMI) in China, there is limited information about patients' experiences after AMI hospitalization, especially on long-term adverse events and patient-reported outcomes (PROs).Methods: The China Patient-centered Evaluative Assessment of Cardiac Events (PEACE)-Prospective AMI Study will enroll 4000 consecutive AMI patients from 53 diverse hospitals across China and follow them longitudinally for 12 months to document their treatment, recovery, and outcomes.Details of patients' medical history, treatment, and in-hospital outcomes are abstracted from medical charts.Comprehensive baseline interviews are being conducted to characterize patient demographics, risk factors, presentation, and healthcare utilization.As part of these interviews, validated instruments are administered to measure PROs, including quality of life, symptoms, mood, cognition, and sexual activity.Follow-up interviews, measuring PROs, medication adherence, risk factor control, and collecting hospitalization events are conducted at 1, 6, and 12 months after discharge.Supporting documents for potential outcomes are collected for adjudication by clinicians at the National Coordinating Center.Blood and urine samples are also obtained at baseline, 1-and 12-month follow-up.In addition, we are conducting a survey of participating hospitals to characterize their organizational characteristics.Conclusion: The China PEACE-Prospective AMI study will be uniquely positioned to generate new information regarding patient's experiences and outcomes after AMI in China and serve as a foundation for quality improvement activities.

  16. Bleeding risk assessment in patients undergoing elective cardiac surgery using ROTEM(®) platelet and Multiplate(®) impedance aggregometry.

    Science.gov (United States)

    Petricevic, M; Konosic, S; Biocina, B; Dirkmann, D; White, A; Mihaljevic, M Z; Ivancan, V; Konosic, L; Svetina, L; Görlinger, K

    2016-06-01

    Impaired platelet function is a major risk factor for peri-operative bleeding and transfusion. This prospective, observational study enrolled 101 consecutive patients undergoing elective cardiac surgery with cardiopulmonary bypass. Platelet function was assessed by two whole blood impedance aggregometers (ROTEM(®) platelet and Multiplate(®) ), using three different activators (arachidonic acid, adenosine diphosphate and thrombin receptor-activating peptide-6), at three peri-operative time points (before anaesthesia, after aortic declamping and 5-10 min after protamine administration). Platelet function was impaired over the time-course in all assays. Results after protamine administration demonstrated the best correlation with postoperative chest tube drainage. Patients with a chest tube drainage exceeding the 75th percentile of the entire study population, during the first 24 postoperative hours, were characterised to have excessive bleeding. Both devices provided similar predictability for postoperative chest tube drainage and red blood cell transfusion requirements. The latter was associated with the degree of platelet inhibition and the number of pathways inhibited determined respective cut-off values. PMID:26763378

  17. Assessing Late Cardiopulmonary Function in Patients with Repaired Tetralogy of Fallot Using Exercise Cardiopulmonary Function Test and Cardiac Magnetic Resonance

    Science.gov (United States)

    Yang, Ming-Chun; Chen, Chun-An; Chiu, Hsin-Hui; Chen, Ssu-Yuan; Wang, Jou-Kou; Lin, Ming-Tai; Chiu, Shuenn-Nan; Lu, Chun-Wei; Huang, Shu-Chien; Wu, Mei-Hwan

    2015-01-01

    Background Patients with repaired tetralogy of Fallot (TOF) usually experience progressive right ventricle (RV) dysfunction due to pulmonary regurgitation (PR). This could further worsen the cardiopulmonary function. This study aimed to compare the changes in patient exercise cardiopulmonary test and cardiac magnetic resonance imaging, and consider the implication of these changes. Methods Our study examined repaired TOF patients who underwent cardiopulmonary exercise test (CPET) to obtain maximal (peak oxygen consumption, peak VO2) and submaximal parameters (oxygen uptake efficiency plateau, oxygen uptake efficiency plateau (OUEP), and ratio of minute ventilation to carbon dioxide production, VE/VCO2 slope). Additionally, the hemodynamic status was assessed by using cardiac magnetic resonance. Criteria for exclusion included TOF patients with pulmonary atresia, atrioventricular septal defect, or absence of pulmonary valve syndrome. Results We enrolled 158 patients whose mean age at repair was 7.8 ± 9.1 years (range 0.1-49.2 years) and the mean patient age at CPET was 29.5 ± 12.2 years (range 7.0-57.0 years). Severe PR (PR fraction ≥ 40%) in 53 patients, moderate in 55, and mild (PR fraction 163 ml/m2. The mean left ventricular ejection fraction (LVEF) was 63 ± 8%, left ventricular end-diastolic volume index (LVEDVi) was 65 ± 12 ml/m2, and LVESVi was 25 ± 14 ml/m2. CPET revealed significantly decreased peak VO2 (68.5 ± 14.4% of predicted), and fair OUEP (90.3 ± 14.1% of predicted) and VE/VCO2 slope (27.1 ± 5.3). PR fraction and age at repair were negatively correlated with maximal and submaximal exercise indicators (peak VO2 and OUEP). Left ventricular (LV) function and size were positively correlated with peak VO2 and OUEP. Conclusions The results of CPET showed that patients with repaired TOF had a low maximal exercise capacity (peak VO2), but a fair submaximal exercise capacity (OUEP and VE/VCO2 slope), suggesting limited exercise capability in high

  18. Use of I-123 MIBG cardiac scintigraphy to assess the impact of carvedilol on cardiac adrenergic neuronal function in childhood dilated cardiomyopathy; Interet de la scintigraphie cardiaque a l'I-123 MIBG pour evaluer l'impact du carvedilol sur la fonction neuronale adrenergique cardiaque dans les myocardiopathies dilatees de l'enfant

    Energy Technology Data Exchange (ETDEWEB)

    Maunoury, C. [Hopital Europeen Georges Pompidou (HEGP), Dept. de Physiologie et Radio-Isotopes, 75 - Paris (France); Acar, P. [Centre Hospitalier Universitaire, Service de Cardiologie Pediatrique, Hopital des Enfants, 31 - Toulouse (France); Sidi, D. [Centre Hospitalier Universitaire Necker-Enfants-Malades, 75 - Paris (France)

    2006-04-15

    I-123 MIBG cardiac scintigraphy is a useful tool to assess cardiac adrenergic neuronal function, which is impaired in children with dilated cardiomyopathy (DCM). In adults with DCM, long-term treatment with carvedilol improves both cardiac adrenergic neuronal function and left ventricular function. The aim of this prospective study was to evaluate the impact of carvedilol on cardiac adrenergic neuronal function and on left ventricular function in seventeen patients (11 female, 6 male, mean age 39 {+-} 57 months, range 1 - 168 months) with DCM. All patients underwent I-123 MIBG cardiac scintigraphy and equilibrium radio-nuclide angiography before and after a 6 month period of carvedilol therapy. A static anterior view of the chest was acquired 4 hours after intravenous injection of 20 to 75 MBq of I-123 MIBG. Cardiac neuronal uptake of I-123 MIBG was measured using the heart to mediastinum count ratio (HMR). Radionuclide left ventricular ejection fraction (LVEF) was assessed following a standard protocol. There was no major cardiac events (death or transplantation) during the follow-up period. I-123 MIBG cardiac uptake and left ventricular function respectively increased by 38% and 65% after 6 months of treatment with carvedilol (HMR 223 {+-} 49% vs 162 {+-} 26%, p < 0.0001 and LVEF = 43 {+-} 17% vs 26 {+-} 11%, p < 0.0001). Carvedilol can improve cardiac adrenergic neuronal function and left ventricular function in children with DCM. Further studies are needed to assess the relationship between improvement in I-123 MIBG cardiac uptake and the beneficial effects of carvedilol on morbidity and mortality. (authors)

  19. Intracranial flow of cerebrospinal fluid

    International Nuclear Information System (INIS)

    This paper reports cerebrospinal fluid (CSF) flow in the third ventricle, aqueduct, fourth ventricle, basal cisterns, and subarachnoid spaces at the cervical-medullary junction evaluated in 25 patients and 10 normal volunteers. Information was acquired on 1.5-T magnet with a cardiac-gated, single-section, gradient-echo technique and displayed via closed-loop cine imaging. Qualitative assessment of flow patterns via magnitude reconstruction was correlated with quantitative data generated via phase reconstruction. Normal patterns of CSF flow were established. Pathologic changes involving these pathways altered the flow patterns, either causing increased turbulence and flow of CSF or decreasing the expected flow

  20. Assessment Of Nurses Performance During Cardiopulmonary Resuscitation In Intensive Care Unit And Cardiac Care Unit At The Alexandria Main University Hospital.

    Directory of Open Access Journals (Sweden)

    Dr. Nagla Hamdi Kamal Khalil El- Meanawi

    2015-08-01

    Full Text Available Abstract Background Cardiopulmonary resuscitation one of the most emergency management the nurse has a pivotal role and should be highly qualified in performing these procedures. The aim of the study is to assess performance of nurses during Cardio pulmonary resuscitation for patient with cardiac arrest In Intensive Care Unit and Cardiac Care Unit at the Alexandria main university hospital. To answer the question what are the most common area of satisfactory and area of neglection in nurses performance during Cardio Pulmonary Resuscitation. The sample consists of 53 staff nurses working in Intensive care unit amp cardiac care unit at Alexandria main university hospital. The tools of data collection were structured of questionnaire sheet and observational cheek list. The results showed that unsatisfactory performance between nurses in both units. The study concluded that all nurses need to improve their performance during cardiopulmonary resuscitation for patient with cardiac arrest it is crucial for nursing staff to participate in CPR courses in order to refresh and update their theoretical knowledge and performance skills and consequently to improve the safety and effectiveness of care. The study recommended that continuous evaluation of nurses knowledge and performance is essential the optimal frequency with which CPR training should be implemented at least every 6 months in order to avoid deterioration in nurses CPR knowledge and skills.

  1. 7 Tesla (T) human cardiovascular magnetic resonance imaging using FLASH and SSFP to assess cardiac function: validation against 1.5 T and 3 T

    OpenAIRE

    Suttie, J. J.; DelaBarre, L; Pitcher, A.; van de Moortele, P. F.; Dass, S; Snyder, C. J.; Francis, J M; Metzger, G. J.; Weale, P.; Ugurbil, K; Neubauer, S.; Robson, M; Vaughan, T

    2011-01-01

    We report the first comparison of cardiovascular magnetic resonance imaging (CMR) at 1.5 T, 3 T and 7 T field strengths using steady state free precession (SSFP) and fast low angle shot (FLASH) cine sequences. Cardiac volumes and mass measurements were assessed for feasibility, reproducibility and validity at each given field strength using FLASH and SSFP sequences. Ten healthy volunteers underwent retrospectively electrocardiogram (ECG) gated CMR at 1.5 T, 3 T and 7 T using FLASH and SSFP se...

  2. Anti-addiction drug ibogaine inhibits voltage-gated ionic currents: A study to assess the drug's cardiac ion channel profile ☆

    OpenAIRE

    Koenig, Xaver; Kovar, Michael; Rubi, Lena; Mike, Agnes K.; Lukacs, Peter; Gawali, Vaibhavkumar S; Todt, Hannes; Hilber, Karlheinz; Sandtner, Walter

    2013-01-01

    The plant alkaloid ibogaine has promising anti-addictive properties. Albeit not licenced as a therapeutic drug, and despite hints that ibogaine may perturb the heart rhythm, this alkaloid is used to treat drug addicts. We have recently reported that ibogaine inhibits human ERG (hERG) potassium channels at concentrations similar to the drugs affinity for several of its known brain targets. Thereby the drug may disturb the heart's electrophysiology. Here, to assess the drug's cardiac ion channe...

  3. Model-based analysis of ecg-gated cardiac pet images to assess left ventricular volume and contractile function

    International Nuclear Information System (INIS)

    ESV, and 210 ± 82 and 158 ± 67 for EDV, and EF was 34 ± 10 % and 37 ± 17 % by PET and echocardiography. A significant correlation was observed between two methods for calculation of ESV (r = 0.93, SEE = 28.1, p < 0.003), and EDV (r = 0.87, SEE = 44.8, p < 0.012) and EF (r = 0.89, SEE = 7.4, p < 0.0001). In conclusion, the model-based analysis of gated cardiac PET images seems to offer a novel method for a near simultaneous assessment of myocardial perfusion, metabolism and contractile function. (author)

  4. Measurement and Assessment of Flow Quality in Wind Tunnels Project

    Data.gov (United States)

    National Aeronautics and Space Administration — New wind tunnel flow quality test and analysis procedures have been developed and will be used to establish standardized turbulent flow quality measurement...

  5. Remote detection of mental workload changes using cardiac parameters assessed with a low-cost webcam.

    Science.gov (United States)

    Bousefsaf, Frédéric; Maaoui, Choubeila; Pruski, Alain

    2014-10-01

    We introduce a new framework for detecting mental workload changes using video frames obtained from a low-cost webcam. Image processing in addition to a continuous wavelet transform filtering method were developed and applied to remove major artifacts and trends on raw webcam photoplethysmographic signals. The measurements are performed on human faces. To induce stress, we have employed a computerized and interactive Stroop color word test on a set composed by twelve participants. The electrodermal activity of the participants was recorded and compared to the mental workload curve assessed by merging two parameters derived from the pulse rate variability and photoplethysmographic amplitude fluctuations, which reflect peripheral vasoconstriction changes. The results exhibit strong correlation between the two measurement techniques. This study offers further support for the applicability of mental workload detection by remote and low-cost means, providing an alternative to conventional contact techniques. PMID:25150821

  6. Assessment of Liver Fibrosis Using Fast Strain-Encoded (FSENC) MRI Driven by Inherent Cardiac Motion

    Science.gov (United States)

    Harouni, Ahmed A.; Gharib, Ahmed M.; Osman, Nael F.; Morse, Caryn; Heller, Theo; Abd-Elmoniem, Khaled Z.

    2014-01-01

    Purpose An external driver-free MRI method for assessment of liver fibrosis offers a promising non-invasive tool for diagnosis and monitoring of liver disease. Lately, the heart’s intrinsic motion and MR tagging have been utilized for the quantification of liver strain. However, MR tagging requires multiple breath-hold acquisitions and substantial post-processing. This work proposes a fast strain-encoded (FSENC) MRI methodology to measure the peak strain (Sp) in the liver’s left lobe, which is in close proximity and caudal to the heart. Additionally, a new method is introduced to measure heart-induced shear wave velocity (SWV) inside the liver. Methods Phantom and in-vivo experiments (11 healthy subjects, and 11 patients with liver fibrosis) were conducted. Reproducibility experiments were performed in seven healthy subjects. Results Peak liver strain Sp significantly decreased in fibrotic liver compared healthy liver (6.46%±2.27% vs. 12.49%±1.76%, P<0.05). Heart-induced SWV significantly increased in patients compared to healthy subjects (0.15±0.04 m/s vs. 0.63±0.32 m/s, P<0.05). Reproducibility analysis yielded no significant difference in Sp (P=0.47) or SWV (P=0.56). Conclusion Accelerated external driver-free noninvasive assessment of left liver lobe strain and shear wave velocity is feasible using strain-encoded MRI. The two measures significantly separate healthy subjects from patients with fibrotic liver. PMID:25081734

  7. Assessment of myocardial damage in hypertrophic cardiomyopathy using cardiac enzymes, myosin light chain and myocardial scintigraphy

    International Nuclear Information System (INIS)

    To assess myocardial damage in hypertrophic cardiomyopathy (HCM), CPK-MB, %LDH 1, myoglobin (Mb), and myosin light chain (MLC) were determined in 45 HCM patients. Of these patients, 10 also underwent Tl-201 myocardial scintigraphy and In-111-antimyosin antibody (In-111 Fab-DTPA)(In-AM) myocardial scintigraphy. MLC was 0.56±0.55 ng/ml. An increase in CPK-MB, %LDH 1, and Mb was seen in 6 (14%), 19 (44%), and 7 (18%) patients, respectively. There was no correlation between MLC and any of CPK-MB, %LDH1 or Mb. Perfusion defects were seen on Tl-201 myocardial scintigrams in 4 patients. All of these patients had diffuse tracer uptake on In-AM myocardial scintigrams. The degree of In-AM uptake was not correlated with MLC; however, of 4 patients with intense In-AM uptake, 3 had perfusion defects on Tl-201 myocardial scintigrams and decreased left ventricular function. In 3 patients in whom CPK-MB and %LDH 1 were increased but MLC was not increased, diffuse tracer uptake was seen on In-AM myocardial scintigrams. Because diffuse uptake of In-AM was seen in spite of the lack of increased MLC, In-111-Fab-DTPA is likely to be incorporated by the myocardial damaged cells, as well as necrotic cells. HCM seems to be associated with a high likelihood of myocardial damage. Integrated assessment of myocardial damage is required, including an increase of MLC, CPK-MB, %LDH 1, and Mb, perfusion defects on Tl-201 scintigrams, and tracer uptake on In-AM scintigrams. (N.K.)

  8. A dynamic thorax phantom for the assessment of cardiac and respiratory motion correction in PET/MRI: A preliminary evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Fieseler, Michael, E-mail: michael.fieseler@uni-muenster.de [European Institute for Molecular Imaging, University of Münster, Mendelstrasse 11, 48149 Münster (Germany); Department of Computer Science, University of Münster, Einsteinstrasse 62, 48149 Münster (Germany); Kugel, Harald [Department of Clinical Radiology, University Hospital of Münster, Albert-Schweitzer-Campus 1, 48149 Münster (Germany); Gigengack, Fabian [European Institute for Molecular Imaging, University of Münster, Mendelstrasse 11, 48149 Münster (Germany); Department of Computer Science, University of Münster, Einsteinstrasse 62, 48149 Münster (Germany); Kösters, Thomas; Büther, Florian [European Institute for Molecular Imaging, University of Münster, Mendelstrasse 11, 48149 Münster (Germany); Quick, Harald H. [Institute of Medical Physics, University of Erlangen-Nürnberg, Henkestrasse 91, 91052 Erlangen (Germany); Faber, Cornelius [Department of Clinical Radiology, University Hospital of Münster, Albert-Schweitzer-Campus 1, 48149 Münster (Germany); Jiang, Xiaoyi [Department of Computer Science, University of Münster, Einsteinstrasse 62, 48149 Münster (Germany); Schäfers, Klaus P. [European Institute for Molecular Imaging, University of Münster, Mendelstrasse 11, 48149 Münster (Germany)

    2013-02-21

    Respiratory and cardiac motion are a known source of image degradation and quantification impairment in positron emission tomography (PET). In this study we use near-realistic PET/MRI data acquired using a custom-built human torso phantom capable of simulating respiratory and cardiac motion. We demonstrate that a significant reduction in motion-induced artifacts in PET data is possible using MR-derived motion estimates.

  9. A dynamic thorax phantom for the assessment of cardiac and respiratory motion correction in PET/MRI: A preliminary evaluation

    Science.gov (United States)

    Fieseler, Michael; Kugel, Harald; Gigengack, Fabian; Kösters, Thomas; Büther, Florian; Quick, Harald H.; Faber, Cornelius; Jiang, Xiaoyi; Schäfers, Klaus P.

    2013-02-01

    Respiratory and cardiac motion are a known source of image degradation and quantification impairment in positron emission tomography (PET). In this study we use near-realistic PET/MRI data acquired using a custom-built human torso phantom capable of simulating respiratory and cardiac motion. We demonstrate that a significant reduction in motion-induced artifacts in PET data is possible using MR-derived motion estimates.

  10. Evaluation of cardiac blood blow, metabolism and sympathetic nerve function in patients with cardiac failure using PET and SPECT. Prognostic diagnosis based on the analysis of aggravating factors of the disease

    International Nuclear Information System (INIS)

    Focusing on the failure of energy metabolism, which is assumed to be attributed to the cardiac muscle disorder of a patient with cardiac failure, the characteristics and diagnostic significance of the metabolic disorders of cadiac muscles were investigated in those patients. The diagnostic efficacy of β-methyl iodophenyl pentadecanoic acid (BMIPP) which is a imaging agent for lipid metabolism in the cardiac muscle was assessed in the clinical states of cardiac failure due to pulmonary hypertension. Even if there was a considerable increase in the mean pulmonary arterial pressure (mPAP), the initial accumulation of BMIPP linearly increased, similarly to the increase in the accumulation of MIBI, a blood flow agent. The initial accumulation of BMIPP was thought to reflect a thicken cardiac muscle and/or increased blood flow. Also, its washing-out rate was suggested to be usable as an clinical indicator to estimate the loading of ventricular pressure. (M.N.)

  11. Evaluation of cardiac blood blow, metabolism and sympathetic nerve function in patients with cardiac failure using PET and SPECT. Prognostic diagnosis based on the analysis of aggravating factors of the disease

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, Yoshio; Shimozu, Junko; Yasumura, Yoshio; Nagatani, Kenzo; Miyatake, Kunio [National Cardiovascular Center, Suita, Osaka (Japan)

    1998-02-01

    Focusing on the failure of energy metabolism, which is assumed to be attributed to the cardiac muscle disorder of a patient with cardiac failure, the characteristics and diagnostic significance of the metabolic disorders of cadiac muscles were investigated in those patients. The diagnostic efficacy of {beta}-methyl iodophenyl pentadecanoic acid (BMIPP) which is a imaging agent for lipid metabolism in the cardiac muscle was assessed in the clinical states of cardiac failure due to pulmonary hypertension. Even if there was a considerable increase in the mean pulmonary arterial pressure (mPAP), the initial accumulation of BMIPP linearly increased, similarly to the increase in the accumulation of MIBI, a blood flow agent. The initial accumulation of BMIPP was thought to reflect a thicken cardiac muscle and/or increased blood flow. Also, its washing-out rate was suggested to be usable as an clinical indicator to estimate the loading of ventricular pressure. (M.N.)

  12. Assessing Cardiac Injury in Mice With Dual Energy-MicroCT, 4D-MicroCT, and MicroSPECT Imaging After Partial Heart Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang-Lung; Min, Hooney [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Befera, Nicholas; Clark, Darin; Qi, Yi [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States); Das, Shiva [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Johnson, G. Allan; Badea, Cristian T. [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States); Kirsch, David G., E-mail: david.kirsch@duke.edu [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina (United States)

    2014-03-01

    Purpose: To develop a mouse model of cardiac injury after partial heart irradiation (PHI) and to test whether dual energy (DE)-microCT and 4-dimensional (4D)-microCT can be used to assess cardiac injury after PHI to complement myocardial perfusion imaging using micro-single photon emission computed tomography (SPECT). Methods and Materials: To study cardiac injury from tangent field irradiation in mice, we used a small-field biological irradiator to deliver a single dose of 12 Gy x-rays to approximately one-third of the left ventricle (LV) of Tie2Cre; p53{sup FL/+} and Tie2Cre; p53{sup FL/−} mice, where 1 or both alleles of p53 are deleted in endothelial cells. Four and 8 weeks after irradiation, mice were injected with gold and iodinated nanoparticle-based contrast agents, and imaged with DE-microCT and 4D-microCT to evaluate myocardial vascular permeability and cardiac function, respectively. Additionally, the same mice were imaged with microSPECT to assess myocardial perfusion. Results: After PHI with tangent fields, DE-microCT scans showed a time-dependent increase in accumulation of gold nanoparticles (AuNp) in the myocardium of Tie2Cre; p53{sup FL/−} mice. In Tie2Cre; p53{sup FL/−} mice, extravasation of AuNp was observed within the irradiated LV, whereas in the myocardium of Tie2Cre; p53{sup FL/+} mice, AuNp were restricted to blood vessels. In addition, data from DE-microCT and microSPECT showed a linear correlation (R{sup 2} = 0.97) between the fraction of the LV that accumulated AuNp and the fraction of LV with a perfusion defect. Furthermore, 4D-microCT scans demonstrated that PHI caused a markedly decreased ejection fraction, and higher end-diastolic and end-systolic volumes, to develop in Tie2Cre; p53{sup FL/−} mice, which were associated with compensatory cardiac hypertrophy of the heart that was not irradiated. Conclusions: Our results show that DE-microCT and 4D-microCT with nanoparticle-based contrast agents are novel imaging approaches

  13. Assessing Cardiac Injury in Mice With Dual Energy-MicroCT, 4D-MicroCT, and MicroSPECT Imaging After Partial Heart Irradiation

    International Nuclear Information System (INIS)

    Purpose: To develop a mouse model of cardiac injury after partial heart irradiation (PHI) and to test whether dual energy (DE)-microCT and 4-dimensional (4D)-microCT can be used to assess cardiac injury after PHI to complement myocardial perfusion imaging using micro-single photon emission computed tomography (SPECT). Methods and Materials: To study cardiac injury from tangent field irradiation in mice, we used a small-field biological irradiator to deliver a single dose of 12 Gy x-rays to approximately one-third of the left ventricle (LV) of Tie2Cre; p53FL/+ and Tie2Cre; p53FL/− mice, where 1 or both alleles of p53 are deleted in endothelial cells. Four and 8 weeks after irradiation, mice were injected with gold and iodinated nanoparticle-based contrast agents, and imaged with DE-microCT and 4D-microCT to evaluate myocardial vascular permeability and cardiac function, respectively. Additionally, the same mice were imaged with microSPECT to assess myocardial perfusion. Results: After PHI with tangent fields, DE-microCT scans showed a time-dependent increase in accumulation of gold nanoparticles (AuNp) in the myocardium of Tie2Cre; p53FL/− mice. In Tie2Cre; p53FL/− mice, extravasation of AuNp was observed within the irradiated LV, whereas in the myocardium of Tie2Cre; p53FL/+ mice, AuNp were restricted to blood vessels. In addition, data from DE-microCT and microSPECT showed a linear correlation (R2 = 0.97) between the fraction of the LV that accumulated AuNp and the fraction of LV with a perfusion defect. Furthermore, 4D-microCT scans demonstrated that PHI caused a markedly decreased ejection fraction, and higher end-diastolic and end-systolic volumes, to develop in Tie2Cre; p53FL/− mice, which were associated with compensatory cardiac hypertrophy of the heart that was not irradiated. Conclusions: Our results show that DE-microCT and 4D-microCT with nanoparticle-based contrast agents are novel imaging approaches complementary to microSPECT for

  14. Assessments of Coronary Artery Visibility and Radiation Dose in Infants with Congenital Heart Disease on Cardiac 128-slice CT and on Cardiac 64-slice CT.

    Science.gov (United States)

    Cui, Y; Huang, M; Zheng, J; Li, J; Liu, H; Liang, C

    2016-01-01

    The aim of this study was to compare the coronary artery visibility and radiation dose in infants with CHD on cardiac 128-slice CT and on cardiac 64-slice CT. The images of 200 patients were analyzed in this study, 100 patients were selected randomly from a group of 789 infants (ECG-triggered axial scan, and 100 were selected randomly from 911 infants with CHD undergoing 64-slice CT retrospective ECG-gated spiral scan. The visibility of coronary artery segments was graded on a four-point scale. The coronary arteries were considered to be detected or visible when grade was 2 or higher. The visibility of the coronary artery segments and the radiation dose was compared between the two groups. Except for the rate of LM (96 vs. 99%), the detection rates of the total, LAD, LCX, RCA, and the proximal segment of the RCA in the 256-slice CT group were significantly higher than those in the 64-slice CT group (51.7, 53.33, 33.67, 53.33, and 99 vs. 34.8, 34.33, 18, 30.67, and 75%, respectively). The counts of visibility score (4/3/2/1) for the LM and the proximal segment of the RCA were 62/22/12/4 and 56/20/17/7, respectively, in the 128-slice CT group and 17/42/30/1 and 9/30/38/25, respectively, in the 64-slice CT group. There were significant differences, especially for score 4 and 3, between the two groups. The radiation dose in the 128-slice CT group was significantly decreased than those in the 64-slice CT group (CTDIvol 1.88 ± 0.51 vs. 5.61 ± 0.63 mGy; SSDE 4.48 ± 1.15 vs. 13.97 ± 1.52 mGy; effective radiation dose 1.36 ± 0.44 vs. 4.06 ± 0.7 mSv). With reduced radiation dose, the visibility of the coronary artery in infants with CHD via prospective ECG-triggered mode on a 128-slice CT is superior to that of the 64-slice CT using retrospective ECG-gated spiral mode. PMID:26271472

  15. Cardiac vectors in the healthy human fetus: developmental changes assessed by magnetocardiography and realistic approximations of the volume conductor

    International Nuclear Information System (INIS)

    This study sought to characterize the developmental changes of three measures used to describe the morphology of the fetal cardiac vector: QRS peak-amplitude, QRS duration and QRS time-amplitude integral. To achieve this objective, we rely on a recently developed methodology for fetal cardiac vector estimation, using multichannel fetal magnetocardiographic (fMCG) recordings and realistic approximations of the volume conductors obtained from free-hand ultrasound imaging. fMCG recordings and 3D ultrasound images were obtained from 23 healthy, uncomplicated pregnancies for a total of 77 recordings performed at gestational ages between 22 and 37 weeks. We report the developmental changes of the cardiac vector parameters with respect to gestational age and estimated fetal weight, as well as their dependence on the estimated ventricular mass derived from cardiac dimensions measured with M-mode ultrasound. The normative values can be used along with the cardiac time intervals reported by previous fMCG studies to assist future clinical studies investigating conditions that affect fetal cardiac function. (paper)

  16. Assessment of cardiac function by an ambulatory ventricular function monitor (VEST), (2)

    International Nuclear Information System (INIS)

    To assess incidence of ischemic episodes in patients with coronary artery disease (CAD), left ventricular function and electrocardiogram (ECG) were continuously monitored by an ambulatory ventricular function monitor (VEST) during daily activities for a mean of 2.1 hours in 13 patients with CAD. Nine were patients with unstable angina. This VEST detected 20 episodes of transient decrease in ejection fraction ( ≥ 6 % below the baseline) in 8 patients. Five were symptomatic and 15 were symptom free. Among 5 symptomatic episodes, four were typical ischemic ones accompanied with ST segment depression on ECG. Among 15 asymptomatic episodes, 4 were associated with ST depression, which was highly suggestive of silent ischemia. However, 11 episodes of transient decrease in ejection fraction were not accompanied with either symptoms or ECG changes. On the other hand, the VEST detected 10 periods of ST depression, among which two were not associated with transient decrease in ejection fraction. We conclude that monitoring both ventricular function and ECG by the VEST is valuable for detecting and evaluating various episodes in patients with CAD. (author)

  17. Assessing temporal and spatial alterations of flow regimes in the regulated Huai River Basin, China

    Science.gov (United States)

    Zhang, Yongyong; Zhai, Xiaoyan; Shao, Quanxi; Yan, Ziqi

    2015-10-01

    The assessment of flow regime alterations is fundamental in understanding the potential impact of reservoirs and other water infrastructures on aquatic ecosystems and biota. Previously used methods to classify flow regimes have not captured temporal changes between unregulated and regulated flow regimes at individual stations. In this study, a combination of hierarchical classification and trend analysis was used to assess spatial and temporal flow regime alterations in the Huai River Basin, China. Two categories of flow regime indices were selected to characterize the impacts of reservoir and sluice regulation, including the basic flow indices for mean variation, and the cumulative variation indices for long-term alteration. The overall impact of reservoirs and sluices on flow regime included the decrease of high flow magnitudes but the increase of low flow magnitudes through time. Moreover, on average, the flow variability, and the high and low flow frequencies were reduced, while their durations were increased. Reservoirs had a greater impact on flow regimes than sluices. The flow regimes at 18 of 30 stations were altered significantly from a pre-regulation condition and were divided into three main types of alteration corresponding to operational rules of reservoirs and sluices. From a management perspective, water projects in China should address the environmental flow requirements of the rivers, particularly in terms of the hydrologic indices affected mostly by reservoirs and sluices. This study will promote the application of flow regime classification and river restoration in highly regulated basins in China.

  18. Assessment of the Efficacy of Pulsed Biphasic Defibrillation Shocks for Treatment of Out-of-hospital Cardiac Arrest

    Directory of Open Access Journals (Sweden)

    Jean-Philippe Didon

    2008-10-01

    Full Text Available This study evaluates the efficacy of a Pulsed Biphasic Waveform (PBW for treatment of out-of-hospital cardiac arrest (OHCA patients in ventricular fibrillation (VF. Large database (2001-2006, collected with automated external defibrillators (AED, (FRED®, Schiller Medical SAS, France, is processed.In Study1 we compared the defibrillation efficacy of two energy stacks (90-130-180 J vs. (130-130-180 J in 248 OHCA VF patients. The analysis of the first shock PBW efficacy proves that energies as low as 90 J are able to terminate VF in a large proportion of OHCA patients (77% at 5 s and 69% at 30 s. Although the results show a trend towards the benefit of higher energy PBW with 130 J (86% at 5 s, 73% at 30 s, the difference in shock efficacy does not reach statistical significance. Both PBW energy stacks (90-130-180 J and (130-130-180 J achieve equal success rates of defibrillation. Analysis of the post-shock rhythm after the first shock is also provided.For Study2 of 21 patients with PBW shocks (130-130-180 J, we assessed some attending OHCA circumstances: call-to-shock delay (median 16min, range 11-41 min, phone advices of CPR (67%. About 50% of the patients were admitted alive to hospital, and 19% were discharged from hospital. After the first shock, patients admitted to hospital are more often presenting organized rhythm (OR (27% to 55% than patients not admitted (0% to 10%, with significant difference at 15 s and 30 s. Post-shock VFs appear significantly rare until 15s for patients admitted to hospital (0% to 9% than for patients not admitted to hospital (40% to 50%. Return of OR (ROOR and efficacy to defibrillate VF at 5 s and 15 s with first shock are important markers to predict patient admission to hospital.

  19. Assessing the velocity of the groundwater flow in bedrock fractures

    International Nuclear Information System (INIS)

    Teollisuuden Voima Oy (TVO) is studying the crystalline bedrock in Finland for the final disposal of the spent nuclear fuel from its two reactors in Olkiluoto. Preliminary site investigations for five areas were carried out during 1987-1992. One part of the investigation programme was three-dimensional groundwater flow modelling. The numerical site-specific flow simulations were based on the concept of an equivalent porous continuum. The results include hydraulic head distributions, average groundwater flow rate routes. In this study, a novel approach was developed to evaluate the velocities of the water particles flowing in the fractured bedrock. (17 refs., 15 figs., 5 tabs.)

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

    LENUS (Irish Health Repository)

    O'Donnell, David H

    2012-02-01

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

  1. Anti-addiction drug ibogaine inhibits voltage-gated ionic currents: A study to assess the drug's cardiac ion channel profile

    Energy Technology Data Exchange (ETDEWEB)

    Koenig, Xaver; Kovar, Michael; Rubi, Lena; Mike, Agnes K.; Lukacs, Peter; Gawali, Vaibhavkumar S.; Todt, Hannes [Center for Physiology and Pharmacology, Department of Neurophysiology and -pharmacology, Medical University of Vienna, 1090 Vienna (Austria); Hilber, Karlheinz, E-mail: karlheinz.hilber@meduniwien.ac.at [Center for Physiology and Pharmacology, Department of Neurophysiology and -pharmacology, Medical University of Vienna, 1090 Vienna (Austria); Sandtner, Walter [Center for Physiology and Pharmacology, Institute of Pharmacology, Medical University of Vienna, 1090 Vienna (Austria)

    2013-12-01

    The plant alkaloid ibogaine has promising anti-addictive properties. Albeit not licenced as a therapeutic drug, and despite hints that ibogaine may perturb the heart rhythm, this alkaloid is used to treat drug addicts. We have recently reported that ibogaine inhibits human ERG (hERG) potassium channels at concentrations similar to the drugs affinity for several of its known brain targets. Thereby the drug may disturb the heart's electrophysiology. Here, to assess the drug's cardiac ion channel profile in more detail, we studied the effects of ibogaine and its congener 18-Methoxycoronaridine (18-MC) on various cardiac voltage-gated ion channels. We confirmed that heterologously expressed hERG currents are reduced by ibogaine in low micromolar concentrations. Moreover, at higher concentrations, the drug also reduced human Na{sub v}1.5 sodium and Ca{sub v}1.2 calcium currents. Ion currents were as well reduced by 18-MC, yet with diminished potency. Unexpectedly, although blocking hERG channels, ibogaine did not prolong the action potential (AP) in guinea pig cardiomyocytes at low micromolar concentrations. Higher concentrations (≥ 10 μM) even shortened the AP. These findings can be explained by the drug's calcium channel inhibition, which counteracts the AP-prolonging effect generated by hERG blockade. Implementation of ibogaine's inhibitory effects on human ion channels in a computer model of a ventricular cardiomyocyte, on the other hand, suggested that ibogaine does prolong the AP in the human heart. We conclude that therapeutic concentrations of ibogaine have the propensity to prolong the QT interval of the electrocardiogram in humans. In some cases this may lead to cardiac arrhythmias. - Highlights: • We study effects of anti-addiction drug ibogaine on ionic currents in cardiomyocytes. • We assess the cardiac ion channel profile of ibogaine. • Ibogaine inhibits hERG potassium, sodium and calcium channels. • Ibogaine’s effects on

  2. Anti-addiction drug ibogaine inhibits voltage-gated ionic currents: A study to assess the drug's cardiac ion channel profile

    International Nuclear Information System (INIS)

    The plant alkaloid ibogaine has promising anti-addictive properties. Albeit not licenced as a therapeutic drug, and despite hints that ibogaine may perturb the heart rhythm, this alkaloid is used to treat drug addicts. We have recently reported that ibogaine inhibits human ERG (hERG) potassium channels at concentrations similar to the drugs affinity for several of its known brain targets. Thereby the drug may disturb the heart's electrophysiology. Here, to assess the drug's cardiac ion channel profile in more detail, we studied the effects of ibogaine and its congener 18-Methoxycoronaridine (18-MC) on various cardiac voltage-gated ion channels. We confirmed that heterologously expressed hERG currents are reduced by ibogaine in low micromolar concentrations. Moreover, at higher concentrations, the drug also reduced human Nav1.5 sodium and Cav1.2 calcium currents. Ion currents were as well reduced by 18-MC, yet with diminished potency. Unexpectedly, although blocking hERG channels, ibogaine did not prolong the action potential (AP) in guinea pig cardiomyocytes at low micromolar concentrations. Higher concentrations (≥ 10 μM) even shortened the AP. These findings can be explained by the drug's calcium channel inhibition, which counteracts the AP-prolonging effect generated by hERG blockade. Implementation of ibogaine's inhibitory effects on human ion channels in a computer model of a ventricular cardiomyocyte, on the other hand, suggested that ibogaine does prolong the AP in the human heart. We conclude that therapeutic concentrations of ibogaine have the propensity to prolong the QT interval of the electrocardiogram in humans. In some cases this may lead to cardiac arrhythmias. - Highlights: • We study effects of anti-addiction drug ibogaine on ionic currents in cardiomyocytes. • We assess the cardiac ion channel profile of ibogaine. • Ibogaine inhibits hERG potassium, sodium and calcium channels. • Ibogaine’s effects on ion channels are a potential

  3. Correlation of 64 row MDCT, echocardiography and cardiac catheterization angiography in assessment of pulmonary arterial anatomy in children with cyanotic congenital heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Chandrashekhar, Guruprasadh, E-mail: cguruprasadh@gmail.com [Departments of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research, Sector-12, Chandigarh 160012 (India); Sodhi, Kushaljit Singh, E-mail: sodhiks@gmail.com [Departments of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research, Sector-12, Chandigarh 160012 (India); Saxena, Akshay Kumar, E-mail: fatakshay@yahoo.com [Departments of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research, Sector-12, Chandigarh 160012 (India); Rohit, Manoj Kumar, E-mail: rohitmanoj@gmail.com [Department of Pediatric Cardiology, Post Graduate Institute of Medical Education and Research, Sector-12, Chandigarh 160012 (India); Khandelwal, Niranjan, E-mail: khandelwaln@hotmail.com [Departments of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research, Sector-12, Chandigarh 160012 (India)

    2012-12-15

    Objective: To study the correlation of low-dose 64-row multi-detector computed tomography (MDCT) with echocardiography and cardiac catheterization angiography (CCA) in the assessment of pulmonary arterial anatomy in children with cyanotic congenital heart disease (CCHD). Materials and methods: This prospective study included 105 children (74 males, 31 females) with CCHD, in the age group of 2 months to 20 years, who underwent 64-row MDCT examination (low-dose CT protocol), echocardiography and CCA for the assessment of pulmonary arteries, including visualization, presence of confluence, stenosis and collaterals. Statistical analysis was performed using the non-parametric statistical analysis test to evaluate the concordance or discordance between echocardiography, MDCT and CCA. Results: 64-row MDCT detected significantly more main and branch pulmonary arteries, patent pulmonary confluences, and more cases of pulmonary artery stenosis. CCA detected more major aorto-pulmonary collaterals than MDCT, whereas echocardiography failed to identify these major aorto-pulmonary collaterals. The effective CT radiation dose to patients less than 2 years of age was in the range of 0.7–2.5 mSv, where as the dose in patients more than 2 years of age ranged from that of 2.1 to 4.2 mSv, which is much less than the radiation dose reported in cardiac catheterization angiography. Conclusion: In cases where cardiac MRI cannot be performed, or is not sufficiently informative, low-dose 64-row MDCT correlates well with CCA and can provide adequate information about pulmonary arterial anatomy in children with cyanotic congenital heart disease, and can replace invasive cardiac catheterization angiography with markedly reduced radiation dosage to the patient.

  4. Correlation of 64 row MDCT, echocardiography and cardiac catheterization angiography in assessment of pulmonary arterial anatomy in children with cyanotic congenital heart disease

    International Nuclear Information System (INIS)

    Objective: To study the correlation of low-dose 64-row multi-detector computed tomography (MDCT) with echocardiography and cardiac catheterization angiography (CCA) in the assessment of pulmonary arterial anatomy in children with cyanotic congenital heart disease (CCHD). Materials and methods: This prospective study included 105 children (74 males, 31 females) with CCHD, in the age group of 2 months to 20 years, who underwent 64-row MDCT examination (low-dose CT protocol), echocardiography and CCA for the assessment of pulmonary arteries, including visualization, presence of confluence, stenosis and collaterals. Statistical analysis was performed using the non-parametric statistical analysis test to evaluate the concordance or discordance between echocardiography, MDCT and CCA. Results: 64-row MDCT detected significantly more main and branch pulmonary arteries, patent pulmonary confluences, and more cases of pulmonary artery stenosis. CCA detected more major aorto-pulmonary collaterals than MDCT, whereas echocardiography failed to identify these major aorto-pulmonary collaterals. The effective CT radiation dose to patients less than 2 years of age was in the range of 0.7–2.5 mSv, where as the dose in patients more than 2 years of age ranged from that of 2.1 to 4.2 mSv, which is much less than the radiation dose reported in cardiac catheterization angiography. Conclusion: In cases where cardiac MRI cannot be performed, or is not sufficiently informative, low-dose 64-row MDCT correlates well with CCA and can provide adequate information about pulmonary arterial anatomy in children with cyanotic congenital heart disease, and can replace invasive cardiac catheterization angiography with markedly reduced radiation dosage to the patient.

  5. Assessment of phase based dose modulation for improved dose efficiency in cardiac CT on an anthropomorphic motion phantom

    Science.gov (United States)

    Budde, Adam; Nilsen, Roy; Nett, Brian

    2014-03-01

    State of the art automatic exposure control modulates the tube current across view angle and Z based on patient anatomy for use in axial full scan reconstructions. Cardiac CT, however, uses a fundamentally different image reconstruction that applies a temporal weighting to reduce motion artifacts. This paper describes a phase based mA modulation that goes beyond axial and ECG modulation; it uses knowledge of the temporal view weighting applied within the reconstruction algorithm to improve dose efficiency in cardiac CT scanning. Using physical phantoms and synthetic noise emulation, we measure how knowledge of sinogram temporal weighting and the prescribed cardiac phase can be used to improve dose efficiency. First, we validated that a synthetic CT noise emulation method produced realistic image noise. Next, we used the CT noise emulation method to simulate mA modulation on scans of a physical anthropomorphic phantom where a motion profile corresponding to a heart rate of 60 beats per minute was used. The CT noise emulation method matched noise to lower dose scans across the image within 1.5% relative error. Using this noise emulation method to simulate modulating the mA while keeping the total dose constant, the image variance was reduced by an average of 11.9% on a scan with 50 msec padding, demonstrating improved dose efficiency. Radiation dose reduction in cardiac CT can be achieved while maintaining the same level of image noise through phase based dose modulation that incorporates knowledge of the cardiac reconstruction algorithm.

  6. Simulation of cardiac motion on non-Newtonian, pulsating flow development in the human left anterior descending coronary artery

    Science.gov (United States)

    Theodorakakos, A.; Gavaises, M.; Andriotis, A.; Zifan, A.; Liatsis, P.; Pantos, I.; Efstathopoulos, E. P.; Katritsis, D.

    2008-09-01

    This study aimed at investigating the effect of myocardial motion on pulsating blood flow distribution of the left anterior descending coronary artery in the presence of atheromatous stenosis. The moving 3D arterial tree geometry has been obtained from conventional x-ray angiograms obtained during the heart cycle and includes a number of major branches. The geometry reconstruction model has been validated against projection data from a virtual phantom arterial tree as well as with CT-based reconstruction data for the same patient investigated. Reconstructions have been obtained for a number of temporal points while linear interpolation has been used for all intermediate instances. Blood has been considered as a non-Newtonian fluid. Results have been obtained using the same pulse for the inlet blood flow rate but with fixed arterial tree geometry as well as under steady-state conditions corresponding to the mean flow rate. Predictions indicate that myocardial motion has only a minor effect on flow distribution within the arterial tree relative to the effect of the blood pressure pulse.

  7. Simulation of cardiac motion on non-Newtonian, pulsating flow development in the human left anterior descending coronary artery

    International Nuclear Information System (INIS)

    This study aimed at investigating the effect of myocardial motion on pulsating blood flow distribution of the left anterior descending coronary artery in the presence of atheromatous stenosis. The moving 3D arterial tree geometry has been obtained from conventional x-ray angiograms obtained during the heart cycle and includes a number of major branches. The geometry reconstruction model has been validated against projection data from a virtual phantom arterial tree as well as with CT-based reconstruction data for the same patient investigated. Reconstructions have been obtained for a number of temporal points while linear interpolation has been used for all intermediate instances. Blood has been considered as a non-Newtonian fluid. Results have been obtained using the same pulse for the inlet blood flow rate but with fixed arterial tree geometry as well as under steady-state conditions corresponding to the mean flow rate. Predictions indicate that myocardial motion has only a minor effect on flow distribution within the arterial tree relative to the effect of the blood pressure pulse

  8. Development of the Assessment Items of Debris Flow Using the Delphi Method

    Science.gov (United States)

    Byun, Yosep; Seong, Joohyun; Kim, Mingi; Park, Kyunghan; Yoon, Hyungkoo

    2016-04-01

    In recent years in Korea, Typhoon and the localized extreme rainfall caused by the abnormal climate has increased. Accordingly, debris flow is becoming one of the most dangerous natural disaster. This study aimed to develop the assessment items which can be used for conducting damage investigation of debris flow. Delphi method was applied to classify the realms of assessment items. As a result, 29 assessment items which can be classified into 6 groups were determined.

  9. Validation of On-Orbit Methodology for the Assessment of Cardiac Function and Changes in the Circulating Volume Using Ultrasound and Braslet-M Occlusion Cuffs

    Science.gov (United States)

    Hamilton, Douglas; Sargsyan, Ashot E.; Ebert, Douglas; Duncan, Michael; Bogomolov, Valery V.; Alferova, Irina V.; Matveev, Vladimir P.; Dulchavsky, Scott A.

    2010-01-01

    The objective of this joint U.S. - Russian project was the development and validation of an in-flight methodology to assess a number of cardiac and vascular parameters associated with circulating volume and its manipulation in long-duration space flight. Responses to modified Valsalva and Mueller maneuvers were measured by cardiac and vascular ultrasound (US) before, during, and after temporary volume reduction by means of Braslet-M thigh occlusion cuffs (Russia). Materials and Methods: The study protocol was conducted in 14 sessions on 9 ISS crewmembers, with an average exposure to microgravity of 122 days. Baseline cardiovascular measurements were taken by echocardiography in multiple modes (including tissue Doppler of both ventricles) and femoral and jugular vein imaging on the International Space Station (ISS). The Braslet devices were then applied and measurements were repeated after >10 minutes. The cuffs were then released and the hemodynamic recovery process was monitored. Modified Valsalva and Mueller maneuvers were used throughout the protocol. All US data were acquired by the HDI-5000 ultrasound system aboard the ISS (ATL/Philips, USA) during remotely guided sessions. The study protocol, including the use of Braslet-M for this purpose, was approved by the ISS Human Research Multilateral Review Board (HRMRB). Results: The effects of fluid sequestration on a number of echocardiographic and vascular parameters were readily detectable by in-flight US, as were responses to respiratory maneuvers. The overall volume status assessment methodology appears to be valid and practical, with a decrease in left heart lateral E (tissue Doppler) as one of the most reliable measures. Increase in the femoral vein cross-sectional areas was consistently observed with Braslet application. Other significant differences and trends within the extensive cardiovascular data were also observed. (Decreased - RV and LV preload indices, Cardiac Output, LV E all maneuvers, LV Stroke

  10. A new classifier-based strategy for in-silico ion-channel cardiac drug safety assessment

    OpenAIRE

    Mistry, Hitesh B.; Davies, Mark R.; Di Veroli, Giovanni Y.

    2015-01-01

    There is currently a strong interest in using high-throughput in-vitro ion-channel screening data to make predictions regarding the cardiac toxicity potential of a new compound in both animal and human studies. A recent FDA think tank encourages the use of biophysical mathematical models of cardiac myocytes for this prediction task. However, it remains unclear whether this approach is the most appropriate. Here we examine five literature data-sets that have been used to support the use of fou...

  11. Noninvasive continuous cardiac output monitoring in perioperative and intensive care medicine.

    Science.gov (United States)

    Saugel, B; Cecconi, M; Wagner, J Y; Reuter, D A

    2015-04-01

    The determination of blood flow, i.e. cardiac output, is an integral part of haemodynamic monitoring. This is a review on noninvasive continuous cardiac output monitoring in perioperative and intensive care medicine. We present the underlying principles and validation data of the following technologies: thoracic electrical bioimpedance, thoracic bioreactance, vascular unloading technique, pulse wave transit time, and radial artery applanation tonometry. According to clinical studies, these technologies are capable of providing cardiac output readings noninvasively and continuously. They, therefore, might prove to be innovative tools for the assessment of advanced haemodynamic variables at the bedside. However, for most technologies there are conflicting data regarding the measurement performance in comparison with reference methods for cardiac output assessment. In addition, each of the reviewed technology has its own limitations regarding applicability in the clinical setting. In validation studies comparing cardiac output measurements using these noninvasive technologies in comparison with a criterion standard method, it is crucial to correctly apply statistical methods for the assessment of a technology's accuracy, precision, and trending capability. Uniform definitions for 'clinically acceptable agreement' between innovative noninvasive cardiac output monitoring systems and criterion standard methods are currently missing. Further research must aim to further develop the different technologies for noninvasive continuous cardiac output determination with regard to signal recording, signal processing, and clinical applicability. PMID:25596280

  12. MRI of cardiac rhabdomyoma in the fetus

    Energy Technology Data Exchange (ETDEWEB)

    Kivelitz, Dietmar E.; Muehler, Matthias [Institut fuer Radiologie, Medizinische Fakultaet, Humboldt-Universitaet zu Berlin, Charite, Schumannstrasse 20/21, 10098, Berlin (Germany); Rake, Annett; Chaoui, Rabih [Klinik fuer Gynaekologie und Geburtshilfe, Medizinische Fakultaet, Humboldt-Universitaet zu Berlin, Charite, Schumannstrasse 20/21, 10098, Berlin (Germany); Scheer, Ianina [Klinik fuer Strahlenheilkunde, Abteilung Paediatrische Radiologie, Medizinische Fakultaet, Humboldt-Universitaet zu Berlin, Charite, Schumannstrasse 20/21, 10098, Berlin (Germany)

    2004-08-01

    Primary cardiac tumors are rarely diagnosed in utero and are usually seen on prenatal echocardiography. Cardiac rhabdomyomata can be associated with tuberous sclerosis. Prenatal MRI can be performed to assess associated malformations. This case report illustrates the ability of fetal MRI to image cardiac rhabdomyata and compares it with prenatal and postnatal echocardiography. (orig.)

  13. Technique for producing cardiac radionuclide motion images

    International Nuclear Information System (INIS)

    Sequential frames of different portions of the cardiac cycle are gated into a minicomputer by using an EKG signal recorded onto digital tape simultaneously with imaging information. Serial display of these frames on the computer oscilloscope or projection of 35-mm half frames of these images provides a cardiac motion image with information content adequate for qualitatively assessing cardiac motion. (U.S.)

  14. Four-dimensional computed tomography: a method of assessing right ventricular outflow tract and pulmonary artery deformations throughout the cardiac cycle

    Energy Technology Data Exchange (ETDEWEB)

    Schievano, Silvia; Capelli, Claudio; Young, Carol; Lurz, Philipp; Nordmeyer, Johannes; Owens, Catherine; Bonhoeffer, Philipp; Taylor, Andrew M. [UCL, Institute of Child Health and Great, Ormond Street Hospital for Children, Cardiovascular Unit, London (United Kingdom)

    2011-01-15

    To characterise 3D deformations of the right ventricular outflow tract (RVOT)/ pulmonary arteries (PAs) during the cardiac cycle and estimate the errors of conventional 2D assessments. Contrast-enhanced, ECG-gated cardiovascular computed tomography (CT) findings were retrospectively analysed from 12 patients. The acquisition of 3D images over 10 phases of the cardiac cycle created a four-dimensional CT (4DCT) dataset. The datasets were reconstructed and deformation measured at various levels of the RVOT/PAs in both space and time. Section planes were either static or dynamic relative to the motion of the structures. 4DCT enabled measurement and characterisation of in vivo 3D changes of patients' RVOT/PA during the cardiac cycle. The studied patient population showed a wide range of RVOT/PA morphologies, sizes and dynamics that develop late after surgical repair of congenital heart disease. There were also significant differences in the measured cross-sectional areas of the structures between static and dynamic section planes (up to 150%, p < 0.05) secondary to large 3D displacements and rotations. 4DCT imaging data suggest high variability in RVOT/PA dynamics and significant errors in deformation measurements if 3D analysis is not carried out. These findings play an important role for the development of novel percutaneous approaches to pulmonary valve intervention. (orig.)

  15. Non-invasive assessment of congenital pulmonary vein stenosis in children using cardiac-non-gated CT with 64-slice technology

    International Nuclear Information System (INIS)

    Background: Management of congenital pulmonary vein stenosis is a diagnostic challenge. Echocardiography may be insufficient and thus cardiac catheterization remains the reference standard in this setting. The aim of the study was to investigate the accuracy of cardiac-non-gated CT using 64-slice technology in detecting congenital pulmonary vein stenosis in children. Materials and methods: CT examinations were consecutively performed from May 2005 to December 2006 in 13 children aged 1.5-12 months (median 5 months) for suspected congenital pulmonary vein stenosis. Cardiac-non-gated CT acquisitions were performed after the peripheral injection of contrast agent. Pulmonary veins were evaluated for their pattern of connectivity from the lung to the left atrium and for the presence of stenosis. CT findings of pulmonary vein stenosis were compared with combined findings available from echocardiography, catheterization and surgery. Results: Pulmonary veins from the right lung (n = 29) and left lung (n = 26) were evaluated as separate structures (N = 55). Of the 55 structures, 32 had surgical and/or catheterization data and 45 had echocardiography for comparison. CT visualized 100% (55/55) of the investigated structures, while echocardiography visualized 82% (45/55). In the 13 subjects CT identified 10 stenotic pulmonary veins. CT confirmed the echocardiography suspicion of pulmonary vein stenosis in 100% (7/7) and established a new diagnosis in 3 other patients. CT agreed with surgery/catheterization in 100% (10/10) of the available comparisons. Conclusion: Cardiac-non-gated CT assessed the pulmonary veins more completely than echocardiography and should be considered as a viable alternative for invasive pulmonary venography for detecting pulmonary vein stenosis in children.

  16. Assessment of the Right Ventricular Function and Mass Using Cardiac Multi-Detector Computed Tomography in Patients with Chronic Obstructive Pulmonary Disease

    International Nuclear Information System (INIS)

    We wanted to assess the relationship between measurements of the right ventricular (RV) function and mass, with using cardiac multi-detector computed tomography (MDCT) and the severity of chronic obstructive pulmonary disease (COPD) as determined by the pulmonary function test (PFT). Measurements of PFT and cardiac MDCT were obtained in 33 COPD patients. Using the Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification, the patients were divided into three groups according to the severity of the disease: stage I (mild, n = 4), stage II (moderate, n = 15) and stage III (severe, n = 14). The RV function and the wall mass were obtained by cardiac MDCT. The results were compared among the groups using the Student-Newman-Keuls method. Person's correlation was used to evaluate the relationship between the right ventricular ejection fraction (RVEF) and the wall mass results with the PFT results. P-values less than 0.05 were considered statistically significant. The RVEF and mass were 47 ±3% and 41 ±2 g in stage I, 46 ±6% and 46 ±5 g in stage II, and 35 ±5% and 55 ±6 g in stage III, respectively. The RVEF was significantly lower in stage III than in stage I and II (p < 0.01). The RV mass was significantly different among the three stages, according to the disease severity of COPD (p < 0.05). The correlation was excellent between the MDCT results and forced expiratory volume in 1 sec (r = 0.797 for RVEF and r -0.769 for RV mass) and forced expiratory volume in 1 sec to the forced vital capacity (r = 0.745 for RVEF and r = -0.718 for RV mass). Our study shows that the mean RV wall mass as measured by cardiac MDCT correlates well with the COPD disease severity as determined by PFT

  17. Assessment of DNA double-strand breaks induced by intravascular iodinated contrast media following in vitro irradiation and in vivo, during paediatric cardiac catheterization.

    Science.gov (United States)

    Gould, Richard; McFadden, Sonyia L; Horn, Simon; Prise, Kevin M; Doyle, Philip; Hughes, Ciara M

    2016-01-01

    Paediatric cardiac catheterizations may result in the administration of substantial amounts of iodinated contrast media and ionizing radiation. The aim of this work was to investigate the effect of iodinated contrast media in combination with in vitro and in vivo X-ray radiation on lymphocyte DNA. Six concentrations of iodine (15, 17.5, 30, 35, 45, and 52.5 mg of iodine per mL blood) represented volumes of iodinated contrast media used in the clinical setting. Blood obtained from healthy volunteers was mixed with iodinated contrast media and exposed to radiation doses commonly used in paediatric cardiac catheterizations (0 mGy, 70 mGy, 140 mGy, 250 mGy and 450 mGy). Control samples contained no iodine. For in vivo experimentation, pre and post blood samples were collected from children undergoing cardiac catheterization, receiving iodine concentrations of up to 51 mg of iodine per mL blood and radiation doses of up to 400 mGy. Fluorescence microscopy was performed to assess γH2AX-foci induction, which corresponded to the number of DNA double-strand breaks. The presence of iodine in vitro resulted in significant increases of DNA double-strand breaks beyond that induced by radiation for ≥ 17.5 mg/mL iodine to blood. The in vivo effects of contrast media on children undergoing cardiac catheterization resulted in a 19% increase in DNA double-strand breaks in children receiving an average concentration of 19 mg/mL iodine to blood. A larger investigation is required to provide further information of the potential benefit of lowering the amount of iodinated contrast media received during X-ray radiation investigations. PMID:26549792

  18. A new classifier-based strategy for in-silico ion-channel cardiac drug safety assessment

    Directory of Open Access Journals (Sweden)

    Hitesh eMistry

    2015-03-01

    Full Text Available There is currently a strong interest in using high-throughput in-vitro ion-channel screening data to make predictions regarding the cardiac toxicity potential of a new compound in both animal and human studies. A recent FDA think tank encourages the use of biophysical mathematical models of cardiac myocytes for this prediction task. However, it remains unclear whether this approach is the most appropriate. Here we examine five literature data-sets that have been used to support the use of four different biophysical models and one statistical model for predicting cardiac toxicity in numerous species using various endpoints. We propose a simple model that represents the balance between repolarisation and depolarisation forces and compare the predictive power of the model against the original results (leave-one-out cross-validation. Our model showed equivalent performance when compared to the four biophysical models and one statistical model. We therefore conclude that this approach should be further investigated in the context of early cardiac safety screening when in-vitro potency data is generated.

  19. A prospective study of paediatric cardiac surgical microsystems: assessing the relationships between non-routine events, teamwork and patient outcomes

    NARCIS (Netherlands)

    Schraagen, J.M.C.; Schouten, T.; Smit, M.; Haas, F.; Beek, D. van der; Ven, J. van der; Barach, P.

    2011-01-01

    Objective: Paediatric cardiac surgery has a low error tolerance and demands high levels of cognitive and technical performance. Growing evidence suggests that further improvements in patient outcomes depend on system factors, in particular, effective team skills. The hypotheses that small intraopera

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

    Directory of Open Access Journals (Sweden)

    Lewis JE

    2011-09-01

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

  1. A dual propagation contours technique for semi-automated assessment of systolic and diastolic cardiac function by CMR

    Directory of Open Access Journals (Sweden)

    Calhoun David A

    2009-08-01

    Full Text Available Abstract Background Although cardiovascular magnetic resonance (CMR is frequently performed to measure accurate LV volumes and ejection fractions, LV volume-time curves (VTC derived ejection and filling rates are not routinely calculated due to lack of robust LV segmentation techniques. VTC derived peak filling rates can be used to accurately assess LV diastolic function, an important clinical parameter. We developed a novel geometry-independent dual-contour propagation technique, making use of LV endocardial contours manually drawn at end systole and end diastole, to compute VTC and measured LV ejection and filling rates in hypertensive patients and normal volunteers. Methods 39 normal volunteers and 49 hypertensive patients underwent CMR. LV contours were manually drawn on all time frames in 18 normal volunteers. The dual-contour propagation algorithm was used to propagate contours throughout the cardiac cycle. The results were compared to those obtained with single-contour propagation (using either end-diastolic or end-systolic contours and commercially available software. We then used the dual-contour propagation technique to measure peak ejection rate (PER and peak early diastolic and late diastolic filling rates (ePFR and aPFR in all normal volunteers and hypertensive patients. Results Compared to single-contour propagation methods and the commercial method, VTC by dual-contour propagation showed significantly better agreement with manually-derived VTC. Ejection and filling rates by dual-contour propagation agreed with manual (dual-contour – manual PER: -0.12 ± 0.08; ePFR: -0.07 ± 0.07; aPFR: 0.06 ± 0.03 EDV/s, all P = NS. However, the time for the manual method was ~4 hours per study versus ~7 minutes for dual-contour propagation. LV systolic function measured by LVEF and PER did not differ between normal volunteers and hypertensive patients. However, ePFR was lower in hypertensive patients vs. normal volunteers, while aPFR was

  2. Feasibility of free-breathing, GRAPPA-based, real-time cardiac cine assessment of left-ventricular function in cardiovascular patients at 3 T

    International Nuclear Information System (INIS)

    Highlights: • Grappa-based real time cine cardiac MRI is feasible for assessment of left ventricular function. • Significant underestimation of systolic function, peak ejection and filling rates needs to be considered. • Heart rate is the only positive predictor of the deviation of obtained parameters. - Abstract: Objectives: To determine the feasibility of free-breathing, GRAPPA-based, real-time (RT) cine 3 T cardiac magnetic resonance imaging (MRI) with high acceleration factors for the assessment of left-ventricular function in a cohort of patients as compared to conventional segmented cine imaging. Materials and methods: In this prospective cohort study, subjects with various cardiac conditions underwent MRI involving two RT cine sequences (high resolution and low resolution) and standard segmented cine imaging. Standard qualitative and quantitative parameters of left-ventricular function were quantified. Results: Among 25 subjects, 24 were included in the analysis (mean age: 50.5 ± 21 years, 67% male, 25% with cardiomyopathy). RT cine derived quantitative parameters of volumes and left ventricular mass were strongly correlated with segmented cine imaging (intraclass correlation coefficient [ICC]: >0.72 for both RT cines) but correlation for peak ejection and filling rates were moderate to poor for both RT cines (ICC < 0.40). Similarly, RT cines significantly underestimated peak ejection and filling rates (>103.2 ± 178 ml/s). Among patient-related factors, heart rate was strongly predictive for deviation of measurements (p < 0.05). Conclusions: RT cine MRI at 3 T is feasible for qualitative and quantitative assessment of left ventricular function for low and high-resolution sequences but results in significant underestimation of systolic function, peak ejection and filling rates

  3. Feasibility of free-breathing, GRAPPA-based, real-time cardiac cine assessment of left-ventricular function in cardiovascular patients at 3 T

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Xiaomei, E-mail: xiaomeizhunanjing@163.com [Institute of Clinical Radiology, Ludwig-Maximilians-University Hospital, Marchioninistrasse 15, 81377 Munich (Germany); Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, 300, Guangzhou Road, 210029 Nanjing, Jiangsu (China); Schwab, Felix, E-mail: flixschwab@googlemail.com [Institute of Clinical Radiology, Ludwig-Maximilians-University Hospital, Marchioninistrasse 15, 81377 Munich (Germany); Marcus, Roy, E-mail: Roy.Marcus@med.uni-muenchen.de [Institute of Clinical Radiology, Ludwig-Maximilians-University Hospital, Marchioninistrasse 15, 81377 Munich (Germany); Hetterich, Holger, E-mail: Holger.Hetterich@med.uni-muenchen.de [Institute of Clinical Radiology, Ludwig-Maximilians-University Hospital, Marchioninistrasse 15, 81377 Munich (Germany); Theisen, Daniel, E-mail: daniel.theisen@me.com [Institute of Clinical Radiology, Ludwig-Maximilians-University Hospital, Marchioninistrasse 15, 81377 Munich (Germany); Kramer, Harald, E-mail: Harald.Kramer@med.uni-muenchen.de [Institute of Clinical Radiology, Ludwig-Maximilians-University Hospital, Marchioninistrasse 15, 81377 Munich (Germany); Notohamiprodjo, Mike, E-mail: Mike.Notohamiprodjo@med.lmu.de [Department of Radiology, University of Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen (Germany); Schlett, Christopher L., E-mail: Christopher.Schlett@med.uni-heidelberg.de [Department of Radiology, University of Heidelberg, Neuenheimer Feld 110, 69120 Heidelberg (Germany); Nikolaou, Konstantin, E-mail: Konstantin.Nikolaou@med.uni-tuebingen.de [Department of Radiology, University of Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen (Germany); Reiser, Maximilian F., E-mail: Maximilian.Reiser@med.uni-muenchen.de [Institute of Clinical Radiology, Ludwig-Maximilians-University Hospital, Marchioninistrasse 15, 81377 Munich (Germany); and others

    2015-05-15

    Highlights: • Grappa-based real time cine cardiac MRI is feasible for assessment of left ventricular function. • Significant underestimation of systolic function, peak ejection and filling rates needs to be considered. • Heart rate is the only positive predictor of the deviation of obtained parameters. - Abstract: Objectives: To determine the feasibility of free-breathing, GRAPPA-based, real-time (RT) cine 3 T cardiac magnetic resonance imaging (MRI) with high acceleration factors for the assessment of left-ventricular function in a cohort of patients as compared to conventional segmented cine imaging. Materials and methods: In this prospective cohort study, subjects with various cardiac conditions underwent MRI involving two RT cine sequences (high resolution and low resolution) and standard segmented cine imaging. Standard qualitative and quantitative parameters of left-ventricular function were quantified. Results: Among 25 subjects, 24 were included in the analysis (mean age: 50.5 ± 21 years, 67% male, 25% with cardiomyopathy). RT cine derived quantitative parameters of volumes and left ventricular mass were strongly correlated with segmented cine imaging (intraclass correlation coefficient [ICC]: >0.72 for both RT cines) but correlation for peak ejection and filling rates were moderate to poor for both RT cines (ICC < 0.40). Similarly, RT cines significantly underestimated peak ejection and filling rates (>103.2 ± 178 ml/s). Among patient-related factors, heart rate was strongly predictive for deviation of measurements (p < 0.05). Conclusions: RT cine MRI at 3 T is feasible for qualitative and quantitative assessment of left ventricular function for low and high-resolution sequences but results in significant underestimation of systolic function, peak ejection and filling rates.

  4. [Cardiac evaluation before non-cardiac surgery].

    Science.gov (United States)

    Menzenbach, Jan; Boehm, Olaf

    2016-07-01

    Before non-cardiac surgery, evaluation of cardiac function is no frequent part of surgical treatment. European societies of anesthesiology and cardiology published consensus-guidelines in 2014 to present a reasonable approach for preoperative evaluation. This paper intends to differentiate the composite of perioperative risk and to display the guidelines methodical approach to handle it. Features to identify patients at risk from an ageing population with comorbidities, are the classification of surgical risk, functional capacity and risk indices. Application of diagnostic means, should be used adjusted to this risk estimation. Cardiac biomarkers are useful to discover risk of complications or mortality, that cannot be assessed by clinical signs. After preoperative optimization and perioperative cardiac protection, the observation of the postoperative period remains, to prohibit complications or even death. In consideration of limited resources of intensive care department, postoperative ward rounds beyond intensive care units are considered to be an appropriate instrument to avoid or recognize complications early to reduce postoperative mortality. PMID:27479258

  5. Assessment of subchannel code ASSERT-PV for flow-distribution predictions

    International Nuclear Information System (INIS)

    Highlights: • Assessment of the subchannel code ASSERT-PV 3.2 for the prediction of flow distribution. • Open literature and in-house experimental data to quantify ASSERT-PV predictions. • Model changes assessed against vertical and horizontal flow experiments. • Improvement of flow-distribution predictions under CANDU-relevant conditions. - Abstract: This paper reports an assessment of the recently released subchannel code ASSERT-PV 3.2 for the prediction of flow-distribution in fuel bundles, including subchannel void fraction, quality and mass fluxes. Experimental data from open literature and from in-house tests are used to assess the flow-distribution models in ASSERT-PV 3.2. The prediction statistics using the recommended model set of ASSERT-PV 3.2 are compared to those from previous code versions. Separate-effects sensitivity studies are performed to quantify the contribution of each flow-distribution model change or enhancement to the improvement in flow-distribution prediction. The assessment demonstrates significant improvement in the prediction of flow-distribution in horizontal fuel channels containing CANDU bundles

  6. Chagas Cardiomiopathy: The Potential of Diastolic Dysfunction and Brain Natriuretic Peptide in the Early Identification of Cardiac Damage

    OpenAIRE

    Ana Garcia-Alvarez; Marta Sitges; María-Jesús Pinazo; Ander Regueiro-Cueva; Elizabeth Posada; Silvia Poyatos; José Tomás Ortiz-Pérez; Magda Heras; Manel Azqueta; Joaquim Gascon; Ginés Sanz

    2010-01-01

    INTRODUCTION: Chagas disease remains a major cause of mortality in several countries of Latin America and has become a potential public health problem in non-endemic countries as a result of migration flows. Cardiac involvement represents the main cause of mortality, but its diagnosis is still based on nonspecific criteria with poor sensitivity. Early identification of patients with cardiac involvement is desirable, since early treatment may improve prognosis. This study aimed to assess the r...

  7. Assessing cerebrospinal fluid flow connectivity using 3D gradient echo phase contrast velocity encoded MRI

    International Nuclear Information System (INIS)

    The aim of this study is to investigate the feasibility of using three-directional velocity encoded 3D gradient echo (GE) phase contrast (PC) imaging to assess cerebrospinal fluid (CSF) flow connectivity in the human brain. Five healthy volunteers were scanned using low velocity sensitivity (Venc = 0.04–0.05 m s−1). Flow–time curves were compared to standard 2D PC scans. The 3D data were used to reconstruct in vivo CSF flow volumes based on time-averaged phase-difference information, and the patency of the CSF flow pathways was assessed using nearest-neighbour connectivity. A pulsatile flow phantom was used to gauge the measurement accuracy of the CSF flow volumes at low flow velocities. Flow connectivity from the lateral ventricles down to the cisterna magna was successfully demonstrated in all volunteers. The phantom tests showed a good distinction between the flow cavities and the background noise. 3D PC imaging results in CSF flow waveforms with similar pulsatility but underestimated peak velocities compared to 2D PC data. 3D time-resolved velocity encoded GE imaging has successfully been applied to assess CSF flow connectivity in normal subjects

  8. Flow mapping for assessment of native and repaired valves

    International Nuclear Information System (INIS)

    Color Doppler flow mapping (CDFM) was performed in 47 normal women ages 18-41 mean (m) 28 to determine the normal flow phenomena across each of the 4 heart valves. The group included: 15 elite marathon runners average run (ave.) 70 miles/week, heart rate (HR) 35-54 (m 45); 14 joggers ave. 40 mi/wkm HR 40-69 (m 53); and 17 controls 0 mi/wk, HR 49-93 (m 77). 2-D echo and CDFM defined the motion of each valve, including the presence of mitral valve prolapse (MVP), the ventricular inflow and outflow patterns and the presence of regurgitation

  9. A Refined Multiscale Self-Entropy Approach for the Assessment of Cardiac Control Complexity: Application to Long QT Syndrome Type 1 Patients

    OpenAIRE

    Vlasta Bari; Giulia Girardengo; Andrea Marchi; Beatrice De Maria; Paul A Brink; Lia Crotti; Schwartz, Peter J.; Alberto Porta

    2015-01-01

    The study proposes the contemporaneous assessment of conditional entropy (CE) and self-entropy (sE), being the two terms of the Shannon entropy (ShE) decomposition, as a function of the time scale via refined multiscale CE (RMSCE) and sE (RMSsE) with the aim at gaining insight into cardiac control in long QT syndrome type 1 (LQT1) patients featuring the KCNQ1-A341V mutation. CE was estimated via the corrected CE (CCE) and sE as the difference between the ShE and CCE. RMSCE and RMSsE were comp...

  10. Cardiac rehabilitation

    Science.gov (United States)

    ... attack or other heart problem. You might consider cardiac rehab if you have had: Heart attack Coronary heart disease (CHD) Heart failure Angina (chest pain) Heart or heart valve surgery Heart transplant Procedures such as angioplasty and stenting In some ...

  11. Cardiac Rehabilitation

    Science.gov (United States)

    Cardiac rehabilitation (rehab) is a medically supervised program to help people who have A heart attack Angioplasty or coronary artery bypass grafting for coronary heart disease A heart valve repair or replacement A ...

  12. Cardiac sarcoidosis

    OpenAIRE

    Costello BT; Nadel J.; Taylor AJ

    2016-01-01

    Benedict T Costello,1,2 James Nadel,3 Andrew J Taylor,1,21Department of Cardiovascular Medicine, The Alfred Hospital, 2Baker IDI Heart and Diabetes Research Institute, Melbourne, VIC, 3School of Medicine, University of Notre Dame, Sydney, NSW, Australia Abstract: Cardiac sarcoidosis is a rare but life-threatening condition, requiring a high degree of clinical suspicion and low threshold for investigation to make the diagnosis. The cardiac manifestations include heart failure, conducting syst...

  13. Assessing changes in water flow regulation in Chongqing region, China.

    Science.gov (United States)

    Xiao, Yang; Xiao, Qiang; Ouyang, Zhiyun; Maomao, Qin

    2015-06-01

    Water flow regulation is an important ecosystem service that significantly impacts on ecological quality and social benefits. With the aim of improving our understanding of ecosystems and proposing strategies for optimizing ecosystem services, a geographic information system (GIS)-based approach was designed to estimate and map regulated water flow in the Chongqing region of China. In this study, we applied the integrated valuation of environmental services and tradeoffs (InVEST) model and mathematical simulations to estimate the provision of the regulated water flow across space and time in 2000, 2005, and 2010. The results indicated that this ecosystem service had improved by 2.07 % from 2000 to 2010 as a result of human activities (such as vegetation restoration) and climatic interaction. Places with positive changes mainly occurred in high mountain areas, whereas places with negative changes were mainly distributed in resettlement areas along the Yangtze River. The type of ecosystem in areas with high mountains and steep slopes was a relatively minor contributor to the total service, but this ecosystem had the higher water flow regulation capacity. Moreover, with the increase in altitude and slope, the percentage contribution of forest increased significantly from 2000 to 2010; by contrast, the percentage contribution of cropland decreased rapidly. As for the impacts, the spatial variation of water flow regulation in the Chongqing region had a significant relation with climate and human activities at the regional scale. These results provided specific information that could be used to strengthen necessary public awareness about the protection and restoration of ecosystems. PMID:25980726

  14. Analysis of tidal expiratory flow pattern in the assessment of histamine-induced bronchoconstriction.

    OpenAIRE

    Morris, M. J.; Madgwick, R. G.; Lane, D. J.

    1995-01-01

    BACKGROUND--There are times in clinical practice when it would be useful to be able to assess the severity of airways obstruction from tidal breathing. Three indices of airways obstruction derived from analysis of resting tidal expiratory flow have previously been described: (1) Tme/TE = time to reach maximum expiratory flow/expiratory time; (2) Krs = decay constant of exponential fitted to tidal expiratory flow versus time curve; and (3) EV = extrapolated volume--that is, area under the curv...

  15. Pesticide Flow Analysis to Assess Human Exposure in Greenhouse Flower Production in Colombia

    OpenAIRE

    Binder, Claudia R.; Camilo Lesmes-Fabian

    2013-01-01

    Human exposure assessment tools represent a means for understanding human exposure to pesticides in agricultural activities and managing possible health risks. This paper presents a pesticide flow analysis modeling approach developed to assess human exposure to pesticide use in greenhouse flower crops in Colombia, focusing on dermal and inhalation exposure. This approach is based on the material flow analysis methodology. The transfer coefficients were obtained using the whole body dosimetry ...

  16. Risk assessment of debris flow in Yushu seismic area in China: a perspective for the reconstruction

    OpenAIRE

    H. X. Lan; L. P. Li; Zhang, Y. S.; Gao, X; H. J. Liu

    2013-01-01

    The 14 April 2010 Ms = 7.1 Yushu Earthquake (YE) had caused severe damage in the Jiegu township, the residential centre of Yushu Tibetan Autonomous Prefecture, Qinghai Province, China. In view of the fragile geological conditions after YE, risk assessment of secondary geohazards becomes an important concern for the reconstruction. A quantitative methodology was developed to assess the risk of debris flow by taking into account important intensity information. Debris flow sce...

  17. Cardiac dysfunction assessed by echocardiographic tissue Doppler imaging is an independent predictor of mortality in the general population

    DEFF Research Database (Denmark)

    Mogelvang, Rasmus; Sogaard, Peter; Pedersen, Sune A;

    2009-01-01

    ; P=0.001), were significant predictors of death in Cox proportional-hazards models adjusted for clinical variables (age, sex, body mass index, heart rate, hypertension, diabetes mellitus, and ischemic heart disease) and conventional echocardiography. The adjusted hazard ratio for death in the third...... parameters, left ventricular dysfunction by TDI is a powerful and independent predictor of death, especially when systolic performance and diastolic performance are considered together, recognizing their interdependency and their complex relation to deteriorating cardiac function....

  18. Magnetic Resonance Elastography as a Method for the Assessment of Effective Myocardial Stiffness throughout the Cardiac Cycle

    OpenAIRE

    Kolipaka, Arunark; Araoz, Philip A; McGee, Kiaran P.; Manduca, Armando; Ehman, Richard L.

    2010-01-01

    Magnetic resonance elastography (MRE) is a noninvasive technique in which images of externally generated waves propagating in tissue are used to measure stiffness. The first aim is to determine, from a range of driver configurations the optimal driver for the purpose of generating waves within the heart in vivo. The second aim is to quantify the shear stiffness of normal myocardium throughout the cardiac cycle using MRE and to compare MRE stiffness to left ventricular (LV) chamber pressure in...

  19. Multiscale Entropy Analysis of EEG for Assessment of Post-Cardiac Arrest Neurological Recovery Under Hypothermia in Rats

    OpenAIRE

    Kang, Xiaoxu; Jia, Xiaofeng; Geocadin, Romergryko G.; Thakor, Nitish V.; Maybhate, Anil

    2009-01-01

    Neurological complications after cardiac arrest (CA) can be fatal. Although hypothermia has been shown to be beneficial, understanding the mechanism and establishing neurological outcomes remains challenging because effects of CA and hypothermia are not well characterized. This paper aims to analyze EEG (and the α-rhythms) using multiscale entropy (MSE) to demonstrate the ability of MSE in tracking changes due to hypothermia and compare MSE during early recovery with long-term neurological ex...

  20. Assessment by Flow Cytometry of Cytokine Production in Malnourished Children

    OpenAIRE

    Rodríguez, Leonor; González, Cristina; Flores, Luis; Jiménez-Zamudio, Luis; Graniel, Jaime; Ortiz, Rocío

    2005-01-01

    Malnutrition in children is associated with an increased risk of infection and death. Multiple abnormalities in the immune response, including cytokine production, in protein energy-malnourished children have been described and could account for the increased severity and frequency of infections. In this study, we used flow cytometry to investigate the effects of malnutrition on the production of cytokines (interleukin-2 [IL-2], gamma interferon [IFN-γ], IL-4, and IL-10) in CD4+ and CD8+ cell...

  1. Assessment of environmental flow requirements in Buzi River basin, Mozambique

    OpenAIRE

    Lagerblad, Lovisa

    2010-01-01

    Rivers belong to the world’s most complex ecosystems but increasing demands for water are degrading rivers worldwide. The increase in human populations and activities has resulted in an intense and difficult conflict between the development of rivers as a natural resource and their function as living ecosystems. It is now widely recognized that a naturally variable flow regime is required to sustain freshwater ecosystems. Many countries that experience river degradation have started to implem...

  2. Automated quantification of cardiac short-axis multi-slice CT images for assessment of left ventricular global function

    Science.gov (United States)

    Danilouchkine, Mikhail G.; Admiraal-Behloul, Faiza; van der Geest, Rob J.; Lelieveldt, Boudewijn P. F.; Reiber, Johan H. C.

    2005-04-01

    This paper describes a method for automatic contour detection in reformatted short-axis (SA) cardiac computed tomography (CT) using a virtual exploring robot. The robot is a tricycle with a steering front wheel. Its motion obeys a set of kinematic equations and is subject to the non-holonomic constraints. The robot is designed to navigate in the binary representation of a cardiac image, consisting of the allowed navigational and obstacle spaces. It is initially positioned inside the allowed navigational space. Avoiding obstacles, the robot autonomously cruises through the navigational space and collects information about the location of the left ventricular (LV) boundaries. Consequently, the obtained information is used to reconstruct the endocardial and epicardial contours. Validation of the method was performed on in-vivo multislice multiphase short-axis cardiac CT images of ten subjects. Results showed good correlation between the quantitative parameters, computed from manual and automatic segmentation: for end-diastolic volume (EDV) r=0.99, for end-systolic volume (ESV) r=0.98, ejection fraction (EF) r=0.83, and LV mass (LVM) r=0.95.

  3. Magnetic resonance elastography as a method for the assessment of effective myocardial stiffness throughout the cardiac cycle.

    Science.gov (United States)

    Kolipaka, Arunark; Araoz, Philip A; McGee, Kiaran P; Manduca, Armando; Ehman, Richard L

    2010-09-01

    MR elastography (MRE) is a noninvasive technique in which images of externally generated waves propagating in tissue are used to measure stiffness. The first aim is to determine, from a range of driver configurations, the optimal driver for the purpose of generating waves within the heart in vivo. The second aim is to quantify the shear stiffness of normal myocardium throughout the cardiac cycle using MRE and to compare MRE stiffness to left ventricular chamber pressure in an in vivo pig model. MRE was performed in six pigs with six different driver setups, including no motion, three noninvasive drivers, and two invasive drivers. MRE wave displacement amplitudes were calculated for each driver. During the same MRI examination, left ventricular pressure and MRI-measured left ventricular volume were obtained, and MRE myocardial stiffness was calculated for 20 phases of the cardiac cycle. No discernible waves were imaged when no external motion was applied, and a single pneumatic drum driver produced higher amplitude waves than the other noninvasive drivers (P < 0.05). Pressure-volume loops overlaid onto stiffness-volume loops showed good visual agreement. Pressure and MRE-measured effective stiffness showed good correlation (R(2) = 0.84). MRE shows potential as a noninvasive method for estimating effective myocardial stiffness throughout the cardiac cycle. PMID:20578052

  4. Prolonged cardiac arrest and resuscitation by extracorporeal life support: favourable outcome without preceding anticoagulation in an experimental setting.

    Science.gov (United States)

    Foerster, K; D'Inka, M; Beyersdorf, F; Benk, C; Nguyen-Thanh, T; Mader, I; Fritsch, B; Ihling, C; Mueller, K; Heilmann, C; Trummer, G

    2013-11-01

    State-of-the-art cardiopulmonary resuscitation (CPR) restores circulation with inconsistent blood-flow and pressure. Extracorporeal life support (ECLS) following CPR opens the opportunity for "controlled reperfusion". In animal experiments investigating CPR with ECLS, systemic anticoagulation before induced cardiac arrest is normal, but a major point of dispute, since preliminary heparinization in patients undergoing unwitnessed cardiac arrest is impossible. In this study, we investigated options for ECLS after an experimental 15 minutes normothermic cardiac arrest, without preceding anticoagulation, in pigs. Neurological recovery was assessed by a scoring system, electroencephalography and brain magnetic resonance imaging. Additionally, brain histology was performed on day seven after cardiac arrest. We demonstrated that preliminary heparin administration was not necessary for survival or neurological recovery in this setting. Heparin flushing of the cannulae seemed sufficient to avoid thrombus formation. These findings may ease the way to using ECLS in patients with sudden cardiac arrest. PMID:23827862

  5. Assessment of the dose distribution inside a cardiac cath lab using TLD measurements and Monte Carlo simulations

    International Nuclear Information System (INIS)

    Over the last decade, there was a substantial increase in the number of interventional cardiology procedures worldwide, and the corresponding ionizing radiation doses for both the medical staff and patients became a subject of concern. Interventional procedures in cardiology are normally very complex, resulting in long exposure times. Also, these interventions require the operator to work near the patient and, consequently, close to the primary X-ray beam. Moreover, due to the scattered radiation from the patient and the equipment, the medical staff is also exposed to a non-uniform radiation field that can lead to a significant exposure of sensitive body organs and tissues, such as the eye lens, the thyroid and the extremities. In order to better understand the spatial variation of the dose and dose rate distributions during an interventional cardiology procedure, the dose distribution around a C-arm fluoroscopic system, in operation in a cardiac cath lab at Portuguese Hospital, was estimated using both Monte Carlo (MC) simulations and dosimetric measurements. To model and simulate the cardiac cath lab, including the fluoroscopic equipment used to execute interventional procedures, the state-of-the-art MC radiation transport code MCNPX 2.7.0 was used. Subsequently, Thermo-Luminescent Detector (TLD) measurements were performed, in order to validate and support the simulation results obtained for the cath lab model. The preliminary results presented in this study reveal that the cardiac cath lab model was successfully validated, taking into account the good agreement between MC calculations and TLD measurements. The simulated results for the isodose curves related to the C-arm fluoroscopic system are also consistent with the dosimetric information provided by the equipment manufacturer (Siemens). The adequacy of the implemented computational model used to simulate complex procedures and map dose distributions around the operator and the medical staff is discussed, in

  6. Affect intensity and cardiac arousal.

    Science.gov (United States)

    Blascovich, J; Brennan, K; Tomaka, J; Kelsey, R M; Hughes, P; Coad, M L; Adlin, R

    1992-07-01

    Relationships between affect intensity and basal, evoked, and perceived cardiac arousal were investigated in 3 experiments. Affect intensity was assessed using Larsen and Diener's (1987) Affect Intensity Measure (AIM). Cardiac arousal was evoked with exercise in the 1st study and with mental arithmetic in the 2nd and 3rd. Perceived cardiac arousal was measured under optimal conditions using a standard heartbeat discrimination procedure. Women as a group scored higher on the AIM. Affect intensity was unrelated to basal or evoked cardiac arousal and was negatively related to perceived cardiac arousal in all 3 studies. Data suggest that affect intensity, although unrelated to actual physiological arousal, is negatively related to the accuracy with which individuals perceive their own arousal. Results are discussed within the context of an expanded arousal-regulation model (Blascovich, 1990). PMID:1494983

  7. Assessment of PRISM responses to loss of flow events

    International Nuclear Information System (INIS)

    The Nuclear Regulatory Commission (NRC), with Brookhaven National Laboratory providing technical support, is continuing a preapplication review of the 471 MWt, Advanced Liquid Metal Reactor (ALMR), PRISM by General Electric. The revised design has been evaluated using the SSC code, for a series of loss of flow events (LOF) with and without Gas Expansion Modules (GEMs). These devices have a net worth of 69 cents and have reduced the seriousness of the LOF in PRISM. However, it was found that the extremely low probability case of an instantaneous loss of 4 EM pumps without scram could lead to sodium boiling even with the GEMs. (author)

  8. Assessing Measures of Order Flow Toxicity via Perfect Trade Classification

    DEFF Research Database (Denmark)

    Andersen, Torben G.; Bondarenko, Oleg

    The VPIN, or Volume-synchronized Probability of INformed trading, metric is introduced by Easley, Lopez de Prado and O'Hara (ELO) as a real-time indicator of order flow toxicity. They find the measure useful in predicting return volatility and conclude it may help signal impending market turmoil....... The VPIN metric involves decomposing volume into active buys and sells. We use the best-bid-offer (BBO) files from the CME Group to construct (near) perfect trade classification measures for the E-mini S&P 500 futures contract. We investigate the accuracy of the ELO Bulk Volume Classification (BVC...

  9. Assessment of Flow Control Devices for Transonic Cavity Flows Using DES and LES

    Science.gov (United States)

    Barakos, G. N.; Lawson, S. J.; Steijl, R.; Nayyar, P.

    Since the implementation of internal carriage of stores on military aircraft, transonic flows in cavities were put forward as a model problem for validation of CFD methods before design studies of weapon bays can be undertaken. Depending on the free-stream Mach number and the cavity dimensions, the flow inside the cavity can become very unsteady. Below a critical length-to-depth ratio (L/D), the flow has enough energy to span across the cavity opening and a shear layer develops. When the shear layer impacts the downstream cavity corner, acoustical disturbances are generated and propagated upstream, which in turn causes further instabilities at the cavity front and a feedback loop is maintained. The acoustic environment in the cavity is so harsh in these circumstances that the noise level at the cavity rear has been found to approach 170 dB and frequencies near 1 kHz are created. The effect of this unsteady environment on the structural integrity of the contents of the cavity (e.g. stores, avionics, etc.) can be serious. Above the critical L/D ratio, the shear layer no longer has enough energy to span across the cavity and dips into it. Although this does not produce as high noise levels and frequencies as shorter cavities, the differential pressure along the cavity produces large pitching moments making store release difficult. Computational fluid dynamics analysis of cavity flows, based on the Reynolds-Averaged Navier—Stokes equations was only able to capture some of the flow physics present. On the other hand, results obtained with Large-Eddy Simulation or Detached-Eddy Simulation methods fared much better and for the cases computed, quantitative and qualitative agreement with experimental data has been obtained.

  10. Noninvasive monitoring of cardiac function in a chronic ischemic heart failure model in the rat: Assessment with tissue Doppler and non-Doppler 2D strain echocardiography

    Directory of Open Access Journals (Sweden)

    Baumann Gert

    2011-05-01

    Full Text Available Abstract Objectives Feasibility of noninvasive monitoring of cardiac function after surgically induced ischemic cardiomyopathy with tissue Doppler and non-Doppler 2D strain echocardiography in rats. Background The optimal method for quantitative assessment of global and regional ventricular function in rats with chronic heart failure for research purposes remains unclear. Methods 20 rats underwent suture ligation of the left anterior descending coronary artery via a left thoracotomy to induce ischemic cardiomyopathy. Echocardiographic examination with estimation of left ventricular wall thickness, diameters, fractional shortening, ejection fraction, wall velocities as well as radial strain were performed before and 4 weeks after surgery. Results Mean LVEF decreased from 70 ± 6% to 40 ± 8% (p Conclusion It is feasible to assess dimensions, global function, and regional contractility with echocardiography in rats suffering from chronic heart failure after myocardial infarction. Particularly regional function can be exactly evaluated if tissue Doppler and 2D strain is used.

  11. Assessing continuum postulates in simulations of granular flow

    Energy Technology Data Exchange (ETDEWEB)

    Rycroft, Chris; Kamrin, Ken; Bazant, Martin

    2008-08-26

    Continuum mechanics relies on the fundamental notion of a mesoscopic volume"element" in which properties averaged over discrete particles obey deterministic relationships. Recent work on granular materials suggests a continuum law may be inapplicable, revealing inhomogeneities at the particle level, such as force chains and slow cage breaking. Here, we analyze large-scale three-dimensional Discrete-Element Method (DEM) simulations of different granular flows and show that an approximate"granular element" defined at the scale of observed dynamical correlations (roughly three to five particle diameters) has a reasonable continuum interpretation. By viewing all the simulations as an ensemble of granular elements which deform and move with the flow, we can track material evolution at a local level. Our results confirm some of the hypotheses of classical plasticity theory while contradicting others and suggest a subtle physical picture of granular failure, combining liquid-like dependence on deformation rate and solid-like dependence on strain. Our computational methods and results can be used to guide the development of more realistic continuum models, based on observed local relationships betweenaverage variables.

  12. The use of product life cycle assessment for materials flow management

    International Nuclear Information System (INIS)

    The present paper deals with the significance of life cycle assessments for the ecological restructuring of market economies. It gives examples of materials flow management and points out the life cycle assessment as a method for valuating products and processes. (orig.)

  13. Cardiac echinococcosis

    Directory of Open Access Journals (Sweden)

    Ivanović-Krstić Branislava A.

    2002-01-01

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

  14. Anti-addiction drug ibogaine inhibits voltage-gated ionic currents: a study to assess the drug's cardiac ion channel profile.

    Science.gov (United States)

    Koenig, Xaver; Kovar, Michael; Rubi, Lena; Mike, Agnes K; Lukacs, Peter; Gawali, Vaibhavkumar S; Todt, Hannes; Hilber, Karlheinz; Sandtner, Walter

    2013-12-01

    The plant alkaloid ibogaine has promising anti-addictive properties. Albeit not licensed as a therapeutic drug, and despite hints that ibogaine may perturb the heart rhythm, this alkaloid is used to treat drug addicts. We have recently reported that ibogaine inhibits human ERG (hERG) potassium channels at concentrations similar to the drugs affinity for several of its known brain targets. Thereby the drug may disturb the heart's electrophysiology. Here, to assess the drug's cardiac ion channel profile in more detail, we studied the effects of ibogaine and its congener 18-Methoxycoronaridine (18-MC) on various cardiac voltage-gated ion channels. We confirmed that heterologously expressed hERG currents are reduced by ibogaine in low micromolar concentrations. Moreover, at higher concentrations, the drug also reduced human Nav1.5 sodium and Cav1.2 calcium currents. Ion currents were as well reduced by 18-MC, yet with diminished potency. Unexpectedly, although blocking hERG channels, ibogaine did not prolong the action potential (AP) in guinea pig cardiomyocytes at low micromolar concentrations. Higher concentrations (≥ 10 μM) even shortened the AP. These findings can be explained by the drug's calcium channel inhibition, which counteracts the AP-prolonging effect generated by hERG blockade. Implementation of ibogaine's inhibitory effects on human ion channels in a computer model of a ventricular cardiomyocyte, on the other hand, suggested that ibogaine does prolong the AP in the human heart. We conclude that therapeutic concentrations of ibogaine have the propensity to prolong the QT interval of the electrocardiogram in humans. In some cases this may lead to cardiac arrhythmias. PMID:23707769

  15. Anti-addiction drug ibogaine inhibits voltage-gated ionic currents: A study to assess the drug's cardiac ion channel profile☆

    Science.gov (United States)

    Koenig, Xaver; Kovar, Michael; Rubi, Lena; Mike, Agnes K.; Lukacs, Peter; Gawali, Vaibhavkumar S.; Todt, Hannes; Hilber, Karlheinz; Sandtner, Walter

    2013-01-01

    The plant alkaloid ibogaine has promising anti-addictive properties. Albeit not licenced as a therapeutic drug, and despite hints that ibogaine may perturb the heart rhythm, this alkaloid is used to treat drug addicts. We have recently reported that ibogaine inhibits human ERG (hERG) potassium channels at concentrations similar to the drugs affinity for several of its known brain targets. Thereby the drug may disturb the heart's electrophysiology. Here, to assess the drug's cardiac ion channel profile in more detail, we studied the effects of ibogaine and its congener 18-Methoxycoronaridine (18-MC) on various cardiac voltage-gated ion channels. We confirmed that heterologously expressed hERG currents are reduced by ibogaine in low micromolar concentrations. Moreover, at higher concentrations, the drug also reduced human Nav1.5 sodium and Cav1.2 calcium currents. Ion currents were as well reduced by 18-MC, yet with diminished potency. Unexpectedly, although blocking hERG channels, ibogaine did not prolong the action potential (AP) in guinea pig cardiomyocytes at low micromolar concentrations. Higher concentrations (≥ 10 μM) even shortened the AP. These findings can be explained by the drug's calcium channel inhibition, which counteracts the AP-prolonging effect generated by hERG blockade. Implementation of ibogaine's inhibitory effects on human ion channels in a computer model of a ventricular cardiomyocyte, on the other hand, suggested that ibogaine does prolong the AP in the human heart. We conclude that therapeutic concentrations of ibogaine have the propensity to prolong the QT interval of the electrocardiogram in humans. In some cases this may lead to cardiac arrhythmias. PMID:23707769

  16. Cardiac sarcoidosis

    Science.gov (United States)

    Smedema, J.P.; Zondervan, P.E.; van Hagen, P.; ten Cate, F.J.; Bresser, P.; Doubell, A.F.; Pattynama, P.; Hoogsteden, H.C.; Balk, A.H.M.M.

    2002-01-01

    Sarcoidosis is a multi-system granulomatous disorder of unknown aetiology. Symptomatic cardiac involvement occurs in approximately 5% of patients. The prevalence of sarcoidosis in the Netherlands is unknown, but estimated to be approximately 20 per 100,000 population (3200 patients). We report on five patients who presented with different manifestations of cardiac sarcoidosis, and give a brief review on the current management of this condition. Magnetic Resonance Imaging (MRI) can be of great help in diagnosing this condition as well as in the follow-up of the response to therapy. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6 PMID:25696121

  17. Assessment of the dose distribution inside a cardiac cath lab using TLD measurements and Monte Carlo simulations

    Science.gov (United States)

    Baptista, M.; Teles, P.; Cardoso, G.; Vaz, P.

    2014-11-01

    Over the last decade, there was a substantial increase in the number of interventional cardiology procedures worldwide, and the corresponding ionizing radiation doses for both the medical staff and patients became a subject of concern. Interventional procedures in cardiology are normally very complex, resulting in long exposure times. Also, these interventions require the operator to work near the patient and, consequently, close to the primary X-ray beam. Moreover, due to the scattered radiation from the patient and the equipment, the medical staff is also exposed to a non-uniform radiation field that can lead to a significant exposure of sensitive body organs and tissues, such as the eye lens, the thyroid and the extremities. In order to better understand the spatial variation of the dose and dose rate distributions during an interventional cardiology procedure, the dose distribution around a C-arm fluoroscopic system, in operation in a cardiac cath lab at Portuguese Hospital, was estimated using both Monte Carlo (MC) simulations and dosimetric measurements. To model and simulate the cardiac cath lab, including the fluoroscopic equipment used to execute interventional procedures, the state-of-the-art MC radiation transport code MCNPX 2.7.0 was used. Subsequently, Thermo-Luminescent Detector (TLD) measurements were performed, in order to validate and support the simulation results obtained for the cath lab model. The preliminary results presented in this study reveal that the cardiac cath lab model was successfully validated, taking into account the good agreement between MC calculations and TLD measurements. The simulated results for the isodose curves related to the C-arm fluoroscopic system are also consistent with the dosimetric information provided by the equipment manufacturer (Siemens). The adequacy of the implemented computational model used to simulate complex procedures and map dose distributions around the operator and the medical staff is discussed, in

  18. Non-invasive assessment of the effect of cardiac sympathetic innervation on metabolism of the human heart

    Energy Technology Data Exchange (ETDEWEB)

    Bengel, F.M.; Ziegler, S.I.; Nekolla, S.G.; Odaka, K.; Schwaiger, M. [Muenchen Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin; Ueberfuhr, P.; Reichart, B. [Muenchen Univ. (Germany). Herzchirurgische Klinik

    2000-11-01

    The role of cardiac sympathetic nerves in the regulation of myocardial metabolism is not well defined. Owing to the presence of incomplete reinnervation, heart transplant recipients provide a unique model to study the effects of efferent sympathetic innervation. Using this model, we sought to determine the influence of cardiac sympathetic signals on substrate utilisation and overall oxidative metabolism. In 21 transplant recipients, positron emission tomography was applied to determine sympathetic innervation with the noradrenaline analogue carbon-11 hydroxyephedrine, oxidative metabolism with carbon-11 acetate (n=14), and glucose utilisation with fluorine-18 fluorodeoxyglucose (n=7). The reinnervated area comprised 22%{+-}20% of the left ventricle. Oxidative metabolism was similar in denervated and reinnervated myocardium [0.06{+-}0.01 vs 0.06{+-}0.01/min for k(mono)], while glucose uptake was significantly higher in denervated myocardium (6.9{+-}6.6 vs 6.0{+-}6.2 {mu}mol/min/100 g; P=0.03). Reinnervation mainly occurred in the territory of the left anterior descending artery, where retention of {sup 11}C-hydroxyephedrine (6.8{+-}2.7%/min) was higher compared with territories of the left circumflex (4.1{+-}1.7%/min; P<0.01) and right coronary (3.8{+-}1.1%/min; P<0.01) arteries. Oxidative metabolism was similar in all three territories, but compared with the reinnervated territory of the left anterior descending artery (53%{+-}16% of maximum), relative FDG uptake was higher in territories of the left circumflex (76%{+-}6%, P<0.01) and right coronary (67%{+-}10%, P<0.05) arteries. Similar degrees of regional heterogeneity were not observed in normals. Thus, while overall energy production through oxidative metabolism remains unaffected, cardiac utilisation of glucose in the fasting state is increased in the absence of catecholamine uptake sites. Innervated myocardium, however, may preferentially utilise free fatty acids, suggesting a role for sympathetic tone in

  19. Junction flow: numerical scheme assessment and grid convergence study

    International Nuclear Information System (INIS)

    The predictive capabilities of a structured and an unstructured code, both solving the incompressible RANS equations by means of the artificial compressibility formulation, are contrasted by reference to a complex three-dimensional flow past a wing-body junction for which detailed experimental data are available through the ERCOFTAC database. The structured code adopts a finite volume (FV), cell-centered formulation while the unstructured code uses residual distribution (RD) schemes and a vertex centered storage of the unknowns. The use of common grids, boundary conditions and turbulence model allows to draw conclusions on the relative performances of the two formulations, structured FV vs. unstructured RD, with respect to issues such as: computational efficiency, order of convergence, accuracy on coarse meshes. To this end, the GCI index proposed by Roache is used as a quantitative measure. (author)

  20. The Utility of Cerebral Blood Flow Assessment in TBI.

    Science.gov (United States)

    Akbik, Omar S; Carlson, Andrew P; Krasberg, Mark; Yonas, Howard

    2016-08-01

    Over the past few decades, intracranial monitoring technologies focused on treating and preempting secondary injury after traumatic brain injury (TBI) have experienced considerable growth. A physiological measure fundamental to the management of these patients is cerebral blood flow (CBF), which may be determined directly or indirectly. Direct measurement has proven difficult previously; however, invasive and non-invasive CBF monitors are now available. This article reviews the history of CBF measurements in TBI as well as the role of CBF in pathologies associated with TBI, such as cerebral autoregulation, hyperemia, and cortical spreading depression. The limitations of various CBF monitors are reviewed in order to better understand their role in TBI management. PMID:27315250

  1. Computational modeling of cardiac hemodynamics: Current status and future outlook

    Science.gov (United States)

    Mittal, Rajat; Seo, Jung Hee; Vedula, Vijay; Choi, Young J.; Liu, Hang; Huang, H. Howie; Jain, Saurabh; Younes, Laurent; Abraham, Theodore; George, Richard T.

    2016-01-01

    The proliferation of four-dimensional imaging technologies, increasing computational speeds, improved simulation algorithms, and the widespread availability of powerful computing platforms is enabling simulations of cardiac hemodynamics with unprecedented speed and fidelity. Since cardiovascular disease is intimately linked to cardiovascular hemodynamics, accurate assessment of the patient's hemodynamic state is critical for the diagnosis and treatment of heart disease. Unfortunately, while a variety of invasive and non-invasive approaches for measuring cardiac hemodynamics are in widespread use, they still only provide an incomplete picture of the hemodynamic state of a patient. In this context, computational modeling of cardiac hemodynamics presents as a powerful non-invasive modality that can fill this information gap, and significantly impact the diagnosis as well as the treatment of cardiac disease. This article reviews the current status of this field as well as the emerging trends and challenges in cardiovascular health, computing, modeling and simulation and that are expected to play a key role in its future development. Some recent advances in modeling and simulations of cardiac flow are described by using examples from our own work as well as the research of other groups.

  2. Doppler Assessment of Uterine Blood Flow in Recurrent Pregnancy Loss

    Directory of Open Access Journals (Sweden)

    Maryam Barzin

    2011-05-01

    Full Text Available Recurrent spontaneous abortion affects 2%-5% of"ncouples. Uterine perfusion is considered as one of the"nfactors that influences the success of implantation."nDuring the normal menstrual cycle, the impedance"nto uterine artery blood flow diminishes progressively"nduring the luteal phase, reaching the lowest values"nin the period coinciding with the implantation time."nImpedance of uterine arteries is a good indicator of"nthe possibility of a subsequent pregnancy. High blood"nflow resistance is associated with a reduced conception"nrate and women with lower pulsatility index values"nhave the highest possibility of becoming pregnant. An"nimpaired uterine perfusion could play a major role in"nthe pathogenesis of recurrent spontaneous abortion. In"nthis study, we examined sixty women with recurrent"nspontaneous abortion and a control group including"nthirty normal women with at least one previous"nuncomplicated pregnancy and without history of any"nabortion. Transvaginal sonography associated with"nDoppler flow measurement was performed during"nthe midluteal phase of a cycle in all women. The"nmeasurement of the ascending branch of both right"nand left uterine arteries was taken lateral to the cervix"nat the level of the internal os. The pulsatility and"nresistance index of both uterine arteries were calculated"nand compared in both groups. In this presentation we"nreport our finding in two groups. We also explain the"nexact method of study and present some interesting"ncases

  3. Current Roles and Future Applications of Cardiac CT: Risk Stratification of Coronary Artery Disease

    International Nuclear Information System (INIS)

    Cardiac computed tomography (CT) has emerged as a noninvasive modality for the assessment of coronary artery disease (CAD), and has been rapidly integrated into clinical cares. CT has changed the traditional risk stratification based on clinical risk to image-based identification of patient risk. Cardiac CT, including coronary artery calcium score and coronary CT angiography, can provide prognostic information and is expected to improve risk stratification of CAD. Currently used conventional cardiac CT, provides accurate anatomic information but not functional significance of CAD, and it may not be sufficient to guide treatments such as revascularization. Recently, myocardial CT perfusion imaging, intracoronary luminal attenuation gradient, and CT-derived computed fractional flow reserve were developed to combine anatomical and functional data. Although at present, the diagnostic and prognostic value of these novel technologies needs to be evaluated further, it is expected that all-in-one cardiac CT can guide treatment and improve patient outcomes in the near future

  4. Virtual histology assessment of cardiac allograft vasculopathy following introduction of everolimus--results of a multicenter trial

    DEFF Research Database (Denmark)

    Arora, Stina Jørgensen; Erikstad, I; Ueland, T;

    2012-01-01

    In this 12-month multicenter Scandinavian study, 78 maintenance heart transplant (HTx) recipients randomized to everolimus with reduced calcineurin inhibitor (CNI) exposure or continued standard CNI-therapy underwent matched virtual histology (VH) examination to evaluate morphological progression...... of cardiac allograft vasculopathy (CAV). Parallel measurement of a range of inflammatory markers was also performed. A similar rate of quantitative CAV progression was observed in the everolimus (n = 30) and standard CNI group (n = 48) (plaque index 1.9 ± 3.8% and 1.6 ± 3.9%, respectively; p = 0...

  5. Real-time cardiac metabolism assessed with hyperpolarized [1-13C]acetate in a large-animal model

    DEFF Research Database (Denmark)

    Flori, Alessandra; Liserani, Matteo; Frijia, Francesca;

    2015-01-01

    Dissolution-dynamic nuclear polarization (dissolution-DNP) for magnetic resonance (MR) spectroscopic imaging has recently emerged as a novel technique for noninvasive studies of the metabolic fate of biomolecules in vivo. Since acetate is the most abundant extra- and intracellular short-chain fatty...... acid, we focused on [1-13C]acetate as a promising candidate for a chemical probe to study the myocardial metabolism of a beating heart. The dissolution-DNP procedure of Na[1-13C]acetate for in vivo cardiac applications with a 3 T MR scanner was optimized in pigs during bolus injection of doses of up to...

  6. Impaired cardiac adrenergic innervation assessed by MIBG imaging as a predictor of treatment response in childhood dilated cardiomyopathy

    OpenAIRE

    Acar, P; Merlet, P.; Iserin, L; Bonnet, D.; Sidi, D; Syrota, A; Kachaner, J

    2001-01-01

    OBJECTIVE—To evaluate the prognostic value of metaiodobenzylguanidine (MIBG) imaging in childhood cardiomyopathy.
DESIGN—Prospective cohort study.
SETTING—Tertiary referral centre.
PATIENTS—40 children (21 boys, 19 girls; mean (SD) age, 7.0 (5.6) years) with heart failure resulting from idiopathic dilated cardiomyopathy (n = 23) or various other disorders (n = 17).
METHODS—At the initial examination, cardiac 123I-MIBG uptake and release, circulating noradrenaline (norepinephrine) concentratio...

  7. DOWNFLOW code and LIDAR technology for lava flow analysis and hazard assessment at Mount Etna

    Directory of Open Access Journals (Sweden)

    Alessandro Fornaciai

    2011-12-01

    Full Text Available The use of a lava-flow simulation (DOWNFLOW probabilistic code and airborne light detection and ranging (LIDAR technology are combined to analyze the emplacement of compound lava flow fields at Mount Etna (Sicily, Italy. The goal was to assess the hazard posed by lava flows. The LIDAR-derived time series acquired during the 2006 Mount Etna eruption records the changing topography of an active lava-flow field. These short-time-interval, high-resolution topographic surveys provide a detailed quantitative picture of the topographic changes. The results highlight how the flow field evolves as a number of narrow (5-15 m wide disjointed flow units that are fed simultaneously by uneven lava pulses that advance within formed channels. These flow units have widely ranging advance velocities (3-90 m/h. Overflows, bifurcations and braiding are also clearly displayed. In such a complex scenario, the suitability of deterministic codes for lava-flow simulation can be hampered by the fundamental difficulty of measuring the flow parameters (e.g. the lava discharge rate, or the lava viscosity of a single flow unit. However, the DOWNFLOW probabilistic code approaches this point statistically and needs no direct knowledge of flow parameters. DOWNFLOW intrinsically accounts for complexities and perturbations of lava flows by randomly varying the pre-eruption topography. This DOWNFLOW code is systematically applied here over Mount Etna, to derive a lava-flow hazard map based on: (i the topography of the volcano; (ii the probability density function for vent opening; and (iii a law for the expected lava-flow length for all of the computational vents considered. Changes in the hazard due to the recent morphological evolution of Mount Etna have also been addressed.

  8. Assessment of cardiac troponin I in patients with pulmonary emboli and its relationship with right ventricular dysfunction

    Directory of Open Access Journals (Sweden)

    Sasan Tavana

    2009-01-01

    Full Text Available (Received 16 December, 2008; Accepted 27 May, 2009AbstractBackground and purpose: Right ventricular dysfunction is common in major pulmonary embolisms. The purpose of this study was to evaluate the prevalence and diagnostic utility of cardiac troponin I and also to identify patients with RV dysfunction in pulmonary embolism.Materials and methods: This study was conducted on 42 patients with pulmonary embolism in Ekbatan Hospital, in Hamedan city. Data from history, echocardiogram, and lung perfusion scan was obtained from medical records. Blood samples were obtained immediately after pulmonary embolism was diagnosed. Cardiac troponin was measured using chromatographic assay.Results: Two patients (4.8% had positive troponin I (≥0.5µg/l, and 40 patients (95.2% had negative troponin I (0.05. Conclusion: Our data demonstrates that troponin I measurement is not able to distinguish specifically between coronary and non- coronary causes of chest pain.J Mazand Univ Med Sci 2009; 19(70: 72-75 (Persian

  9. Non-invasive assessment of the left ventricular pressure to volume relationships during ejection period using a single cardiac probe system and tonometric measurement of radial arterial pressure

    International Nuclear Information System (INIS)

    The left ventricular (LV) pressure to volume relationships are very sensitive parameters for the evaluation of the LV function. For measurement of LV pressure in an entire cardiac cycle, an invasive method is always needed. However, on the assumption that the LV pressure is similar to that of aorta and radial artery during ejection period, we have developed a new system for simple and non-invasive assessment of the LV pressure to volume relationships. The LV volume is estimated by ECG-gated radionuclide ventriculography using a single cardiac probe system and the data were collected every 10 msec. The radial arterial pressure was measured simultaneously every 10 msec by a tonometry system. These data were transferred to the personal computer through RS-232c cable. Then the pressure to volume curves during ejection phase was generated automatically. Emax was calculated from these curves. Moreover, the new parameter called the ejection rate of change of power (ERCP) can be calculated. These parameters are very useful for the evaluation of the effect of the drugs on the LV performance. (author)

  10. Aortic stiffness is associated with cardiac function and cerebral small vessel disease in patients with type 1 diabetes mellitus: assessment by magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Elderen, Saskia G.C. van; Brandts, A.; Westenberg, J.J.M.; Grond, J. van der; Buchem, M.A. van; Kroft, L.J.M.; Roos, A. de [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Tamsma, J.T.; Romijn, J.A.; Smit, J.W.A. [Leiden University Medical Center, Department of Endocrinology, Leiden (Netherlands)

    2010-05-15

    To evaluate, with the use of magnetic resonance imaging (MRI), whether aortic pulse wave velocity (PWV) is associated with cardiac left ventricular (LV) function and mass as well as with cerebral small vessel disease in patients with type 1 diabetes mellitus (DM). We included 86 consecutive type 1 DM patients (49 male, mean age 46.9 {+-} 11.7 years) in a prospective, cross-sectional study. Exclusion criteria included aortic/heart disease and general MRI contra-indications. MRI of the aorta, heart and brain was performed for assessment of aortic PWV, as a marker of aortic stiffness, systolic LV function and mass, as well as for the presence of cerebral white matter hyperintensities (WMHs), microbleeds and lacunar infarcts. Multivariate linear or logistic regression was performed to analyse the association between aortic PWV and outcome parameters, with covariates defined as age, gender, mean arterial pressure, heart rate, BMI, smoking, DM duration and hypertension. Mean aortic PWV was 7.1 {+-} 2.5 m/s. Aortic PWV was independently associated with LV ejection fraction (ss= -0.406, P = 0.006), LV stroke volume (ss=-0.407, P = 0.001), LV cardiac output (ss= -0.458, P = 0.001), and with cerebral WMHs (P < 0.05). There were no independent associations between aortic stiffness and LV mass, cerebral microbleeds or lacunar infarcts. Aortic stiffness is independently associated with systolic LV function and cerebral WMHs in patients with type 1 DM. (orig.)

  11. Aortic stiffness is associated with cardiac function and cerebral small vessel disease in patients with type 1 diabetes mellitus: assessment by magnetic resonance imaging

    International Nuclear Information System (INIS)

    To evaluate, with the use of magnetic resonance imaging (MRI), whether aortic pulse wave velocity (PWV) is associated with cardiac left ventricular (LV) function and mass as well as with cerebral small vessel disease in patients with type 1 diabetes mellitus (DM). We included 86 consecutive type 1 DM patients (49 male, mean age 46.9 ± 11.7 years) in a prospective, cross-sectional study. Exclusion criteria included aortic/heart disease and general MRI contra-indications. MRI of the aorta, heart and brain was performed for assessment of aortic PWV, as a marker of aortic stiffness, systolic LV function and mass, as well as for the presence of cerebral white matter hyperintensities (WMHs), microbleeds and lacunar infarcts. Multivariate linear or logistic regression was performed to analyse the association between aortic PWV and outcome parameters, with covariates defined as age, gender, mean arterial pressure, heart rate, BMI, smoking, DM duration and hypertension. Mean aortic PWV was 7.1 ± 2.5 m/s. Aortic PWV was independently associated with LV ejection fraction (ss= -0.406, P = 0.006), LV stroke volume (ss=-0.407, P = 0.001), LV cardiac output (ss= -0.458, P = 0.001), and with cerebral WMHs (P < 0.05). There were no independent associations between aortic stiffness and LV mass, cerebral microbleeds or lacunar infarcts. Aortic stiffness is independently associated with systolic LV function and cerebral WMHs in patients with type 1 DM. (orig.)

  12. Quantification in non-invasive cardiac imaging: CT and MR

    OpenAIRE

    Rossi, Alexia

    2013-01-01

    markdownabstract__Abstract__ The diagnosis and management of cardiac disease require a precise assessment of morphological and functional cardiac parameters. This thesis is divided in three parts. Part I emphasizes the role of cardiac computed tomography (CT) in the diagnosis of patients with ischemic heart disease. Part 2 describes the role of cardiac magnetic resonance (CMR) and cardiac CT in the diagnosis, interventional planning, and follow-up of patients with aortic valve stenosis. Part ...

  13. Chemical exergy assessment of organic matter in a water flow

    International Nuclear Information System (INIS)

    In recent years, exergy analysis has been successfully applied to natural resources assessment. The consumption of any natural resource is unavoidably joined to dispersion and degradation. Therefore, exergy analysis can be applied to study the depletion of natural resources and, particularly, to water resources. Different studies range from global fresh water resources evaluation to specific water bodies' detailed analysis. Physical Hydronomics is a new approach based on the specific application of Thermodynamics to physically characterize the state of a river and to help in the Governance of water bodies. The core task in the methodology is the construction of the exergy profiles of the river and it requires the calculation of the different specific exergy components in the water body: potential, thermal, mechanical, kinetic and chemical exergy. This paper is focused on the exergy assessment for the organic chemical matter present in water bodies. Different parameters such as chemical oxygen demand (COD), biological oxygen demand (BOD) or total organic carbon (TOC), among others, can be used as raw data for the calculation. Starting from available sampling data, previous approaches are analyzed, completed and compared. The well-known and most simple average molecule representing the organic matter in the river (CH2O) is proposed. Results show that, considering surface waters, TOC parameter is the most convenient one, but also that the BOD and COD can be reasonably useful.

  14. Numerical assessment of the influence of long-term topographic change on deep groundwater flow conditions

    International Nuclear Information System (INIS)

    It is important to understand how long-term geological phenomena such as uplift and erosion influence deep hydrogeological and hydrochemical environments, and to predict the influence of such long-term geological phenomena in the future for the geological disposal of nuclear wastes. From the viewpoint of groundwater flow, it is necessary to estimate long-term topographic changes, and to evaluate their influence on deep groundwater flow conditions. In this study, the influence of long-term topographic change on deep groundwater flow conditions was numerically assessed. The general paleotopographic features of a wide area were estimated and groundwater flow simulations were carried out around the Tono area. As a result, the effects of long-term topographic changes and hydraulic features of faults on groundwater flow conditions, such as hydraulic gradient, velocity distribution, flow paths, and lengths, were confirmed. In general, if topographic characteristics such as locations of major mountains and valleys around the site have not changed, the groundwater flow paths will not significantly change. The methodology, which is proposed in this study, used to understand groundwater flow evolutions due to long-term topographic changes is efficient for identifying detailed assessment areas and is recommended based on the results of this study. (author)

  15. Trends in Flow-based Biosensing Systems for Pesticide Assessment

    Directory of Open Access Journals (Sweden)

    Jean-Louis Marty

    2006-10-01

    Full Text Available This review gives a survey on the state of the art of pesticide detection usingflow-based biosensing systems for sample screening. Although immunosensor systems havebeen proposed as powerful pesticide monitoring tools, this review is mainly focused onenzyme-based biosensors, as they are the most commonly employed when using a flowsystem. Among the different detection methods able to be integrated into flow-injectionanalysis (FIA systems, the electrochemical ones will be treated in more detail, due to theirhigh sensitivity, simple sample pretreatment, easy operational procedures and real-timedetection. During the last decade, new trends have been emerging in order to increase theenzyme stability, the sensitivity and selectivity of the measurements, and to lower thedetection limits. These approaches are based on (i the design of novel matrices for enzymeimmobilisation, (ii new manifold configurations of the FIA system, sometimes includingminiaturisation or lab-on-chip protocols thanks to micromachining technology, (iii the useof cholinesterase enzymes either from various commercial sources or genetically modifiedwith the aim of being more sensitive, (iv the incorporation of other highly specificenzymes, such as organophosphate hydrolase (OPH or parathion hydrolase (PH and (v thecombination of different electrochemical methods of detection. This article discusses thesenovel strategies and their advantages and limitations.

  16. A flow cytometric approach to assess phytoplankton respiration.

    Science.gov (United States)

    Grégori, Gérald; Denis, Michel; Lefèvre, Dominique; Beker, Beatriz

    2002-01-01

    Microbial respiration in the ocean is considered as the major process representative of the organic matter biological oxidation. The corresponding metabolic CO2 production was estimated to be about 22 Pg C y(-1). However, the in situ respiration rate is generally too low (by several orders of magnitude) to be accessible to the available direct measurement methods. Some fluorescent probes, such as DiOC6(3) (Molecular Probes, USA) have been shown to be very sensitive to changes in the proton electrochemical potential difference (DeltamuH+), characterising mitochondrial and plasmic membranes bearing the cell respiratory system in eukaryotic and prokaryotic cells respectively. In mitochondria, DeltamuH+ is linked to the flux of oxygen uptake by a linear relationship. To our knowledge, no such relationship has been established in the case of whole marine cells. In the present work, we addressed the dark respiration rate of the Chlorophyceae Dunaliella tertiolecta (Butcher) in axenic cultures, both directly by using a highly sensitive oxygraph (Oroboros) and by staining cells with DiOC6(3). We found and standardized a linear relationship between oxygen uptake by D. tertiolecta and its green fluorescence induced by DiOC6(3), enabling the determination by flow cytometry of the respiration rate of D. tertiolecta. PMID:12815298

  17. QUAliFiER: An automated pipeline for quality assessment of gated flow cytometry data

    Directory of Open Access Journals (Sweden)

    Finak Greg

    2012-09-01

    Full Text Available Abstract Background Effective quality assessment is an important part of any high-throughput flow cytometry data analysis pipeline, especially when considering the complex designs of the typical flow experiments applied in clinical trials. Technical issues like instrument variation, problematic antibody staining, or reagent lot changes can lead to biases in the extracted cell subpopulation statistics. These biases can manifest themselves in non–obvious ways that can be difficult to detect without leveraging information about the study design or other experimental metadata. Consequently, a systematic and integrated approach to quality assessment of flow cytometry data is necessary to effectively identify technical errors that impact multiple samples over time. Gated cell populations and their statistics must be monitored within the context of the experimental run, assay, and the overall study. Results We have developed two new packages, flowWorkspace and QUAliFiER to construct a pipeline for quality assessment of gated flow cytometry data. flowWorkspace makes manually gated data accessible to BioConductor’s computational flow tools by importing pre–processed and gated data from the widely used manual gating tool, FlowJo (Tree Star Inc, Ashland OR. The QUAliFiER package takes advantage of the manual gates to perform an extensive series of statistical quality assessment checks on the gated cell sub–populations while taking into account the structure of the data and the study design to monitor the consistency of population statistics across staining panels, subject, aliquots, channels, or other experimental variables. QUAliFiER implements SVG–based interactive visualization methods, allowing investigators to examine quality assessment results across different views of the data, and it has a flexible interface allowing users to tailor quality checks and outlier detection routines to suit their data analysis needs. Conclusion We present a

  18. PET and SPET tracers for mapping the cardiac nervous system

    Energy Technology Data Exchange (ETDEWEB)

    Langer, Oliver; Halldin, Christer [Department of Clinical Neuroscience, Psychiatry Section, Karolinska Institute, Karolinska Hospital, 17176 Stockholm (Sweden)

    2002-03-01

    The human cardiac nervous system consists of a sympathetic and a parasympathetic branch with (-)-norepinephrine and acetylcholine as the respective endogenous neurotransmitters. Dysfunction of the cardiac nervous system is implicated in various types of cardiac disease, such as heart failure, myocardial infarction and diabetic autonomic neuropathy. In vivo assessment of the distribution and function of cardiac sympathetic and parasympathetic neurones with positron emission tomography (PET) and single-photon emission tomography (SPET) can be achieved by means of a number of carbon-11-, fluorine-18-, bromine-76- and iodine-123-labelled tracer molecules. Available tracers for mapping sympathetic neurones can be divided into radiolabelled catecholamines, such as 6-[{sup 18}F]fluorodopamine, (-)-6-[{sup 18}F]fluoronorepinephrine and (-)-[{sup 11}C]epinephrine, and radiolabelled catecholamine analogues, such as [{sup 123}I]meta-iodobenzylguanidine, [{sup 11}C]meta-hydroxyephedrine, [{sup 18}F]fluorometaraminol, [{sup 11}C]phenylephrine and meta-[{sup 76}Br]bromobenzylguanidine. Resistance to metabolism by monoamine oxidase and catechol-O-methyl transferase simplifies the myocardial kinetics of the second group. Both groups of compounds are excellent agents for an overall assessment of sympathetic innervation. Biomathematical modelling of tracer kinetics is complicated by the complexity of the steps governing neuronal uptake, retention and release of these agents as well as by their high neuronal affinity, which leads to partial flow dependence of uptake. Mapping of cardiac parasympathetic neurones is limited by a low density and focal distribution pattern of these neurones in myocardium. Available tracers are derivatives of vesamicol, a molecule that binds to a receptor associated with the vesicular acetylcholine transporter. Compounds like (-)-[{sup 18}F]fluoroethoxybenzovesamicol display a high degree of non-specific binding in myocardium which restricts their utility

  19. PET and SPET tracers for mapping the cardiac nervous system

    International Nuclear Information System (INIS)

    The human cardiac nervous system consists of a sympathetic and a parasympathetic branch with (-)-norepinephrine and acetylcholine as the respective endogenous neurotransmitters. Dysfunction of the cardiac nervous system is implicated in various types of cardiac disease, such as heart failure, myocardial infarction and diabetic autonomic neuropathy. In vivo assessment of the distribution and function of cardiac sympathetic and parasympathetic neurones with positron emission tomography (PET) and single-photon emission tomography (SPET) can be achieved by means of a number of carbon-11-, fluorine-18-, bromine-76- and iodine-123-labelled tracer molecules. Available tracers for mapping sympathetic neurones can be divided into radiolabelled catecholamines, such as 6-[18F]fluorodopamine, (-)-6-[18F]fluoronorepinephrine and (-)-[11C]epinephrine, and radiolabelled catecholamine analogues, such as [123I]meta-iodobenzylguanidine, [11C]meta-hydroxyephedrine, [18F]fluorometaraminol, [11C]phenylephrine and meta-[76Br]bromobenzylguanidine. Resistance to metabolism by monoamine oxidase and catechol-O-methyl transferase simplifies the myocardial kinetics of the second group. Both groups of compounds are excellent agents for an overall assessment of sympathetic innervation. Biomathematical modelling of tracer kinetics is complicated by the complexity of the steps governing neuronal uptake, retention and release of these agents as well as by their high neuronal affinity, which leads to partial flow dependence of uptake. Mapping of cardiac parasympathetic neurones is limited by a low density and focal distribution pattern of these neurones in myocardium. Available tracers are derivatives of vesamicol, a molecule that binds to a receptor associated with the vesicular acetylcholine transporter. Compounds like (-)-[18F]fluoroethoxybenzovesamicol display a high degree of non-specific binding in myocardium which restricts their utility for cardiac neuronal imaging. (orig.)

  20. Assessment of left ventricular function by gated cardiac blood-pool emission computed tomography using a rotating gamma camera

    International Nuclear Information System (INIS)

    To elucidate the usefulness of gated cardiac blood-pool single photon emission CT (SPECT) with Tc-99m for the evaluation of left ventricular (LV) global and regional functions, 18 patients with coronary artery disease were studied. Thirty-two gated projection images were obtained over 360-degree at 16 frames per cardiac cycle. As LV volume was calculated by integrating the numbers of voxels which constituted LV and multiplying by the volume of a single voxel (0.1143 ml), we performed phantom studies to determine the appropriate cut-off level to detect LV outline. These cut-off levels were affected by the background activity and organ volume itself. So we constructed Volume-Cut-Level-Curve at each background activity. In clinical studies, short axis images which constituted LV were selected and provisional LV volumes were calculated at the cut-off levels of 45, 50 and 55%. These volumes were plotted on the Volume-Cut-Level-Curve and the true cut-off levels were obtained to calculate LV end-diastolic or end-systolic volume (EDV, ESV). The cut-off levels were different at every patient and ED or ES. EDV, ESV and LV ejection fraction obtained by SPECT were correlatd well with those obtained by contrast ventriculography (LVG) (r=0.89, 0.94, 0.94 each, p<0.01). For the LV wall motion analysis, LVGs obtained at two projections were compared with SPECT or gated cardiac blood-pool planar imaging (Planar) in 5 segments. In addition to visual comparison, wall motion scores (WMS) based on the degree of wall motion abnormality were calculated in each segment. Correlation of WMS between LVG and SPECT (r=0.84) was significantly (p<0.01) superior to that between LVG and Planar (r=0.62). Especially in SPECT, wall motion analyses at septal and infero-posterior segments were superior to those in Planar. Although gated SPECT requires relatively long time to perform, it is a useful method to detect LV global and regional functions. (author)

  1. Non-invasive assessment of the effect of cardiac sympathetic innervation on metabolism of the human heart

    International Nuclear Information System (INIS)

    The role of cardiac sympathetic nerves in the regulation of myocardial metabolism is not well defined. Owing to the presence of incomplete reinnervation, heart transplant recipients provide a unique model to study the effects of efferent sympathetic innervation. Using this model, we sought to determine the influence of cardiac sympathetic signals on substrate utilisation and overall oxidative metabolism. In 21 transplant recipients, positron emission tomography was applied to determine sympathetic innervation with the noradrenaline analogue carbon-11 hydroxyephedrine, oxidative metabolism with carbon-11 acetate (n=14), and glucose utilisation with fluorine-18 fluorodeoxyglucose (n=7). The reinnervated area comprised 22%±20% of the left ventricle. Oxidative metabolism was similar in denervated and reinnervated myocardium [0.06±0.01 vs 0.06±0.01/min for k(mono)], while glucose uptake was significantly higher in denervated myocardium (6.9±6.6 vs 6.0±6.2 μmol/min/100 g; P=0.03). Reinnervation mainly occurred in the territory of the left anterior descending artery, where retention of 11C-hydroxyephedrine (6.8±2.7%/min) was higher compared with territories of the left circumflex (4.1±1.7%/min; P<0.01) and right coronary (3.8±1.1%/min; P<0.01) arteries. Oxidative metabolism was similar in all three territories, but compared with the reinnervated territory of the left anterior descending artery (53%±16% of maximum), relative FDG uptake was higher in territories of the left circumflex (76%±6%, P<0.01) and right coronary (67%±10%, P<0.05) arteries. Similar degrees of regional heterogeneity were not observed in normals. Thus, while overall energy production through oxidative metabolism remains unaffected, cardiac utilisation of glucose in the fasting state is increased in the absence of catecholamine uptake sites. Innervated myocardium, however, may preferentially utilise free fatty acids, suggesting a role for sympathetic tone in substrate utilisation. (orig.)

  2. The state of the art of groundwater flow modeling for safety assessment of a radwaste repository

    International Nuclear Information System (INIS)

    In this report, we investigated the general processes to model the groundwater flow system in a fractured aquifer and the mathematical approaches to simulate it. Then, we reviewed several modeling cases of nuclear advanced nations (e.g. Switzerland, U.S., Canada, and Sweden) for simulating the groundwater flow system for safety assessment of their real or hypothetical radwaste repository. From the reviews, we introduced some requisite research items

  3. A three-pillar approach to assessing climate impacts on low flows

    OpenAIRE

    G. Laaha; Parajka, J.; Viglione, A.; Koffler, D.; K. Haslinger; Schöner, W.; Zehetgruber, J.; G. Blöschl

    2015-01-01

    The objective of this paper is to present a new strategy for assessing climate impacts on low flows and droughts. The strategy is termed a three-pillar approach as it combines different sources of information. The first pillar, trend extrapolation, exploits the temporal patterns of observed low flows and extends them into the future. The second pillar, rainfall–runoff projections uses precipitation and temperature scenarios from climate models as an input to...

  4. Quantitative Assessment of Turbulence and Flow Eccentricity in an Aortic Coarctation: Impact of Virtual Interventions.

    Science.gov (United States)

    Andersson, Magnus; Lantz, Jonas; Ebbers, Tino; Karlsson, Matts

    2015-09-01

    Turbulence and flow eccentricity can be measured by magnetic resonance imaging (MRI) and may play an important role in the pathogenesis of numerous cardiovascular diseases. In the present study, we propose quantitative techniques to assess turbulent kinetic energy (TKE) and flow eccentricity that could assist in the evaluation and treatment of stenotic severities. These hemodynamic parameters were studied in a pre-treated aortic coarctation (CoA) and after several virtual interventions using computational fluid dynamics (CFD), to demonstrate the effect of different dilatation options on the flow field. Patient-specific geometry and flow conditions were derived from MRI data. The unsteady pulsatile flow was resolved by large eddy simulation including non-Newtonian blood rheology. Results showed an inverse asymptotic relationship between the total amount of TKE and degree of dilatation of the stenosis, where turbulent flow proximal the constriction limits the possible improvement by treating the CoA alone. Spatiotemporal maps of TKE and flow eccentricity could be linked to the characteristics of the jet, where improved flow conditions were favored by an eccentric dilatation of the CoA. By including these flow markers into a combined MRI-CFD intervention framework, CoA therapy has not only the possibility to produce predictions via simulation, but can also be validated pre- and immediate post treatment, as well as during follow-up studies. PMID:26577361

  5. Assessment of the kinetic-frictional model for dense granular flow

    Institute of Scientific and Technical Information of China (English)

    Boon Ho Ng; Yulong Ding; Mojtaba Ghadiri

    2008-01-01

    This paper aims to quantitatively assess the application of kinetic-frictional model to simulate the motion of dry granular materials in dense condition, in particular, the annular shearing in Couette configuration. The weight of frictional stress was varied to study the contribution of the frictional stress in dense granular flows. The results show that the pure kinetic-theory-based computational fluid dynamics (CFD) model (without frictional stress) over-predicts the dominant solids motion of dense granular flow while adding frictional stress [Schaeffer, D. G. (1987). Instability in the evolution equations describing incompressible granular flow. Journal of Differential Equations, 66(1), 19-50] with the solids pressure of [Lun, C. KTK., Savage, S. B., Jeffrey, D. J., & Chepurniy, N. (1984). Kinetic theories for granular flow: Inelastic particles in Couette flow and slightly inelastic particles in a general flow field. Journal of Fluid Mechanics, 140, 223-256] in the CFD model improves the simulation to better conform available experimental results. The results also suggest that frictional stress transmission plays an important role in dense granular flow and should not be neglected in granular flow simulations. Compatible simulation results to the experimental data are seen by increasing the weight of frictional stress to a factor of 1.25-1.5. These improved simulation results suggest the current constitutive relations (kinetic-frictional model) need to be improved in order to better reflect the real dense granular flow.

  6. Cardiac developmental toxicity

    OpenAIRE

    Mahler, Gretchen J.; Jonathan T Butcher

    2011-01-01

    Congenital heart disease is a highly prevalent problem with mostly unknown origins. Many cases of CHD likely involve an environmental exposure coupled with genetic susceptibility, but practical and ethical considerations make nongenetic causes of CHD difficult to assess in humans. The development of the heart is highly conserved across all vertebrate species, making animal models an excellent option for screening potential cardiac teratogens. This review will discuss exposures known to cause ...

  7. Development and assessment of the CONTAIN hybrid flow solver

    International Nuclear Information System (INIS)

    A new gravitational head formulation for the treatment of stratified conditions has been developed for CONTAIN 1.2, a control volume code used primarily for the analyses of postulated accidents in nuclear power plants. The new CONTAIN formulation of gravitational heads, termed the hybrid formulation, is described. This method of calculating stratified conditions is compared with the old, average-density formulation used in code versions prior to CONTAIN 1.2. Both formulations are assessed in this report with experimental data from three large-scale experiments in which stratified conditions formed by injection of a buoyant gas were observed. In general, the hybrid formulation gives a substantially higher degree of stratification than the old formulation. For stable, fully developed stratifications, the hybrid formulation also gives much better agreement with the measured degree of stratification than the old formulation. In addition, the predicted degree of stratification is robust and not sensitive to nodalization, provided a set of nodalization guidelines are followed. However, for stratification behavior controlled by special physics not modeled in CONTAIN, such as momentum convection, plume entrainment, or bulk molecular diffusion, one should not expect good agreement with experiment unless special measures to accommodate the missing physics are taken

  8. Establishing standards and assessment criteria for ecological instream flow needs in agricultural regions of Canada.

    Science.gov (United States)

    Peters, Daniel L; Baird, Donald J; Monk, Wendy A; Armanini, David G

    2012-01-01

    Agricultural land use can place heavy demands on regional water resources, strongly influencing the quantity and timing of water flows needed to sustain natural ecosystems. The effects of agricultural practices on streamflow conditions are multifaceted, as they also contribute to the severity of impacts arising from other stressors within the river ecosystem. Thus, river scientists need to determine the quantity of water required to sustain important aquatic ecosystem components and ecological services, to support wise apportionment of water for agricultural use. It is now apparent that arbitrarily defined minimum flows are inadequate for this task because the complex habitat requirements of the biota, which underpin the structure and function of a river ecosystem, are strongly influenced by predictable temporal variations in flow. We present an alternative framework for establishing a first-level, regional ecological instream flow needs standard based on adoption of the Indicators of Hydrologic Alteration/Range of Variability Approach as a broadly applicable hydrological assessment tool, coupling this to the Canadian Ecological Flow Index which assesses ecological responses to hydrological alteration. By explicitly incorporating a new field-based ecological assessment tool for small agricultural streams, we provide a necessary verification of altered hydrology that is broadly applicable within Canada and essential to ensure the continuous feedback between the application of flow management criteria and ecological condition. PMID:22218172

  9. THE ASSESSMENT AND REDUCTION OF CARDIAC EVENTS RISK IN NONCARDIAC OPERATIONS: IS THERE A NEED FOR REVIEW OF RECOMMENDATIONS?

    Directory of Open Access Journals (Sweden)

    A. N. Sumin

    2015-09-01

    Full Text Available One of the pressing problems of modern cardiology is the cardiac complications risk evaluation and correction in noncardiac surgery. Recent international guidelines on this issue have focused on the pharmacological prevention of complications while reducing the preoperative examination and preventive revascularization. The reason for this experts position has been a series of studies DECREASE, performed in the Erasmus Medical Center (The Netherlands under the supervision of Professor D. Poldermans. However, this summer the results of these studies have found no scientific value because of the significant irregularities in their conduct. It makes to have a new look at the problem of perioperative medicine, to rethink the available scientific evidence. In this review we discussed in detail the use of beta-blockers in noncardiac surgery in view of new circumstances.

  10. Cine MR imaging-current use in cardiac diagnosis

    International Nuclear Information System (INIS)

    This paper reviews the current status of cine MR imaging of the heart with special attention to the assessment of cardiac function. Cine MR provides tomographic sectional images with clear distinction between myocardium and flowing blood, and allows accurate volumetry of the cardiac chambers at specific points of the cardiac cycle. From these volume measurements parameters for the cardiac function, such as stroke volumem, ejection fraction, regurgitant fraction and shunt volum are calculated. While determination of chamber volumes can be done using any imaging plane, regional wall motion and wall thickening are evaluated with the short axis images. These images are readily obtained by orienting the slice selective gradient perpendicular to the long axis of the left ventricle. Left ventricular meridional wall stress is also calculated from cine MR images and noninvasive measurements of peak- and end-systolic pressure. Wall stress is an indicator of myocardial function in response to after load and can be used for monitoring patients with myocardial disease, regurgitant valvular disease and hypertension, and might be used to quantitatively assess the response of these diseases to therapy. Diseases causing hypertrophy of the ventricles, such as valvular stenosis, systemic or pulmonary hypertension and hypertrophic cardiomyopathy, can be monitored with cine MR by measuring the myocardial mass. A signal void from high velocity jets is caused by regurgitant or stenotic valvular lesion as well as flow across ventricular or atrial septal defects. Measurement of the dimension of the signal void have been correlated with the severity of regurgitation and can be used for semi-quantitation of these lesions. Due to the inherent contrast between blood and myocardium, high temporal resolution, and acquisition of tomographic images encompassing the entire heart, cine MR can serve as a comprehensive cardiac imaging modality that provides quantitative evaluation of anatomy and

  11. Site-specific Vulnerability Assessment for Debris Flows: Two Case Studies

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Here the vulnerability is defined as the potential total maximum losses due to a debris flow damaging event for a specific debris flow fan. The vulnerability is classified into property vulnerability and population vulnerability. Assessment indexes include the assets of buildings, traffic facilities, lifeline works, personal properties, and land resources for property vulnerability; age, education, and wealth of the inhabitants, natural population growth rate, and population density for population vulnerability. The vulnerability is expressed as the sum of the transformed values of the losses of property and population. Two study cases with post-fact damages by historic debris flow events in Sichuan of SW China are presented.

  12. Microdialysis Assessment of Cerebral Perfusion during Cardiac Arrest, Extracorporeal Life Support and Cardiopulmonary Resuscitation in Rats – A Pilot Trial

    Science.gov (United States)

    Schober, Andreas; Warenits, Alexandra M.; Testori, Christoph; Weihs, Wolfgang; Hosmann, Arthur; Högler, Sandra; Sterz, Fritz; Janata, Andreas; Scherer, Thomas; Magnet, Ingrid A. M.; Ettl, Florian; Laggner, Anton N.; Herkner, Harald; Zeitlinger, Markus

    2016-01-01

    Cerebral metabolic alterations during cardiac arrest, cardiopulmonary resuscitation (CPR) and extracorporeal cardiopulmonary life support (ECLS) are poorly explored. Markers are needed for a more personalized resuscitation and post—resuscitation care. Aim of this study was to investigate early metabolic changes in the hippocampal CA1 region during ventricular fibrillation cardiac arrest (VF-CA) and ECLS versus conventional CPR. Male Sprague-Dawley rats (350g) underwent 8min untreated VF-CA followed by ECLS (n = 8; bloodflow 100ml/kg), mechanical CPR (n = 18; 200/min) until return of spontaneous circulation (ROSC). Shams (n = 2) were included. Glucose, glutamate and lactate/pyruvate ratio were compared between treatment groups and animals with and without ROSC. Ten animals (39%) achieved ROSC (ECLS 5/8 vs. CPR 5/18; OR 4,3;CI:0.7–25;p = 0.189). During VF-CA central nervous glucose decreased (0.32±0.1mmol/l to 0.04±0.01mmol/l; p<0.001) and showed a significant rise (0.53±0.1;p<0.001) after resuscitation. Lactate/pyruvate (L/P) ratio showed a 5fold increase (31 to 164; p<0.001; maximum 8min post ROSC). Glutamate showed a 3.5-fold increase to (2.06±1.5 to 7.12±5.1μmol/L; p<0.001) after CA. All parameters normalized after ROSC with no significant differences between ECLS and CPR. Metabolic changes during ischemia and resuscitation can be displayed by cerebral microdialysis in our VF-CA CPR and ECLS rat model. We found similar microdialysate concentrations and patterns of normalization in both resuscitation methods used. Institutional Protocol Number: GZ0064.11/3b/2011 PMID:27175905

  13. In vivo assessment of cardiac insulin resistance by nuclear probes using an iodinated tracer of glucose transport

    Energy Technology Data Exchange (ETDEWEB)

    Briat, Arnaud; Slimani, Lotfi; Perret, Pascale; Villemain, Daniele; Fagret, Daniel; Ghezzi, Catherine [INSERM, E0340, Radiopharmaceutiques Biocliniques, Grenoble (France); Univ Grenoble, Grenoble (France); Halimi, Serge [Univ Grenoble, Grenoble (France); Hopital Michallon, Service de Diabetologie, CHRU Grenoble, Grenoble (France); Demongeot, Jacques [Univ Grenoble, Grenoble (France); CNRS, UMR 5525, Grenoble (France)

    2007-11-15

    Insulin resistance, implying depressed cellular sensitivity to insulin, is a risk factor for type 2 diabetes and cardiovascular disease. This study is the first step towards the development of a technique of insulin resistance measurement in humans with a new tracer of glucose transport, [{sup 123}I]6-deoxy-6-iodo-D-glucose (6DIG). We investigated 6DIG kinetics in anaesthetised control rats and in three models of insulin-resistant rats: fructose fed, Zucker and ZDF. The study of myocardial 6DIG activity was performed under two conditions: first, 6DIG was injected under the baseline condition and then it was injected after a bolus injection of insulin. After each injection, radioactivity was measured over 45 min by external detection via NaI probes, in the heart and blood. A tri-compartment model was developed to obtain fractional transfer coefficients of 6DIG from the blood to the heart. These coefficients were significantly increased with insulin in control rats and did not change significantly in insulin-resistant rats. The ratio of the coefficient obtained under insulin to that obtained under basal conditions gave an index of cardiac insulin resistance for each animal. The mean values of these ratios were significantly lower in insulin-resistant than in control rats: 1.16 {+-} 0.06 vs 2.28 {+-} 0.18 (p < 0.001) for the fructose-fed group, 0.92 {+-} 0.05 vs 1.62 {+-} 0.25 (p < 0.01) for the Zucker group and 1.34 {+-} 0.06 vs 2.01 {+-} 0.26 (p < 0.05) for the ZDF group. These results show that 6DIG could be a useful tracer to image cardiac insulin resistance. (orig.)

  14. In vivo assessment of cardiac insulin resistance by nuclear probes using an iodinated tracer of glucose transport

    International Nuclear Information System (INIS)

    Insulin resistance, implying depressed cellular sensitivity to insulin, is a risk factor for type 2 diabetes and cardiovascular disease. This study is the first step towards the development of a technique of insulin resistance measurement in humans with a new tracer of glucose transport, [123I]6-deoxy-6-iodo-D-glucose (6DIG). We investigated 6DIG kinetics in anaesthetised control rats and in three models of insulin-resistant rats: fructose fed, Zucker and ZDF. The study of myocardial 6DIG activity was performed under two conditions: first, 6DIG was injected under the baseline condition and then it was injected after a bolus injection of insulin. After each injection, radioactivity was measured over 45 min by external detection via NaI probes, in the heart and blood. A tri-compartment model was developed to obtain fractional transfer coefficients of 6DIG from the blood to the heart. These coefficients were significantly increased with insulin in control rats and did not change significantly in insulin-resistant rats. The ratio of the coefficient obtained under insulin to that obtained under basal conditions gave an index of cardiac insulin resistance for each animal. The mean values of these ratios were significantly lower in insulin-resistant than in control rats: 1.16 ± 0.06 vs 2.28 ± 0.18 (p < 0.001) for the fructose-fed group, 0.92 ± 0.05 vs 1.62 ± 0.25 (p < 0.01) for the Zucker group and 1.34 ± 0.06 vs 2.01 ± 0.26 (p < 0.05) for the ZDF group. These results show that 6DIG could be a useful tracer to image cardiac insulin resistance. (orig.)

  15. Assessment of Average Tracer Concentration Approach for Flow Rate Measurement and Field Calibration

    Directory of Open Access Journals (Sweden)

    P. Sidauruk

    2015-12-01

    Full Text Available Tracer method is one of the methods available for open channel flow rate measurements such as in irrigation canals. Average tracer concentration approach is an instantaneous injection method that based on the average tracer concentrations value at the sampling point. If the procedures are correct and scientific considerations are justified, tracer method will give relatively high accuracy of measurements. The accuracy of the average tracer concentration approach has been assessed both in laboratory and field. The results of accuracy tests of open channel flow that has been conducted at the Center for Application Isotopes and Radiation Laboratory-BATAN showed that the accuracy level of average concentrations approach method was higher than 90% compared to the true value (volumetric flow rate. The accuracy of average tracer concentration approach was also assessed during the application of the method to measure flow rate of Mrican irrigation canals as an effort to perform field calibration of existing weirs. Both average tracer concentration approach and weirs can predict the trend of the flow correctly. However, it was observed that flow discrepancies between weirs measurement and average tracer concentration approach predictions were as high as 27%. The discrepancies might be due to the downgrading performances of the weirs because of previous floods and high sediment contents of the flow

  16. Assessment of flow regime alterations over a spectrum of temporal scales using wavelet-based approaches

    Science.gov (United States)

    Wu, Fu-Chun; Chang, Ching-Fu; Shiau, Jenq-Tzong

    2015-05-01

    The full range of natural flow regime is essential for sustaining the riverine ecosystems and biodiversity, yet there are still limited tools available for assessment of flow regime alterations over a spectrum of temporal scales. Wavelet analysis has proven useful for detecting hydrologic alterations at multiple scales via the wavelet power spectrum (WPS) series. The existing approach based on the global WPS (GWPS) ratio tends to be dominated by the rare high-power flows so that alterations of the more frequent low-power flows are often underrepresented. We devise a new approach based on individual deviations between WPS (DWPS) that are root-mean-squared to yield the global DWPS (GDWPS). We test these two approaches on the three reaches of the Feitsui Reservoir system (Taiwan) that are subjected to different classes of anthropogenic interventions. The GDWPS reveal unique features that are not detected with the GWPS ratios. We also segregate the effects of individual subflow components on the overall flow regime alterations using the subflow GDWPS. The results show that the daily hydropeaking waves below the reservoir not only intensified the flow oscillations at daily scale but most significantly eliminated subweekly flow variability. Alterations of flow regime were most severe below the diversion weir, where the residual hydropeaking resulted in a maximum impact at daily scale while the postdiversion null flows led to large hydrologic alterations over submonthly scales. The smallest impacts below the confluence reveal that the hydrologic alterations at scales longer than 2 days were substantially mitigated with the joining of the unregulated tributary flows, whereas the daily-scale hydrologic alteration was retained because of the hydropeaking inherited from the reservoir releases. The proposed DWPS approach unravels for the first time the details of flow regime alterations at these intermediate scales that are overridden by the low-frequency high-power flows when

  17. An Optical Flow-Based Full Reference Video Quality Assessment Algorithm.

    Science.gov (United States)

    K, Manasa; Channappayya, Sumohana S

    2016-06-01

    We present a simple yet effective optical flow-based full-reference video quality assessment (FR-VQA) algorithm for assessing the perceptual quality of natural videos. Our algorithm is based on the premise that local optical flow statistics are affected by distortions and the deviation from pristine flow statistics is proportional to the amount of distortion. We characterize the local flow statistics using the mean, the standard deviation, the coefficient of variation (CV), and the minimum eigenvalue ( λ min ) of the local flow patches. Temporal distortion is estimated as the change in the CV of the distorted flow with respect to the reference flow, and the correlation between λ min of the reference and of the distorted patches. We rely on the robust multi-scale structural similarity index for spatial quality estimation. The computed temporal and spatial distortions, thus, are then pooled using a perceptually motivated heuristic to generate a spatio-temporal quality score. The proposed method is shown to be competitive with the state-of-the-art when evaluated on the LIVE SD database, the EPFL Polimi SD database, and the LIVE Mobile HD database. The distortions considered in these databases include those due to compression, packet-loss, wireless channel errors, and rate-adaptation. Our algorithm is flexible enough to allow for any robust FR spatial distortion metric for spatial distortion estimation. In addition, the proposed method is not only parameter-free but also independent of the choice of the optical flow algorithm. Finally, we show that the replacement of the optical flow vectors in our proposed method with the much coarser block motion vectors also results in an acceptable FR-VQA algorithm. Our algorithm is called the flow similarity index. PMID:27093720

  18. Cardiac imaging assessment of the left ventricular ejection fraction%心脏影像学对左室射血分数的评估

    Institute of Scientific and Technical Information of China (English)

    丁磊; 范大立

    2012-01-01

    Left ventricular ejection fraction ( LVEF) is the most important measurement of the left ventricular function and the most commonly used parameter in clinical cardiac imaging. LVEF can be measured with different cardiac imaging techniques; left ventricular contrast angiography by catheterization, echocardiography, radionuclide ventriculography, cardiac magnetic resonance imaging and cardiac computed tomography. In this article, we reviewed the specifics of each of the cardiac imaging modality, their strength and pitfalls. We also compared the consistency and variance between them. The selection of a specific cardiac imaging modality in clinical practice should depend on the indications, local expertise and the historic data of the patient. In general, these cardiac imaging modalities correlate well, but the variance and standard deviation are large so the measurement numbers should not be used interchangeably.

  19. Assessment of myocardial changes in athletes with native T1 mapping and cardiac functional evaluation using 3 T MRI.

    Science.gov (United States)

    Görmeli, Cemile Ayşe; Görmeli, Gökay; Yağmur, Jülide; Özdemir, Zeynep Maraş; Kahraman, Ayşegül Sağır; Çolak, Cemil; Özdemir, Ramazan

    2016-06-01

    Intensive physical exercise leads to increases in left ventricular muscle mass and wall thickness. Cardiac magnetic resonance imaging allows the assessment of functional and morphological changes in an athlete's heart. In addition, a native T1 mapping technique has been suggested as a non-contrast method to detect myocardial fibrosis. The aim of this study was to show the correlation between athletes' cardiac modifications and myocardial fibrosis with a native T1 mapping technique. A total of 41 healthy non-athletic control subjects and 46 athletes underwent CMR imaging. After the functional and morphological assessments, native T1 mapping was performed in all subjects using 3.0 T magnetic resonance imaging. Most of the CMR findings were significantly higher in athletes who had ≥5 years of sports activity when compared with non-athletic controls and athletes who had <5 years of sports activity. Significantly higher results were shown in native T1 values in athletes who had <5 years of sports activity, but there were no significant differences in the left ventricular end-diastolic volume, left ventricular end-diastolic mass, or interventricular septal wall thickness between non-athletic controls and athletes who had <5 years of sports activity. The native T1 mapping technique has the potential to discriminate myocardial fibrotic changes in athletes when compared to a normal myocardium. The T1 mapping method might be a feasible technique to evaluate athletes because it does not involve contrast, is non-invasive and allows for easy evaluation of myocardial remodeling. PMID:26920720

  20. Major prognostic impact of persistent microvascular obstruction as assessed by contrast-enhanced cardiac magnetic resonance in reperfused acute myocardial infarction

    International Nuclear Information System (INIS)

    The aim of this study was to compare the prognostic significance of microvascular obstruction (MO) and persistent microvascular obstruction (PMO) as assessed by cardiac magnetic resonance (CMR) in patients with acute myocardial infarction (AMI). CMR was performed in 184 patients within the week following successfully reperfused first AMI. First-pass images were performed to evaluate extent of MO and late gadolinium-enhanced images to assess PMO and infarct size (IS). Major adverse cardiac events (MACE) were collected at 1-year follow-up. MO and PMO were found in 127 (69%) and 87 (47%) patients, respectively. By using univariate logistic regression analysis, high Global Registry of Acute Coronary Events (GRACE) risk score (odds ratio [OR] 95% confidence interval [CI]: 3.6 [1.8-7.4], p < 0.001), IS greater than 10% (OR [95% CI]: 2.7 [1.1-6.9], p = 0.036), left ventricular ejection fraction less than 40% (OR [95% CI]: 2.4 [1.1-5.2], p = 0.027), presence of MO (OR [95% CI]: 3.1 [1.3-7.3], p = 0.004) and presence of PMO (OR [95% CI]:10 [4.1-23.9], p < 0.001) were shown to be significantly associated with the outcome. By using multivariate analysis, presence of MO (OR [95% CI]: 2.5 [1.0-6.2], p = 0.045) or of PMO (OR [95% CI]: 8.7 [3.6-21.1], p < 0.001), associated with GRACE score, were predictors of MACE. Presence of microvascular obstruction and persistent microvascular obstruction is very common in AMI patients even after successful reperfusion and is associated with a dramatically higher risk of subsequent cardiovascular events, beyond established prognostic markers. Moreover, our data suggest that the prognostic impact of PMO might be superior to MO. (orig.)

  1. Assessment of hydraulic performance and biocompatibility of a MagLev centrifugal pump system designed for pediatric cardiac or cardiopulmonary support.

    Science.gov (United States)

    Dasse, Kurt A; Gellman, Barry; Kameneva, Marina V; Woolley, Joshua R; Johnson, Carl A; Gempp, Thomas; Marks, John D; Kent, Stella; Koert, Andrew; Richardson, J Scott; Franklin, Steve; Snyder, Trevor A; Wearden, Peter; Wagner, William R; Gilbert, Richard J; Borovetz, Harvey S

    2007-01-01

    The treatment of children with life-threatening cardiac and cardiopulmonary failure is a large and underappreciated public health concern. We have previously shown that the CentriMag is a magnetically levitated centrifugal pump system, having the utility for treating adults and large children (1,500 utilized worldwide). We present here the PediVAS, a pump system whose design was modified from the CentriMag to meet the physiological requirements of young pediatric and neonatal patients. The PediVAS is comprised of a single-use centrifugal blood pump, reusable motor, and console, and is suitable for right ventricular assist device (RVAD), left ventricular assist device (LVAD), biventricular assist device (BVAD), or extracorporeal membrane oxygenator (ECMO) applications. It is designed to operate without bearings, seals and valves, and without regions of blood stasis, friction, or wear. The PediVAS pump is compatible with the CentriMag hardware, although the priming volume was reduced from 31 to 14 ml, and the port size reduced from 3/8 to (1/4) in. For the expected range of pediatric flow (0.3-3.0 L/min), the PediVAS exhibited superior hydraulic efficiency compared with the CentriMag. The PediVAS was evaluated in 14 pediatric animals for up to 30 days, demonstrating acceptable hydraulic function and hemocompatibility. The current results substantiate the performance and biocompatibility of the PediVAS cardiac assist system and are likely to support initiation of a US clinical trial in the future. PMID:18043164

  2. Endogenous resident c-Kit cardiac stem cells increase in mice with an exercise-induced, physiologically hypertrophied heart

    Directory of Open Access Journals (Sweden)

    Camila Ferreira Leite

    2015-07-01

    Full Text Available Physical activity evokes well-known adaptations in the cardiovascular system. Although exercise training induces cardiac remodeling, whether multipotent stem cells play a functional role in the hypertrophic process remains unknown. To evaluate this possibility, C57BL/6 mice were subjected to swimming training aimed at achieving cardiac hypertrophy, which was morphologically and electrocardiographically characterized. Subsequently, c-Kit+Lin− and Sca-1+Lin− cardiac stem cells (CSCs were quantified using flow cytometry while cardiac muscle-derived stromal cells (CMSCs, also known as cardiac-derived mesenchymal stem cells were assessed using in vitro colony-forming unit fibroblast assay (CFU-F. Only the number of c-Kit+Lin− cells increased in the hypertrophied heart. To investigate a possible extracardiac origin of these cells, a parabiotic eGFP transgenic/wild-type mouse model was used. The parabiotic pairs were subjected to swimming, and the wild-type heart in particular was tested for eGFP+ stem cells. The results revealed a negligible number of extracardiac stem cells in the heart, allowing us to infer a cardiac origin for the increased amount of detected c-Kit+ cells. In conclusion, the number of resident Sca-1+Lin− cells and CMSCs was not changed, whereas the number of c-Kit+Lin− cells was increased during physiological cardiac hypertrophy. These c-Kit+Lin− CSCs may contribute to the physiological cardiac remodeling that result from exercise training.

  3. Magnetic resonance imaging of congenital cardiac abnormalities

    International Nuclear Information System (INIS)

    Magnetic resonance imaging will not replace echocardiography as the simplest and most definitive method of establishing a noninvasive diagnosis in young patients with congenital cardiac malformations, nor will it replace radionuclide angiography for relatively noninvasive detection and quantitation of cardiac shunts. Magnetic resonance imaging is a complementary noninvasive imaging procedure that can answer some questions left in doubt by echocardiography (mainly extracardiac artery and vein assessments) or radionuclide angiography and used as a preferred follow-up imaging method in certain clinical circumstances. In addition, MRI can be a first-line modality for cardiovascular imaging in older patients in whom adequate echo windows are not available. Angiocardiography remains necessary to provide vital physiological data, i.e., chamber pressures, shunt volumes, oxygen saturations, and pulmonary vascular resistance; however, MRI could negate some follow-up catheterizations in appropriate clinical circumstances. High-resolution proton MRI tomography should ultimately permit the accurate evaluation of ventricular volumes, myocardial mass, and the assessment of regional wall motion and ejection fractions. Paramagnetic substances such as manganese ion may ultimately provide a basis for myocardial perfusion imaging. The potential for MRI evaluation of tissue characterization, noninvasive blood-flow measurements, and myocardial metabolism assessment in intriguing and awaits clinical evaluation

  4. Cardiac rhabdomyosarcoma

    OpenAIRE

    Chlumský, Jaromír; Holá, Dana; Hlaváček, Karel; Michal, Michal; Švec, Alexander; Špatenka, Jaroslav; Dušek, Jan

    2001-01-01

    Cardiac sarcoma is a very rare neoplasm and is difficult to diagnose. The case of a 51-year-old man with a left atrial tumour, locally recurrent three months after its surgical removal, is presented. Computed tomography showed metastatic spread to the lung parenchyma. On revised histology, the mass extirpated was a sarcoma. Because of the metastatic spread, further therapy was symptomatic only; the patient died 15 months after the first manifestation of his problems. Immunohistochemical stain...

  5. Cardiac Calcification

    Directory of Open Access Journals (Sweden)

    Morteza Joorabian

    2011-05-01

    Full Text Available There is a spectrum of different types of cardiac"ncalcifications with the importance and significance"nof each type of cardiac calcification, especially"ncoronary artery calcification. Radiologic detection of"ncalcifications within the heart is quite common. The"namount of coronary artery calcification correlates"nwith the severity of coronary artery disease (CAD."nCalcification of the aortic or mitral valve may indicate"nhemodynamically significant valvular stenosis."nMyocardial calcification is a sign of prior infarction,"nwhile pericardial calcification is strongly associated"nwith constrictive pericarditis. A spectrum of different"ntypes of cardiac calcifications (linear, annular,"ncurvilinear,... could be seen in chest radiography and"nother imaging modalities. So a carful inspection for"ndetection and reorganization of these calcifications"nshould be necessary. Numerous modalities exist for"nidentifying coronary calcification, including plain"nradiography, fluoroscopy, intravascular ultrasound,"nMRI, echocardiography, and conventional, helical and"nelectron-beam CT (EBCT. Coronary calcifications"ndetected on EBCT or helical CT can be quantifie,"nand a total calcification score (Cardiac Calcification"nScoring may be calculated. In an asymptomatic"npopulation and/or patients with concomitant risk"nfactors like diabetes mellitus, determination of the"npresence of coronary calcifications identifies the"npatients at risk for future myocardial infarction and"ncoronary artery disease. In patients without coronary"ncalcifications, future cardiovascular events could"nbe excluded. Therefore, detecting and recognizing"ncalcification related to the heart on chest radiography"nand other imaging modalities such as fluoroscopy, CT"nand echocardiography may have important clinical"nimplications.

  6. Triclosan: A review on systematic risk assessment and control from the perspective of substance flow analysis.

    Science.gov (United States)

    Huang, Chu-Long; Abass, Olusegun K; Yu, Chang-Ping

    2016-10-01

    Triclosan (TCS) is a broad spectrum antibacterial agent mainly used in Pharmaceutical and Personal Care Products. Its increasing use over recent decades have raised its concentration in the environment, with commonly detectable levels found along the food web-from aquatic organisms to humans in the ecosystem. To date, there is shortage of information on how to investigate TCS's systematic risk on exposed organisms including humans, due to the paucity of systematic information on TCS flows in the anthroposphere. Therefore, a more holistic approach to mass flow balancing is required, such that the systematic risk of TCS in all environmental matrices are evaluated. From the perspective of Substance Flow Analysis (SFA), this review critically summarizes the current state of knowledge on TCS production, consumption, discharge, occurrence in built and natural environments, its exposure and metabolism in humans, and also the negative effects of TCS on biota and humans. Recent risk concerns have mainly focused on TCS removal efficiencies and metabolism, but less attention is given to the effect of mass flows from source to fate during risk exposure. However, available data for TCS SFA is limited but SFA can derive logical systematic information from limited data currently available for systematic risk assessment and reduction, based on mass flow analysis. In other words, SFA tool can be used to develop a comprehensive flow chart and indicator system for the risk assessment and reduction of TCS flows in the anthroposphere, thereby bridging knowledge gaps to streamline uncertainties related to policy-making on exposure pathways within TCS flow-lines. In the final analysis, specifics on systematic TCS risk assessment via SFA, and areas of improvement on human adaptation to risks posed by emerging contaminants are identified and directions for future research are suggested. PMID:27239720

  7. Application of flow cytometry and fluorescent in situ hybridization for assessment of exposures to airborne bacteria.

    OpenAIRE

    de Lange, J L; Thorne, P. S.; Lynch, N.

    1997-01-01

    Current limitations in the methodology for enumeration and identification of airborne bacteria compromise the precision and accuracy of bioaerosol exposure assessment. In this study, flow cytometry and fluorescent in situ hybridization (FISH) were evaluated for the assessment of exposures to airborne bacteria. Laboratory-generated two-component bioaerosols in exposures chambers and complex native bioaerosols in swine barns were sampled with two types of liquid impingers (all-glass impinger-30...

  8. Development of a Fully Automated Flow Injection Analyzer Implementing Bioluminescent Biosensors for Water Toxicity Assessment

    OpenAIRE

    Constantinos Georgiou; Georgakopoulos, Dimitrios G.; Gerasimos Kremmydas; Efstathios Vasiliou; Efstratios Komaitis

    2010-01-01

    This paper describes the development of an automated Flow Injection analyzer for water toxicity assessment. The analyzer is validated by assessing the toxicity of heavy metal (Pb2+, Hg2+ and Cu2+) solutions. One hundred μL of a Vibrio fischeri suspension are injected in a carrier solution containing different heavy metal concentrations. Biosensor cells are mixed with the toxic carrier solution in the mixing coil on the way to the detector. Response registered is % inhibition of biosensor biol...

  9. Cardiac surgery outcomes.

    Science.gov (United States)

    Halpin, Linda S; Barnett, Scott D; Beachy, Jim

    2003-01-01

    Accrediting organizations and payers are demanding valid and reliable data that demonstrate the value of services. Federal agencies, healthcare industry groups, and healthcare watchdog groups are increasing the demand for public access to outcomes data. A new and growing outcomes dynamic is the information requested by prospective patients in an increasingly consumer-oriented business. Patients demand outcomes, and resources are developing to meet these demands. Physicians are increasingly confronted with requests for information about their mortality and morbidity rates, malpractice suits, and disciplinary actions received. For example, in Virginia, prospective patients have access to data provided by the nonprofit group Virginia Health Information. After numerous resolutions by the Virginia Senate since 1999, the prospective Virginia medical consumer now has access to several annual publications: Virginia Hospitals: A Consumer's Guide, 1999 Annual Report and Strategic Plan Update, and the 1999 Industry Report: Virginia Hospitals and Nursing Facilities. Consumers have access to cardiac outcomes data stratified by hospital, gender, and cardiac service line (cardiac surgery, noninvasive cardiology, and invasive cardiology). This is particularly relevant to IHI because Virginia Health Information specifically targets cardiac care. IHI has a sizable investment in cardiovascular outcomes and has found outcomes measurement and research are key to providing quality care. IHI's goal is to move from an outcomes management model to a disease management model. The hope is to incorporate all aspects of the patient's continuum of care, from preoperative and diagnostic services through cardiac interventions to postoperative rehabilitation. Furthermore, every step along the way will be supported with functional status and quality of life assessments. Although these goals are ambitious and expensive, the return on investment is high. PMID:14618772

  10. A Turkish Version of the Cardiac Patients’ Learning Needs Inventory; Patient Questionnaire (TR-CPLNI: Reliability-Validity Assessment

    Directory of Open Access Journals (Sweden)

    Nuray Enç

    2012-01-01

    Full Text Available Background: The knowledge obtained from the tools for identifying patients' educational needs may form the basis for devising an individualized cardiac educational program. New approaches should prioritize educational planning oriented towards AMI patients' educational needs.Aim: This study was designed to investigate the validity and reliability of the Turkish adaptation of The Cardiac Patients' Learning Needs Inventory(TR-CPLNI; Patient Questionnaire to determine the educational needs of patients admitted to hospital following their first MI.Methodology: The study included 143 patients (21 women, 122 men; age ≤70 years who were treated for their first MI, with recovery from the acute period without chest pain. Data were collected using a questionnaire on sociodemographic features and the Turkish version of the CPLNI. Validity studies included language and content validity. For reliability analyses, Cronbach’s alpha coefficients were calculated and, for test-retest reliability, the scale was re-administered after a two-week interval.Results: The age groups of the participants were; 30-39 years (7.0%, 40-49 years (40.6%, 50-59 years (24.5%, and 60-70 years (28.0%. Content validity index of the scale was 0.96. The overall Cronbach’s alpha coefficient was calculated as 0.96, ranging from 0.78 to 0.92 for eight subscales. Item total correlations werebetween 0.65 and 0.85 (p<0.01. The overall test-retest reliability was 0.77 (p=0.00, ranging from 0.42 to 0.75 for eight subscales. Patients admitted to the clinic determined the important subjects which they wanted to gain information as “medication information”, “anatomy and physiology of heart”, “symptom management”respectively. After being discharged, they arranged the important subjects as life-style factors, anatomy and physiology of heart, dietary information respectively. Conclusion: Our results demonstrate that the Turkish version of the CPLNI can be used as a valid and

  11. Partial scan artifact reduction (PSAR) for the assessment of cardiac perfusion in dynamic phase-correlated CT

    Energy Technology Data Exchange (ETDEWEB)

    Stenner, Philip; Schmidt, Bernhard; Bruder, Herbert; Allmendinger, Thomas; Haberland, Ulrike; Flohr, Thomas; Kachelriess, Marc [Institute of Medical Physics, Henkestrasse 91, 91052 Erlangen (Germany); Siemens AG, Healthcare Sector, Siemensstrasse 1, 91301 Forchheim (Germany); Institute of Medical Physics, Henkestrasse. 91, 91052 Erlangen (Germany)

    2009-12-15

    Purpose: Cardiac CT achieves its high temporal resolution by lowering the scan range from 2{pi} to {pi} plus fan angle (partial scan). This, however, introduces CT-value variations, depending on the angular position of the {pi} range. These partial scan artifacts are of the order of a few HU and prevent the quantitative evaluation of perfusion measurements. The authors present the new algorithm partial scan artifact reduction (PSAR) that corrects a dynamic phase-correlated scan without a priori information. Methods: In general, a full scan does not suffer from partial scan artifacts since all projections in [0, 2{pi}] contribute to the data. To maintain the optimum temporal resolution and the phase correlation, PSAR creates an artificial full scan p{sub n}{sup AF} by projectionwise averaging a set of neighboring partial scans p{sub n}{sup P} from the same perfusion examination (typically N{approx_equal}30 phase-correlated partial scans distributed over 20 s and n=1,...,N). Corresponding to the angular range of each partial scan, the authors extract virtual partial scans p{sub n}{sup V} from the artificial full scan p{sub n}{sup AF}. A standard reconstruction yields the corresponding images f{sub n}{sup P}, f{sub n}{sup AF}, and f{sub n}{sup V}. Subtracting the virtual partial scan image f{sub n}{sup V} from the artificial full scan image f{sub n}{sup AF} yields an artifact image that can be used to correct the original partial scan image: f{sub n}{sup C}=f{sub n}{sup P}-f{sub n}{sup V}+f{sub n}{sup AF}, where f{sub n}{sup C} is the corrected image. Results: The authors evaluated the effects of scattered radiation on the partial scan artifacts using simulated and measured water phantoms and found a strong correlation. The PSAR algorithm has been validated with a simulated semianthropomorphic heart phantom and with measurements of a dynamic biological perfusion phantom. For the stationary phantoms, real full scans have been performed to provide theoretical reference

  12. Preliminary assessment of cardiac short term safety and efficacy of manganese chloride for cardiovascular magnetic resonance in humans

    Directory of Open Access Journals (Sweden)

    Kalaf Jose M

    2011-01-01

    Full Text Available Abstract Background Manganese based agents are intracellular and accumulate inside myocytes allowing for different imaging strategies compared to gadolinium contrasts. While previous agents release manganese very slowly in the circulation, MnCl2 allows for rapid Mn2+ uptake in myocytes, creating a memory effect that can be potentially explored. Data on animal models are very encouraging but the safety and efficacy of this approach in humans has not yet been investigated. Therefore, our objectives were to study the safety and efficacy of a rapid infusion of manganese chloride (MnCl2 for cardiovascular magnetic resonance (CMR in humans. Methods Fifteen healthy volunteers underwent a CMR scan on a 1.5 T scanner. Before the infusion, cardiac function was calculated and images of a short axis mid-ventricular slice were obtained using a 2D and 3D gradient-echo inversion recovery (GRE-IR sequence, a phase-sensitive IR sequence and a single breath-hold segmented IR prepared steady-state precession acquisition for T1 calculations. MnCl2 was infused over three minutes at a total dose of 5 μMol/kg. Immediately after the infusion, and at 15 and 30 minutes later, new images were obtained and cardiac function re-evaluated. Results There was a significant decrease in T1 values compared to baseline, sustained up to 30 minutes after the MnCl2 infusion (pre,839 ± 281 ms; 0 min, 684 ± 99; 15 min, 714 ± 168; 30 min, 706 ± 172, P = 0.003. The 2D and 3D GRE-IR sequence showed the greatest increase in signal-to-noise ratio compared to the other sequences (baseline 6.6 ± 4.2 and 9.7 ± 5.3; 0 min, 11.3 ± 4.1 and 15.0 ± 8.7; 15 min, 10.8 ± 4.0 and 16.9 ± 10.2; 30 min, 10.6 ± 5.2 and 16.5 ± 8.3, P 2 with no major adverse events, despite all reporting transient facial flush. Conclusions In the short term, MnCl2 appears safe for human use. It effectively decreases myocardium T1, maintaining this effect for a relatively long period of time and allowing for the

  13. Applying Physically Representative Watershed Modelling to Assess Peak and Low Flow Response to Timber Harvest: Application for Watershed Assessments

    Science.gov (United States)

    MacDonald, R. J.; Anderson, A.; Silins, U.; Craig, J. R.

    2014-12-01

    Forest harvesting, insects, disease, wildfire, and other disturbances can combine with climate change to cause unknown changes to the amount and timing of streamflow from critical forested watersheds. Southern Alberta forest and alpine areas provide downstream water supply for agriculture and water utilities that supply approximately two thirds of the Alberta population. This project uses datasets from intensely monitored study watersheds and hydrological model platforms to extend our understanding of how disturbances and climate change may impact various aspects of the streamflow regime that are of importance to downstream users. The objectives are 1) to use the model output of watershed response to disturbances to inform assessments of forested watersheds in the region, and 2) to investigate the use of a new flexible modelling platform as a tool for detailed watershed assessments and hypothesis testing. Here we applied the RAVEN hydrological modelling framework to quantify changes in key hydrological processes driving peak and low flows in a headwater catchment along the eastern slopes of the Canadian Rocky Mountains. The model was applied to simulate the period from 2006 to 2011 using data from the Star Creek watershed in southwestern Alberta. The representation of relevant hydrological processes was verified using snow survey, meteorological, and vegetation data collected through the Southern Rockies Watershed Project. Timber harvest scenarios were developed to estimate the effects of cut levels ranging from 20 to 100% over a range of elevations, slopes, and aspects. We quantified changes in the timing and magnitude of low flow and high flow events during the 2006 to 2011 period. Future work will assess changes in the probability of low and high flow events using a long-term meteorological record. This modelling framework enables relevant processes at the watershed scale to be accounted in a physically robust and computational efficient manner. Hydrologic

  14. Assessment of Displacement Flow at Ketandan Creeks to Optimizing Land Use in Jember New City Housing

    Directory of Open Access Journals (Sweden)

    Entin Hidayah

    2015-11-01

    Full Text Available Displacement flow will caused a change in the flow characteristics such as flow depth, discharge, river slope and width of the river surface. If not carefully examined, it will cause the riverbed erosion, sedimentation and risk of flooding. This paper aims to assess the hydrology and hydraulics of the river flow changes in Ketandan creek in optimizing the use of land housing for Jember New City (JNC. Hydrology modelling studies conducted for the return period rainfall include a 2 year as normal discharge, and 100 year as flood condition. Simulation of flood designs used to assess changes in the flow regime in the channel and the risk of flooding with HEC-RAS program. The results of the study showed that for the flood design 3,1 m3/sec and 12,8 m3/sec will give the effect of critical water surface. In order to keep the flow of the river bed of critically needed as the drop-structure and spillway construction.

  15. Electrocardiographically Determination of Cardiac Enlargements in Dogs

    OpenAIRE

    Gönül, Remzi; OR, Mehmet Erman; DODURKA, Tamer

    2002-01-01

    In this study, the electrocardiographic parameters necessary to determine cardiac enlargements and to establish and distinguish such complaints from each other in the early stage in dogs with circulatory problems were assessed. The material of the study consisted of 33 dogs 1.5-15 years of age with cardiac enlargements determined from 140 dogs suspected of having cardiac disease based on clinical, radiographic and electrocardiographic analyses. In these dogs, 12 cases of left atrial hypert...

  16. 4D phase contrast flow imaging for in-stent flow visualization and assessment of stent patency in peripheral vascular stents – A phantom study

    International Nuclear Information System (INIS)

    Purpose: 4D phase contrast flow imaging is increasingly used to study the hemodynamics in various vascular territories and pathologies. The aim of this study was to assess the feasibility and validity of MRI based 4D phase contrast flow imaging for the evaluation of in-stent blood flow in 17 commonly used peripheral stents. Materials and methods: 17 different peripheral stents were implanted into a MR compatible flow phantom. In-stent visibility, maximal velocity and flow visualization were assessed and estimates of in-stent patency obtained from 4D phase contrast flow data sets were compared to a conventional 3D contrast-enhanced magnetic resonance angiography (CE-MRA) as well as 2D PC flow measurements. Results: In all but 3 of the tested stents time-resolved 3D particle traces could be visualized inside the stent lumen. Quality of 4D flow visualization and CE-MRA images depended on stent type and stent orientation relative to the magnetic field. Compared to the visible lumen area determined by 3D CE-MRA, estimates of lumen patency derived from 4D flow measurements were significantly higher and less dependent on stent type. A higher number of stents could be assessed for in-stent patency by 4D phase contrast flow imaging (n = 14) than by 2D phase contrast flow imaging (n = 10). Conclusions: 4D phase contrast flow imaging in peripheral vascular stents is feasible and appears advantageous over conventional 3D contrast-enhanced MR angiography and 2D phase contrast flow imaging. It allows for in-stent flow visualization and flow quantification with varying quality depending on stent type

  17. Whole-heart cine MRI in a single breath-hold. A compressed sensing accelerated 3D acquisition technique for assessment of cardiac function

    International Nuclear Information System (INIS)

    simulated dataset and the in-vivo measurement highlights the great potential of the presented technique for an efficient assessment of cardiac functional parameters. (orig.)

  18. Whole-heart cine MRI in a single breath-hold. A compressed sensing accelerated 3D acquisition technique for assessment of cardiac function

    Energy Technology Data Exchange (ETDEWEB)

    Wech, T.; Koestler, H. [Wuerzburg Univ. (Germany). Inst. of Radiology; Wuerzburg Univ. (Germany). Comprehensive Heart Failure Center; Pickl, W.; Tran-Gia, J.; Ritter, C.; Hahn, D. [Wuerzburg Univ. (Germany). Inst. of Radiology; Beer, M. [Wuerzburg Univ. (Germany). Inst. of Radiology; Graz Univ. (Austria). University Hospital Radiology

    2014-01-15

    simulated dataset and the in-vivo measurement highlights the great potential of the presented technique for an efficient assessment of cardiac functional parameters. (orig.)

  19. Video camera observation for assessing overland flow patterns during rainfall events

    Science.gov (United States)

    Silasari, Rasmiaditya; Oismüller, Markus; Blöschl, Günter

    2015-04-01

    Physically based hydrological models have been widely used in various studies to model overland flow propagation in cases such as flood inundation and dam break flow. The capability of such models to simulate the formation of overland flow by spatial and temporal discretization of the empirical equations makes it possible for hydrologists to trace the overland flow generation both spatially and temporally across surface and subsurface domains. As the upscaling methods transforming hydrological process spatial patterns from the small obrseved scale to the larger catchment scale are still being progressively developed, the physically based hydrological models become a convenient tool to assess the patterns and their behaviors crucial in determining the upscaling process. Related studies in the past had successfully used these models as well as utilizing field observation data for model verification. The common observation data used for this verification are overland flow discharge during natural rainfall events and camera observations during synthetic events (staged field experiments) while the use of camera observations during natural events are hardly discussed in publications. This study advances in exploring the potential of video camera observations of overland flow generation during natural rainfall events to support the physically based hydrological model verification and the assessment of overland flow spatial patterns. The study is conducted within a 64ha catchment located at Petzenkirchen, Lower Austria, known as HOAL (Hydrological Open Air Laboratory). The catchment land covers are dominated by arable land (87%) with small portions (13%) of forest, pasture and paved surfaces. A 600m stream is running at southeast of the catchment flowing southward and equipped with flumes and pressure transducers measuring water level in minutely basis from various inlets along the stream (i.e. drainages, surface runoffs, springs) to be calculated into flow discharge. A

  20. Multiscale entropy analysis of EEG for assessment of post-cardiac arrest neurological recovery under hypothermia in rats.

    Science.gov (United States)

    Kang, Xiaoxu; Jia, Xiaofeng; Geocadin, Romergryko G; Thakor, Nitish V; Maybhate, Anil

    2009-04-01

    Neurological complications after cardiac arrest (CA) can be fatal. Although hypothermia has been shown to be beneficial, understanding the mechanism and establishing neurological outcomes remains challenging because effects of CA and hypothermia are not well characterized. This paper aims to analyze EEG (and the alpha-rhythms) using multiscale entropy (MSE) to demonstrate the ability of MSE in tracking changes due to hypothermia and compare MSE during early recovery with long-term neurological examinations. Ten Wistar rats, upon post-CA resuscitation, were randomly subjected to hypothermia (32 degrees C-34 degrees C, N = 5) or normothermia (36.5 degrees C-37.5 degrees C, N = 5). EEG was recorded and analyzed using MSE during seven recovery phases for each experiment: baseline, CA, and five early recovery phases (R1-R5). Postresuscitation neurological examination was performed at 6, 24, 48, and 72 h to obtain neurological deficit scores (NDSs). Results showed MSE to be a sensitive marker of changes in alpha-rhythms. Significant difference (p < 0.05) was found between the MSE for two groups during recovery, suggesting that MSE can successfully reflect temperature modulation. A comparison of short-term MSE and long-term NDS suggested that MSE could be used for predicting favorability of long-term outcome. These experiments point to the role of cortical rhythms in reporting early neurological response to ischemia and therapeutic hypothermia. PMID:19174339

  1. Alternative conceptual models and codes for unsaturated flow in fractured tuff: Preliminary assessments for GWTT-95

    International Nuclear Information System (INIS)

    Groundwater travel time (GWTT) calculations will play an important role in addressing site-suitability criteria for the potential high-level nuclear waste repository at Yucca Mountain,Nevada. In support of these calculations, Preliminary assessments of the candidate codes and models are presented in this report. A series of benchmark studies have been designed to address important aspects of modeling flow through fractured media representative of flow at Yucca Mountain. Three codes (DUAL, FEHMN, and TOUGH 2) are compared in these benchmark studies. DUAL is a single-phase, isothermal, two-dimensional flow simulator based on the dual mixed finite element method. FEHMN is a nonisothermal, multiphase, multidimensional simulator based primarily on the finite element method. TOUGH2 is anon isothermal, multiphase, multidimensional simulator based on the integral finite difference method. Alternative conceptual models of fracture flow consisting of the equivalent continuum model (ECM) and the dual permeability (DK) model are used in the different codes

  2. Assessing Geomorphic and Vegetative Responses to Environmental Flows in the Willamette River Basin

    Science.gov (United States)

    Mangano, J.; Jones, K.; Wallick, R.; Bach, L.; Olson, M.; Bervid, H.

    2015-12-01

    On regulated rivers, restoring flow regimes is a process-based restoration approach that may strongly affect downstream ecosystems. Developing realistic flow targets with meaningful geomorphic and ecological benefits, however, is challenging. For instance, hydraulic, geomorphic and biological processes are affected by more than manipulating water release—sediment supply and transport conditions also require consideration. Also, funding and programmatic directives rarely require the monitoring necessary to adaptively manage environmental flow programs. Recent research in the Willamette River basin in support of the Sustainable Rivers Project (SRP) demonstrates how such a monitoring program can be implemented. At the reach scale, initial efforts have assessed geomorphic and vegetative changes in alluvial sections of the Middle Fork Willamette and McKenzie Rivers using repeat mapping from aerial photographs and flow analyses. Overall, both rivers are largely stable because of reduced discharge, bed-material supply and local revetments, but some reaches of the McKenzie River are more dynamic, perhaps reflecting greater inputs of sediment from unregulated tributaries and higher magnitude peak flows. Repeat, reach-scale mapping on the Middle Fork Willamette River shows that frequent bankfull flows are able to scour minimally vegetated gravel bars and sustain a patchwork of actively shifting bed-material sediment. Repeat mapping on the McKenzie River in summer 2015 will reveal insights about the geomorphic effectiveness of bankfull flows. At the site scale, monitoring at two bars in summer 2015 is linking streamflow with the establishment of black cottonwood. Lastly, a review of hydrographs from 2000-2015 and retrospectively applying stakeholder-defined flow targets showed substantial variability in meeting objectives for the timing and types of flows under traditional regulated conditions and the SRP. Altogether, these related efforts help link streamflow, geomorphic

  3. Impact of pericardial adhesions on diastolic function as assessed by vortex formation time, a parameter of transmitral flow efficiency

    Directory of Open Access Journals (Sweden)

    Heys Jeffrey J

    2010-09-01

    Full Text Available Abstract Background Pericardial adhesions are a pathophysiological marker of constrictive pericarditis (CP, which impairs cardiac filling by limiting the total cardiac volume compliance and diastolic filling function. We studied diastolic transmitral flow efficiency as a new parameter of filling function in a pericardial adhesion animal model. We hypothesized that vortex formation time (VFT, an index of optimal efficient diastolic transmitral flow, is altered by patchy pericardial-epicardial adhesions. Methods In 8 open-chest pigs, the heart was exposed while preserving the pericardium. We experimentally simulated early pericardial constriction and patchy adhesions by instilling instant glue into the pericardial space and using pericardial-epicardial stitches. We studied left ventricular (LV function and characterized intraventricular blood flow with conventional and Doppler echocardiography at baseline and following the experimental intervention. Results Significant decreases in end-diastolic volume, ejection fraction, stroke volume, and late diastolic filling velocity reflected the effects of the pericardial adhesions. The mean VFT value decreased from 3.61 ± 0.47 to 2.26 ± 0.45 (P = 0.0002. Hemodynamic variables indicated the inhibiting effect of pericardial adhesion on both contraction (decrease in systolic blood pressure and +dP/dt decreased and relaxation (decrease in the magnitude of -dP/dt and prolongation of Tau function. Conclusion Patchy pericardial adhesions not only negatively impact LV mechanical functioning but the decrease of VFT from normal to suboptimal value suggests impairment of transmitral flow efficiency.

  4. Assessment of the adequacy of bronchial stenting by flow-volume loops

    Energy Technology Data Exchange (ETDEWEB)

    McLaren, Clare A.; Roebuck, Derek J. [Great Ormond Street Hospital for Children, Department of Radiology, London (United Kingdom); Pigott, Nick; Elliott, Martin J. [Great Ormond Street Hospital for Children, Cardiothoracic Unit, London (United Kingdom); Dunne, Catherine [Great Ormond Street Hospital for Children, Department of Physiotherapy, London (United Kingdom)

    2006-08-15

    Airway compression is a common problem in children with certain forms of congenital heart disease. Although various surgical approaches are available to overcome this form of airway obstruction, internal stenting is necessary in a minority of patients. It can be difficult to assess the success of stenting at the time of the procedure, and the interval to successful extubation is usually used as an outcome measure. Measurement of relevant parameters of respiratory physiology with flow-volume and volume-pressure loops permits immediate quantitative assessment of the adequacy of stenting. A 3-month-old infant who underwent bronchial stenting and physiological assessment at the time of the procedure is described. (orig.)

  5. Assessment of intermittent two-phase flow using a high-speed visualization technique

    International Nuclear Information System (INIS)

    The intermittent two-phase horizontal flow is recognized by many authors to be one of the most highly complex inherently unsteady flow pattern. Great efforts have been made in recent years to develop theoretical models to predict the intermittent flow interfacial parameters. However, as far as the flow structure itself is concerned, these models are not capable to predicting them yet. The liquid slug and gas bubble velocity, length and evolution along the flow are examples of structural parameters that require experimental specialised work to their evaluation. In this paper, we describe the application of a visualization technique to assess the intermittent two-phase air-water horizontal flow. The technique consists in employing a high-speed digital camera to take a series of pictures of the bubbles moving in the upper side of a horizontal pipe, where a gas-liquid mixture flows. From the images obtained the bubbles can be tracked along. Analyzing frame by frame it is possible to extract the gas bubbles lengths and velocities. This investigation is restricted to liquid superficial velocities ranging from 0.3 to 2.0 m/s and to gas superficial velocities ranging from 0.1 to 1.6 m/s. (author)

  6. The New York State cardiac registries: history, contributions, limitations, and lessons for future efforts to assess and publicly report healthcare outcomes.

    Science.gov (United States)

    Hannan, Edward L; Cozzens, Kimberly; King, Spencer B; Walford, Gary; Shah, Nirav R

    2012-06-19

    In 1988, the New York State Health Commissioner was confronted with hospital-level data demonstrating very large, multiple-year, interhospital variations in short-term mortality and complications for cardiac surgery. The concern with the extent to which these differences were due to variations in patients' pre-surgical severity of illness versus hospitals' quality of care led to the development of clinical registries for cardiac surgery in 1989 and for percutaneous coronary interventions in 1992 in New York. In 1990, the Department of Health released hospitals' risk-adjusted cardiac surgery mortality rates for the first time, and shortly thereafter, similar data were released for hospitals and physicians for percutaneous coronary interventions, cardiac valve surgery, and pediatric cardiac surgery (only hospital data). This practice is still ongoing. The purpose of this communication is to relate the history of this initiative, including changes or purported changes that have occurred since the public release of cardiac data. These changes include decreases in risk-adjusted mortality, cessation of cardiac surgery in New York by low-volume and high-mortality surgeons, out-of-state referral or avoidance of cardiac surgery/angioplasty for high-risk patients, alteration of contracting choices by insurance companies, and modifications in market share of cardiac hospitals. Evidence related to these impacts is reviewed and critiqued. This communication also includes a summary of numerous studies that used New York's cardiac registries to examine a variety of policy issues regarding the choice and use of cardiac procedures, the comparative effectiveness of competing treatment options, and the examination of the relationship among processes, structures, and outcomes of cardiac care. PMID:22698487

  7. Cardiac conduction system

    Science.gov (United States)

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

  8. Catastrophic debris flows transformed from landslides in volcanic terrains : mobility, hazard assessment and mitigation strategies

    Science.gov (United States)

    Scott, Kevin M.; Macias, Jose Luis; Naranjo, Jose Antonio; Rodriguez, Sergio; McGeehin, John P.

    2001-01-01

    Communities in lowlands near volcanoes are vulnerable to significant volcanic flow hazards in addition to those associated directly with eruptions. The largest such risk is from debris flows beginning as volcanic landslides, with the potential to travel over 100 kilometers. Stratovolcanic edifices commonly are hydrothermal aquifers composed of unstable, altered rock forming steep slopes at high altitudes, and the terrain surrounding them is commonly mantled by readily mobilized, weathered airfall and ashflow deposits. We propose that volcano hazard assessments integrate the potential for unanticipated debris flows with, at active volcanoes, the greater but more predictable potential of magmatically triggered flows. This proposal reinforces the already powerful arguments for minimizing populations in potential flow pathways below both active and selected inactive volcanoes. It also addresses the potential for volcano flank collapse to occur with instability early in a magmatic episode, as well as the 'false-alarm problem'-the difficulty in evacuating the potential paths of these large mobile flows. Debris flows that transform from volcanic landslides, characterized by cohesive (muddy) deposits, create risk comparable to that of their syneruptive counterparts of snow and ice-melt origin, which yield noncohesive (granular) deposits, because: (1) Volcano collapses and the failures of airfall- and ashflow-mantled slopes commonly yield highly mobile debris flows as well as debris avalanches with limited runout potential. Runout potential of debris flows may increase several fold as their volumes enlarge beyond volcanoes through bulking (entrainment) of sediment. Through this mechanism, the runouts of even relatively small collapses at Cascade Range volcanoes, in the range of 0.1 to 0.2 cubic kilometers, can extend to populated lowlands. (2) Collapse is caused by a variety of triggers: tectonic and volcanic earthquakes, gravitational failure, hydrovolcanism, and

  9. Comparison of gated SPECT, echocardiography and cardiac magnetic resonance imaging for the assessment of left ventricular ejection fraction and volumes

    International Nuclear Information System (INIS)

    Left ventricular ejection fraction (LVEF), end-diastolic volume (EDV) and end-systolic volume (ESV) can be determined non-invasively by two-dimensional echocardiography (ECHO), gated single photon emission computed tomography (GSPECT) and cardiac magnetic resonance imaging (CMRI). This study was designed to analyze the concordance between LVEF, EDV and ESV values derived from ECHO, GSPECT and CMRI. ECHO, GSPECT and CMRI were performed in a group of 21 patients with suspected coronary artery disease. LVEF, EDV and ESV values were calculated. The mean LVEF measured with GSPECT, ECHO and CMRI were 5.9+-17.8%, 55.7+-16.4% and 56.4+-15.7% respectively. The mean EDV measured with GSPECT, ECHO and CMRI were 109.2+-42.4 mL, 127.5+-42.2 mL and 91.1+-38.0 mL, respectively. The mean ESV measured with GSPECT, ECHO and CMRI were 54.2+-41.2 mL, 59.9+-37.6 mL, respectively. The results of liner regression analysis showed very good correlation between LVEF and ESV values derived from GSPECT, ECHO and CMRI (r=0.91, r=0.92, r=0.97 for LVEF and r=0.86, r=0.91, r=0.91 for ESV, P<0.091). Good correlation were found between EDV values obtained from GSPECT, ECHO and CMRI (r=0.71, r=0.68, r=0.73, P<0.01). Agreement between these techniques in LVEF values was also good, but not in LV volumes, according to Bland-Altman plots. This study showed good overall correlations between LVEF, EDV and ESV values derived from GSPECT, ECHO and LVEF obtained from any of these three imaging modalities could be used interchangeably. However, care should be taken in comparing LV volumes. (author)

  10. Cardiac morbidity in subjects referred for echocardiographic assessment at a tertiary medical institution in the Nigerian savanna zone.

    Science.gov (United States)

    Sani, M U; Karaye, K M; Ibrahim, D A

    2007-06-01

    Cardiovascular diseases constitute a major public health problem both in the developed and developing countries. The profile of morbidity and mortality however, varies between regions and countries and even within countries. The importance of recognizing the cardiovascular conditions that prevail in a particular area is very important in health planning and for improving healthcare services. We therefore set out to describe the cardiac morbidity pattern from our echocardiographic data. Between August 2002 and September 2004 (24 months), we reviewed the echocardiographic diagnosis of all patients aged 15 years referred for echocardiography. Information obtained from the records included age, gender, names of referring hospital/physician, clinical diagnosis and echocardiogram findings. Data was analyzed using SPSS version 10.0 software. A total of 594 persons were referred for echocardiographic examination in the 2 year study period. Of these, 489 (82.3%) had an abnormal echocardiogram. We analyzed those with abnormal echocardiograms. There were 272 males and 217 females. The male to female ratio was 1.3:1. Hypertensive heart disease was the commonest echocardiographic diagnosis, present in 228 (46.6%) of the patients. This is followed by dilated cardiomyopathy seen in 82 (16.8%) and then rheumatic heart disease in 55 (11.2%). Other findings were Non dilated cardiomyopathy (6.1%), Hypertrophic cardiomyopathy (5.7%), pericardial diseases (3.7%), Ischemic heart disease (4.7%), Cor pulmonale (1.4%) and Endomyocardial fibrosis (0.4%) of patients. It was noted that majority of the cases were advanced with irreversible myocardial damage. Systemic hypertension remains the most important cause of CVD morbidity in savanna region of Nigeria. Addressing the major cardiovascular risk factors especially systemic hypertension will go a long way in reducing the burden of cardiovascular diseases. PMID:19205577

  11. An in vivo assessment of the influence of needle gauges on endodontic irrigation flow rate

    Science.gov (United States)

    Gopikrishna, Velayutham; Sibi, Swamy; Archana, Durvasulu; Pradeep Kumar, Angabakkam Rajasekaran; Narayanan, Lakshmi

    2016-01-01

    Aim: The aim of this clinical study was to assess the influence of irrigation needle gauge on endodontic irrigation flow rates. Settings and Design: In vivo assessment. Materials and Methods: Five specialist endodontists performed intracanal irrigation procedures on 50 mesiobuccal canal of mandibular first molars using three different irrigation needle gauges. Data of time taken for irrigation was recorded by an irrigation testing system and analyzed using independent sample “T” test and one-way analysis of variance (ANOVA) test. The level of significance was set at P < 0.05. Statistical Analysis Used: The following tests were used for the statistical analysis: Independent sample “T” test, one-way ANOVA test, and post hoc multiple comparison was carried out using Tukey's honest significant difference (HSD) test using Statistical Package for the Social Sciences (SPSS) version 16 for Windows. Results: The average flow rate of 26 gauge was 0.27 mLs−1, of 27 gauge was 0.19 mLs−1, and of 30 gauge was 0.09 mls−1. There was statistical significance among the gauges (P < 0.001). 26 gauge had highest flow rate when compared with other groups followed by 27 gauge and 30 gauge respectively. The operator variability for flow rate of three endodontic irrigation needle gauges (26 gauge, 27 gauge, and 30 gauge) was found to be not significant. Conclusions: Needle gauge has significant influence on endodontic irrigation flow rate. PMID:27099430

  12. Reliability-based assessment of flow assurance of hot waxy crude pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Jinjun, Zhang; Wenke, Zhang; Jianlin, Ding; Bo, Yu [China University of Petroleum - Beijing (CUPB), Beijing (China)

    2009-07-01

    Waxy crude is characterized by its high pour point. Pipeline blockage may occur after prolonged shutdown of a pipeline due to crude oil gelation. Another flow assurance problem is the instable operation at a flow rate below the lowest allowable operation flow rate which is dependent on heat transfer of the pipeline and the viscosity vs. temperature relation of the crude pumped. Besides, for pipelines with thick wax deposition layer, massive depletion of wax deposit in some cases such as pipeline restart at high expelling pressure may also result in blockage of the pipeline, and the pig may be jammed during pigging as a result of thick wax deposition. Conventionally, assessment of these risks has been made by using the deterministic approach. However, many related physical quantities are subject to uncertainty and contribute to reliability of flow assurance. Therefore, the probabilistic approach is suggested and a framework of reliability based assessment of flow assurance of waxy crude pipelines is proposed in this paper. Discussions are also made on the limit state functions and target safety level. In the future study, development of an efficient and robust stochastic-numerical method is crucial. (author)

  13. Assessment of horizontal in-tube condensation models using MARS code. Part I: Stratified flow condensation

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Seong-Su [Department of Engineering Project, FNC Technology Co., Ltd., Bldg. 135-308, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Department of Nuclear Engineering, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Hong, Soon-Joon, E-mail: sjhong90@fnctech.com [Department of Engineering Project, FNC Technology Co., Ltd., Bldg. 135-308, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Park, Ju-Yeop; Seul, Kwang-Won [Korea Institute of Nuclear Safety, 19 Kuseong-dong, Yuseong-gu, Daejon (Korea, Republic of); Park, Goon-Cherl [Department of Nuclear Engineering, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer This study collected 11 horizontal in-tube condensation models for stratified flow. Black-Right-Pointing-Pointer This study assessed the predictive capability of the models for steam condensation. Black-Right-Pointing-Pointer Purdue-PCCS experiments were simulated using MARS code incorporated with models. Black-Right-Pointing-Pointer Cavallini et al. (2006) model predicts well the data for stratified flow condition. Black-Right-Pointing-Pointer Results of this study can be used to improve condensation model in RELAP5 or MARS. - Abstract: The accurate prediction of the horizontal in-tube condensation heat transfer is a primary concern in the optimum design and safety analysis of horizontal heat exchangers of passive safety systems such as the passive containment cooling system (PCCS), the emergency condenser system (ECS) and the passive auxiliary feed-water system (PAFS). It is essential to analyze and assess the predictive capability of the previous horizontal in-tube condensation models for each flow regime using various experimental data. This study assessed totally 11 condensation models for the stratified flow, one of the main flow regime encountered in the horizontal condenser, with the heat transfer data from the Purdue-PCCS experiment using the multi-dimensional analysis of reactor safety (MARS) code. From the assessments, it was found that the models by Akers and Rosson, Chato, Tandon et al., Sweeney and Chato, and Cavallini et al. (2002) under-predicted the data in the main condensation heat transfer region, on the contrary to this, the models by Rosson and Meyers, Jaster and Kosky, Fujii, Dobson and Chato, and Thome et al. similarly- or over-predicted the data, and especially, Cavallini et al. (2006) model shows good predictive capability for all test conditions. The results of this study can be used importantly to improve the condensation models in thermal hydraulic code, such as RELAP5 or MARS code.

  14. Assessment of horizontal in-tube condensation models using MARS code. Part I: Stratified flow condensation

    International Nuclear Information System (INIS)

    Highlights: ► This study collected 11 horizontal in-tube condensation models for stratified flow. ► This study assessed the predictive capability of the models for steam condensation. ► Purdue-PCCS experiments were simulated using MARS code incorporated with models. ► Cavallini et al. (2006) model predicts well the data for stratified flow condition. ► Results of this study can be used to improve condensation model in RELAP5 or MARS. - Abstract: The accurate prediction of the horizontal in-tube condensation heat transfer is a primary concern in the optimum design and safety analysis of horizontal heat exchangers of passive safety systems such as the passive containment cooling system (PCCS), the emergency condenser system (ECS) and the passive auxiliary feed-water system (PAFS). It is essential to analyze and assess the predictive capability of the previous horizontal in-tube condensation models for each flow regime using various experimental data. This study assessed totally 11 condensation models for the stratified flow, one of the main flow regime encountered in the horizontal condenser, with the heat transfer data from the Purdue-PCCS experiment using the multi-dimensional analysis of reactor safety (MARS) code. From the assessments, it was found that the models by Akers and Rosson, Chato, Tandon et al., Sweeney and Chato, and Cavallini et al. (2002) under-predicted the data in the main condensation heat transfer region, on the contrary to this, the models by Rosson and Meyers, Jaster and Kosky, Fujii, Dobson and Chato, and Thome et al. similarly- or over-predicted the data, and especially, Cavallini et al. (2006) model shows good predictive capability for all test conditions. The results of this study can be used importantly to improve the condensation models in thermal hydraulic code, such as RELAP5 or MARS code.

  15. Developing New Modelling Tools for Environmental Flow Assessment in Regulated Salmon Rivers

    Science.gov (United States)

    Geris, Josie; Soulsby, Chris; Tetzlaff, Doerthe

    2013-04-01

    of the natural flow variability and the hydrological impacts of the regulation is unavailable, partly because pre-regulation data of existing hydropower schemes are lacking. Here we develop a novel modelling approach for characterising natural flow regimes and defining hydrological flow indices. This allows us to quantitatively assess the impacts of hydropower to better inform environmental flow requirements for the Atlantic salmon river ecosystem. Results are presented for the River Lyon (390 km2), a regulated headwater catchment of the River Tay. The HBV hydrological rainfall-runoff model is used to simulate flows, based on calibrated parameters from regulated flow data, with the current hydropower scheme active. For this, the HBV model is adapted to be able to incorporate water transfers and regulated flows. The natural hydrological indices are derived from the simulated pre-regulation data, and compared with those of the regulated data to investigate the impact of the regulation on these at different critical times for Atlantic salmon. The sensitivity of the system to change is also investigated to explore the extent to which flow variables can be modified without major degradation to the river's ecosystem, while still maintaining viable hydropower generation. The modelling approach presented will provide the basis for assessing impacts on hydrological flow indices and informing environmental flows in regions with similar heavily regulated mountain river ecosystems.

  16. A portable cadmium telluride multidetector probe for cardiac function monitoring

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-06-01

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

  17. A portable cadmium telluride multidetector probe for cardiac function monitoring

    International Nuclear Information System (INIS)

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

  18. A biological tool to assess flow connectivity in reference temporary streams from the Mediterranean Basin.

    Science.gov (United States)

    Cid, N; Verkaik, I; García-Roger, E M; Rieradevall, M; Bonada, N; Sánchez-Montoya, M M; Gómez, R; Suárez, M L; Vidal-Abarca, M R; Demartini, D; Buffagni, A; Erba, S; Karaouzas, I; Skoulikidis, N; Prat, N

    2016-01-01

    Many streams in the Mediterranean Basin have temporary flow regimes. While timing for seasonal drought is predictable, they undergo strong inter-annual variability in flow intensity. This high hydrological variability and associated ecological responses challenge the ecological status assessment of temporary streams, particularly when setting reference conditions. This study examined the effects of flow connectivity in aquatic macroinvertebrates from seven reference temporary streams across the Mediterranean Basin where hydrological variability and flow conditions are well studied. We tested for the effect of flow cessation on two streamflow indices and on community composition, and, by performing random forest and classification tree analyses we identified important biological predictors for classifying the aquatic state either as flowing or disconnected pools. Flow cessation was critical for one of the streamflow indices studied and for community composition. Macroinvertebrate families found to be important for classifying the aquatic state were Hydrophilidae, Simuliidae, Hydropsychidae, Planorbiidae, Heptageniidae and Gerridae. For biological traits, trait categories associated to feeding habits, food, locomotion and substrate relation were the most important and provided more accurate predictions compared to taxonomy. A combination of selected metrics and associated thresholds based on the most important biological predictors (i.e. Bio-AS Tool) were proposed in order to assess the aquatic state in reference temporary streams, especially in the absence of hydrological data. Although further development is needed, the tool can be of particular interest for monitoring, restoration, and conservation purposes, representing an important step towards an adequate management of temporary rivers not only in the Mediterranean Basin but also in other regions vulnerable to the effects of climate change. PMID:26209067

  19. Automated Segmentation of Cardiac Magnetic Resonance Images

    DEFF Research Database (Denmark)

    Stegmann, Mikkel Bille; Nilsson, Jens Chr.; Grønning, Bjørn A.

    2001-01-01

    Magnetic resonance imaging (MRI) has been shown to be an accurate and precise technique to assess cardiac volumes and function in a non-invasive manner and is generally considered to be the current gold-standard for cardiac imaging [1]. Measurement of ventricular volumes, muscle mass and function...

  20. Cardiac Vagal Regulation and Early Peer Status

    Science.gov (United States)

    Graziano, Paulo A.; Keane, Susan P.; Calkins, Susan D.

    2007-01-01

    A sample of 341 5 1/2-year-old children participating in an ongoing longitudinal study was the focus of a study on the relation between cardiac vagal regulation and peer status. To assess cardiac vagal regulation, resting measures of respiratory sinus arrhythmia (RSA) and RSA change (suppression) to 3 cognitively and emotionally challenging tasks…

  1. Assessment of glomerular filtration rate and effective renal plasma flow in cystic fibrosis

    International Nuclear Information System (INIS)

    A study was conducted to examine renal function in 10 healthy control subjects and eight patients with cystic fibrosis in stable condition. Sequential bolus injections of /sup 99m/Tc-DTPA and 125I-OIH were administered to assess glomerular filtration rate and effective renal plasma flow, respectively. Blood was subsequently collected for 3 hours, and urine for 24 hours. Renal clearances of both radioisotope markers were virtually identical in patients and controls. Inasmuch as neither glomerular filtration rate nor effective renal plasma flow was enhanced in patients with cystic fibrosis, increased clearance of drugs in these patients is unlikely to be the result of enhanced glomerular filtration or tubular secretion

  2. A novel, microscope based, non invasive Laser Doppler flowmeter for choroidal blood flow assessment

    OpenAIRE

    Strohmaier, C; Werkmeister, RM; Bogner, B; Runge, C; Schroedl, F; Brandtner, H; Radner, W; Schmetterer, L; Kiel, JW; Grabnerand, G; Reitsamer, HA

    2011-01-01

    Impaired ocular blood flow is involved in the pathogenesis of numerous ocular diseases like glaucoma or AMD. The purpose of the present study was to introduce and validate a novel, microscope based, non invasive laser Doppler flowmeter (NILDF) for measurement of blood flow in the choroid. The custom made NI-LDF was compared with a commercial fiber optic based laser Doppler flowmeter (Perimed PF4000). Linearity and stability of the NI-LDF were assessed in a silastic tubing model (i.d. 0.3 mm) ...

  3. PERFORMANCE ASSESSMENT OF MAJOR U.S. AIRLINES VIA CASH FLOW RATIOS

    OpenAIRE

    Stepanyan Armen

    2013-01-01

    The paper addresses the assessment of major U.S. airlinesâ€(tm) liquidity and solvency based on information disclosed in the statements of cash flows as part of their 10-K Form annual reports filed with the Securities and Exchange Commission. Conducting financial statement analysis for major U.S. airlines has generated deep interest in and a significant importance towards using various frequently used cash flow ratios to gauge U.S. airlinesâ€(tm) viability both in the short term and long term...

  4. Cardiac imaging. A multimodality approach

    International Nuclear Information System (INIS)

    An excellent atlas on modern diagnostic imaging of the heart Written by an interdisciplinary team of experts, Cardiac Imaging: A Multimodality Approach features an in-depth introduction to all current imaging modalities for the diagnostic assessment of the heart as well as a clinical overview of cardiac diseases and main indications for cardiac imaging. With a particular emphasis on CT and MRI, the first part of the atlas also covers conventional radiography, echocardiography, angiography and nuclear medicine imaging. Leading specialists demonstrate the latest advances in the field, and compare the strengths and weaknesses of each modality. The book's second part features clinical chapters on heart defects, endocarditis, coronary heart disease, cardiomyopathies, myocarditis, cardiac tumors, pericardial diseases, pulmonary vascular diseases, and diseases of the thoracic aorta. The authors address anatomy, pathophysiology, and clinical features, and evaluate the various diagnostic options. Key features: - Highly regarded experts in cardiology and radiology off er image-based teaching of the latest techniques - Readers learn how to decide which modality to use for which indication - Visually highlighted tables and essential points allow for easy navigation through the text - More than 600 outstanding images show up-to-date technology and current imaging protocols Cardiac Imaging: A Multimodality Approach is a must-have desk reference for cardiologists and radiologists in practice, as well as a study guide for residents in both fields. It will also appeal to cardiac surgeons, general practitioners, and medical physicists with a special interest in imaging of the heart. (orig.)

  5. Relationship of flow cytometric sperm integrity assessments with boar fertility performance under optimized field conditions.

    Science.gov (United States)

    Broekhuijse, M L W J; Šoštarić, E; Feitsma, H; Gadella, B M

    2012-12-01

    The number of intact and functional spermatozoa in semen can be assessed with flow cytometry and is believed to relate to male fertility. The aim of this study was to examine whether currently used sperm integrity assessments with flow cytometry correlate with field fertility data obtained for boar semen. For this purpose, 20 boars were followed for a 20-wk period (with a total average production of 33 ejaculates per boar) and the obtained fertility results (farrowing rate and number of piglets born) of commercial artificial insemination doses made from these ejaculates were recorded. Fertility results were corrected for farm, sow, boar, and semen-related parameters. From the same semen samples, sperm cell integrity was assessed with respect to DNA and to membrane integrity, acrosome intactness and responsiveness, and mitochondrial potential using established flow cytometric assays. This was done on freshly produced semen and on semen stored for up to 15 d. Remarkably, none of the individual membrane integrity variables was significantly related to fertility results. In contrast, the amount of DNA damage as assessed at 7 to 10 d and at 14 to 15 d of semen storage related to farrowing rate (P = 0.0400) and total number of piglets born (P = 0.0310), respectively. Therefore, the degree of DNA damage in stored boar semen samples may be a useful factor to evaluate semen as an indicator for litter size and farrowing rate. PMID:23255815

  6. Direct and indirect assessment of skeletal muscle blood flow in chronic congestive heart failure

    Energy Technology Data Exchange (ETDEWEB)

    LeJemtel, T.H.; Scortichini, D.; Katz, S.

    1988-09-09

    In patients with chronic congestive heart failure (CHF), skeletal muscle blood flow can be measured directly by the continuous thermodilution technique and by the xenon-133 clearance method. The continuous thermodilution technique requires retrograde catheterization of the femoral vein and, thus, cannot be repeated conveniently in patients during evaluation of pharmacologic interventions. The xenon-133 clearance, which requires only an intramuscular injection, allows repeated determination of skeletal muscle blood flow. In patients with severe CHF, a fixed capacity of the skeletal muscle vasculature to dilate appears to limit maximal exercise performance. Moreover, the changes in peak skeletal muscle blood flow noted during long-term administration of captopril, an angiotensin-converting enzyme inhibitor, appears to correlate with the changes in aerobic capacity. In patients with CHF, resting supine deep femoral vein oxygen content can be used as an indirect measurement of resting skeletal muscle blood flow. The absence of a steady state complicates the determination of peak skeletal muscle blood flow reached during graded bicycle or treadmill exercise in patients with chronic CHF. Indirect assessments of skeletal muscle blood flow and metabolism during exercise performed at submaximal work loads are currently developed in patients with chronic CHF.

  7. Myocardial scintigraphy with 201Tl and quantitative assessment of myocardial blood flow

    International Nuclear Information System (INIS)

    A newly introduced radionuclide for myocardial imaging, 201-Tl, was studied. Twenty-two subjects consisting of 7 normals, 12 with ischemic heart disease and 3 with hypertrophic cardiomyopathy (HCM) were selected. On intravenous administration of 201-Tl(1.5 - 20. mCi), initial transit of the tracer through the heart, as well as subsequent uptake by the myocardium, were recorded by a scintillation camera. The later process showed the distribution of the myocardial blood flow (MBF). A normal myocardial scintigraphy revealed the left-sided myocardial mass predominantly, whereas the right side or the septum predominated in the case of tetralogy of fallot (T/F) or idiopathic hypertrophic subuaortic stenosis (IHSS). An ischemic or infarcted area of the myocardium in ischemic heart disease (IHD) was compatible with electrocardiographic findings, and revealed defects even in an equivocal case on ECG. Since the ratio of radioactivity taken up by the myocardium (U) to the total injected dosis (I) is assumed to be proportional to the fractional MBF of cardiac output (CO), MBF/CO is calculated by ratio of the radioactivity selected from myocardial region on the later recording to that from the entire region on the initial transit of the tracer bolus. The average MBF/CO of normals was 4.4 +- 0.5%, IHD 4.0 +- 0.8% and HCM 5.5 +- 1.2%. On exercise loading, a significant increase of this value was observed in normals, whereas no change was observed in IHD. (auth.)

  8. Assessment of right ventricular oxidative metabolism by PET in patients with idiopathic dilated cardiomyopathy undergoing cardiac resynchronisation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Knuuti, Juhani; Naum, Alexandru; Stolen, Kira Q.; Kalliokoski, Riikka [University of Turku, Turku PET Centre, P.O. Box 52, Turku (Finland); Sundell, Jan [University of Turku, Turku PET Centre, P.O. Box 52, Turku (Finland); University of Turku, Department of Medicine, Turku (Finland); Engblom, Erik; Koistinen, Juhani; Airaksinen, K.E. Juhani [University of Turku, Department of Medicine, Turku (Finland); Ylitalo, Antti [Satakunta Central Hospital, Department of Medicine, Pori (Finland); Nekolla, Stephan G. [Klinikum rechts der Isar der Technischen Universitaet Muenchen, Klinik und Poliklinik fuer Nuklearmedizin, Munich (Germany); Bax, K.E. Jeroen J. [Leiden University, Department of Cardiology, Leiden (Netherlands)

    2004-12-01

    Right ventricular (RV) performance is known to have prognostic value in patients with congestive heart failure (CHF). Cardiac resynchronisation therapy (CRT) has been found to enhance left ventricular (LV) energetics and metabolic reserve in patients with heart failure. The interplay between the LV and RV may play an important role in CRT response. The purpose of the study was to investigate RV oxidative metabolism, metabolic reserve and the effects of CRT in patients with CHF and left bundle brach block. In addition, the role of the RV in the response to CRT was evaluated. Ten patients with idiopathic dilated cardiomyopathy who had undergone implantation of a biventricular pacemaker 8{+-}5 months earlier were studied under two conditions: CRT ON and after CRT had been switched OFF for 24 h. Oxidative metabolism was measured using [{sup 11}C]acetate positron emission tomography (K{sub mono}). The measurements were performed at rest and during dobutamine-induced stress (5 {mu}g/kg per minute). LV performance and interventricular mechanical delay (interventricular asynchrony) were measured using echocardiography. CRT had no effect on RV K{sub mono} at rest (ON: 0.052{+-}0.014, OFF: 0.047{+-}0.018, NS). Dobutamine-induced stress increased RV K{sub mono} significantly under both conditions but oxidative metabolism was more enhanced when CRT was ON (0.076{+-}0.026 vs 0.065{+-}0.027, p=0.003). CRT shortened interventricular delay significantly (45{+-}33 vs 19{+-}35 ms, p=0.05). In five patients the response to CRT was striking (32% increase in mean LV stroke volume, range 18-36%), while in the other five patients no response was observed (mean change +2%, range -6% to +4%). RV K{sub mono} and LV stroke volume response to CRT correlated inversely (r=-0.66, p=0.034). None of the other measured parameters, including all LV parameters and electromechanical parameters, were associated with the response to CRT. In responders, RV K{sub mono} with CRT OFF was significantly lower

  9. Assessment of fluid flow characteristics for fluidic device in APR 1400

    International Nuclear Information System (INIS)

    New evolutionary light water reactors (LWRs) are being developed all over the world today. Some of those LWRs employ so-called passive safety components that use natural phenomena as the driving force such as expansion of pressurised gas, natural circulation, and so forth. These passive safety components and their systems are applied to improve the safety of nuclear power plants, further achieving not only to simplify the safety system, but also to improve its reliability and to provide a sufficient time margin to enable the operators to cope with accidents. The APR 1400 (Advanced Pressurised Water Reactor), which is a Korean Next Generation Reactor, adopted fluidic device as one of its passive pieces of safety equipment. The fluidic device is installed at the bottom of the inner space of the Safety Injection Tank (SIT) to control the flow rate of emergency cooling water during a large break loss of coolant accident (LBLOCA). During the past two years, a scale model test to obtain the required flow characteristics of the device under the APR 1400 specific conditions has been performed in Korea. The performance verification test was conducted to obtain the optimum characteristics and design data of full fluidic device (FD). In this study, the thermal-hydraulic characteristics for the fluidic device are analysed using SIMPLE algorithm with an aim to develop the assessment and verification guidelines for the APR 1400. To assess the flow characteristics for fluidic device, a three dimensional numerical model is developed and its results are compared with those of experiments. The fluid flow characteristics of the FD, which is passive flow control device in the SIT of APR-1400 are assessed using SIMPLE algorithm using FLUENT code and are compared with the experimental results. In this study, the fluid flow rate and pressure in the FD are predicted on the basis of the boundary condition at the entrance of supply port, control port, and discharge port respectively, so as

  10. Mechanical Regulation of Cardiac Development

    Directory of Open Access Journals (Sweden)

    HuseyinCagatayYalcin

    2014-08-01

    Full Text Available Mechanical forces are an essential contributor to and unavoidable component of cardiac formation, both inducing and orchestrating local and global molecular and cellular changes. Experimental animal studies have contributed substantially to understanding the mechanobiology of heart development. More recent integration of high-resolution imaging modalities with computational modeling has greatly improved our quantitative understanding of hemodynamic flow in heart development. Merging these latest experimental technologies with molecular and genetic signaling analysis will accelerate our understanding of the relationships integrating mechanical and biological signaling for proper cardiac formation. These advances will likely be essential for clinically translatable guidance for targeted interventions to rescue malforming hearts and/or reconfigure malformed circulations for optimal performance. This review summarizes our current understanding on the levels of mechanical signaling in the heart and their roles in orchestrating cardiac development.

  11. Were the May 2012 Emilia-Romagna earthquakes induced? A coupled flow-geomechanics modeling assessment

    Science.gov (United States)

    Juanes, R.; Jha, B.; Hager, B. H.; Shaw, J. H.; Plesch, A.; Astiz, L.; Dieterich, J. H.; Frohlich, C.

    2016-07-01

    Seismicity induced by fluid injection and withdrawal has emerged as a central element of the scientific discussion around subsurface technologies that tap into water and energy resources. Here we present the application of coupled flow-geomechanics simulation technology to the post mortem analysis of a sequence of damaging earthquakes (Mw = 6.0 and 5.8) in May 2012 near the Cavone oil field, in northern Italy. This sequence raised the question of whether these earthquakes might have been triggered by activities due to oil and gas production. Our analysis strongly suggests that the combined effects of fluid production and injection from the Cavone field were not a driver for the observed seismicity. More generally, our study illustrates that computational modeling of coupled flow and geomechanics permits the integration of geologic, seismotectonic, well log, fluid pressure and flow rate, and geodetic data and provides a promising approach for assessing and managing hazards associated with induced seismicity.

  12. Quantification in non-invasive cardiac imaging: CT and MR

    NARCIS (Netherlands)

    A. Rossi (Alexia)

    2013-01-01

    markdownabstract__Abstract__ The diagnosis and management of cardiac disease require a precise assessment of morphological and functional cardiac parameters. This thesis is divided in three parts. Part I emphasizes the role of cardiac computed tomography (CT) in the diagnosis of patients with ische

  13. Hazards Assessment of Regional Debris Flows Based on Geographic Information Science

    Institute of Scientific and Technical Information of China (English)

    JIANG Xiaobo; GUI Peng

    2007-01-01

    Supported by the spatial analysis feature of geographic information science and assessment model of regional debris flows, hazards degrees of the debris flows in the Upper Yangtze River Watershed (UYRW) are divided into five grades based on grid cell. The area of no danger, light danger, medium danger, severe danger and extreme severe danger regions respectively are 278 000, 288 000, 217 000, 127 000, 15 000 km2. Furthermore, the counties in the UYRW are classified into four classes based on the hazards degrees in each county. The number of severe danger, medium danger, light danger and no danger counties respectively are 49, 82, 77 and 105. The assessment results will be provided for the hazards forecasting and mitigation in the UYRW and ongoing regionalization of Main Function Regions in China as data and technique framework.

  14. Debris-flow hazard assessment at regional scale by combining susceptibility mapping and radar rainfall

    Directory of Open Access Journals (Sweden)

    M. Berenguer

    2014-10-01

    Full Text Available This work presents a technique for debris flow (DF hazard assessment able to be used in the framework of DF early warning systems at regional scale. The developed system is applied at subbasin scale and is based on the concepts of fuzzy logic to combine two ingredients: (i DF subbasin susceptibility assessment based on geomorphological variables, and (ii the magnitude of the rainfall situation as depicted from radar rainfall estimates. The output of the developed technique is a three-class hazard level ("low", "moderate" and "high" in each subbasin when a new radar rainfall map is available. The developed technique has been applied in a domain in the Eastern Pyrenees (Spain from May to October 2010. The estimated hazard level stayed "low" during the entire period in 20% of the subbasins, while, in the most susceptible subbasins, the hazard level was at least moderate for up to10 days. Quantitative evaluation of the estimated hazard level was possible in a subbasin where debris flows were monitored during the analysis period. The technique was able to identify the 3 events observed in the catchment (1 debris flow and 2 hyperconcentrated flow events and produced no false alarm.

  15. A simple microfluidic device for the deformability assessment of blood cells in a continuous flow.

    Science.gov (United States)

    Rodrigues, Raquel O; Pinho, Diana; Faustino, Vera; Lima, Rui

    2015-12-01

    Blood flow presents several interesting phenomena in microcirculation that can be used to develop microfluidic devices capable to promote blood cells separation and analysis in continuous flow. In the last decade there have been numerous microfluidic studies focused on the deformation of red blood cells (RBCs) flowing through geometries mimicking microvessels. In contrast, studies focusing on the deformation of white blood cells (WBCs) are scarce despite this phenomenon often happens in the microcirculation. In this work, we present a novel integrative microfluidic device able to perform continuous separation of a desired amount of blood cells, without clogging or jamming, and at the same time, capable to assess the deformation index (DI) of both WBCs and RBCs. To determine the DI of both WBCs and RBCs, a hyperbolic converging microchannel was used, as well as a suitable image analysis technique to measure the DIs of these blood cells along the regions of interest. The results show that the WBCs have a much lower deformability than RBCs when subjected to the same in vitro flow conditions, which is directly related to their cytoskeleton and nucleus contents. The proposed strategy can be easily transformed into a simple and inexpensive diagnostic microfluidic system to simultaneously separate and assess blood cells deformability. PMID:26482154

  16. Energy flow analysis and assessment of energy saving potentials in a research and development plant

    International Nuclear Information System (INIS)

    This thesis is concerned with an energy flow analysis in order to assess the situation of the energy demand in the research and development plant AVC in Austria. The possibilities of more effective using the energy resources are investigated. The economics of the distribution of the electrical current and estimates of the energy demand are examined comparison with other firms are made. The consequences of better scopes of negotiations are worked out. (Suda)

  17. Cardiac MRI in Athletes

    NARCIS (Netherlands)

    Luijkx, T.

    2012-01-01

    Cardiac magnetic resonance imaging (CMR) is often used in athletes to image cardiac anatomy and function and is increasingly requested in the context of screening for pathology that can cause sudden cardiac death (SCD). In this thesis, patterns of cardiac adaptation to sports are investigated with C

  18. Flow

    DEFF Research Database (Denmark)

    2009-01-01

    Flow er en positiv, koncentreret tilstand, hvor al opmærksomhed er samlet om en bestemt aktivitet, som er så krævende og engagerende, at man må anvende mange mentale ressourcer for at klare den. Tidsfornemmelsen forsvinder, og man glemmer sig selv. 'Flow' er den første af en række udsendelser om...

  19. Assessment of CSF dynamics and venous flow in the superior sagittal sinus by MRI in idiopathic intracranial hypertension: a preliminary study

    DEFF Research Database (Denmark)

    Gideon, P; Sørensen, P S; Thomsen, C;

    1994-01-01

    ). We examined 12 patients with idiopathic intracranial hypertension (IIH; pseudotumour cerebri), and 10 healthy volunteers. The peak caudal and rostral CSF flow in the aqueduct during the cardiac cycle did not differ significantly between the patients and the volunteers. A significant correlation...

  20. A Refined Multiscale Self-Entropy Approach for the Assessment of Cardiac Control Complexity: Application to Long QT Syndrome Type 1 Patients

    Directory of Open Access Journals (Sweden)

    Vlasta Bari

    2015-11-01

    Full Text Available The study proposes the contemporaneous assessment of conditional entropy (CE and self-entropy (sE, being the two terms of the Shannon entropy (ShE decomposition, as a function of the time scale via refined multiscale CE (RMSCE and sE (RMSsE with the aim at gaining insight into cardiac control in long QT syndrome type 1 (LQT1 patients featuring the KCNQ1-A341V mutation. CE was estimated via the corrected CE (CCE and sE as the difference between the ShE and CCE. RMSCE and RMSsE were computed over the beat-to-beat series of heart period (HP and QT interval derived from 24-hour Holter electrocardiographic recordings during daytime (DAY and nighttime (NIGHT. LQT1 patients were subdivided into asymptomatic and symptomatic mutation carriers (AMCs and SMCs according to the severity of symptoms and contrasted with non-mutation carriers (NMCs. We found that RMSCE and RMSsE carry non-redundant information, separate experimental conditions (i.e., DAY and NIGHT within a given group and distinguish groups (i.e., NMC, AMC and SMC assigned the experimental condition. Findings stress the importance of the joint evaluation of RMSCE and RMSsE over HP and QT variabilities to typify the state of the autonomic function and contribute to clarify differences between AMCs and SMCs.

  1. Manual correction of semi-automatic three-dimensional echocardiography is needed for right ventricular assessment in adults; validation with cardiac magnetic resonance

    Directory of Open Access Journals (Sweden)

    Ostenfeld Ellen

    2012-01-01

    Full Text Available Abstract Background Three-dimensional echocardiography (3DE and semi-automatic right ventricular delineation has been proposed as an appropriate method for right ventricle (RV evaluation. We aimed to examine how manual correction of semi-automatic delineation influences the accuracy of 3DE for RV volumes and function in a clinical adult setting using cardiac magnetic resonance (CMR as the reference method. We also examined the feasibility of RV visualization with 3DE. Methods 62 non-selected patients were examined with 3DE (Sonos 7500 and iE33 and with CMR (1.5T. Endocardial RV contours of 3DE-images were semi-automatically assessed and manually corrected in all patients. End-diastolic (EDV, end-systolic (ESV volumes, stroke volume (SV and ejection fraction (EF were computed. Results 53 patients (85% had 3DE-images feasible for examination. Correlation coefficients and Bland Altman biases between 3DE with manual correction and CMR were r = 0.78, -22 ± 27 mL for EDV, r = 0.83, -7 ± 16 mL for ESV, r = 0.60, -12 ± 18 mL for SV and r = 0.60, -2 ± 8% for EF (p Conclusion Manual correction of the 3DE semi-automatic RV delineation decreases the bias and is needed for acceptable clinical accuracy. 3DE is highly feasible for visualizing the RV in an adult clinical setting.

  2. Cardiac Anxiety in people with and without Coronary Atherosclerosis

    OpenAIRE

    Marker, Craig D.; Carmin, Cheryl N.; Ownby, Raymond L.

    2008-01-01

    Many studies have shown that cardiac anxiety when occurring in the absence of coronary artery disease is common and quite costly. The Cardiac Anxiety Questionnaire (CAQ) is an 18 item self-report measure that assesses anxiety related to cardiac symptoms. In order to better understand the construct of cardiac anxiety, a factor analysis was conducted on CAQ data from 658 individuals who were self- or physician- referred for electron beam tomographic screening to determine whether clinically sig...

  3. Methodology for collision risk assessment of an airspace flow corridor concept

    International Nuclear Information System (INIS)

    This paper presents a methodology to estimate the collision risk associated with a future air-transportation concept called the flow corridor. This concept is designed to reduce congestion and increase throughput in en-route airspace by creating dedicated flight corridors across the continent. The methodology is a hybrid collision-risk methodology combining Monte Carlo simulation and dynamic event trees. Monte Carlo simulation is used to model the movement of aircraft within the corridor and to identify potential trajectories that might lead to a collision. Dynamic event trees are used to evaluate the effectiveness of subsequent safety layers that protect against collisions. The overall risk assessment captures the unique characteristics of the flow corridor concept, including self-separation within the corridor, lane change maneuvers, speed adjustments, and the automated separation assurance system. A tradeoff between safety and throughput is conducted, and a sensitivity analysis identifies the most critical parameters in the model. - Highlights: • A methodology is developed to estimate the collision risk of flow corridor concept. • Unique characteristics of the flow corridor concept are included. • The flow corridor concept can meet an international target level of safety. • Throughput can be increased by reducing separation to 2 nautical miles

  4. An updated fracture-flow model for total-system performance assessment of Yucca Mountain

    International Nuclear Information System (INIS)

    Improvements have been made to the fracture-flow model being used in the total-system performance assessment of a potential high-level radioactive waste repository at Yucca Mountain, Nevada. The ''weeps model'' now includes (1) weeps of varied sizes, (2) flow-pattern fluctuations caused by climate change, and (3) flow-pattern perturbations caused by repository heat generation. Comparison with the original weeps model indicates that allowing weeps of varied sizes substantially reduces the number of weeps and the number of containers contacted by weeps. However, flow-pattern perturbations caused by either climate change or repository heat generation greatly increases the number of containers contacted by weeps. In preliminary total-system calculations, using a phenomenological container-failure and radionuclide-release model, the weeps model predicts that radionuclide releases from a high-level radioactive waste repository at Yucca Mountain will be below the EPA standard specified in 40 CFR 191, but that the maximum radiation dose to an individual could be significant. Specific data from the site are required to determine the validity of the weep-flow mechanism and to better determine the parameters to which the dose calculation is sensitive

  5. Flow cytometry for the assessment of animal sperm integrity and functionality: state of the art

    Institute of Scientific and Technical Information of China (English)

    Md.Sharoare Hossain; Anders Johannisson; Margareta Wallgren; Szabolcs Nagy; Amanda Pimenta Siqueira; Heriberto Rodriguez-Martinez

    2011-01-01

    Flow cytometry is now a recognized methodology within animal spermatology, and has moved from being a research tool to become routine in the assessment of animal semen destined to breeding. The availability of 'bench-top' flow cytometers and of newer and versatile markers for cell structure and function had allowed the instrumentation to measure more sperm parameters, from viability to reactiveness when exposed to exogenous stimuli, and to increase our capabilities to sort spermatozoa for potential fertilizing capacity, or chromosomal sex. The present review summarizes the state of the art regarding flow cytometry applied to animal andrology, albeit keeping an open comparative intent. It critically evaluates the present and future capabilities of flow cytometry for the diagnostics of potential fertility and for the development of current reproductive technologies such as sperm freezing, sperm selection and sperm sorting. The flow cytometry methods will probably further revolutionize our understanding of the sperm physiology and their functionality, and will undoubtedly extend its application in isolating many uncharacterized features of spermatozoa. However, continuous follow-up of the methods is a necessity owing to technical developments and the complexity of mapping spermatozoa.

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

    International Nuclear Information System (INIS)

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

  7. Assessment of TRAC-PF1/MOD1 for countercurrent - annular and stratified flows

    International Nuclear Information System (INIS)

    I performed an independent assessment of the Transient Reactor Analysis Code, TRAC-PF1/MOD1, using air-water countercurrent-flow limitation data in circular pipes for annular, annular-mist, and stratified flows. Tubes were configurated in the vertical direction with different lengths and diameters and at angles of 60 deg, 40 deg, 20 deg, and 0 deg from the horizontal, respectively. Also, comparisons were made with data from a horizontal tube with an inclined riser at the end that simulated a pressurized water reactor (PWR) hot leg. TRAC-PF1/MOD1 was modified to study the effects of using two different correlations for interfacial shear in the annular-mist flow regime: the Wallis and Bharathan correlations. TRAC-PF1/MOD1 with the Wallis correlation predicts the point of no water penetration (bypass point) in the annular-mist flow regime except for the 40 deg inclined tube. However, for the region of partial water penetration, use of the Bharathan correlation in TRAC-PF1/MOD1 gives better agreement with data. Additional form losses were required at both ends of the tube to predict the flow rate of falling water accurately for the vertical tube. In the stratified-flow regime, TRAC-PF1/MOD1 underpredicts the air velocity which gives the bypass point but gives good agreement for the region of partial penetration. For the case of a simulated PWR hot leg, the code yields similar results to those obtained for the stratified-flow regime. (author)

  8. Evaluation of a 4-channel phased-array coil for MR cardiac imaging. Quantitative assessment of signal to noise ratio improvement

    International Nuclear Information System (INIS)

    Recently, the utility of cardiac MR imaging has been increasing for morphological and functional analysis of the heart. However, since the image acquisition time is substantially shortened with recent fast cardiac MR sequences, it is often difficult to obtain a good signal to noise ratio (SNR) in fast cardiac MR imaging. The purpose of the current study was to optimize the design of a 4-channel multi-coil array for cardiac MR imaging, and to compare the performance of this new coil array with that of other product coils by evaluation of the SNR in a phantom and in healthy volunteers. In the phantom study using SE and FGR sequences, the cardiac coils provided significantly better SNR values than those for the other coils, not only in the peripheral part but also in the center of the phantom (p<0.01). When the SNR values were calculated for the anterior, septal, posteroinferior and lateral walls of the volunteer hearts, the SNR values obtained using the cardiac coil were significantly better than those with any of the other coils evaluated in all 4 myocardial segments (p<0.01). These results suggest that the new 4-channel cardiac multi-coil array is useful for MR imaging of the heart. (author)

  9. Influence of pre-infarction angina, collateral flow, and pre-procedural TIMI flow on myocardial salvage index by cardiac magnetic resonance in patients with ST-segment elevation myocardial infarction

    DEFF Research Database (Denmark)

    Lønborg, Jacob Thomsen; Kelbæk, Henning Skov; Vejlstrup, Niels Grove;

    2012-01-01

    salvage index (MSI) and infarct size adjusting for area at risk in patients with STEMI treated with primary percutaneous coronary intervention. METHODS AND RESULTS: Cardiac magnetic resonance (CMR) was used to measure myocardial area at risk within 1-7 days and final infarct size 90±21 days after the...

  10. Assessment of team training in management of adverse acute events occurring during cardiopulmonary bypass procedure: a pilot study based on an animal simulation model (Fouilloux, Team training in cardiac surgery)

    OpenAIRE

    FOUILLOUX, Virginie; GSELL, Thibault; Lebel, S.; KREITMANN, B.; Berdah, Stéphane

    2014-01-01

    Successful cardiac surgery is highly dependent upon effective and efficient teamwork. Practical training and development will further enhance the team ability to react to a series of low-frequency occurring adverse events during cardiopulmonary bypass (CPB). One of our specialized educational programs focuses on training the whole team. This training is based on an original animal simulation model. The objective of this pilot study was to assess our method of training and learning in an attem...

  11. Clinical assessment and C-reactive protein (CRP), haptoglobin (Hp), and cardiac troponin I (cTnI) values of brachycephalic dogs with upper airway obstruction before and after surgery

    OpenAIRE

    Planellas, Marta; Cuenca, Rafaela; Tabar, Maria-Dolores; Bertolani, Coralie; Poncet, Cyrill; Closa, Josep M; Lorente, Juan; Cerón, José J.; Pastor, Josep

    2015-01-01

    Brachycephalic dogs have unique upper respiratory anatomy with abnormal breathing patterns that are similar to those in humans with obstructive sleep apnea syndrome (OSAS). The objectives of this multicenter prospective study were to assess the effects of surgical correction on clinical signs in dogs with brachycephalic airway obstructive syndrome (BAOS) and to evaluate the levels of several biomarkers [C-reactive protein (CRP); haptoglobin (Hp), and cardiac troponin I (cTnI)] used to determi...

  12. The ADOPT trial (Assessment of Efficacies of Cardiac Resynchronization Therapies (CRT-P/D for Heart Failure Patients in China: rationale, design, and end-points

    Directory of Open Access Journals (Sweden)

    Liu B

    2011-06-01

    Full Text Available Bing Liu1*, Fu Yi1*, Hongwei Cai2, Wenyi Guo1, Weijie Li1, Min Shen1, Jielai Xia3, Liwen Liu4, Haichang Wang1, on behalf of The ADOPT Study Steering Committee and Investigators1Department of Cardiology, Xijing Hospital, FMMU, Xi’an, China; 2Department of Information, School of Stomatology, FMMU, Xi’an, China; 3Department of Statistics, FMMU, Xi’an, China; 4Department of Ultrasound, Xijing Hospital, FMMU, Xi’an, ChinaClinicalTrials.gov number, NCT01018667*Both authors contributed equally to this workBackground: Cardiac resynchronization therapy (CRT is a novel nonpharmacological treatment for patients with chronic heart failure (CHF. Some clinical trials conducted in Western countries have demonstrated that CRT could improve CHF patients’ symptoms and reduce mortality. However, due to the differences in economic and social conditions as well as inconsistencies in CHF etiologies between China and Western countries, there is an urgent need to conduct a large-scale CRT clinical study in Chinese patients with CHF. The ADOPT Trial (Assessment of Efficacies of Cardiac Resynchronization Therapies (CRT-P/D for Heart Failure Patients in China is designed to observe whether CRT can further improve syptoms and reduce mortality in Chinese patients in addition to optimal pharmalogical therapy.Methods: The ADOPT study is a prospective, nested, case-controlled, open-label clinical trial. About 40 centers across China participate in this study with a planned 800 Chinese cases to be enrolled. All patients will receive optimal medical treatment. Patients who have successful CRT-P/D implant will be assigned to the CRT group. According to the baseline evaluation, matched cases will be selected from the enrolled optimal pharmaceutical therapy alone group (Group for Selection. After successful match, the cases in Group for Selection enter into follow-up and become the control group. The unmatched cases in the Group for Selection will be removed. If patients

  13. Optoacoustic measurement of central venous oxygenation for assessment of circulatory shock: clinical study in cardiac surgery patients

    Science.gov (United States)

    Petrov, Irene Y.; Prough, Donald S.; Kinsky, Michael; Petrov, Yuriy; Petrov, Andrey; Henkel, S. Nan; Seeton, Roger; Salter, Michael G.; Esenaliev, Rinat O.

    2014-03-01

    Circulatory shock is a dangerous medical condition, in which blood flow cannot provide the necessary amount of oxygen to organs and tissues. Currently, its diagnosis and therapy decisions are based on hemodynamic parameters (heart rate, blood pressure, blood gases) and mental status of a patient, which all have low specificity. Measurement of mixed or central venous blood oxygenation via catheters is more reliable, but highly invasive and associated with complications. Our previous studies in healthy volunteers demonstrated that optoacoustic systems provide non-invasive measurement of blood oxygenation in specific vessels, including central veins. Here we report our first results of a clinical study in coronary artery bypass graft (CABG) surgery patients. We used a medical-grade OPO-based optoacoustic system developed in our laboratory to measure in real time blood oxygenation in the internal jugular vein (IJV) of these patients. A clinical ultrasound imaging system (GE Vivid e) was used for IJV localization. Catheters were placed in the IJV as part of routine care and blood samples taken via the catheters were processed with a CO-oximeter. The optoacoustic oxygenation data were compared to the CO-oximeter readings. Good correlation between the noninvasive and invasive measurements was obtained. The results of these studies suggest that the optoacoustic system can provide accurate, noninvasive measurements of central venous oxygenation that can be used for patients with circulatory shock.

  14. Flow

    DEFF Research Database (Denmark)

    Knoop, Hans Henrik

    2006-01-01

    FLOW. Orden i hovedet på den fede måde Oplevelsesmæssigt er flow-tilstanden kendetegnet ved at man er fuldstændig involveret, fokuseret og koncentreret; at man oplever stor indre klarhed ved at vide hvad der skal gøres, og i hvilket omfang det lykkes; at man ved at det er muligt at løse opgaven...

  15. Assessment model validity document. NAMMU: A program for calculating groundwater flow and transport through porous media

    International Nuclear Information System (INIS)

    NAMMU is a computer program for modelling groundwater flow and transport through porous media. This document provides an overview of the use of the program for geosphere modelling in performance assessment calculations and gives a detailed description of the program itself. The aim of the document is to give an indication of the grounds for having confidence in NAMMU as a performance assessment tool. In order to achieve this the following topics are discussed. The basic premises of the assessment approach and the purpose of and nature of the calculations that can be undertaken using NAMMU are outlined. The concepts of the validation of models and the considerations that can lead to increased confidence in models are described. The physical processes that can be modelled using NAMMU and the mathematical models and numerical techniques that are used to represent them are discussed in some detail. Finally, the grounds that would lead one to have confidence that NAMMU is fit for purpose are summarised

  16. Assessment model validity document. NAMMU: A program for calculating groundwater flow and transport through porous media

    Energy Technology Data Exchange (ETDEWEB)

    Cliffe, K.A.; Morris, S.T.; Porter, J.D. [AEA Technology, Harwell (United Kingdom)

    1998-05-01

    NAMMU is a computer program for modelling groundwater flow and transport through porous media. This document provides an overview of the use of the program for geosphere modelling in performance assessment calculations and gives a detailed description of the program itself. The aim of the document is to give an indication of the grounds for having confidence in NAMMU as a performance assessment tool. In order to achieve this the following topics are discussed. The basic premises of the assessment approach and the purpose of and nature of the calculations that can be undertaken using NAMMU are outlined. The concepts of the validation of models and the considerations that can lead to increased confidence in models are described. The physical processes that can be modelled using NAMMU and the mathematical models and numerical techniques that are used to represent them are discussed in some detail. Finally, the grounds that would lead one to have confidence that NAMMU is fit for purpose are summarised.

  17. Receiver-Operating-Characteristic Analysis Reveals Superiority of Scale-Dependent Wavelet and Spectral Measures for Assessing Cardiac Dysfunction

    CERN Document Server

    Thurner, S; Lowen, S B; Teich, M C; Thurner, Stefan; Feurstein, Markus C.; Lowen, Steven B.; Teich, Malvin C.

    1998-01-01

    Receiver-operating-characteristic (ROC) analysis was used to assess the suitability of various heart rate variability (HRV) measures for correctly classifying electrocardiogram records of varying lengths as normal or revealing the presence of heart failure. Scale-dependent HRV measures were found to be substantially superior to scale-independent measures (scaling exponents) for discriminating the two classes of data over a broad range of record lengths. The wavelet-coefficient standard deviation at a scale near 32 heartbeat intervals, and its spectral counterpart near 1/32 cycles per interval, provide reliable results using record lengths just minutes long. A jittered integrate-and-fire model built around a fractal Gaussian-noise kernel provides a realistic, though not perfect, simulation of heartbeat sequences.

  18. Sexual Dysfunction before and after Cardiac Rehabilitation

    OpenAIRE

    Jörg Schumann; Zellweger, Michael J.; Marcello Di Valentino; Simone Piazzalonga; Andreas Hoffmann

    2010-01-01

    Background. The aim of this study was to assess sexual function before and after cardiac rehabilitation in relation to medical variables. Methods. Analysis of patients participating in a 12-week exercise-based outpatient cardiac rehabilitation program (OCR) between April 1999 and December 2007. Exercise capacity (ExC) and quality of life including sexual function were assessed before and after OCR. Results. Complete data were available in 896 male patients. No sexual activity at all was indic...

  19. Assessment on alien herbicide-resistant gene flow among crucifers by sexual compatibility

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xiangxiang; LU Weiping; QI Cunkou; PU Huiming; XIA Qiuxia; LU Dalei; LIU Geshan; WANG Youping

    2005-01-01

    Cross-pollination and high cross-compatibility are frequently found in many cruciferous plants, which implies that there might be potential risk of alien gene flow among crucifers. In this work, the alien glyphosate-resistant gene flow between GM (Genetically modified) rapeseed variety Q3 (Brassica napus) and 6 varieties from 5 cruciferous species was assessed by sexual compatibility through aniline blue fluorescence observation, manual cross, mentor pollination with the mixture pollen and DNA identification. The results indicated that the compatibility indices of two B. napus varieties, B. juncea var. multiceps Tsen et Lee and Chinese cabbage (B. chinensis) (as female) with Q3 (as male) were 16.15, 12.77, 2.345 and 0.85, respectively. F1 plants were examined by PCR and all of these samples were confirmed as positive. Crossing between Orychophragmus violaceus, Descurainia sophia (as female) and Q3 (as male) expressed high cross-incompatibility. Fluorescence microscope observation indicated that growing of pollen tube terminated at the upper 1/3 part of the style of O. violaceus and on the stigma surface of D. sophia. The mentor plants were further analyzed by PCR and all were shown to be negative. Under the neighboring growth and natural pollination conditions, the rates of gene flow to two B. napus varieties were 2.3278% and 2.1487%, respectively, B. juncea var. multiceps Tsen et Lee and Chinese cabbage were 1.0157% and 0.9236%, respectively. No gene flow was observed in O. violaceus and D. sophia. Frequency of gene flow was highly correlated with sexual compatibility. Due to possible alien gene flow among crucifers, special consideration and care should be taken to grow GM rapeseed.

  20. A three-pillar approach to assessing climate impacts on low flows

    Directory of Open Access Journals (Sweden)

    G. Laaha

    2015-12-01

    Full Text Available The objective of this paper is to present a new strategy for assessing climate impacts on low flows and droughts. The strategy is termed a three-pillar approach as it combines different sources of information. The first pillar, trend extrapolation, exploits the temporal patterns of observed low flows and extends them into the future. The second pillar, rainfall–runoff projections uses precipitation and temperature scenarios from climate models as an input to rainfall–runoff models to project future low flows. The third pillar, stochastic projections, exploits the temporal patterns of observed precipitation and air temperature and extends them into the future to drive rainfall–runoff projections. These pieces of information are combined by expert judgement based on a synoptic view of data and model outputs, taking the respective uncertainties of the methods into account. The viability of the approach is demonstrated for four example catchments from Austria that represent typical climate conditions in Central Europe. The projections differ in terms of their signs and magnitudes. The degree to which the methods agree depends on the regional climate and the dominant low flow seasonality. In the Alpine region where winter low flows dominate, trend projections and climate scenarios yield consistent projections of increasing low flows, although of different magnitudes. In the region north of the Alps, consistently small changes are projected by all methods. In the regions in the South and Southeast, more pronounced and mostly decreasing trends are projected but there is disagreement in the magnitudes of the projected changes. These results suggest that conclusions drawn from only one pillar of information would be highly uncertain. The three-pillar approach offers a systematic framework of combining different sources of information aiming at more robust projections than obtained from each pillar alone.