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Sample records for echocardiography doppler pulsed

  1. Color M-mode and pulsed wave tissue Doppler echocardiography

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    Møller, J E; Søndergaard, E; Poulsen, S H;

    2001-01-01

    To assess the association between color M-mode flow propagation velocity and the early diastolic mitral annular velocity (E(m)) obtained with tissue Doppler echocardiography and to assess the prognostic implications of the indexes, echocardiography was performed on days 1 and 5, and 1 and 3 months...

  2. Ecocardiografia modo Doppler pulsado em gatos clinicamente sadios Pulsed wave Doppler echocardiography in clinically healthy cats

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    R.O. Carvalho

    2006-06-01

    Full Text Available Estudou-se o fluxo sangüíneo através das quatro valvas cardíacas em 30 gatos clinicamente sadios, com idade entre um e cinco anos e peso médio de 4,08kg, por meio da ecocardiografia modo Doppler pulsado. Foram medidas a velocidade máxima e a velocidade média dos fluxos, e realizou-se uma análise qualitativa dos seus perfis. Os animais foram sedados pela combinação de quetamina (12mg/kg e acepromazina (0,04mg/kg, aplicados por via intramuscular. Observou-se correlação positiva entre os parâmetros avaliados e a freqüência cardíaca, com exceção daqueles medidos no fluxo da valva aórtica. Não se observou correlação entre velocidades máxima e média e freqüência cardíaca e entre aquelas e peso corporal, e não houve diferença entre sexos.Pulsed wave Doppler echocardiography was used to study blood flow across the cardiac valves in 30 five-year-old cats (average body weight = 4.08kg. Animals were sedated using a combination of ketamin (12mg/kg, IM and acepromazin (0.04mg/kg, IM. Peak and mean velocities were determined, and blood flow patterns were recorded at the four cardiac valves. All variables, except those characterizing aortic valve flow, were positively correlated with heart rate. Blood flow variables were not correlated, however, with body weight; and there were no differences between males and females.

  3. Transthoracic Doppler echocardiography to predict optimal tube pulsing window for coronary artery CT angiography

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    Sun, Gang, E-mail: cjr.sungang@vip.163.com [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Li, Min, E-mail: limin22000@yahoo.com.cn [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Jiang, Xiang-sen, E-mail: jiangxiangsen123@126.com [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Li, Li, E-mail: leely1976@yahoo.com.cn [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Peng, Zhao-hui, E-mail: zhaohuipeng_R@163.com [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Mu, Nan-nan, E-mail: munannan22000@sohu.com [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China)

    2012-09-15

    Rationale and objective: To evaluate the feasibility of transthoracic Doppler echocardiography to determine the optimal pulsing windows for CT coronary angiography to narrow the pulsing windows further, especially in higher heart rate. Materials and methods: Doppler was performed on 135 patients before CT scanning. For Doppler, the intervals with minimal motion were evaluated during both systole and diastole integrating electrocardiogram (ECG) intervals. For CT scanning, the retrospective ECG-gating was applied and the optimal reconstruction intervals were determined. The accuracy of Doppler analysis to predict the optimal reconstruction intervals was tested. The predicted length of pulsing windows was compared between Doppler analysis and traditional prospective ECG-gating protocol (heart rate ≦ 65 bpm, 60–76%; 66–79 bpm, 30–77%; ≧80 bpm, 31–47%). Results: According to Doppler analysis, the mean length of intervals with minimal motion in systole was 106.4 ± 39.2 ms and 125.2 ± 92.0 ms in diastole. When the intervals with minimal motion during diastole > 90 ms, the optimal reconstruction intervals were located at diastole; otherwise, at systole (P < 0.001). The optimal reconstruction intervals in 93.8% (132/135) patients could be predicted accurately by Doppler analysis. If the optimal reconstruction intervals predicted by Doppler were applied as the exposure windows, the mean length of pulsing windows should has been 105.2 ± 69.4 ms (range: 26.9–510.3 ms), which was significantly shorter than that of traditional prospective ECG-gating protocol (232.0 ± 120.2 ms, range: 93.2–427.3 ms, P < 0.001). Conclusion: Doppler can help detecting the optimal pulsing windows accurately. Prospective ECG-gating incorporating Doppler analysis may narrow pulsing windows significantly while maintaining image quality.

  4. Left ventricular radial colour and longitudinal pulsed-wave tissue Doppler echocardiography in 39 healthy domestic pet rabbits.

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    Casamian-Sorrosal, Domingo; Saunders, Richard; Browne, William; Elliot, Sarah; Fonfara, Sonja

    2014-10-01

    This paper reports radial colour and longitudinal mitral annulus pulsed-wave tissue Doppler findings in a large cohort of healthy, adult pet rabbits. Thirty-nine rabbits (22 Dwarf Lops, 14 French Lops and three Alaskans) underwent conscious echocardiography. The median age of the rabbits was 22 months and the median weight was 2.8 kg (Dwarf Lop 2.4 kg/French Lop 6.0 kg). Adequate radial colour and longitudinal pulsed-wave tissue Doppler traces were obtained in 100% and 85% of cases, respectively. Most systolic tissue Doppler parameters were significantly higher in French Lops than in Dwarf Lops. Separation of mitral inflow diastolic waves was present in 40% of cases using conventional spectral Doppler and in >60% of cases using pulsed-wave tissue Doppler which could be beneficial when evaluating diastolic function in rabbits. This study can be used as a reference for normal echocardiographic tissue Doppler values for adult rabbits undergoing conscious echocardiography in clinical practice.

  5. [The usefulness of range-gated pulsed Doppler echocardiography. A review (author's transl)].

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    Lange, L; Allen, H D; Goldberg, S J; Sahn, D J

    1979-03-01

    Single-crystal RGPD Echocardiography has clearly become a useful noninvasive ultrasonic method which enlarges the capabilities of investigating the heart. Recording of flow direction and showing disturbed flow allows additional clarification and confirmation of various diagnoses. This single-crystal technique does not allow flow quantification at the present time. The TIH and auditory signal displays of Doppler shift as presently utilized in commercial devices allow qualitative observation but require much experience in test performance and evaluation. The future here is probably in the area of spectral analysis. Present instrumentation employs M-mode echo for Doppler sample localization. Drawbacks include inprecise sample beam localization and non-variable sample volume size. Further, standardization of the Doppler signal is necessary. Combination with 2-D echo in the future will allow more precise sample beam localization and accuracy in flow quantification. The latter area has particular promise and is under investigation but is not yet commercially available.

  6. An evaluation of range gated pulsed Doppler echocardiography for detecting pulmonary outflow tract obstruction in d-transposition of the great vessels.

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    Areias, J C; Goldberg, S J; Spitaels, S E; de Villeneuve, V H

    1978-10-01

    The aim of this study was to determine the accuracy of range gated pulsed Doppler (RGPD) echocardiography for detecting obstruction to the pulmonary outflow tract in children with d-transposition of the great vessels (d-TGV). Twenty-one children were randomly selected for those available with d-TGV and were studied by precordial and suprasternal RGPD echocardiography. Three were excluded, leaving a population of 18 subjects. The exclusive criterion used to judge the RGPD results was the output of the time interval histogram (TIH). Coherence of the TIH was considered to represent laminar flow. Dispersion of the TIH was considered evidence of flow disturbance and obstruction to the outflow tract. With the range gating feature, the first site of disturbance could be localized. Information was handled by a technique that decreased bias. RGPD results were then compared to diagnoses of the outflow tract established at cardiac catheterization or operation. Comparison of these results indicated that all seven children with obstruction were correctly identified by RGPD study, and the level of the first obstruction was correctly identified. With one exception, all children without pulmonary obstruction were correctly identified by the examination.

  7. Usefulness of pulse-wave doppler tissue sampling and dobutamine stress echocardiography for identification of false positive inferior wall defects in SPECT

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    Altinmakas, S. [Maltepe Univ., Istanbul (Turkey) Medical Faculty; Dagdeviren, B.; Turkmen, M.; Gursurer, M.; Say, B.; Tezel, T.; Ersek, B.

    2000-03-01

    False positive inferior wall perfusion defects restrict the accuracy of SPECT in diagnosis of coronary artery disease (CAD). Pulse-Wave Tissue Doppler (PWTD) has been recently proposed to assess regional wall motion velocities. The objectives of this study were to evaluate the presence of CAD by using PWTD during dobutamine stress echocardiography (DSE) in patients with an inferior perfusion defect detected by SPECT and compare PWTD parameters of normal cases with patients who had inferior perfusion defect and CAD. Sixty-five patients (mean age 58{+-}8 years, 30 men) with a normal LV systolic function at rest according to echocardiographic evaluation with an inferior ischemia determined by SPECT and a control group (CG) of 34 normal cases (mean age 56{+-}7 years, 16 men) were included in this study. All patients underwent a standard DSE (up to 40 {mu}g/kg/min with additional atropine during sub-maximum heart rate responses). Pulse-wave Doppler tissue sampling of inferior wall was performed in the apical 2-chamber view at rest and stress. The coronary angiography was performed within 24 hours. The results were evaluated for the prediction of significant right coronary artery (RCA) and/or left circumflex coronary artery (CX) with narrowing ({>=}50% diameter stenosis, assessed by quantitative coronary angiography). It was observed that the peak stress mean E/A ratio was lower in patients with CAD when compared to patients without CAD (0.78{+-}0.2 versus 1.29{+-}0.11 p<0.0001). Also the peak stress E/A ratio of normal cases was significantly higher than patients who had CAD (1.19{+-}0.3 versus 0.78{+-}0.2 p<0.0001). When the cut off point for the E/A ratio was determined as 1, the sensitivity and specificity of dobutamine stress PWTD E/A were 89% and 86%, respectively. The peak stress E/A ratio was higher than 1 in all patients with a false positive perfusion defect. Systolic S velocity increase during DSE was significantly lower in patients with CAD (54%{+-}17 versus

  8. Pulse subtraction Doppler

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    Mahue, Veronique; Mari, Jean Martial; Eckersley, Robert J.; Caro, Colin G.; Tang, Meng-Xing

    2010-01-01

    Recent advances have demonstrated the feasibility of molecular imaging using targeted microbubbles and ultrasound. One technical challenge is to selectively detect attached bubbles from those freely flowing bubbles and surrounding tissue. Pulse Inversion Doppler is an imaging technique enabling the selective detection of both static and moving ultrasound contrast agents: linear scatterers generate a single band Doppler spectrum, while non-linear scatterers generate a double band spectrum, one being uniquely correlated with the presence of contrast agents and non-linear tissue signals. We demonstrate that similar spectrums, and thus the same discrimination, can be obtained through a Doppler implementation of Pulse Subtraction. This is achieved by reconstructing a virtual echo using the echo generated from a short pulse transmission. Moreover by subtracting from this virtual echo the one generated from a longer pulse transmission, it is possible to fully suppress the echo from linear scatterers, while for non-linear scatterers, a signal will remain, allowing classical agent detection. Simulations of a single moving microbubble and a moving linear scatterer subject to these pulses show that when the virtual echo and the long pulse echo are used to perform pulsed Doppler, the power Doppler spectrum allows separation of linear and non-linear moving scattering. Similar results are obtained on experimental data acquired on a flow containing either microbubble contrast agents or linear blood mimicking fluid. This new Doppler method constitutes an alternative to Pulse Inversion Doppler and preliminary results suggest that similar dual band spectrums could be obtained by the combination of any non-linear detection technique with Doppler demodulation.

  9. Pulse Doppler radar

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    Alabaster, Clive

    2012-01-01

    This book is a practitioner's guide to all aspects of pulse Doppler radar. It concentrates on airborne military radar systems since they are the most used, most complex, and most interesting of the pulse Doppler radars; however, ground-based and non-military systems are also included. It covers the fundamental science, signal processing, hardware issues, systems design and case studies of typical systems. It will be a useful resource for engineers of all types (hardware, software and systems), academics, post-graduate students, scientists in radar and radar electronic warfare sectors and milit

  10. Karakteristik Aliran Darah pada Katup Semilunar Aorta Anjing Kampung yang Dinilai dengan Pulsed Wave Doppler Ekhokardiografi (CHARACTERISTICS OF BLOOD FLOW IN SEMILUNAR AORTA VALVE OF MONGREL DOG ASSESSED BY PULSED WAVE DOPPLER ECHOCARDIOGRAPHY

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    Deni Noviana

    2014-04-01

    Full Text Available The purpose of this study was to determine the characteristics of blood flow which passed through theaortic valve of normal Indonesian mongrel dogs using trans-thoracic Pulsed Wave Doppler (PWDechocardiography. Eight (8 adult dogs (three male dogs and 5 female dogs with an average age 3.31 ± 0.59years and average body weight 12.45 ± 1.30 kg were used in the study. Trans-thoracic PWD echocardiographyexaminations were performed in conscious/unsedated animals at the left lateral recumbence position. Theinstruments used in this study were: i two dimensional ultrasound device and ii phased array transducersmall foot print with 3.7 – 5.0 MHz frequency. Six elements of PWD were measured: i heart rate (HR; iipeak velocity (Vpeak; iii velocity time integral (VTI; iv mean pressure gradient (MPG; v pulsatilityindex (PI; and vi ratio of systole-diastole (S/D. Results showed the typically characteristics of blood flowin semilunar aorta valve is demonstrated by the only one peak wave (peak velocity = Vpeak upon examinationby placing the Doppler scan volume right on the aorta valve. In general, all six elements of PWD measuredwere found to be higher in female dogs compared to male dogs. However, these differences were notstatistically significant (P>0.05.

  11. Doppler echocardiography in normal functioning valve prostheses.

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    Cha, R; Yang, S S; Salvucci, T; DiBlasi, S

    1994-09-01

    Even though there has been some criticism regarding the Doppler evaluation in prosthetic valves because of inter-observer and intra-observer variability, among other factors, and Doppler study has a tendency to have falsely high gradients compared to invasive studies, especially mechanical aortic prostheses, Doppler evaluation can provide reliable hemodynamic information about valve function. This test may be particularly useful if used serially, when baseline values are known. Doppler measurement of gradient and valve area has an expected normal range that is specific for the prosthetic type, size, anatomical position, and chronological age. Clearly, a database involving these aspects is needed to provide a more accurate normal range. This study is intended to provide guidance for echocardiographers.

  12. Assessment of right ventricular systolic function by tissue Doppler echocardiography

    DEFF Research Database (Denmark)

    Kjærgaard, Jesper

    2012-01-01

    myocardial velocities, but no changes in SR, strain or isovolumic acceleration could be observed [II and III]. Tissue Doppler echocardiography of the RV free wall in non-massive pulmonary embolism quantifies degree of RV dysfunction, and supports the existence of the McConnell sign of mid-ventricular RV...... structure including significant dilatation, but is well tolerated with only mild reduction in measures of global RV systolic function as estimated by 2D echocardiography in an experimental animal model. Regional RV myocardial function is also only mildly reduced. Also no differences in global or regional RV......This thesis summarizes a series of studies performed in order to assess the clinical usefulness of a novel echocardiographic technology that allows non-invasive assessment of regional right ventricular myocardial velocities and deformation: tissue Doppler echocardiography. While the technology...

  13. Cancer therapy and cardiotoxicity: The need of serial Doppler echocardiography

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    Pardo Moira

    2007-01-01

    Full Text Available Abstract Cancer therapy has shown terrific progress leading to important reduction of morbidity and mortality of several kinds of cancer. The therapeutic management of oncologic patients includes combinations of drugs, radiation therapy and surgery. Many of these therapies produce adverse cardiovascular complications which may negatively affect both the quality of life and the prognosis. For several years the most common noninvasive method of monitoring cardiotoxicity has been represented by radionuclide ventriculography while other tests as effort EKG and stress myocardial perfusion imaging may detect ischemic complications, and 24-hour Holter monitoring unmask suspected arrhythmias. Also biomarkers such as troponine I and T and B-type natriuretic peptide may be useful for early detection of cardiotoxicity. Today, the widely used non-invasive method of monitoring cardiotoxicity of cancer therapy is, however, represented by Doppler-echocardiography which allows to identify the main forms of cardiac complications of cancer therapy: left ventricular (systolic and diastolic dysfunction, valve heart disease, pericarditis and pericardial effusion, carotid artery lesions. Advanced ultrasound tools, as Integrated Backscatter and Tissue Doppler, but also simple ultrasound detection of "lung comet" on the anterior and lateral chest can be helpful for early, subclinical diagnosis of cardiac involvement. Serial Doppler echocardiographic evaluation has to be encouraged in the oncologic patients, before, during and even late after therapy completion. This is crucial when using anthracyclines, which have early but, most importantly, late, cumulative cardiac toxicity. The echocardiographic monitoring appears even indispensable after radiation therapy, whose detrimental effects may appear several years after the end of irradiation.

  14. Pulsed Doppler echocardiographic analysis of mitral regurgitation after myocardial infarction.

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    Loperfido, F; Biasucci, L M; Pennestri, F; Laurenzi, F; Gimigliano, F; Vigna, C; Rossi, E; Favuzzi, A; Santarelli, P; Manzoli, U

    1986-10-01

    In 72 patients with previous myocardial infarction (MI), mitral regurgitation (MR) was assessed by pulsed-wave Doppler echocardiography and compared with physical and 2-dimensional echocardiographic findings. MR was found by Doppler in 29 of 42 patients (62%) with anterior MI, 11 of 30 (37%) with inferior MI (p less than 0.01) and in none of 20 normal control subjects. MR was more frequent in patients who underwent Doppler study 3 months after MI than in those who underwent Doppler at discharge (anterior MI = 83% vs 50%, p less than 0.01; inferior MI = 47% vs 27%, p = not significant). Of 15 patients who underwent Doppler studies both times, 3 (all with anterior MI) had MR only on the second study. Of the patients with Doppler MR, 12 of 27 (44%) with a left ventricular (LV) ejection fraction (EF) greater than 30% and 1 of 13 (8%) with an EF of 30% or less (p less than 0.01) had an MR systolic murmur. Mitral prolapse or eversion and papillary muscle fibrosis were infrequent in MI patients, whether or not Doppler MR was present. The degree of Doppler MR correlated with EF (r = -0.61), LV systolic volume (r = 0.47), and systolic and diastolic mitral anulus circumference (r = 0.52 and 0.51, respectively). Doppler MR was present in 24 of 28 patients (86%) with an EF of 40% or less and in 16 of 44 (36%) with EF more than 40% (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Doppler echocardiography and myocardial dyssynchrony: a practical update of old and new ultrasound technologies

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    Galderisi Maurizio

    2007-09-01

    Full Text Available Abstract Morbidity and mortality rates are higher in patients with severe left ventricular (LV systolic dysfunction and ECG-derived prolonged QRS interval than in those with normal QRS duration. QRS duration is currently used on the grounds that it reflects the presence of ventricular dyssynchrony. However, 30–40% of patients selected on the basis of a prolonged QRS do not receive benefit by cardiac resynchronization therapy (CRT since they do not show any significant inverse LV remodeling and QRS duration does not accurately distinguish responders to CRT. Consequently, mechanical dyssynchrony (particularly intra-ventricular dyssynchrony seems to be much more important than electrical dyssinchrony. Pre- and post-echocardiographic assessment should require the combination of conventional and specific applications ranging from M-mode and pulsed/continuous Doppler, to pulsed Tissue Doppler, the off-line analysis of colour Tissue Velocity Imaging, Strain Rate Imaging, and real time three-dimensional reconstruction However, there is not no consensus about the best approach and the best ultrasound parameter for selecting candidates to CRT and ECG representation of abnormal cardiac conduction still remains as the main criterion in guidelines. This review is a practical update of ultrasound methods and measurements of atrio-ventricular, inter-ventricular and intra-ventricular dyssynchrony and describes experiences which used either conventional Doppler echocardiography and more advanced techniques. By these experiences, the global amount of LV dyssynchrony seems to be critical: the greater intra-ventricular dyssynchrony, the higher the possibility of significant LV inverse remodeling. After CRT, it is necessary also to evaluate the optimal atrio-ventricular delay and ventricular-ventricular delay setting that maximizes LV systolic function.

  16. Transthoracic Doppler echocardiography – noninvasive diagnostic window for coronary flow reserve assessment

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    Dimitrow Paweł

    2003-04-01

    Full Text Available Abstract This review focuses on transthoracic Doppler echocardiography as noninvasive method used to assess coronary flow reserve (CFR in a wide spectrum of clinical settings. Transthoracic Doppler echocardiography is rapidly gaining appreciation as popular tool to measure CFR both in stenosed and normal epicardial coronary arteries (predominantly in left anterior descending coronary artery. Post-stenotic CFR measurement is helpful in: functional assessment of moderate stenosis, detection of significant or critical stenosis, monitoring of restenosis after revascularization. In the absence of stenosis in the epicardial coronary artery, decreased CFR enable to detect impaired microvascular vasodilatation in: reperfused myocardial infarct, arterial hypertension with or without left ventricular hypertrophy, diabetes mellitus, hypercholesterolemia, syndrome X, hypertrophic cardiomyopathy. In these diseases, noninvasive transthoracic Doppler echocardiography allows for serial CFR evaluations to explore the effect of various pharmacological therapies.

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

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

    2002-04-01

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

  18. Assessment of myocardial strain and strain rate by tissue doppler echocar-diography

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    Ekimova N.A.

    2013-03-01

    Full Text Available The objective of the article is to review the current data on the method of quantitative evaluation of cardiac mechanics — assessment of myocardial strain and strain rate according to the results of the tissue Doppler echocardiography and prospects of its clinical application.

  19. 21 CFR 892.1550 - Ultrasonic pulsed doppler imaging system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ultrasonic pulsed doppler imaging system. 892.1550... system. (a) Identification. An ultrasonic pulsed doppler imaging system is a device that combines the features of continuous wave doppler-effect technology with pulsed-echo effect technology and is intended...

  20. Serial changes of left ventricular filling flow pattern on doppler echocardiography concerning perfusion recovery and restenosis after successful coronary angioplasty

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    Han, Xirui; Yonekura, Shuji; Nakata, Tomoaki; Tsuchihashi, Kazufumi; Shimamoto, Kazuaki [Sapporo Medical Univ. (Japan)

    1997-10-01

    We tested whether diastolic indices on pulse Doppler echocardiography, i.e., the peak early diastolic filling velocity (E, cm/sec), the acceleration slope of E (AC, cm/sec{sup 2}), and the ratio of peak diastolic filling to peak atrial filling velocity (E/A) might be changed early after PTCA in relation with perfusion recovery on thallium scintigraphy. Additionally, the clinical usefulness of these indices for the detection of restenosis after PTCA was also examined in 35 patients, including 12 patients with old Q wave myocardial infarction (OMI), on whom PTCA had been successfully performed. Perfusion abnormalities on stress {sup 201}Tl scintigraphy was quantitatively evaluated by severity score (SS) and extent score (ES). In patients with angina pectoris, early recoveries of values on E, AC, and E/A were observed, but not in patients with 0MI. The percent changes of these indices had significant correlations with changes of SS in scintigraphy. In the chronic period, recovery of values E, AC, and E/A were also seen in OMI without restenosis, but not in those with restenosis. Percent E and %A{<=}105 could predict restenosis by sensitivity 100% and specificity 94.4% in all subjects. These results reveal that a follow-up of the indices on pulse Doppler echocardiography has clinical usefulness in the detection not only of functional recovery of left ventricular diastolic function, but also of restenosis after successful PTCA. (K.H.)

  1. Cardiac output by Doppler echocardiography in the premature baboon: comparison with radiolabeled microspheres.

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

    1991-04-01

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

  2. Assessment of right ventricular systolic function by tissue Doppler echocardiography

    DEFF Research Database (Denmark)

    Kjærgaard, Jesper

    2012-01-01

    is a promising tool for improving our understanding of right ventricular hemodynamics, several aspects of the technology must be evaluated. The accuracy and reproducibility of the technology is evaluated in vitro, and normal values, impact of changes in loading of the right ventricle, response to exercise...... gained from other quantitative echocardiographic measures of LV and RV function and pressure [VI]. Changes in tissue Doppler based measures of RV systolic function can be used to monitor the effect of selective vasodilation by phosphodiestares-5 inhibition in hypoxic pulmonary hypertension and exercise...... in normal individuals. Phosphodiestares-5 inhibition by sildenafil may predominantly be effective during hypoxia in resting conditions, and may improve the blunted response in RV contractility seen with exercise in hypoxia [VII]. Reduced RV free wall deformation can be quantified by tissue Doppler...

  3. Detection and visualization to Doppler sensitive sonar pulses

    NARCIS (Netherlands)

    Bertrand, D.B.; IJsselmuide, S.P. van; Beerens, S.P.

    2006-01-01

    In anti-submarine warfare, the use of Doppler sensitive sonar pulses is common practice. In particular, the wideband Doppler sensitive PTFM pulse (Pulse Train Frequency Modulation) is a powerful tool for detection in reverberation limited conditions. Nevertheless, this pulse is not operationally

  4. [Correlation of the transaortic gradient determined with doppler echocardiography versus catheterization in patients with aortic stenosis].

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    Illescas, J; Enciso, R; Vidrio, M; de la Torre, N; Baduí, E

    1991-01-01

    The purpose of this report is to evaluate the reliability of a non-invasive estimation of a transaortic gradient in patients with valvular aortic stenosis by doppler echocardiography. We compared the transvalvular gradients obtained by cardiac catheterization (invasive) versus the estimation by non-invasive technique such as continuous-wave doppler in 30 consecutive patients with valvular aortic stenosis. When compared the peak velocity (Vmax) of the aortic jet versus the gradient obtained by cardiac catheterization we found a correlation coefficient (r) of 0.83 and when compared the gradient obtained by both methods we found an r value of 0.85. These results show that the calculations of aortic gradient by echo-doppler, are reliable. Besides this method allowed us to establish the correct diagnosis and to follow up these patients.

  5. Ventricular structure and function in children with sickle cell disease using conventional and tissue Doppler echocardiography.

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    Eddine, Ahmad Charaf; Alvarez, Ofelia; Lipshultz, Steven E; Kardon, Richard; Arheart, Kristopher; Swaminathan, Sethuraman

    2012-05-01

    Conventional 2-dimensional, M-mode, and spectral Doppler echocardiographic techniques have documented abnormal ventricular function in adults with sickle cell disease (SCD), but assessments in children are conflicting. Tissue Doppler echocardiography (TDE) provides additional information about myocardial function. Two-dimensional, M-mode, tricuspid regurgitation jet velocity (TRJV) data, and tissue Doppler echocardiographically derived myocardial velocity measurements of left ventricular (LV) and right ventricular function were taken from children with SCD compared to those of similar healthy historical controls and correlated with clinical characteristics and hemoglobin levels. Compared to 55 controls, 54 children with SCD (mean age 14.2 years, range 6 to 21) had a larger left ventricle, greater LV mass, and higher LV fractional shortening; 30% had increased pulmonary artery pressure (TRJV ≥2.5 m/s). Conventional echocardiographic measurements of LV systolic function and spectral Doppler measurements of LV and right ventricular diastolic function were essentially normal, but TDE indicated that 31% of SCD children had evidence of LV diastolic dysfunction (peak early diastolic velocity of LV inflow Doppler/peak early diastolic velocity at lateral mitral valve annulus >8), a finding that correlated with lower hemoglobin levels. Although decreasing hemoglobin levels in children with SCD correlated with LV hypertrophy, LV dilation, and LV diastolic dysfunction, long-term transfusion or hydroxyurea therapy did not affect these measurements. In conclusion, 1/3 of children with SCD had tissue Doppler echocardiographic evidence of LV diastolic dysfunction, which was correlated with hemoglobin levels. Adding serial assessments of ventricular function with TDE to conventional echocardiography may detect early cardiac changes, especially in children with severe anemia.

  6. Evaluation of Right Ventricular Function by Tissue Doppler Echocardiography in Asthmatic Children

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    Mehdi Ghaderian

    2016-11-01

    Full Text Available BackgroundAsthma is the most chronic inflammatory disorder of the airways in children and asthmatic patients can experience cardiac dysfunction, pulmonary hypertension and finally cor pulmonale later in life. We aimed to investigate Right Ventricular (RV functions in asthmatic children by conventional and tissue Doppler echocardiography (TDE.Materials and Methods Pulmonary function tests, conventional and TDE examinations were performed on 42 asthmatic and 42 age- and gender matched healthy controls subjects (n=42.Results Compared with healthy children the RV wall was statistically thicker among asthmatic patients (P= 0.01. Conventional echocardiography had not significant difference between cases and controls, but TDE had significant difference between these two groups. Peak E’ velocity, A’ velocity, E’/A’ ratio and S’ in lateral and medial sites of tricuspid annulus valve, were significantly differ from control group in our patients (P

  7. Repeatability, variability and reference values of pulsed wave Doppler echocardiographic measurements in healthy Saanen goats

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    Leroux Aurélia A

    2012-10-01

    Full Text Available Abstract Background Pulsed wave (PW Doppler echocardiography has become a routine non invasive cardiac diagnostic tool in most species. However, evaluation of intracardiac blood flow requires reference values, which are poorly documented in goats. The aim of this study was to test the repeatability, the variability, and to establish the reference values of PW measurements in healthy adult Saanen goats. Using a standardised PW Doppler echocardiographic protocol, 10 healthy adult unsedated female Saanen goats were investigated three times at one day intervals by the same observer. Mitral, tricuspid, aortic and pulmonary flows were measured from a right parasternal view, and mitral and aortic flows were also measured from a left parasternal view. The difference between left and right side measurements and the intra-observer inter-day repeatability were tested and then the reference values of PW Doppler echocardiographic parameters in healthy adult female Saanen goats were established. Results As documented in other species, all caprine PW Doppler parameters demonstrated a poor inter-day repeatability and a moderate variability. Tricuspid and pulmonary flows were best evaluated on the right side whereas mitral and aortic flows were best obtained on the left side, and reference values are reported for healthy adult Saanen goats. Conclusions PW Doppler echocardiography allows the measurement of intracardiac blood flow indices in goats. The reference values establishment will help interpreting these indices of cardiac function in clinical cardiac cases and developing animal models for human cardiology research.

  8. Doppler echocardiography imaging in detecting multi-valvular lesions: a clinical evaluation in children with acute rheumatic fever.

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    Pushpa Shivaram

    Full Text Available RATIONALE: Doppler echocardiography has been demonstrated to be accurate in diagnosing valvular lesions in rheumatic heart disease (RHD when compared to clinical evaluation alone. OBJECTIVE: To perform Doppler echocardiography in children clinically diagnosed by the Jones criteria to have acute rheumatic fever (ARF, and to then compare the effectiveness of echo in detecting single/multi-valvular lesions with that of the initial clinical evaluation. METHODS AND RESULTS: We enrolled 93 children who were previously diagnosed with ARF by clinical examination. Presence of valvular lesions were enlisted, first by clinical auscultation, and then by performing Doppler echocardiography. We found that Doppler echocardiography was a sensitive technique, capable of detecting valvular lesions that were missed by clinical auscultation alone. Echocardiography of patients with carditis revealed mitral regurgitation to be the most common lesion present (53 patients, 56.98%, followed by aortic regurgitation in 21 patients (22.6%. The difference between clinical and echocardiographic diagnosis in ARF children with carditis was statistically significant for mitral regurgitation, aortic regurgitation and tricuspid regurgitation. Clinical auscultation alone revealed 4 cases of mitral stenosis, 39 mitral regurgitation, 14 aortic regurgitation, 9 tricuspid regurgitation; in contrast, echo revealed 5 cases of mitral stenosis, 53 mitral regurgitation, 21 aortic regurgitation, 18 tricuspid regurgitation. CONCLUSION: Doppler echocardiography is a more sensitive technique for detecting valvular lesions. In the setting of ARF, echo enables a 46.9% higher detection level of carditis, as compared to the clinical examination alone. Echo was very significant in detecting regurgitation lesions, especially for cases of tricuspid regurgitation in the setting of multivalvular involvement. The results of our study are in accordance with previous clinical studies, all of which clearly

  9. Myocardial Strain and Strain Rate Imaging: Comparison between Doppler Derived Strain Imaging and Speckle Tracking Echocardiography

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    Anita Sadeghpour

    2013-05-01

    Full Text Available Regional myocardial function has been traditionally assessed by visual estimation (1. Echocardiographic strain imaging which is known as deformation imaging, has been emerged as a quantitative technique to accurately estimate regional myocardial function and contractility. Currently, strain imaging has been regarded as a research tool in the most echocardiography laboratories. However, in recent years, strain imaging has gain momentum in daily clinical practice (2. The following two techniques have dominated the research arena of echocardiography: (1 Doppler based tissue velocity measurements, frequently referred to tissue Doppler or myocardial Doppler, and (2 speckle tracking on the basis of displacement measurements (3. Over the past two decades, Tissue Doppler Imaging (TDI and Doppler –derived strain (S and strain rate (SR imaging were introduced to quantify regional myocardial function. However, Doppler–derived strain variables faced criticisms, with regard to the angle dependency, noise interference, and substantial intraobserver and interobserver variability. The angle dependency is the major weakness of Doppler based methodology; however, it has the advantage of online measurements of velocities and time intervals with excellent temporal resolution, which is essential for the assessment of ischemia (4. Speckle-tracking echocardiography (STE or Non Doppler 2D strain echocardiography is a relatively new, largely angle-independent technique that analyzes motion by tracking natural acoustic reflections and interference patterns within an ultrasonic window. The image-processing algorithm tracks elements with approximately 20 to 40 pixels containing stable patterns and are described as ‘‘speckles’’ or ‘‘fingerprints’’. The speckles seen in grayscale B-mode (2D images are tracked consecutively frame to frame (5, 6. Assessment of 2D strain by STE is a semiautomatic method that requires definition of the myocardium

  10. Cardiovascular assessment of patients with Ullrich-Turner's Syndrome on Doppler echocardiography and magnetic resonance imaging

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    Castro Ana Valéria Barros de

    2002-01-01

    Full Text Available OBJECTIVE: To assess the cardiovascular features of Ullrich-Turner's syndrome using echocardiography and magnetic resonance imaging, and to correlate them with the phenotype and karyotype of the patients. The diagnostic concordance between the 2 methods was also assessed. METHODS: Fifteen patients with the syndrome were assessed by echocardiography and magnetic resonance imaging (cardiac chambers, valves, and aorta. Their ages ranged from 10 to 28 (mean of 16.7 years. The karyotype was analyzed in 11 or 25 metaphases of peripheral blood lymphocytes, or both. RESULTS: The most common phenotypic changes were short stature and spontaneous absence of puberal development (100%; 1 patient had a cardiac murmur. The karyotypes detected were as follows: 45,X (n=7, mosaics (n=5, and deletions (n=3. No echocardiographic changes were observed. In regard to magnetic resonance imaging, coarctation and dilation of the aorta were found in 1 patient, and isolated dilation of the aorta was found in 4 patients. CONCLUSION: The frequencies of coarctation and dilation of the aorta detected on magnetic resonance imaging were similar to those reported in the literature (5.5% to 20%, and 6.3% to 29%, respectively. This confirmed the adjuvant role of magnetic resonance imaging to Doppler echocardiography for diagnosing cardiovascular alterations in patients with Ullrich-Turner's syndrome.

  11. Evaluation and prognostic significance of left ventricular diastolic function assessed by Doppler echocardiography in the early phase of a first acute myocardial infarction

    DEFF Research Database (Denmark)

    Poulsen, S H; Jensen, S E; Gøtzsche, O

    1997-01-01

    deceleration time development of congestive heart failure during the first week following a first acute myocardial infarction. CONCLUSION: Assessment of left ventricular diastolic function complements measurements of systolic function......AIM: To study the prognostic significance of left ventricular diastolic function evaluated by transmitral and pulmonary venous flow velocities obtained in the early phase of a first acute myocardial infarction in relation to later development of congestive heart failure. METHODS: Pulsed Doppler...... echocardiography of transmitral and pulmonary venous flow was assessed in 65 consecutive patients with a first myocardial infarction within 1 h of arrival in the coronary care unit. RESULTS: A univariate regression analysis identified age, left ventricular ejection fraction

  12. Evaluation of the Severity of Mitral Valvular Regurgitation with Doppler Echocardiography Using Proximal Flow Convergence Method

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    Pinjari A. Khayum

    2009-01-01

    Full Text Available Problem statement: Valvular regurgitation is recognized as the central cause of morbidity and mortality. Even though the clinician can detect the presence of regurgitation by mere physical examination; diagnostic methods become inevitable while estimating the severity of valvular regurgitation and in the transformation of cardiac chambers as in reaction to the volume overload condition. Lately, a promising new technology, the Echocardiography with Doppler is found to facilitate the non-invasive recognition and assessment of the severity and etiology of valvular regurgitation. Accurate measurements of regurgitant volume in patients is of utmost importance since it aids in the estimation of the progression of the disease which in turn is vital for determining the optimal time for surgical repair or replacement. Approach: Color space conversion and anisotropic diffusion segmentation techniques are utilized in this study for the pre-processing stage of the quantification of mitral regurgitation. Flow field measurements are carried out with the aid of proximal flow convergence method. Results: A calculated value of flow rate, regurgitant orifice area, regurgitant fraction and the regurgitant volume for a regurgitant orifice in the cardiovascular system are obtained from the potential Color Doppler visualization of the flow convergence region. Conclusion: The research proposed provides a significant assessment of the echocardiographic and Doppler techniques employed in the evaluation of mitral valvular regurgitation in the patients. Additionally it also proffers the estimation of mildness, severity and eccentricity of mitral valvular regurgitation on basis of the scientific literature and a consensus of a panel of experts.

  13. 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

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    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.

  14. Structural and functional characteristics of rat hearts with and without myocardial infarct. Initial experience with doppler echocardiography

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    Valdir A. Moisés

    2000-08-01

    Full Text Available OBJECTIVE: To assess by Doppler echocardiography the structural and functional alterations of rat heart with surgical induced extensive myocardial infarction. METHODS: Five weeks after surgical ligature of the left coronary artery, 38 Wistar-EPM rats of both sexes, 10 of them with extensive infarction, undergone anatomical and functional evaluation by Doppler echocardiography and then euthanized for anatomopathological analysis. RESULTS: Echocardiography was 100% sensible and specific to anatomopathological confirmed extensive miocardial infarction. Extensive infarction lead to dilatation of left ventricle (diastolic diameter: 0.89cm vs.0.64cm; systolic: 0.72cm vs. 0.33cm and left atrium (0.55cm vs. 0.33cm; thinning of left ventricular anterior wall (systolic: 0.14cm vs. 0.23cm, diastolic: 0.11cm vs. 0.14cm; increased mitral E/ A wave relation (6.45 vs. 1.95. Signals of increased end diastolic ventricle pressure, B point in mitral valve tracing in 62.5% and signs of pulmonary hypertension straightening of pulmonary valve (90% and notching of pulmonary systolic flow (60% were observed in animals with extensive infarction. CONCLUSION: Doppler echocardiography has a high sensitivity and specificity for detection of chronic extensive infarction. Extensive infarction caused dilatation of left cardiac chambers and showed in Doppler signals of increased end diastolic left ventricular pressure and pulmonary artery pressure.

  15. Transthoracic Doppler echocardiography compared with positron emission tomography for assessment of coronary microvascular dysfunction

    DEFF Research Database (Denmark)

    Michelsen, Marie Mide; Mygind, Naja Dam; Pena, Adam

    2017-01-01

    stenosis at invasive coronary angiography, TTDE CFVR by dipyridamole induced stress and MBFR by rubidium-82 PET with adenosine was successfully measured in 107 subjects. Repeatability of TTDE CFVR was assessed in 10 symptomatic women and in 10 healthy individuals. RESULTS: MBFR was systematically higher......BACKGROUND: Coronary microvascular function can be assessed by transthoracic Doppler echocardiography as a coronary flow velocity reserve (TTDE CFVR) and by positron emission tomography as a myocardial blood flow reserve (PET MBFR). PET MBFR is regarded the noninvasive reference standard...... for measuring coronary microvascular function but has limited availability. We compared TTDE CFVR with PET MBFR in women with angina pectoris and no obstructive coronary artery disease and assessed repeatability of TTDE CFVR. METHODS: From a cohort of women with angina and no obstructive coronary artery...

  16. Computer simulation studies of pulsed Doppler signals from vortices

    Institute of Scientific and Technical Information of China (English)

    CHEN Sizhong; WANG Yuanyuan; WANG Weiqi

    2001-01-01

    A computer simulation method for pulsed Doppler signals from vortices was proposed to generate simulated vortex Doppler signals under various given circumstances. The relative waveforms, such as the maximum frequency waveform, the mean frequency waveform and the bandwidth waveform, were obtained using the short time Fourier analysis of those simulated signals. The relations were studied between several spectrum parameters obtained from these waveforms and given simulation conditions, such as the position and the size of the sample volume, the distance between two vortices, the free stream velocity and the maximum tangent velocity of the vortex. The sensitive parameters were found to detect vortices using the pulsed Doppler techniques.

  17. Doppler Ambiguity Resolution Based on Random Sparse Probing Pulses

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    Yunjian Zhang

    2015-01-01

    Full Text Available A novel method for solving Doppler ambiguous problem based on compressed sensing (CS theory is proposed in this paper. A pulse train with the random and sparse transmitting time is transmitted. The received signals after matched filtering can be viewed as randomly sparse sampling from the traditional fixed-pulse repetition frequency (PRF echo signals. The whole target echo could be reconstructed via CS recovery algorithms. Through refining the sensing matrix, which is equivalent to increase the sampling frequency of target characteristic, the Doppler unambiguous range is enlarged. In particular, Complex Approximate Message Passing (CAMP algorithm is developed to estimate the unambiguity Doppler frequency. Cramer-Rao lower bound expressions are derived for the frequency. Numerical simulations validate the effectiveness of the proposed method. Finally, compared with traditional methods, the proposed method only requires transmitting a few sparse probing pulses to achieve a larger Doppler frequency unambiguous range and can also reduce the consumption of the radar time resources.

  18. Impacts of acute severe pulmonary regurgitation on right ventricular geometry and contractility assessed by tissue-Doppler echocardiography

    DEFF Research Database (Denmark)

    Kjaergaard, Jesper; K. Iversen, Kasper; G Vejlstrup, Niels

    2010-01-01

    model. METHODS AND RESULTS: Transthoracic echocardiography, including tissue-Doppler echocardiography for the evaluation of regional longitudinal function, was performed immediately before and after induction of severe PR by deployment of a stent in the pulmonary valve annulus of 32 farm pigs. Acute PR....... No changes in global or regional longitudinal contractility or deformation were observed despite significant changes in the cardiac chamber geometry. An increase in radial shortening may imply that the RV compensates by increasing radial contraction as an adjunct to dilatation....

  19. Avaliação dos fluxos das valvas aórtica e pulmonar com ecocardiografia Doppler pulsátil em cães clinicamente sadios Evaluation of aortic and pulmonary valves flow with pulsed-wave Doppler echocardiography in healthy dogs

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    Lilian C. Petrus

    2010-07-01

    Full Text Available Avaliaram-se com Doppler pulsátil os fluxos das valvas aórtica (AO e pulmonar (Pul por meio de análise qualitativa (presença de regurgitações valvares e características do espectro avaliado e quantitativa, com obtenção de parâmetros ecocardiográficos como velocidades máxima (V. Max. e média (V. Me., integral de velocidade (VTI, tempo de aceleração (TA e ejeção (TE, de 30 cães considerados clinicamente sadios por meio de exames físico, laboratoriais, eletrocardiográfico, ecocardiográfico (modos uni e bidimensional, radiográfico de tórax e mensuração da pressão arterial sistêmica. Obtiveram-se os seguintes resultados para os referidos parâmetros: V.max. AO= 1,22± 19,38m/s; V. Me. AO= 0,72± 0,08m/s; VTI AO= 0,14± 0,02m; TA AO= 38,80± 11,29ms; TE AO= 197,90± 24,77ms; V. Max. Pul= 0,95± 0,18m/s; V. Me. Pul= 0,63± 0,10m/s; VTI Pul= 0,13± 0,02m; TA Pul= 70,97± 18,87ms; TE Pul= 203,70± 28,98ms. Em apenas três animais observou-se regurgitação pulmonar. Alguns parâmetros apresentaram correlação negativa com a variável freqüência cardíaca (VTI AO, TE AO, VTI Pul, TA Pul, TE Pul; outros correlação positiva com a variável peso (VTI AO, TA AO, TE AO, VTI Pul, TE Pul, e não se observou influência da variável sexo na maioria dos parâmetros avaliados. Na comparação entre os dois fluxos, observaram-se V. Max. AO e V. Me. AO maiores que V. Max. Pul. e V. Me. Pul., respectivamente, VTI AO maior que VTI Pul, e TA AO menor que TA Pul.This study evaluated aortic (AO and pulmonary (Pul valves flow with pulsed-wave Doppler by qualitative (presence of valvar insufficiency and characteristic of flow profile and quantitative analysis, and the following echocardiographic parameters were obtained: peak (PV and mean (MV velocities, velocity-time integral (VTI, acceleration (AT and ejection (ET time. Thirty dogs were studied, and to be considered normal, physical, laboratory, electrocardiographic, echocardiographic (uni

  20. Diagnosis of asymptomatic atrial septal aneurysms using two-dimensional color Doppler and contrast transthoracic echocardiography

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Objective To evaluate the dimensions of atrial septal aneurysm (ASA), the presence and characteristics of interatrial shunt, the movement of the wall of the aneurysm, and correlation between these findings and sign and/or symptoms suggesting embolism in Manisa, a district of a western Anatolian city of Turkey. Methods Two thousand five hundred cases were examined by routine transthoracic echocardiography (TTE) in both pediatric and adult cardiology outpatient clinics. ASA was detected in 20 cases and evaluated by two-dimensional color Doppler echocardiography (CDE). The length of the base, the maximum radius and the maximum displacement of ASA were measured. The shunt between the atria was examined by CDE. In cases where a shunt could not be found, galactose and palmitic acid was injected. Standard 12-lead electrocardiogram (ECG) and exercise stress test were also performed. Results No clinical signs or symptoms were found, suggesting a systemic or cerebral embolism. The maximum displacement of ASA was between 2 and 5 mm. All of the aneurysms were localized in the right atrium, and the walls of the aneurysm did not move beyond the base of the left atrium during the maximum displacement. Interatrial shunt was detected in 14 of 20 patients (70%) by CDE and in the remaining six cases by contrast TTE. Frequent ventricular ectopic beats were observed in one patient. Conclusions During routine TTE we observed 0.8% asymptomatic ASA in our population. The use of a contrast agent was found to be a valuable additional method in patients with ASA when the shunt could not be detected by CDE. The risk for embolism is not high when the maximum displacement of the wall of ASA was 5 mm or less and no bulge into the left atrium was observed. Based on our experience with this method, TTE is easy to perform, well-tolerated and acceptable.

  1. The implication of tissue Doppler echocardiography and cardiopulmonary exercise in early detection of cardiac dysfunction in systemic lupus erythematosus patients

    Science.gov (United States)

    Elnady, Basant M.; Abdelghafar, Ayman Saeed Mohamed; Khalik, El Shazly Abdul; Algethami, Mohammed Mesfer; Basiony, A.S.; Al-otaibi, Mona Dhaif Allah; Al-otaibi, Maram Eidhah

    2016-01-01

    Objective Systemic lupus erythematosus (SLE) can present limitations to exercise capacity and quality of life (QoL) because of various clinical conditions, such as pulmonary disease or heart disease. Tissue Doppler echocardiography (TDE) offers the promise of an objective measurement to quantify regional and global ventricular function through the assessment of myocardial velocity data. This study aimed to assess the intensity of left ventricular (LV) and right ventricular (RV) systolic and diastolic dysfunction in SLE patients by means of TDE and cardiopulmonary exercise (CPX) testing to determine their impact on QoL. Material and Methods Overall, 56 SLE patients within two tertiary healthcare centers as well as 50 healthy controls were examined with TDE after the exclusion of cardiovascular risk factors. TDE was performed for maximal systolic (S), early diastolic (E′), and late diastolic (A′) velocities of the mitral and tricuspid annulus. Pulsed wave (PW) Doppler of mitral and tricuspid valve inflow was performed in addition to the estimation of the left ventricle ejection fraction and assessment of right ventricle systolic function by tricuspid annular plane systolic excursion (TAPSE). Disease activity was assessed by the Systemic Lupus Activity Measure (SLAM), and the damage index was assessed by the Systemic Lupus International Collaborating Clinics (SLICC)/American College of Rheumatology (ACR) Damage Index (SDI). CPX tests according to the modified Bruce protocol were performed. Results SLE patients in both subgroups had more or less similar laboratory data and statistically higher values of ESR, CRP, and anticardiolipin (aCL) antibodies compared to the control group. LV function showed statistically insignificant EF compared to the control group, being lower in the patient group. Tissue Doppler image revealed that E′ and A′ of the mitral annulus were lower in the patient group than in the control group. Concerning RV, TAPSE in the patient group was

  2. Rats with high left ventricular end-diastolic pressure can be identified by Doppler echocardiography one week after myocardial infarction

    OpenAIRE

    R.M. Saraiva; Kanashiro-Takeuchi,R.M.; E.L. Antonio; Campos, O; P.J.F. Tucci; Moisés,V.A.

    2007-01-01

    The severity of left ventricular (LV) dysfunction in rats with myocardial infarction (MI) varies widely. Because homogeneity in baseline parameters is essential for experimental investigations, a study was conducted to establish whether Doppler echocardiography (DE) could accurately identify animals with high LV end-diastolic pressure as a marker of LV dysfunction soon after MI. Direct measurements of LV end-diastolic pressure were made and DE was performed simultaneously 1 week after surgica...

  3. The Evaluation of Diastolic Dysfunction with Tissue Doppler Echocardiography in Women with Subclinical Hypothyroidism and the Effect of L-Thyroxine Treatment on Diastolic Dysfunction: A Pilot Study

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    Gulbanu Erkan

    2011-01-01

    Full Text Available Background. Subclinical hypothyroidism (SH predominantly affects women. The necessity of treatment in SH is controversial. Objective. We aimed to investigate the response of diastolic dysfunction to thyroid hormone replacement therapy (THRT in women. Methods and Results. Twenty-two female subjects with SH and 20 euthyroid female controls were enrolled. Baseline and follow-up biochemical, hormonal, and echocardiographic evaluations were performed. Repeat echocardiograms were performed three months after the achievement of a euthyroid status with THRT. Mean baseline myocardial performance index (MPI was 0.27±0.08 in the SH group, and 0.22±0.06 in the control group (P=0.03. MPI did not change significantly after THRT. Pulsed-wave Doppler findings were not different among the groups. However, tissue Doppler-derived mitral annular E’ velocities were significantly lower in the SH group. A moderate but significant improvement was observed in E’ velocities after THRT (13.2±3.87 versus 14.53±2.75, P=0.04. We also observed left ventricular concentric remodeling in SH patients which was reversible with THRT. Conclusions. Tissue Doppler echocardiography may be a useful tool for monitoring the response of diastolic dysfunction to thyroid hormone replacement therapy in patients with SH. Our findings suggest that THRT may reverse diastolic dysfunction in women with SH.

  4. The evaluation of diastolic dysfunction with tissue Doppler echocardiography in women with subclinical hypothyroidism and the effect of L-thyroxine treatment on diastolic dysfunction: a pilot study.

    Science.gov (United States)

    Erkan, Gulbanu; Erkan, Aycan Fahri; Cemri, Mustafa; Karaahmetoglu, Selma; Cesur, Mustafa; Cengel, Atiye

    2011-01-01

    Background. Subclinical hypothyroidism (SH) predominantly affects women. The necessity of treatment in SH is controversial. Objective. We aimed to investigate the response of diastolic dysfunction to thyroid hormone replacement therapy (THRT) in women. Methods and Results. Twenty-two female subjects with SH and 20 euthyroid female controls were enrolled. Baseline and follow-up biochemical, hormonal, and echocardiographic evaluations were performed. Repeat echocardiograms were performed three months after the achievement of a euthyroid status with THRT. Mean baseline myocardial performance index (MPI) was 0.27 ± 0.08 in the SH group, and 0.22 ± 0.06 in the control group (P = 0.03). MPI did not change significantly after THRT. Pulsed-wave Doppler findings were not different among the groups. However, tissue Doppler-derived mitral annular E' velocities were significantly lower in the SH group. A moderate but significant improvement was observed in E' velocities after THRT (13.2 ± 3.87 versus 14.53 ± 2.75, P = 0.04). We also observed left ventricular concentric remodeling in SH patients which was reversible with THRT. Conclusions. Tissue Doppler echocardiography may be a useful tool for monitoring the response of diastolic dysfunction to thyroid hormone replacement therapy in patients with SH. Our findings suggest that THRT may reverse diastolic dysfunction in women with SH.

  5. Can transthoracic Doppler echocardiography be used to detect coronary slow flow phenomenon?

    Institute of Scientific and Technical Information of China (English)

    NIE Shao-ping; LUO Tai-yang; DONG Jian-zeng; LIU Xiao-hui; MA Chang-sheng; GENG Li-li; WANG Xiao; ZHANG Xiao-shan; YANG Ya; LIU Bai-qiu; LI Jun; QIAO Yan; LIU Xin-min

    2010-01-01

    Background Coronary slow flow phenomenon (CSFP) is an important, angiographic clinical entity but is lacking non-invasive detecting techniques. This study aimed to elucidate the value of transthoracic Doppler echocardiography (TTDE) in the diagnosis and monitoring of coronary slow flow in left anterior descending (LAD) coronary artery.Methods We consecutively enrolled 27 patients with CSFP in LAD detected by coronary arteriography from August 2009 to April 2010. Thirty-eight patients with angiographically normal coronary flow served as control. Corrected thrombolysis in myocardial infarction (TIMI) frame count (CTFC) was used to document coronary flow velocities. All subjects underwent TTDE within 24 hours after coronary angiography. LAD flow was detected and the coronary diastolic peak velocities (DPV) and diastolic mean velocities (DMV) were calculated.Results Sixty of 65 (92.3%) subjects successfully underwent TTDE. Baseline clinical characteristics were similar between the two groups. Coronary DPV and DMV of LAD were significantly lower in the CSFP group than in the control group ((0.228±0.029) m/s vs. (0.302±0.065) m/s, P=0.000; (0.176±0.028) m/s vs. (0.226±0.052) m/s, P=0.000,respectively). There was a high inverse correlation between CTFC and coronary DPV and DMV (r=-0.727, P=0.000;r=-0.671, P=0.000, respectively). Receiver operating characteristic (ROC) curve showed that the area under the curve (AUC) was less than one half for coronary DPV (AUC=0.104) and DMV (AUC=0.204), respectively.Conclusions In patients with CSFP, there is a high inverse correlation between CTFC and coronary diastolic flow velocities in the LAD coronary artery, as measured by TTDE. The value of TTDE in the monitoring and evaluation of coronary flow in patients with CSFP deserves further investigation.

  6. Preliminary correlation study of regional ventricular long-axis velocity and adjacent intraventricular flow velocity in normal cases using dual-pulse wave Doppler echocardiography%双脉冲波多普勒超声评价舒张期左心室节段心肌运动及其邻近心室腔内同步血流的耦合情况

    Institute of Scientific and Technical Information of China (English)

    沈玉萍; 尹立雪; 程重庆; 张丽娟

    2013-01-01

    Objective To investigate regional ventricular long-axis velocity and adjacent intraventricular flow velocity using dual-pulse wave(PW) Doppler echocardiography synchronously,and to analyze the coupling relationship between regional ventricular long-axis strain and adjacent intraventricular pressure gradients in normal cases using dual-PW Doppler echocardiography.Methods Eighty-six normal subjects aged 19~66 years [mean age (37.49 ± 11.97)years] underwent routine echocardiography and dualPW Doppler echocardiographic exam.Total 18 segments were sampled using dual-PW Doppler (PW/TDI mode) images at basal,mid and apical levels on three standard apical views,and electrocardiogram was recorded simultaneously.Peak early diastolic velocity (emax),peak late diastolic velocity (amax),peak early mitral diastolic inflow velocity (Emax),regional peak early diastolic velocity (Em),regional peak late diastolic velocity (Am) and regional peak early diastolic inflow velocity (E) were measured simultaneously in the same one cardiac cycle.Myocardial variations of left ventricular segments were observed.Em,Am and E of different levels from different ventricular wall were analyzed.The co-relationship between regional ventricular long-axis strain and adjacent intraventricular pressure gradients were calculated and analyzed.Results ①Regional myocardial velocity and regional peak early diastolic inflow velocity in normal subjects declined from basal to apical segments gradually at the same ventricular wall (P < 0.01).② Emax was correlated with emax(r =0.418,P <0.001),and E was correlated with Em (posterior septum,r =0.610,P <0.001 ;anterior wall,r =0.499,P <0.001).③There was a medium correlation between normal longaxis strain in segments and adjacent intraventricular pressure gradients (the global,r =0.412,P <0.001 ;posterior septum,r =0.319,P <0.005).Conclusions The acquirement of E and Em by dual-PW Doppler showed downtrend of segmental wall movement and

  7. Validation of the severity index by cardiac catheterization and Doppler echocardiography in patients with aortic sclerosis and stenosis

    Directory of Open Access Journals (Sweden)

    Rosales Joseph

    2006-03-01

    Full Text Available Abstract The severity index is a new echocardiographic measure that is thought to be an accurate indicator of aortic leaflet pathology in patients with AS. However, it has not been validated against cardiac catheterization or Doppler echocardiographic measures of AS severity nor has it been applied to patients with aortic sclerosis. The purposes of this study were to compare the severity index to invasive hemodynamics and Doppler echocardiography across the spectrum of calcific aortic valve disease, including aortic sclerosis and AS. 48 patients with aortic sclerosis and AS undergoing echocardiography and cardiac catheterization comprised the study population. The aortic valve leaflets were assessed for mobility (scale 1 to 6 and calcification (scale 1 to 4 and the severity index was calculated as the sum of the mobility and calcification scores according to the methods of Bahler et al. The severity index increased with increasing severity of aortic valve disease; the severity indices for patients with aortic sclerosis, mild to moderate AS and severe AS were 3.38 ± 1.06, 6.45 ± 2.16 and 8.38 ± 1.41, respectively. The aortic jet velocity by echocardiography and the square root of the maximum aortic valve gradient by cardiac catheterization correlated well with the severity index (r = 0.84, p

  8. Relevance of tissue Doppler in the quantification of stress echocardiography for the detection of myocardial ischemia in clinical practice

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    Sicari Rosa

    2005-01-01

    Full Text Available Abstract In the present article we review the main published data on the application of Tissue Doppler Imaging (TDI to stress echocardiography for the detection of myocardial ischemia. TDI has been applied to stress echocardiography in order to overcome the limitations of visual analysis for myocardial ischemia. The introduction of a new technology for clinical routine use should pass through the different phases of scientific assessment from feasibility studies to large multicenter studies, from efficacy to effectiveness studies. Nonetheless the pro-technology bias plays a major role in medicine and expensive and sophisticated techniques are accepted before their real usefulness and incremental value to the available ones is assessed. Apparently, TDI is not exempted by this approach : its applications are not substantiated by strong and sound results. Nonetheless, conventional stress echocardiography for myocardial ischemia detection is heavily criticized on the basis of its subjectivity. Stress echocardiography has a long lasting history and the evidence collected over 20 years positioned it as an established tool for the detection and prognostication of coronary artery disease. The quantitative assessment of myocardial ischemia remains a scientific challenge and a clinical goal but time has not come for these newer ultrasonographic techniques which should be restricted to research laboratories.

  9. HPRF pulse Doppler stepped frequency radar

    Institute of Scientific and Technical Information of China (English)

    LONG Teng; REN LiXiang

    2009-01-01

    Stepped frequency radar Is a well known scheme to generate high range resolution profile (HRRP) of targets. Through appropriate radar parameter design, the radar enables both unambiguous velocity measurement and high resolution ranging within a single dwell in a high pulse repetition frequency (HPRF) mode. This paper analyzes in detail the design principle of the HPRF stepped frequency radar system, the solution to its ambiguity issue, as well as its signal processing method. Both theoretical analysis and simulation results demonstrate that the proposed radar scheme can work independently to solve the problem of motion compensation, and is therefore highly applicable to many new types of radar.

  10. Incoherent pulse Doppler lidar as the velocimeter system

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This note reports a new type of incoherent pulse laser Doppler lidar velocimeter with iodine molecular filter as a frequency discriminator. Its transmitter subsystem applies a Nd:YAG pulse laser which is injected with a single longitudinal-mode diode pumped continuous seeder laser.The field experiment proved that this velocimeter measurement results are consistent with those measured by photoelectric velocimeter. Measurements of eight different velocities show that the standard deviation is 0.56 m/s, the range resolution is 3.75 m.

  11. Noninvasive monitoring of myocardial function after surgical and cytostatic therapy in a peritoneal metastasis rat model: assessment with tissue Doppler and non-Doppler 2D strain echocardiography

    Directory of Open Access Journals (Sweden)

    Wernecke Klaus-Dieter

    2007-07-01

    Full Text Available Abstract Objective We sought to evaluate the impact of different antineoplastic treatment methods on systolic and diastolic myocardial function, and the feasibility estimation of regional deformation parameters with non-Doppler 2D echocardiography in rats. Background The optimal method for quantitative assessment of global and regional ventricular function in rats and the impact of complex oncological multimodal therapy on left- and right-ventricular function in rats remains unclear. Methods 90 rats after subperitoneal implantation of syngenetic colonic carcinoma cells underwent different onclogical treatment methods and were diveded into one control group and five treatment groups (with 15 rats in each group: group 1 = control group (without operation and without medication, group 2 = operation group without additional therapy, group 3 = combination of operation and photodynamic therapy, group 4 = operation in combination with hyperthermic intraoperative peritoneal chemotherapy with mitomycine, and group 5 = operation in combination with hyperthermic intraoperative peritoneal chemotherapy with gemcitabine, group 6 = operation in combination with taurolidin i.p. instillation. Echocardiographic examination with estimation of wall thickness, diameters, left ventricular fractional shortening, ejection fraction, early and late diastolic transmitral and myocardial velocities, radial and circumferential strain were performed 3–4 days after therapy. Results There was an increase of LVEDD and LVESD in all groups after the follow-up period (P = 0.0037. Other LV dimensions, FS and EF as well as diastolic mitral filling parameters measured by echocardiography were not significantly affected by the different treatments. Values for right ventricular dimensions and function remained unchanged, whereas circumferential 2D strain of the inferior wall was slightly, but significantly reduced under the treatment (-18.1 ± 2.5 before and -16.2 ± 2.9 % after

  12. Relativistic Doppler effect: universal spectra and zeptosecond pulses.

    Science.gov (United States)

    Gordienko, S; Pukhov, A; Shorokhov, O; Baeva, T

    2004-09-10

    We report on a numerical observation of the train of zeptosecond pulses produced by the reflection of a relativistically intense femtosecond laser pulse from the oscillating boundary of an overdense plasma because of the Doppler effect. These pulses promise to become unique experimental and technological tools since their length is of the order of the Bohr radius and the intensity is extremely high proportional, variant 10(19) W/cm(2). We present the physical mechanism, analytical theory, and direct particle-in-cell simulations. We show that the harmonic spectrum is universal: the intensity of nth harmonic scales as 1/n(p) for n<4gamma(2), where gamma is the largest gamma factor of the electron fluid boundary, and p=3 and p=5/2 for the broadband and quasimonochromatic laser pulses, respectively.

  13. Multipath-dominant, pulsed doppler analysis of rotating blades

    CERN Document Server

    Robinson, Michael

    2012-01-01

    We present a novel angular fingerprinting algorithm for detecting changes in the direction of rotation of a target with a monostatic, stationary sonar platform. Unlike other approaches, we assume that the target's centroid is stationary, and exploit doppler multipath signals to resolve the otherwise unavoidable ambiguities that arise. Since the algorithm is based on an underlying differential topological theory, it is highly robust to distortions in the collected data. We demonstrate performance of this algorithm experimentally, by exhibiting a pulsed doppler sonar collection system that runs on a smartphone. The performance of this system is sufficiently good to both detect changes in target rotation direction using angular fingerprints, and also to form high-resolution inverse synthetic aperature images of the target.

  14. Limitations of Doppler echocardiography for the post-operative evaluation of aortic coarctation

    NARCIS (Netherlands)

    De Mey, S; Segers, P; Coomans, [No Value; Verhaaren, H; Verdonck, P

    2001-01-01

    Doppler blood Row measurements and derived pressure differences. through the Bernoulli equation. are used in the diagnosis of aortic coarctation, a congenital stenosis distal to the Left subclavian artery. Doppler velocities remain elevated at the coarctation site after successful repair of coarctat

  15. Pulsed-wave Doppler ultrasonographic evaluation of hepatic vein in dogs with tricuspid regurgitation

    Science.gov (United States)

    Kim, Jaehwan; Kim, Soyoung

    2017-01-01

    This study was performed to identify the relationships between hepatic vein (HV) measurements, including flow velocity and waveform, using pulsed-wave (PW) Doppler ultrasonography, and the severity of tricuspid regurgitation (TR) in dogs. The study included 22 dogs with TR and 7 healthy dogs. The TR group was subdivided into 3 groups according to TR jet profile obtained by echocardiography. The hepatic venous waveform was obtained and classified into 3 types. A variety of HV measurements, including the maximal velocities of the atrial systolic, systolic (S), end ventricular systolic, and diastolic (D) waves and the ratio of the S- and D- wave velocities (S/D ratio), were acquired. TR severity was significantly correlated with the S- (r = −0.380, p = 0.042) and D- (r = 0.468, p = 0.011) wave velocities and the S/D ratio (r = −0.747, p < 0.001). Receiver operating characteristic curve analysis revealed the highest sensitivity and specificity for the S/D ratio (89% and 75%, respectively) at a threshold of 0.97 with excellent accuracy (AUC = 0.911, p < 0.001). In conclusion, PW Doppler ultrasonography of the HV can be used to identify the presence of significant TR and to classify TR severity in dogs. PMID:27515264

  16. Tissue Doppler echocardiography and biventricular pacing in heart failure: Patient selection, procedural guidance, follow-up, quantification of success

    Directory of Open Access Journals (Sweden)

    Baumann Gert

    2004-09-01

    Full Text Available Abstract Asynchronous myocardial contraction in heart failure is associated with poor prognosis. Resynchronization can be achieved by biventricular pacing (BVP, which leads to clinical improvement and reverse remodeling. However, there is a substantial subset of patients with wide QRS complexes in the electrocardiogram that does not improve despite BVP. QRS width does not predict benefit of BVP and only correlates weakly with echocardiographically determined myocardial asynchrony. Determination of asynchrony by Tissue Doppler echocardiography seems to be the best predictor for improvement after BVP, although no consensus on the optimal method to assess asynchrony has been achieved yet. Our own preliminary results show the usefulness of Tissue Doppler Imaging and Tissue Synchronization Imaging to document acute and sustained improvement after BVP. To date, all studies evaluating Tissue Doppler in BVP were performed retrospectively and no prospective studies with patient selection for BVP according to echocardiographic criteria of asynchrony were published yet. We believe that these new echocardiographic tools will help to prospectively select patients for BVP, help to guide implantation and to optimize device programming.

  17. Pulsed photoacoustic Doppler flow measurements in blood-mimicking phantoms

    Science.gov (United States)

    Brunker, J.; Beard, P.

    2011-03-01

    The feasibility of making spatially resolved measurements of blood flow using pulsed photoacoustic Doppler techniques has been explored. Doppler time shifts were quantified via cross-correlation of pairs of photoacoustic waveforms generated within a blood-simulating phantom using pairs of laser light pulses. The photoacoustic waves were detected using a focussed or planar PZT ultrasound transducer. For each flow measurement, a series of 100 waveform pairs was collected. Previous data processing methods involved rejection of poorly correlated waveform pairs; the modal velocity value and standard deviation were then extracted from the selected distribution of velocity measurements. However, the data selection criteria used in this approach is to some extent arbitrary. A new data analysis protocol, which involves averaging the 100 cross-correlation functions and thus uses all of the measured data, has been designed in order to prevent exclusion of outliers. This more rigorous approach has proved effective for quantifying the linear motion of micron-scale absorbers imprinted on an acetate sheet moving with velocities in the range 0.14 to 1.25 ms-1. Experimental parameters, such as the time separation between the laser pulses and the transducer frequency response, were evaluated in terms of their effect on the accuracy, resolution and range of measurable velocities. The technique was subsequently applied to fluid phantoms flowing at rates less than 5 mms-1 along an optically transparent tube. Preliminary results are described for three different suspensions of phenolic resin microspheres, and also for whole blood. Velocity information was obtained even under non-optimal conditions using a low frequency transducer and a low pulse repetition frequency. The distinguishing advantage of pulsed rather than continuous-wave excitation is that spatially resolved velocity measurements can be made. This offers the prospect of mapping flow within the microcirculation and thus

  18. Range ambiguity resolution for high PRF pulse-Doppler radar

    Science.gov (United States)

    Postema, G. B.

    The range ambiguity resolution for high 'PRF pulse-Doppler radars can be resolved using a simple algorithm based on residue arithmetic. The unambiguous range is found from R = T + R(a), where T is the output of a look-up table and R(a) is one of the measured ambiguous ranges. This formula is easily extended to multiple PRF ranging systems, where three or more measurements are required for the ambiguity resolution. Target obscuration in clutter reduces the visibility and leads, especially in dense target environments, to ghost ranges. It is shown that long range coverage requires a small resolved pulse length and PRFs as low as practical in the intended clutter and target environment. Special attention is given to the generation of sparsely populated look-up tables that reduce the ghosting problem. A practical example for an S-band surveillance radar is presented.

  19. Tissue Doppler echocardiography in persons with hypertension, diabetes, or ischaemic heart disease: the Copenhagen City Heart Study

    DEFF Research Database (Denmark)

    Mogelvang, Rasmus; Sogaard, Peter; Pedersen, Sune A

    2009-01-01

    AIMS: To test the hypothesis that echocardiographic tissue Doppler imaging (TDI) reveals reduced myocardial function in hypertension, diabetes, and ischaemic heart disease (IHD) in the general population. METHODS AND RESULTS: Within a large, community-based population study, cardiac function...... and diastolic cardiac function in hypertension [n = 345; LD 10.1 (+/-standard deviation, SD 2.0 mm), P diabetes [n = 65; LD 9.8 (+/-SD 2.2 mm), P ....001] compared with controls [n = 533; LD 11.4 (+/-SD 2.0 mm); E/e' 9.0 (x/SD 1.3)]. This pattern remained significant after adjusting for age, sex, body mass index, heart rate, and the results of conventional echocardiography. CONCLUSION: In the general population, persons with hypertension, diabetes, or IHD...

  20. Assessment of left ventricular functions with tissue Doppler, strain, and strain rate echocardiography in patients with familial Mediterranean fever.

    Science.gov (United States)

    Ceylan, Özben; Özgür, Senem; Örün, Utku Arman; Doğan, Vehbi; Yılmaz, Osman; Keskin, Mahmut; Arı, Mehmet Emre; Erdoğan, Özlem; Karademir, Selmin

    2015-08-01

    This study assessed the early changes in regional and global systolic and diastolic myocardial functions in patients with familial Mediterranean fever without any cardiovascular symptoms using tissue Doppler and strain and strain rate echocardiography and compared them to the results of a control group. This study has a cross-sectional and observational design. FMF patients with normal left ventricular function were included in the study. We excluded patients who had arrhythmia, acquired/congenital heart disease, pericarditis, or acute attack. We compared 45 children with familial Mediterranean fever on colchicine therapy and 45 age- and sex-matched healthy children. The 45 patients with familial Mediterranean fever included 24 (55.3%) girls and 21 (46.7%) boys with a mean age of 11.3 ± 3.7 (range 2-18) years. The mean disease duration was 4.6 ± 2.4 (range 0.5-10) years. In the patient group, the homozygous M694V mutation was the most common (64.4%) mutation. The patients with familial Mediterranean fever had statistically lower longitudinal global strain, radial global strain, and strain rates (-14.44 ± 4.77%, 14.80 ± 6.29%, and 0.59 ± 0.24 s, respectively) than the controls (-17.40 ± 1.79%, 17.53 ± 4.63%, and 0.83 ± 0.51 s) (p familial Mediterranean fever who are subclinical from a cardiac aspect might have normal left ventricular function as measured by conventional echocardiography. However, the disease affects their myocardial tissue, and these patients should be followed with conventional, strain, and strain rate echocardiography techniques regularly.

  1. Ratio of left ventricular peak E-wave velocity to flow propagation velocity assessed by color M-mode Doppler echocardiography in first myocardial infarction

    DEFF Research Database (Denmark)

    Møller, J E; Søndergaard, E; Seward, J B;

    2000-01-01

    OBJECTIVES: To determine the ability of the ratio of peak E-wave velocity to flow propagation velocity (E/Vp) measured with color M-mode Doppler echocardiography to predict in-hospital heart failure and cardiac mortality in an unselected consecutive population with first myocardial infarction (MI......). BACKGROUND: Several experimental studies indicate color M-mode echocardiography to be a valuable tool in the evaluation of diastolic function, but data regarding the clinical value are lacking. METHODS: Echocardiography was performed within 24 h of arrival at the coronary care unit in 110 consecutive...... or =1.5 measured with color M-mode echocardiography is a strong predictor of in-hospital heart failure. Furthermore, E/Vp is superior to systolic measurements in predicting 35 day survival although Dt

  2. Angiographically borderline left main coronary artery lesions: correlation of transthoracic doppler echocardiography and intravascular ultrasound: a pilot study

    Directory of Open Access Journals (Sweden)

    Varga Albert

    2011-06-01

    Full Text Available Abstract Background the clinical decision making could be difficult in patients with borderline lesions (visually assessed stenosis severity of 30 to 50% of the left main coronary artery (LM. The aim of the study was to evaluate the relationship between transthoracic Doppler (TTDE peak diastolic flow velocity (PDV and intravascular ultrasound (IVUS measurements in the assessment of angiographically borderline LM lesions. Methods 27 patients (mean age 64 ± 8 years, 21 males with borderline LM stenosis referred for IVUS examination were included in the study. We performed standard IVUS with minimal lumen area (MLA and plaque burden (PB measurement and routine quantitative coronary angiography (QCA with diameter stenosis (%DS and area stenosis (%AS assessment in all. During TTDE, resting PDV was measured in the LM. Results interpretable Doppler signal could be obtained in 24 patients (88% feasibility; therefore these patients entered the final analysis. MLA was 7.1 ± 2.7 mm2. TTDE measured PDV correlated significantly with IVUS-derived MLA (r = -0.46, p 2 LM stenosis. Conclusion In angiographically borderline LM disease, resting PDV from transthoracic echocardiography is increased in presence of increased plaque burden by IVUS. TTDE evaluation might be a useful adjunct to other invasive and non-invasive methods in the assessment of borderline LM lesions. Further, large scale studies are needed to establish the exact cut-off value of PDV for routine clinical application.

  3. Predicting Paroxysmal Atrial Fibrillation in Cerebrovascular Ischemia Using Tissue Doppler Imaging and Speckle Tracking Echocardiography

    DEFF Research Database (Denmark)

    Olsen, Flemming Javier; Jørgensen, Peter Godsk; Møgelvang, Rasmus

    2016-01-01

    , tissue Doppler imaging (TDI), and speckle tracking. TDI was performed to acquire myocardial peak velocities during systole/ventricular contraction (global s'), early diastole/ventricular filling (global e'), and late diastole/atrial contraction (global a'). Speckle tracking was performed for myocardial...

  4. Tissue Doppler echocardiography reveals impaired cardiac function in patients with reversible ischaemia

    DEFF Research Database (Denmark)

    Hoffmann, Søren; Mogelvang, Rasmus; Sogaard, Peter

    2011-01-01

    AIMS: To determine if echocardiographic tissue Doppler imaging (TDI) performed at rest detects reduced myocardial function in patients with reversible ischaemia. METHODS AND RESULTS: Eighty-four patients with angina pectoris, no previous history of ischaemic heart disease and normal left ventricu......AIMS: To determine if echocardiographic tissue Doppler imaging (TDI) performed at rest detects reduced myocardial function in patients with reversible ischaemia. METHODS AND RESULTS: Eighty-four patients with angina pectoris, no previous history of ischaemic heart disease and normal left...... velocities could be demonstrated in patients with a false-positive SPECT compared with controls. CONCLUSION: In patients with stable angina pectoris, preserved ejection fraction, and reversible ischaemia assessed by SPECT, echocardiographic colour TDI performed at rest reveals impaired cardiac function...

  5. All-fiber pulse coherent Doppler LIDAR and its validations

    Science.gov (United States)

    Bu, Lingbing; Qiu, Zujing; Gao, Haiyang; Zhu, Xiaopeng; Liu, Jiqiao

    2015-12-01

    An all-fiber pulsed coherent Doppler LIDAR (CDL) system is described. It uses a fiber laser as a light source at a 1.54-μm wavelength, producing 200 μJ pulses at 10 kHz. The local oscillator signal is mixed with the backscattered light (of different frequency) in the fiber. The atmospheric wind speed is determined through the fast Fourier transform applied to the difference frequency signal acquired by an analog-to-digital converter card. This system was used to measure the atmospheric wind above the upper-air meteorological observatory in Rongcheng (37.10°N, 122.25°E) of China between January 7 and 19, 2015. The CDL data are compared with sounding- and pilot-balloon measurements to assess the CDL performance. The results show that the correlation coefficient of the different wind-speed measurements is 0.93 and their discrepancy 0.64 m/s; the correlation coefficient for wind-direction values is 0.92 and their discrepancy 5.8 deg. A time serial of the wind field, which benefits the understanding of atmospheric dynamics, is presented after the comparisons between data from CDL and balloons. The CDL system has a compact structure and demonstrates good stability, reliability, and a potential for application to wind-field measurements in the atmospheric boundary layer.

  6. Tissue Doppler echocardiography predicts acute myocardial infarction, heart failure, and cardiovascular death in the general population

    DEFF Research Database (Denmark)

    Mogelvang, Rasmus; Biering-Sørensen, Tor; Jensen, Jan Skov

    2015-01-01

    AIMS: To improve risk prediction of cardiovascular morbidity and mortality, we need sensitive markers of cardiac dysfunction; Echocardiographic Tissue Doppler Imaging (TDI) is feasible and harmless and may be ideal for this purpose. METHODS AND RESULTS: Within the community-based Copenhagen City...... by TDI was associated with increased risk of the combined end point, even in the subgroup of persons with a normal conventional echocardiographic examination [per 1 cm/s decrease: s': HR 1.32 (1.12-1.57), P ... in persons with a normal conventional echocardiographic examination....

  7. Cardiac time intervals by tissue Doppler imaging M-mode echocardiography

    DEFF Research Database (Denmark)

    Biering-Sørensen, Tor

    2016-01-01

    BACKGROUND: The preservation of normal cardiac time intervals is intimately related to normal cardiac physiology and function. In the ailing myocardium, the cardiac time intervals will change during disease progression. As left ventricular (LV) systolic function deteriorates, the time it takes...... of whether the LV is suffering from impaired systolic or diastolic function. A novel method of evaluating the cardiac time intervals has recently evolved. Using tissue Doppler imaging (TDI) M-mode through the mitral valve (MV) to estimate the cardiac time intervals may be an improved method reflecting global...

  8. Comparison between cardiovascular magnetic resonance and transthoracic doppler echocardiography for the estimation of effective orifice area in aortic stenosis

    Directory of Open Access Journals (Sweden)

    Larose Eric

    2011-04-01

    Full Text Available Abstract Background The effective orifice area (EOA estimated by transthoracic Doppler echocardiography (TTE via the continuity equation is commonly used to determine the severity of aortic stenosis (AS. However, there are often discrepancies between TTE-derived EOA and invasive indices of stenosis, thus raising uncertainty about actual definite severity. Cardiovascular magnetic resonance (CMR has emerged as an alternative method for non-invasive estimation of valve EOA. The objective of this study was to assess the concordance between TTE and CMR for the estimation of valve EOA. Methods and results 31 patients with mild to severe AS (EOA range: 0.72 to 1.73 cm2 and seven (7 healthy control subjects with normal transvalvular flow rate underwent TTE and velocity-encoded CMR. Valve EOA was calculated by the continuity equation. CMR revealed that the left ventricular outflow tract (LVOT cross-section is typically oval and not circular. As a consequence, TTE underestimated the LVOT cross-sectional area (ALVOT, 3.84 ± 0.80 cm2 compared to CMR (4.78 ± 1.05 cm2. On the other hand, TTE overestimated the LVOT velocity-time integral (VTILVOT: 21 ± 4 vs. 15 ± 4 cm. Good concordance was observed between TTE and CMR for estimation of aortic jet VTI (61 ± 22 vs. 57 ± 20 cm. Overall, there was a good correlation and concordance between TTE-derived and CMR-derived EOAs (1.53 ± 0.67 vs. 1.59 ± 0.73 cm2, r = 0.92, bias = 0.06 ± 0.29 cm2. The intra- and inter- observer variability of TTE-derived EOA was 5 ± 5% and 9 ± 5%, respectively, compared to 2 ± 1% and 7 ± 5% for CMR-derived EOA. Conclusion Underestimation of ALVOT by TTE is compensated by overestimation of VTILVOT, thereby resulting in a good concordance between TTE and CMR for estimation of aortic valve EOA. CMR was associated with less intra- and inter- observer measurement variability compared to TTE. CMR provides a non-invasive and reliable alternative to Doppler-echocardiography for the

  9. Comparison between Doppler echocardiography and hot-film anemometry in measuring the turbulent shear stress downstream of artificial mitral valves: a methodological study

    Institute of Scientific and Technical Information of China (English)

    SUN Yi; LI Rui-jie; LI Gan-niu; LI Bin; WANG Yu; MA Run-wei; YANG Bai-hui

    2013-01-01

    Background Turbulent shear stress (TSS) plays an important role in the research of fluid dynamics of heart valves.This study aimed to perform a quantitative study of TSS downstream of porcine artificial mitral valves in order to verify the correlation of hot-film anemometry (HFA) and Doppler echocardiography combined with computer-aided image analysis for the detection of TSS.Methods A porcine model of mitral valve replacement was established.HFA and Doppler ultrasound techniques were used to directly and indirectly measure TSS-relevant parameters of the artificial mitral valve following different mitral valve replacements:different approaches were used to reserve the subvalvular apparatus of the mitral valve.A correlation analysis was then carried out.Results There was a significant correlation between the HFA and Doppler ultrasound combined with computer-aided image analysis of the TSS at the same time and at the same site.No significant difference was found in the TSS measured by the two methods.Conclusions Compared with HFA,Doppler echocardiography combined with computer-aided image analysis is a safe,non-invasive,and real-time method that enables accurate and quantitative detection of TSS downstream in vivo,objectively reflecting the flow field downstream of the artificial mitral valve.Doppler ultrasound combined with computeraided image analysis can be employed for quantitatively evaluating the downstream hemodynamic performance of the mitral valve.

  10. Assessment of Coronary Flow Velocity Reserve by Noninvasive Transthoracic Doppler Echocardiography in Patients with Angiographically Normal Coronary Arteries

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The measurement of coronary flow velocity reserve (CFVR) by transthoracic Doppler echocardiography (TTDE) with invasive intracoronary Doppler flow wire technique (ICD) was validated and the pathologicalfactors which influence CFVR in patients with angiographically normal coronary arteries were analyzed. CFVR was determined successfully in left anterior descending artery (LAD) in 37 of 40 patients with angiographically normal coronary arteries (men 22, women 15, age 20-75 years, mean age 54 ± 12 years). Coronary flow velocity was measured in the distal LAD by TTDE with contrast enhancement at baseline and during intravenous adenosine infusion of 140 μg/kg per min within 48 h after ICD technique. Average peak velocity at baseline (APVb), average peak velocity during hyperemia (APVh) and CFVR determined from TTDE were correlated closely with those from ICD measurements (APVb: y=0. 64x+5. 04, r=0. 86, P<0. 001;APVh: y=0.63x+14.36, r=0.82, P<0.001; CFVR: y=0.65x+0.92, r=0.88, P<0. 001).For CFVR measurements, the mean differences between TTDE and ICD methods were 0. 12 ±0.39. CFVR in patients with history of hypertension was significantly lower than that in patients without history of hypertension (P<0.05). Intravascular ultrasound (IVUS) was performed in 34patients. Plaque formation was found in LAD by IVUS in 17 (50 %) patients. No significant difference in CFVR was found between the patients without plaque formation (3. 11±0. 49) and those with plaque formation (2. 76±0.53, P=0. 056). It is suggested that TTDE with contrast enhancement provides reliable measurement of APV and CFVR in the distal LAD. The early stage of atherosclerosis could be detected by IVUS, which may be normal in angiography. CFVR is impaired in patients with history of hypertension compared with that in patients without history of hypertension.

  11. Effects of chronic severe pulmonary regurgitation and percutaneous valve repair on right ventricular geometry and contractility assessed by tissue Doppler echocardiography

    DEFF Research Database (Denmark)

    Kjaergaard, Jesper; K. Iversen, Kasper; G Vejlstrup, Niels;

    2010-01-01

    replacement (PPVR) was performed. Tissue Doppler derived measures of global and regional myocardial contractility were obtained by transthoracic echocardiography, and compared to a sham-operated control group (N = 9).RESULTS: Free PR is associated with RV dilatation (RV end-diastolic area increased from 15...... ± 3 to 23 ± 7 cm(2) /m(2) , P strain, and strain rate were unchanged after free PR and after PPVR. No consistent relation...

  12. Range-gated pulsed Doppler ultrasonographic evaluation of carotid arterial blood flow in small preterm infants with patent ductus arteriosus.

    Science.gov (United States)

    Wilcox, W D; Carrigan, T A; Dooley, K J; Giddens, D P; Dykes, F D; Lazzara, A; Ray, J L; Ahmann, P A

    1983-02-01

    Range-gated pulsed Doppler (RGPD) ultrasonography was utilized to study the effect of a patent ductus arteriosus (PDA) on carotid arterial blood flow in small preterm infants. Carotid arterial flow velocity studies were performed on 23 preterm infants, sampling right and left carotid arteries. Studies on seven infants after PDA ligation and on seven who developed no evidence of PDA were used as controls. A strong relationship was demonstrated between diastolic reversal in the carotid arteries and PDA. The results of this study indicate that the RGPD flow velocity curve from the carotid artery is more sensitive than M-mode echocardiography or clinical examination in detecting PDA, and that PDA in small preterm infants is associated with a distinct abnormality in the carotid arterial flow pattern.

  13. Solid breast neoplasms: Differential diagnosis with pulsed Doppler ultrasound

    NARCIS (Netherlands)

    T.J.A. Kuijpers (T. J A); A.I.M. Obdeijn (Inge-Marie); Ph.M. Kruyt (Philip); M. Oudkerk (Matthijs)

    1994-01-01

    textabstractIn this prospective study, duplex Doppler ultrasound was used in 95 consecutive patients with solid breast masses to evaluate the presence of neovascular flow. A positive Doppler signal, i.e., a Doppler shift frequency of more than 1 kHz using a 5 MHz insonating frequency, was found in 3

  14. Tissue Doppler echocardiography improves the diagnosis of coronary artery stenosis in stable angina pectoris

    DEFF Research Database (Denmark)

    Hoffmann, Soren; Jensen, Jan Skov; Iversen, Allan Zeeberg

    2012-01-01

    by colour TDI at six mitral annular sites and averaged to provide global estimates. Duke score (DS), including ST depression, chest pain, and exercise capacity, was used as the outcome of the exercise ECG. Patients with an area stenosis of ≥70% in at least one epicardial coronary artery were categorized......Aim To determine if colour tissue Doppler imaging (TDI) performed at rest in patients with suspected stable angina pectoris (SAP) is able to predict the presence of significant coronary artery disease (CAD). METHODS AND RESULTS: This study comprises 296 consecutive patients with clinically...... suspected SAP, no previous cardiac history, and a normal ejection fraction. All patients were examined by colour TDI, exercise electrocardiogram (ECG), and coronary angiography (CAG). Regional longitudinal systolic (s'), early diastolic (e'), and late diastolic (a') myocardial velocities were measured...

  15. Pulse-Shape Control in an All Fiber Multi-Wavelength Doppler Lidar

    Directory of Open Access Journals (Sweden)

    Töws Albert

    2016-01-01

    Full Text Available Pulse distortion during amplification in fiber amplifiers due to gain saturation and cross talk in a multi-wavelength Doppler lidar are discussed. We present a feedback control technique which is capable of adjusting any predefined pulse shape and show some examples of feedback controlled pulse shapes.

  16. The use of pulsed-wave Doppler in prenatal diagnosis. An update

    OpenAIRE

    DEGANI, S.

    2007-01-01

    Pulsed wave Doppler ultrasound of fetal vessels confirms the similarity of human fetal circulation to the experimental animal physiology, The result of a multitude of research articles in this field is the clinical use of various components of fetal circulation in perinatal medicine. Umbilical, uterine and fetal cerebral arteries as well as the fetal venous circulation show the potential of Doppler ultrasonography.

  17. Application of Echocardiography on Transgenic Mice with Cardiomyopathies

    Directory of Open Access Journals (Sweden)

    G. Chen

    2012-01-01

    Full Text Available Cardiomyopathies are common cardiac disorders that primarily affect cardiac muscle resulting in cardiac dysfunction and heart failure. Transgenic mouse disease models have been developed to investigate the cellular mechanisms underlying heart failure and sudden cardiac death observed in cardiomyopathy cases and to explore the therapeutic outcomes in experimental animals in vivo. Echocardiography is an essential diagnostic tool for accurate and noninvasive assessment of cardiac structure and function in experimental animals. Our laboratory has been among the first to apply high-frequency research echocardiography on transgenic mice with cardiomyopathies. In this work, we have summarized our and other studies on assessment of systolic and diastolic dysfunction using conventional echocardiography, pulsed Doppler, and tissue Doppler imaging in transgenic mice with various cardiomyopathies. Estimation of embryonic mouse hearts has been performed as well using this high-resolution echocardiography. Some technical considerations in mouse echocardiography have also been discussed.

  18. Rats with high left ventricular end-diastolic pressure can be identified by Doppler echocardiography one week after myocardial infarction.

    Science.gov (United States)

    Saraiva, R M; Kanashiro-Takeuchi, R M; Antonio, E L; Campos, O; P J F, Tucci; Moisés, V A

    2007-11-01

    The severity of left ventricular (LV) dysfunction in rats with myocardial infarction (MI) varies widely. Because homogeneity in baseline parameters is essential for experimental investigations, a study was conducted to establish whether Doppler echocardiography (DE) could accurately identify animals with high LV end-diastolic pressure as a marker of LV dysfunction soon after MI. Direct measurements of LV end-diastolic pressure were made and DE was performed simultaneously 1 week after surgically induced MI (N = 16) or sham-operation (N = 17) in female Wistar rats (200 to 250 g). The ratio of peak early (E) to late (A) diastolic LV filling velocities and the ratio of E velocity to peak early (Em) diastolic myocardial velocity were the best predictors of high LV end-diastolic pressure (>12 mmHg) soon after MI. Cut-off values of 1.77 for the E/A ratio (P = 0.001) identified rats with elevated LV end-diastolic pressure with 90% sensitivity and 80% specificity. Cut-off values of 20.4 for the E/Em ratio (P = 0.0001) identified rats with elevated LV end-diastolic pressure with 81.8% sensitivity and 80% specificity. Moreover, E/A and E/Em ratios were the only echocardiographic parameters independently associated with LV end-diastolic pressure in multiple linear regression analysis. Therefore, DE identifies rats with high LV end-diastolic pressure soon after MI. These findings have implications for using serial DE in animal selection and in the assessment of their response to experimental therapies.

  19. The impact of total bile acid levels on fetal cardiac function in intrahepatic cholestasis of pregnancy using fetal echocardiography: a tissue Doppler imaging study.

    Science.gov (United States)

    Ataalla, Walid M; Ziada, Dina H; Gaber, Rania; Ossman, Ahmed; Bayomy, Suzan; Elemary, Berihan R

    2016-01-01

    The aim of this study was to assess total bile acid (TBA) levels and its impact on systolic and diastolic functions in fetuses of mothers with intrahepatic cholestasis of pregnancy (ICP) using tissue Doppler imaging (TDI), and to explore the correlation between TBA levels and fetal cardiac function. The study employed 98 pregnant women with ICP who were divided into two groups according to their bile acid levels. Fifty pregnant women without ICP represented the control group. Significant differences in the myocardial tissue velocities of both mitral and tricuspid valves were found between the fetuses of mothers with ICP and TBA levels of 40 mmol/L. There was a significant increase in neonatal respiratory distress, meconium staining and neonatal TBAs in group II compared to the control group and group I. There was a correlation between maternal TBA levels and preterm delivery, APGAR scores and neonatal TBA levels at birth. There was also a positive correlation between maternal TBA and fetal myocardial tissue velocities of both mitral and tricuspid, and fetal diastolic myocardial tissue Doppler velocities. ICP is a very serious condition especially when maternal TBA levels are >40 mmol/L. Fetal echocardiography with tissue Doppler is a useful tool for fetal assessment in patients with ICP. It could be an indication of induction of labor in cases of ICP and bile acid levels ≥40 mol/L. Neonatal echocardiography is mandatory for follow-up and management of these neonates.

  20. Relation Between Capillary Wedge Pressure Measured by Echocardiography Through Tissue Doppler Imaging (TDI Method and Catheterism in Patients with Mitral Valve Stenosis

    Directory of Open Access Journals (Sweden)

    Mashallah Dehghani

    2006-07-01

    Full Text Available Background: Considering suggested formula in the references and PCWP measured by catheterism, in the present study the relation between pulmonary capillary wedge pressure (PCWP measured the flow velocity of mitral valve and mitral annulus motion through tissue doppler imaging is evaluated Methods: 52 cases of severe MS were admitted for Balloon Mitral Valvolotomy (BMV are included in this study. Mean age was 35±5 years consisting of 40 females and 12 males. Valve area, Pulmonary artery systolic pressure (PAP, E (Maximum Velocity of mitral valve at the beginning of diastole & Em (Maximum rate of mitral annular motion at the beginning of diastole which is recorded through septal or lateral wall annulus site velocity and left atrial (LA size were also measured by echocardiography and PCWP & PAP through catheterism. All patients had normal ejection fraction (EF and coronary arteries; there was no other valvular diseases and shunts. Results: There was a significant correlation between PAP in echocardiography and catheterism. Mean PAP was 53±19 mmHg in echocardiography and 53.9±17.8mmHg in catheterism. There wasn't any correlation between PCWP in echocardiography and catheterism (P=0.33 and also no relation between PCWP and mitral valve area (MVA or LA size (P=0.2. E/Em ratio increased in severe MS cases.Conclusion: E/Em ratio and suggested formula would overestimate the wedge pressure so echocardiography is not a reliable method for measuring PCWP in severe MS. Em velocity and E/Em ratio may be used for estimating MS severity.

  1. Micro-Doppler Ambiguity Resolution for Wideband Terahertz Radar Using Intra-Pulse Interference.

    Science.gov (United States)

    Yang, Qi; Qin, Yuliang; Deng, Bin; Wang, Hongqiang; You, Peng

    2017-04-29

    Micro-Doppler, induced by micro-motion of targets, is an important characteristic of target recognition once extracted via parameter estimation methods. However, micro-Doppler is usually too significant to result in ambiguity in the terahertz band because of its relatively high carrier frequency. Thus, a micro-Doppler ambiguity resolution method for wideband terahertz radar using intra-pulse interference is proposed in this paper. The micro-Doppler can be reduced several dozen times its true value to avoid ambiguity through intra-pulse interference processing. The effectiveness of this method is proved by experiments based on a 0.22 THz wideband radar system, and its high estimation precision and excellent noise immunity are verified by Monte Carlo simulation.

  2. Micro-Doppler Ambiguity Resolution for Wideband Terahertz Radar Using Intra-Pulse Interference

    Directory of Open Access Journals (Sweden)

    Qi Yang

    2017-04-01

    Full Text Available Micro-Doppler, induced by micro-motion of targets, is an important characteristic of target recognition once extracted via parameter estimation methods. However, micro-Doppler is usually too significant to result in ambiguity in the terahertz band because of its relatively high carrier frequency. Thus, a micro-Doppler ambiguity resolution method for wideband terahertz radar using intra-pulse interference is proposed in this paper. The micro-Doppler can be reduced several dozen times its true value to avoid ambiguity through intra-pulse interference processing. The effectiveness of this method is proved by experiments based on a 0.22 THz wideband radar system, and its high estimation precision and excellent noise immunity are verified by Monte Carlo simulation.

  3. Early right ventricular systolic dysfunction in patients with systemic sclerosis without pulmonary hypertension: a Doppler Tissue and Speckle Tracking echocardiography study

    Directory of Open Access Journals (Sweden)

    Baumann Gert

    2010-01-01

    Full Text Available Abstract Background Isovolumetric acceleration (IVA is a novel tissue Doppler parameter for the assessment of systolic function. The aim of this study was to evaluate IVA as an early parameter for the detection of right ventricular (RV systolic dysfunction in patients with systemic sclerosis (SSc without pulmonary hypertension. Methods 22 patients and 22 gender- and age-matched healthy subjects underwent standard echocardiography with tissue Doppler imaging (TDI and speckle tracking strain to assess RV function. Results Tricuspid annular plane systolic excursion (TAPSE (23.2 ± 4.1 mm vs. 26.5 ± 2.9 mm, p 2 vs. 4.1 ± 0.8 m/s2, p Conclusion IVA is a useful tool with high-predictive power to detect early right ventricular systolic impairment in patients with SSc and without pulmonary hypertension.

  4. Performance of two-dimensional Doppler echocardiography for the assessment of infarct size and left ventricular function in rats.

    Science.gov (United States)

    Nozawa, E; Kanashiro, R M; Murad, N; Carvalho, A C C; Cravo, S L D; Campos, O; Tucci, P J F; Moises, V A

    2006-05-01

    Although echocardiography has been used in rats, few studies have determined its efficacy for estimating myocardial infarct size. Our objective was to estimate the myocardial infarct size, and to evaluate anatomic and functional variables of the left ventricle. Myocardial infarction was produced in 43 female Wistar rats by ligature of the left coronary artery. Echocardiography was performed 5 weeks later to measure left ventricular diameter and transverse area (mean of 3 transverse planes), infarct size (percentage of the arc with infarct on 3 transverse planes), systolic function by the change in fractional area, and diastolic function by mitral inflow parameters. The histologic measurement of myocardial infarction size was similar to the echocardiographic method. Myocardial infarct size ranged from 4.8 to 66.6% when determined by histology and from 5 to 69.8% when determined by echocardiography, with good correlation (r = 0.88; P echocardiography (r = -0.87; P rats.

  5. Performance of two-dimensional Doppler echocardiography for the assessment of infarct size and left ventricular function in rats

    OpenAIRE

    Nozawa E.; Kanashiro R.M.; Murad N.; Carvalho A.C.C.; Cravo S.L.D.; Campos O.; Tucci P.J.F.; Moises V.A.

    2006-01-01

    Although echocardiography has been used in rats, few studies have determined its efficacy for estimating myocardial infarct size. Our objective was to estimate the myocardial infarct size, and to evaluate anatomic and functional variables of the left ventricle. Myocardial infarction was produced in 43 female Wistar rats by ligature of the left coronary artery. Echocardiography was performed 5 weeks later to measure left ventricular diameter and transverse area (mean of 3 transverse planes), i...

  6. Correlation of ascending aorta elasticity and the severity of coronary artery stenosis in hypertensive patients with coronary heart disease assessed by M-mode and tissue Doppler echocardiography.

    Science.gov (United States)

    Lu, Qixiu; Liu, Houlin

    2015-03-01

    The main objective of this study is to investigate the relationship between ascending aorta elasticity and the severity of coronary artery stenosis in essential hypertensive patients with coronary heart disease (CHD) using M-mode and tissue Doppler echocardiography. A total of 184 hypertensive patients with CHD were enrolled. Patients were divided into three groups based on the severity of coronary stenosis measured by coronary arteriography (CAG): slight stenosis (group 1), moderate stenosis (group 2) and serious stenosis (group 3). M-mode and tissue Doppler echocardiography were performed, and elasticity indexes of ascending aorta including stiffness index, distensibility index, and S wave speed of anterior wall were calculated and correlated with the severity of coronary stenosis. Ascending aorta stiffness index was increased, whereas distensibility index and S wave speed of anterior wall were decreased in moderate and severe stenosis groups compared with slight stenosis group (P coronary artery, and there was a significant correlation between aortic elasticity and severity of coronary artery by Pearson correlation analysis (P coronary stenosis. Elasticity indexes of ascending aorta can serve as predictors for coronary arterial lesion in hypertensive patients.

  7. Value of systolic pulmonary venous flow reversal and color Doppler jet measurements assessed with transesophageal echocardiography in recognizing severe pure mitral regurgitation

    NARCIS (Netherlands)

    Pieper, EPG; Hellemans, IM; Hamer, HPM; Ravelli, ACJ; Cheriex, EC; Tijssen, JGP; Lie, KI; Visser, CA

    1996-01-01

    We evaluated the value of color and pulsed Doppler transesophageal echocardiographic parameters and of V waves in estimating the severity of mitral regurgitation (MR) in 62 consecutive patients (38 men and 24 women, aged 39 to 80 years) with angiographically proven chronic pure MR (15 grade I/II, 47

  8. SEVERAL PROBLEMS IN DESIGNING DBS SYSTEMS FOR AIRBORNE PULSE DOPPLER RADAR

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Some bases are presented for determining and calculating the airborne pulse doppler radar's DBS system parameters.Major problems discussed here are the limitation to the beam sharpening ratio and azimuth resolution, and the limitation to maximum pitch angle and minimum azimuth angle.Some basic formulas are given for calculating the batch processing period, framescan time and antenna rotating speed.Also discussed are the limiting condition and determining principle of the pulse repetition frequency.

  9. Differentiation of dysplastic nodule from hepatocellular carcinoma on contrast-enhanced power and pulsed Doppler US

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jung Hee; Baek, Seung Yon; Kang, Byung Chul; Chung, Hye Kyung [Ewha Womans University College of Medicine, Seoul (Korea, Republic of)

    2001-09-15

    The purpose of this study was to differentiate dysplastic (DN) from hepatocellular carcinoma (HCC) in patients with liver cirrhosis on contrast-enhanced power and pulsed Doppler US. Twenty-one patients with liver cirrhosis and a focal lesion were included. They consisted of biopsy proven 12 DNs (mean diameter; 1.8 cm, M : F = 5 :7, mean age 60) and 9 HCCs (mean diameter: 2.3 cm, M : F = 6 : 3,mean age 63). All the patients were prospectively examined with Acusion Computed Sonography 128XP/10 and 4 MHz vector transducer. Gray-scale US was done to assess the echogenicity of the focal lesion. Vascular flow signals within the focal lesion were examined with power Doppler US. After the injection of 7 ml (300 mg/ml) suspension of US contrast agent (Levovist, Schering, Berlin, Germary), vascular flow signals were graded to 4 grades on power Doppler US. Arterial and/or venous flow pattern on pulsed Doppler US were evaluated. Statistical analysis was done using chi-square method. On gray-scale US, 10 (83%) DNs showed hypoechogenicity and the other two (17%) showed hyperechogenicity 7 (78%) HCCs were hypoechoic and two (22%) were hyperechoic. On non-enhanced power Doppler US, all 12 cases (100%) of DNs had no vascular flow signal and four cases of nine HCCs (grade II: three, grade III: one) revealed vascular flow signals (p=0.429). On contrast-enhanced power Doppler US, 11 cases(92%) of DNs and all cases (100%) of HCCs showed increased vascular flow signals. Three (24%) of DNs and 7 (78%) of HCCs showed grade III and IV. There was a statistical difference in the grade of vascular flow signals between two groups (p=0.03). On pulsed Doppler US, the arterial flow was present in 2 (17%) DNs and 8 (89%) HCCs (p=0.002) and venous flow was present in 11 (92%) DNs and 5 (56%) HCCs. Combined flow appeared in 2 cases (16%) of DNs and 4 cases (44%) of HCCs. In differentiating DN from HCC, the higher probability of HCC can be considered if a focal lesion in cirrhotic patients has grade

  10. Ventricular synchronicity: observations comparing pulse flow and tissue Doppler assessment in a Chinese healthy adult cohort

    Institute of Scientific and Technical Information of China (English)

    QUAN Xin; ZHU Tian-gang; GUO Shi; MA Jian-xin; WANG Xin; GUO Ji-hong

    2012-01-01

    Background Mechanical asynchrony is an important parameter in predicting the response to cardiac resynchronization therapy,but detailed knowledge about cardiac timing in healthy persons is scarce.Therefore,in the current study,we sought to investigate the physiological status of interventricular synchronicity using pulse wave flow and tissue Doppler imaging in a healthy Chinese population.Methods Eighty-eight healthy volunteers underwent standard flow and tissue Doppler echocardiographic examinations.Ventricular inflow and outflow pulse wave flow Doppler patterns were recorded together with annulus pulse tissue Doppler imaging.Time intervals from the beginning of the QRS complex to the onset,peak and end of each wave were measured.Results The onsets of systole between left and right ventricles were highly synchronized by both imaging modalities.However,the left ventricle reached the peak flow ejection and peak mechanical contraction earlier than the right ventricle,(165.61±26.23) ms vs.(204.3±34.55) ms (P <0.01) and (133.62±26.19) ms vs.(191.25±38.47) ms (P <0.01).Time to peak early diastolic relaxation was earlier in the left ventricle than in the right heart,(500.23±56.52) me vs.(524.94±47.42) ms (P <0.01).Conclusions Left and right ventricles were well synchronized at the onsets of systole and diastole even though interventricular peak systolic and peak early diastolic dyssynchrony was observed in healthy people by pulse wave Doppler imaging.In addition,diastolic timing events were slightly affected by age and gender.

  11. The influence of sulindac on diabetic cardiomyopathy: a non-invasive evaluation by Doppler echocardiography in streptozotocin-induced diabetic rats.

    Science.gov (United States)

    Krishna, Kota M; Gopal, Gopisetty S; Chalam, Chitrapu R V; Madan, Kalagara; Kumar, Veeravalli K; Prakash, Gomedhikam J; Annapurna, Akula

    2005-08-01

    The aim of the present study was to investigate the cardioprotective activity of sulindac as an aldose reductase inhibitor in the development of cardiomyopathy by non-invasive techniques; M-mode and Doppler echocardiography. Diabetes was induced by streptozotocin (45 mg/kg, iv) in the Sprague-Dawley rats. Echocardiography, biochemical and histological studies were carried out in normal control, diabetic untreated, diabetic vehicle (sodium carboxy methyl cellulose, 1%, po) and sulindac (6 mg/kg and 20 mg/kg, po) treated animals at varying time intervals. In the diabetic untreated and vehicle treated rats at 12 weeks after induction of diabetes, there was a significant decrease in the E-wave, an increase in the A-wave and corresponding decrease in the E/A ratio was observed. Significant decrease in the Eat was found after 12 weeks (P rats (P rats, whereas in the sulindac (6 mg/kg) treated rats, minimal necrosis was found, with no evidence of necrosis in sulindac (20 mg/kg) group. Our results show for the first time that sulindac has a cardioprotective activity as this agent prevented the development of left ventricular dysfunction in STZ-induced diabetic rats in the 12-week chronic study.

  12. Performance of two-dimensional Doppler echocardiography for the assessment of infarct size and left ventricular function in rats

    Directory of Open Access Journals (Sweden)

    Nozawa E.

    2006-01-01

    Full Text Available Although echocardiography has been used in rats, few studies have determined its efficacy for estimating myocardial infarct size. Our objective was to estimate the myocardial infarct size, and to evaluate anatomic and functional variables of the left ventricle. Myocardial infarction was produced in 43 female Wistar rats by ligature of the left coronary artery. Echocardiography was performed 5 weeks later to measure left ventricular diameter and transverse area (mean of 3 transverse planes, infarct size (percentage of the arc with infarct on 3 transverse planes, systolic function by the change in fractional area, and diastolic function by mitral inflow parameters. The histologic measurement of myocardial infarction size was similar to the echocardiographic method. Myocardial infarct size ranged from 4.8 to 66.6% when determined by histology and from 5 to 69.8% when determined by echocardiography, with good correlation (r = 0.88; P < 0.05; Pearson correlation coefficient. Left ventricular diameter and mean diastolic transverse area correlated with myocardial infarct size by histology (r = 0.57 and r = 0.78; P < 0.0005. The fractional area change ranged from 28.5 ± 5.6 (large-size myocardial infarction to 53.1 ± 1.5% (control and correlated with myocardial infarct size by echocardiography (r = -0.87; P < 0.00001 and histology (r = -0.78; P < 00001. The E/A wave ratio of mitral inflow velocity for animals with large-size myocardial infarction (5.6 ± 2.7 was significantly higher than for all others (control: 1.9 ± 0.1; small-size myocardial infarction: 1.9 ± 0.4; moderate-size myocardial infarction: 2.8 ± 2.3. There was good agreement between echocardiographic and histologic estimates of myocardial infarct size in rats.

  13. Study on the method of polarization suppression of cheating jamming in pulse Doppler radar

    Institute of Scientific and Technical Information of China (English)

    Song Lizhong; Qiao Xiaolin; Meng Xiande; Jin Ming

    2005-01-01

    A jamming suppression method based on polarization signal detection is proposed under common range and velocity cheating jammingfor pulse Doppler radar. On the basis of the separation of the target and the jamming, the range and velocity track on the true target are realized. Firstly the signal processing model of the full polarization pulse Doppler radar is introduced. Secondly the method of correct target separation is discussed, which is the twice detections of energy and polarization state on the two dimension resolution cells of range and velocity of the radar echo. Finally the simulations are performed and the results prove the validity. What' s more, multiple range and velocity cheating jamming can be suppressed at the same time if the target and the jamming are different in the polarization domain.

  14. Analysis of the computational requirements of a pulse-doppler radar signal processor

    CSIR Research Space (South Africa)

    Broich, R

    2012-05-01

    Full Text Available architectures [1]. These simplifications are often degrading to algorithmic performance and thus to the entire radar system. In this paper the different computational operations that are used in pulse-Doppler radar signal processing are explored, in order...H z to 10 GH z Fig. 1. Radar signal processor (RSP) flow of operations purpose computer architectures [3]. An abstract machine, in which only memory reads, writes, additions and multiplica- tions are considered to be significant operations...

  15. Novel Method of Unambiguous Moving Target Detection in Pulse-Doppler Radar with Random Pulse Repetition Interval

    Directory of Open Access Journals (Sweden)

    Liu Zhen

    2012-03-01

    Full Text Available Blind zones and ambiguities in range and velocity measurement are two important issues in traditional pulse-Doppler radar. By generating random deviations with respect to a mean Pulse Repetition Interval (PRI, this paper proposes a novel algorithm of Moving Target Detection (MTD based on the Compressed Sensing (CS theory, in which the random deviations of the PRIare converted to the Restricted Isometry Property (RIP of the observing matrix. The ambiguities of range and velocity are eliminated by designing the signal parameters. The simulation results demonstrate that this scheme has high performance of detection, and there is no ambiguity and blind zones as well. It can also shorten the coherent processing interval compared to traditional staggered PRI mode because only one pulse train is needed instead of several trains.

  16. Tissue Doppler echocardiography reveals distinct patterns of impaired myocardial velocities in different degrees of coronary artery disease

    DEFF Research Database (Denmark)

    Hoffmann, Soren; Mogelvang, Rasmus; Olsen, Niels Thue

    2010-01-01

    Aim To determine how the left ventricular wall motion assessed by echocardiographic Tissue Doppler Imaging (TDI) is affected by increasing severity of coronary artery disease (CAD) among patients with stable angina pectoris and preserved ejection fraction. METHODS AND RESULTS: This study comprises.......86 +/- 0.24 vs. 1.00 +/- 0.28, P preserved ejection fraction reveals both diastolic and systolic dysfunction and the nature...

  17. Eye-safe,single-frequency pulsed all-fiber laser for Doppler wind lidar

    Institute of Scientific and Technical Information of China (English)

    Yuan Liu; Jiqiao Liu; Weibiao Chen

    2011-01-01

    @@ A single-frequency pulsed erbium-doped fiber(EDF)laser with master-oscillator Dower-amplifier comiguration at t bass nm is developed.A short-cavity,erbium-doped phosphate class fiber laser is utilized as a seeaer laser wntn a unewidtn of b khz and power of 40 mW.The seeder laser is modulated to be a pulse laser with a repetition rate of 10 kHz and pulse duration of 500 ns.The amplifier consists of two pre-amplifiers and one main amplifier.The detailed characteristics of the spectrum and linewidth of the amplifiers are presented.A pulse energy of 116 pJ and a linewidth of 1.1 MHz are obtained.This laser can be a candidate transmitter for an all-fiber Doppler wind lidar in the boundarv laver.%A single-frequency pulsed erbium-doped fiber (EDF) laser with master-oscillator power-amplifier configuration at 1533 nm is developed. A short-cavity, erbium-doped phosphate glass fiber laser is utilized as a seeder laser with a linewidth of 5 kHz and power of 40 mW. The seeder laser is modulated to be a pulse laser with a repetition rate of 10 kHz and pulse duration of 500 ns. The amplifier consists of two pre-amplifiers and one main amplifier. The detailed characteristics of the spectrum and linewidth of the amplifiers are presented. A pulse energy of 116 μJ and a linewidth of 1.1 MHz are obtained. This laser can be a candidate transmitter for an all-fiber Doppler wind lidar in the boundary layer.

  18. Evaluation of Acoustic Doppler Velocimeters (ADVs) and Pulse Coherent Acoustic Doppler Profiler (PCADP) in Estimating Suspended Sediment Concentration

    Science.gov (United States)

    Ha, H.; Maa, J.

    2008-12-01

    Laboratory experiments were conducted to estimate the suspended sediment concentration (SSC) or its profile using acoustic backscatter strengths. Three acoustic Doppler velocimeters (ADVs) with different frequencies (5, 10 and 16 MHz) and a pulse coherent acoustic Doppler profiler (PCADP) with 1.5 MHz were used with selected sediments: two different commercial clays and Clay Bank sediment in the York River. Each ADV showed different backscatter responses depending on the sediment type and SSC. Not all devices had a good linear relationship between backscatter strength and SSC. Within a limited range of SSC, however, the backscatter strength can be well correlated with the SSC. Compared with optical backscatter sensor (OBS), ADV's backscatter signals were too noisy to be directly converted to the fluctuation of SSC, due to high amplification ratio and small sampling volume. There is another unexpected response for the backscatter strength: high signals from small particles but low signals from large particles. This might be caused by the internal gain setting built in ADVs, which should be further clarified. For profiling the SSC, a PCADP was tested in a controlled water tank. The sound attenuation by sediments was included in the signal inversion algorithm since most target regions measured by PCADP are located at near-bed high concentration layer. Clay Bank sediment showed a higher correlation coefficient (r2=0.92) between range- corrected volume scattering and PCADP signal when SSCcontrolled by the particle size in suspension at a given frequency. The profiling test for Clay Bank sediments showed that the PCADP-derived SSC profile has a good agreement with sample- and OBS-derived outcomes. This study suggests that both ADV and PCADP are useful instruments to estimate the SSC if the aforementioned questions are clarified and the particle (floc) size is sufficiently large enough to be sensed.

  19. 弯刀综合征的超声心动图诊断价值探讨%Value of color Doppler echocardiography in diagnosis of scimitar syndrome

    Institute of Scientific and Technical Information of China (English)

    曹睿; 刘特长; 于明华; 张明杰; 陈欣欣; 虢艳; 李健茹; 王莉

    2015-01-01

    目的:探讨弯刀综合征的经胸彩色多普勒超声心动图诊断价值。方法回顾6例弯刀综合征患儿的超声图像,结合文献分析超声心动图特征及其血流动力学。结果6例弯刀综合征患儿右位心或中位心各3例,右心扩大6例,全部或部分右肺静脉异位引流至下腔静脉各3例,6例右肺动脉发育不良,均与CT血管造影(CT angiography ,CTA)相符,其中4例经手术证实。结论弯刀综合征的超声图像特征明显,可为其早期诊断与治疗提供有价值的信息。%Objective To discuss the value of color Doppler echocardiography in diagnosis of scimitar syndrome .Methods The echocardiographic results of 6 patients with a diagnosis of scimitar syndrome were reviewed retrospectively .Their sonographic and hemodynamic characteristics were also analyzed connected with the reports in the literature .Results Three cases had dextrocardia and the others had mesocardia .All cases got right ventricular dimension enlargement .Total or partial of right pulmonary venous connection to the inferior vena cava were 3 cases respectively .All cases had right pulmonary artery hypoplasia .All of 6 cases echocardiographic results were in accordance with the findings by CT angiography and 4 cases were confirmed by operation .Conclusions The sonographic features of scimitar syndrome were obvious ,and echocardiography was contribute to early diagnosis of scimitar syndrome .

  20. Non-invasive evaluation of myocardial reperfusion by transthoracic Doppler echocardiography and single-photon emission computed tomography in patients with anterior acute myocardial infarction

    Directory of Open Access Journals (Sweden)

    Celutkiene Jelena

    2011-05-01

    Full Text Available Abstract Background The study was designed to evaluate whether the preserved coronary flow reserve (CFR 72 hours after reperfused acute myocardial infarction (AMI is associated with less microvascular dysfunction and is predictive of left ventricular (LV functional recovery and the final infarct size at follow-up. Methods In our study, CFR was assessed by transthoracic Doppler echocardiography (TDE in 44 patients after the successful percutaneous coronary intervention during the acute AMI phase. CFR was correlated with contractile reserve assessed by low-dose dobutamine echocardiography and with the total perfusion defect measured by single-photon emission computed tomography 72 hours after reperfusion and at 5 months follow-up. The ROC analysis was performed to determine test sensitivity and specificity based on CFR. Categorical data were compared by an χ2 analysis, continuous variables were analysed with the independent Student's t test. In order to analyse correlation between CFR and the parameters of LV function and perfusion, the Pearson correlation analysis was conducted. The linear regression analysis was used to assess the relationship between CFR and myocardial contractility as well as the final infarct size. Results We estimated the CFR cut-off value of 1.75 as providing the maximal accuracy to distinguish between patients with preserved and impaired CFR during the acute AMI phase (sensitivity 91.7%, specificity 75%. Wall motion score index was better in the subgroup with preserved CFR as compared to the subgroup with reduced CFR: 1.74 (0.29 vs. 1.89 (0.17 (p Conclusion The early measurement of CFR by TDE can be of high value for the assessment of successful reperfusion in AMI and can be used to predict LV functional recovery, myocardial viability and the final infarct size.

  1. Model experiments on imaging subsurface fracture permeability by pulsed Doppler borehole televiewer; Pulse doppler borehole televiewer ni yoru kiretsu tosuisei hyoka ni kansuru model jikken

    Energy Technology Data Exchange (ETDEWEB)

    Inagaki, Y.; Niitsuma, H. [Tohoku University, Sendai (Japan). Faculty of Engineering

    1996-05-01

    This paper reports model experiments to evaluate flow rates of fluids passing through a fracture by using a Doppler borehole televiewer (DBHTV). A supersonic transducer disposed on a well axis transmits transmission pulses, and a transducer receives scattered waves generated by particulates in water and waves reflected on a well wall. This signal is applied with time gating to extract only the scattered waves from particulates in the vicinity of the well wall. Deriving spectra in the recorded Doppler signal obtains flow velocity components in the direction of the well radius. A model was made with a polyvinylchloride pipe with a diameter of 14.6 cm to simulate a well, to which an aluminum pipe with an inner diameter of 2 mm is connected to be used as a simulated fracture, and mud water is circulated in the pipe. The result of deriving a passed flow volume in this model by integrating flow rate distribution derived by using the above method to a predetermined range in the vicinity of the fracture showed a good proportional relationship with actual flow rate in the simulated fracture. 1 ref., 7 figs.

  2. [Doppler effect on width of characteristic line in plasma induced by pulsed laser ablating Al].

    Science.gov (United States)

    Song, Yi-Zhong; He, An-Zhi

    2005-05-01

    Aluminum (Al) plasma was induced with a pulsed Nd: YAG laser beam ablating Al target in Ar. Time-resolved information of the plasma radiation was taken with time-resolved technique, and the spectra of the radiation were recorded with an optical multi-path analyzer (OMA III ), whereupon, time-resolved spectra of the plasma radiation induced by pulsed laser were acquired. Based on the experiment data, Al resonant double lines, Al I 396.15 nm, Al I 394.40 nm, were respectively fitted with Lorentz, Gauss and their linear integrated function (abbr. Integrated function), whereupon, Lorentz and Gauss elements were separated from the experiment data profile curve. By contrasting Lorentz with Gauss curve separated, it was found that the experiment curve mainly consisted of Lorentz element, a with little Gauss. By contrasting Lorentz with Integrated fitting curve for experiment data, a visual picture of the characteristic lines broadened by Doppler effect was exhibited. According to the visual picture, the increase of full half-high width of the characteristic line broadened by Doppler effect was estimated. It was about 2 x 10(-)3 -8 x 10(-3) nm, approximating the theoretical value 6.7 x 10(-)3 nm. As a result, Doppler effect on the width of characteristic lines in the plasma could be reasonably explained by curve fitting analysis and theoretical calculation.

  3. Comparing Pulsed Doppler LIDAR with SODAR and Direct Measurements for Wind Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kelley, N. D.; Jonkman, B. J.; Scott, G. N.; Pichugina, Y. L.

    2007-07-01

    There is a pressing need for good wind-speed measurements at greater and greater heights to assess the availability of the resource in terms of power production and to identify any frequently occurring atmospheric structural characteristics that may create turbulence that impacts the operational reliability and lifetime of wind turbines and their components. In this paper, we summarize the results of a short study that compares the relative accuracies of wind speeds derived from a high-resolution pulsed Doppler LIDAR operated by the National Oceanic and Atmospheric Administration (NOAA) and a midrange Doppler SODAR with wind speeds measured by four levels of tower-based sonic anemometry up to a height of 116 m.

  4. Venstre ventrikels diastoliske funktion vurderet med transtorakal Doppler-ekkokardiografi

    DEFF Research Database (Denmark)

    Poulsen, S H; Jensen, S E; Gøtzsche, O;

    1996-01-01

    Left ventricular diastolic dysfunction is currently recognized in patients with different heart diseases. Three abnormal filling patterns of the left ventricle detected by pulsed-Doppler echocardiography are observed in patients with heart disease. Each filling pattern is characterised by differe...

  5. Acute Effects of an Energy Drink on Myocardial Function Assessed by Conventional Echo-Doppler Analysis and by Speckle Tracking Echocardiography on Young Healthy Subjects

    Directory of Open Access Journals (Sweden)

    Daniele Menci

    2013-01-01

    Full Text Available Purpose. Previous studies have underlined the effects of the energy drinks containing caffeine end taurine on the cardiovascular system. The aim of this study was to determine acute changes on echocardiographic parameters assessed by conventional echo-Doppler analysis and by speckle tracking echocardiography after the consumption of an energy drink in a young healthy population. Methods. measurement of blood pressure, electrocardiographic, and echocardiographic examination were performed on 35 healthy subjects (mean age 25 ± 2 years, 16 men, at baseline and one hour after the consumption of a body surface area indexed amount of an energy drink (168 mL/m2 containing caffeine (0.03% and taurine (0.4%. Results. The analysis of left ventricular function showed a significant increase of mean relative values of MAPSE (+11%; , global longitudinal strain (+10%, , and left ventricular twisting (+22%, in respect to baseline. Also, right ventricular function parameters appeared significantly increased after energy drink consumption, as TAPSE (+15%, , global, and free wall right ventricular longitudinal strain (+8%, ; +5%, , resp.. Conclusion. In conclusion, the consumption of the ED in our population showed a significant increase of right and left ventricular myocardial function, suggesting a possible positive inotropic effect related to the substances contained therein.

  6. Acute effects of an energy drink on myocardial function assessed by conventional echo-Doppler analysis and by speckle tracking echocardiography on young healthy subjects.

    Science.gov (United States)

    Menci, Daniele; Righini, Francesca Maria; Cameli, Matteo; Lisi, Matteo; Benincasa, Susanna; Focardi, Marta; Mondillo, Sergio

    2013-01-01

    Purpose. Previous studies have underlined the effects of the energy drinks containing caffeine end taurine on the cardiovascular system. The aim of this study was to determine acute changes on echocardiographic parameters assessed by conventional echo-Doppler analysis and by speckle tracking echocardiography after the consumption of an energy drink in a young healthy population. Methods. measurement of blood pressure, electrocardiographic, and echocardiographic examination were performed on 35 healthy subjects (mean age 25 ± 2 years, 16 men), at baseline and one hour after the consumption of a body surface area indexed amount of an energy drink (168 mL/m(2)) containing caffeine (0.03%) and taurine (0.4%). Results. The analysis of left ventricular function showed a significant increase of mean relative values of MAPSE (+11%; P < 0.001), global longitudinal strain (+10%, P = 0.004), and left ventricular twisting (+22%, P < 0.0001) in respect to baseline. Also, right ventricular function parameters appeared significantly increased after energy drink consumption, as TAPSE (+15%, P < 0.0001), global, and free wall right ventricular longitudinal strain (+8%, P = 0.001; +5%, P = 0.1, resp.). Conclusion. In conclusion, the consumption of the ED in our population showed a significant increase of right and left ventricular myocardial function, suggesting a possible positive inotropic effect related to the substances contained therein.

  7. Fpga based L-band pulse doppler radar design and implementation

    Science.gov (United States)

    Savci, Kubilay

    As its name implies RADAR (Radio Detection and Ranging) is an electromagnetic sensor used for detection and locating targets from their return signals. Radar systems propagate electromagnetic energy, from the antenna which is in part intercepted by an object. Objects reradiate a portion of energy which is captured by the radar receiver. The received signal is then processed for information extraction. Radar systems are widely used for surveillance, air security, navigation, weather hazard detection, as well as remote sensing applications. In this work, an FPGA based L-band Pulse Doppler radar prototype, which is used for target detection, localization and velocity calculation has been built and a general-purpose Pulse Doppler radar processor has been developed. This radar is a ground based stationary monopulse radar, which transmits a short pulse with a certain pulse repetition frequency (PRF). Return signals from the target are processed and information about their location and velocity is extracted. Discrete components are used for the transmitter and receiver chain. The hardware solution is based on Xilinx Virtex-6 ML605 FPGA board, responsible for the control of the radar system and the digital signal processing of the received signal, which involves Constant False Alarm Rate (CFAR) detection and Pulse Doppler processing. The algorithm is implemented in MATLAB/SIMULINK using the Xilinx System Generator for DSP tool. The field programmable gate arrays (FPGA) implementation of the radar system provides the flexibility of changing parameters such as the PRF and pulse length therefore it can be used with different radar configurations as well. A VHDL design has been developed for 1Gbit Ethernet connection to transfer digitized return signal and detection results to PC. An A-Scope software has been developed with C# programming language to display time domain radar signals and detection results on PC. Data are processed both in FPGA chip and on PC. FPGA uses fixed

  8. Pulsed multigated Doppler ultrasonography in the diagnosis of carotid artery disease

    DEFF Research Database (Denmark)

    Sillesen, H; Bitsch, K R; Schroeder, T

    1988-01-01

    To evaluate the accuracy of a pulsed multigated Doppler system, 128 carotid arteries were examined. The spectral broadening index was calculated from the power spectrum of a small sample volume located in the center of the stream according to the flow profile and was related to the degree...... of stenosis as determined by contrast angiography. Even minor wall irregularities seen on the angiogram were classified as disease. The ability of the system to discriminate between normal and diseased vessels reached a sensitivity of 94% and a specificity of 91%. Classification of greater than 50% or less...

  9. Evaluation of Pulsed Doppler-Versus Tissue Doppler-Derived Tei Index of Right and Left Ventricle in Fetuses

    Directory of Open Access Journals (Sweden)

    Hamid Amoozgar

    2011-12-01

    Full Text Available Background: The myocardial performance index (MPI, also known as the Tei index, was introduced by Tei et al. to evaluate cardiac function in adults with dilated cardiomyopathy. This index is defined as the sum of isovolumic contraction time (ICT and isovolumic relaxation time (IRT, divided by ejection time (ET. Objectives: To determine the correlation between pulsed Doppler (PD- and tissue Doppler imaging (TDI-derived Tei indices in fetuses. Patients and Methods: Right and left ventricle PD and TDI echocardiographic data were obtained from 59 fetuses (11 pregnant women who were positive for anti-SSA-Ro or anti-SSB-La antibodies, 18 women who were referred due to dysrhythmia, and 30 women who had normal clinical findings. Results: Mean fetal gestational age was 27 ± 6.4 weeks. Mean PD Tei index of the mitral and tricuspid valve was 0.58 ± 0.05 and 0.53 ± 0.08, respectively. Mean TDI indices for the mitral and tricuspid valve were 0.56 ± 0.09 and 0.55 ± 0.08, respectively. There were no significant differences between mitral and tricuspid PD- and TDI-derived Tei indices (P = 0.87, P= 0.21, but the Bland-Altman diagrams showed no fine agreement between the indices (the mean difference ± 1 standard deviation of the right ventricular PD- and TDI-derived Tei indices was 0.24 ± 0.02 and 0.29 ± 0.04 for the left ventricle. There were no significant differences in PD- and TDI-derived Tei indexes between groups of evaluated fetuses (Mitral valve: PD-Tei P=0.69, TDI-Tei P=0.49; Tricuspid valve: PD-Tei P=0.41, TDI-Tei P=0.36. Conclusions: Although the mean values of the two indices did not differ significantly, the TDI-derived and PD-derived Tei indices did not have fine agreement.

  10. Right ventricular function assessed by tissue Doppler echocardiography in older subjects without evidence for structural cardiac disease.

    Science.gov (United States)

    Laszlo, Roman; Baumann, Tobias; Konz, Hanna; Dallmeier, Dhayana; Klenk, Jochen; Denkinger, Michael; Koenig, Wolfgang; Rothenbacher, Dietrich; Steinacker, Juergen Michael

    2016-05-31

    The aim of our study was to obtain right ventricular (RV) tissue Doppler imaging (TDI) data in older subjects (n = 95, mean age: 74.5 ± 4.6 years) without evidence of hemodynamically significant structural heart disease recruited from a large population-based cohort (ActiFE-Ulm study). Our data indicate that aging may be accompanied by decreasing RV diastolic function and at most little alterations of RV systolic function. Mean values of all parameters were still within the guideline-suggested reference range with most of them closer to the abnormality thresholds. On an individual basis, respective thresholds were also exceeded in some subjects (almost all parameters subjects, presumed pathological measures might still be compatible with physiological age-related alterations. Therefore, they always have to be interpreted across the clinical context and in relation to other parameters of morphology and function obtained by other ultrasound imaging techniques (M-mode, B-mode, etc.) in the context of echocardiographic evaluation of the right heart.

  11. Pulsed UCN production using a Doppler shifter at J-PARC

    CERN Document Server

    Imajo, S; Kitaguchi, M; Iwashia, Y; Yamada, N L; Hino, M; Oda, T; Ino, T; Shimizu, H M; Yamashita, S; Katayama, R

    2015-01-01

    We have constructed a Doppler-shifter-type pulsed ultra-cold neutron (UCN) source at the Materials and Life Science Experiment Facility (MLF) of the Japan Proton Accelerator Research Complex (J-PARC). Very-cold neutrons (VCNs) with 136-$\\mathrm{m/s}$ velocity in a neutron beam supplied by a pulsed neutron source are decelerated by reflection on a m=10 wide-band multilayer mirror, yielding pulsed UCN. The mirror is fixed to the tip of a 2,000-rpm rotating arm moving with 68-$\\mathrm{m/s}$ velocity in the same direction as the VCN. The repetition frequency of the pulsed UCN is $8.33~\\mathrm{Hz}$ and the time width of the pulse at production is $4.4~\\mathrm{ms}$. In order to increase the UCN flux, a supermirror guide, wide-band monochromatic mirrors, focus guides, and a UCN extraction guide have been newly installed or improved. The count rate of the output neutrons with longitudinal wavelengths longer than $58~\\mathrm{nm}$ is $1.6 \\times 10^{2}~\\mathrm{cps}$, while that of the true UCNs is $80~\\mathrm{cps}$ at ...

  12. Indicaciones básicas para la realización de ecocardiografía-Doppler-color Basic indications for the performance of color Doppler echocardiography

    Directory of Open Access Journals (Sweden)

    Fernando Manzur

    2005-06-01

    physiopathology give sufficient bases for the clinical decision assessment and emphasizes the evidence’s examination for the clinical investigation. The comprehension of certain evidence rules is necessary for the correct interpretation of literature in respect to the causes, diagnostic tools and treatment strategies. The main aim of this research is to make a protocol for the indications of an echocardiogram in the clinical practice and to educate our country’s general physicians in this conduct. The good practice is due to initiatives, activities and functional models that are in progress worldwide, as confirmed by evidence. Objective: echocardiography is actually the gold standard for the study of heart anatomy and physiology. Since its introduction in the clinical practice more than three decades ago, it has had such diffusion that it is considered an important tool in the cardiology assistance. It provides trustworthy functional anatomic information, as well as diagnosis and is decisive in the treatment and resolution of cardiovascular diseases. The progressive development of this technique has enabled its use in all the different fields that may affect the cardiovascular system. The objective is to help the clinical physicians in the making of decisions in concrete situations, guaranteeing them that the diagnosis is based on results given by valid scientific studies. In accordance to this, different studies as well as task force and management guides representative of the worldwide literature, were compiled.

  13. Development of ultrasonic pulse-train Doppler method for velocity profile and flowrate measurement

    Science.gov (United States)

    Wada, Sanehiro; Furuichi, Noriyuki; Shimada, Takashi

    2016-11-01

    We present a novel technique for measuring the velocity profile and flowrate in a pipe. This method, named the ultrasonic pulse-train Doppler method (UPTD), has the advantages of expanding the velocity range and setting the smaller measurement volume with low calculation and instrument costs in comparison with the conventional ultrasonic pulse Doppler method. The conventional method has limited measurement of the velocity range due to the Nyquist sampling theorem. In addition, previous reports indicate that a smaller measurement volume increases the accuracy of the measurement. In consideration of the application of the conventional method to actual flow fields, such as industrial facilities and power plants, the issues of velocity range and measurement volume are important. The UPTD algorithm, which exploits two pulses of ultrasound with a short interval and envelope detection, is proposed. Velocity profiles calculated by this algorithm were examined through simulations and excellent agreement was found in all cases. The influence of the signal-to-noise ratio (SNR) on the algorithm was also estimated. The result indicates that UPTD can measure velocity profiles with high accuracy, even under a small SNR. Experimental measurements were conducted and the results were evaluated at the national standard calibration facility of water flowrate in Japan. Every detected signal forms a set of two pulses and the enveloped line can be observed clearly. The results show that UPTD can measure the velocity profiles over the pipe diameter, even if the velocities exceed the measurable velocity range. The measured flowrates were under 0.6% and the standard deviations for all flowrate conditions were within  ±0.38%, which is the uncertainty of the flowrate measurement estimated in the previous report. In conclusion, UPTD provides superior accuracy and expansion of the velocity range.

  14. Phase noise in pulsed Doppler lidar and limitations on achievable single-shot velocity accuracy

    Science.gov (United States)

    Mcnicholl, P.; Alejandro, S.

    1992-01-01

    The smaller sampling volumes afforded by Doppler lidars compared to radars allows for spatial resolutions at and below some sheer and turbulence wind structure scale sizes. This has brought new emphasis on achieving the optimum product of wind velocity and range resolutions. Several recent studies have considered the effects of amplitude noise, reduction algorithms, and possible hardware related signal artifacts on obtainable velocity accuracy. We discuss here the limitation on this accuracy resulting from the incoherent nature and finite temporal extent of backscatter from aerosols. For a lidar return from a hard (or slab) target, the phase of the intermediate frequency (IF) signal is random and the total return energy fluctuates from shot to shot due to speckle; however, the offset from the transmitted frequency is determinable with an accuracy subject only to instrumental effects and the signal to noise ratio (SNR), the noise being determined by the LO power in the shot noise limited regime. This is not the case for a return from a media extending over a range on the order of or greater than the spatial extent of the transmitted pulse, such as from atmospheric aerosols. In this case, the phase of the IF signal will exhibit a temporal random walk like behavior. It will be uncorrelated over times greater than the pulse duration as the transmitted pulse samples non-overlapping volumes of scattering centers. Frequency analysis of the IF signal in a window similar to the transmitted pulse envelope will therefore show shot-to-shot frequency deviations on the order of the inverse pulse duration reflecting the random phase rate variations. Like speckle, these deviations arise from the incoherent nature of the scattering process and diminish if the IF signal is averaged over times greater than a single range resolution cell (here the pulse duration). Apart from limiting the high SNR performance of a Doppler lidar, this shot-to-shot variance in velocity estimates has a

  15. The impact of left ventricular preload reduction on cardiac pulsed doppler indices during hemodialysis and its relation to intra-dialysis hypotension: A pulsed doppler study

    Directory of Open Access Journals (Sweden)

    Alarrayed Sameer

    2009-01-01

    Full Text Available Fluid status in the body plays an important role on left ventricular (LV filling in patients with end-stage renal disease (ESRD on regular hemodialysis (HD, and plays a role in intra-dialysis hemo-dynamic derangement. Fifty-two patients with ESRD on regular HD, including 34 males with a mean age of 45.5 ± 13 years (range 18-72 years, were studied. All patients underwent Echo-pulsed Doppler study before and immediately after a HD session. The Echo Doppler indices noted were: LV cavity dimension and wall thickness, LV ejection fraction (LVEF%, trans-mitral early diastolic filling velocity (E wave, atrial filling diastolic velocity (A wave, E/A ratio, Deceleration Time (DT of E wave, Isovolumic relaxation time (IVRT, Aortic Velocity Integral (AVI and Inferior Vena Cava Diameter (VCD at expiration. Patients were divided into two groups according to the amount of net ultra filtrate loss after HD. Group I comprised of 25 patients with fluid loss of < 2 liters, and Group II had 27 patients with fluid loss > 2 liters. During the HD session, each patient was observed for the development of acute clinical events such as arterial hypotension (systolic BP less than 90 mmHg, chest pain and arrhythmias. There was a significant difference between the two groups in the mean values, pre- and post- HD, of reduction of E wave velocity (p< 0.01, the reduction of E/A ratio (p< 0.05, the increment in DT of E wave (p< 0.05, the reduction in AVI (p< 0.01 and the reduction of VCD (p< 0.05. There was no significant difference between the groups in the reduction of A wave velocity and the reduction of IVRT. Among the study patients, 11 (21% developed systolic hypo-tension during HD. The pre-dialysis mean values of E/A ratio and DT of E wave in patients who developed hypotension compared to those who did not was 0.7 ± 0.2 vs 1.1 ± 0.2.1 (p< 0.001 and 246 ± 40 vs 224 ± 34 msec (p< 0.05, respectively. Our study suggests that preload reduction in patients with ESRD on

  16. Assessment of the ability of myocardial contrast echocardiography with harmonic power Doppler imaging to identify perfusion abnormalities in patients with Kawasaki disease at rest and during dipyridamole stress.

    Science.gov (United States)

    Ishii, M; Himeno, W; Sawa, M; Iemura, M; Furui, J; Muta, H; Sugahara, Y; Egami, K; Akagi, T; Ishibashi, M; Kato, H

    2002-01-01

    The aim of our study was to assess the ability of myocardial contrast echocardiography (MCE) with harmonic power Doppler imaging (HPDI) to identify perfusion abnormalities in patients with Kawasaki disease at rest and during pharmacological stress imaging with dipyridamole. Results were compared with those of 99mTc-tetrofosmin single-photon emission computed tomography (SPECT) imaging as the clinical reference standard. MCE with HPDI was performed on 20 patients with a history of Kawasaki disease. Images were obtained at baseline and during dipyridamole infusion (0.56 mg x kg(-1)) in the apical two- and four-chamber views. Myocardial opacification suitable for the analysis was obtained in all patients. Nine patients with stenotic lesions had a reversible defect after dipyridamole infusion detected by both MCE with HPDI and SPECT, and 3 patients with a history of myocardial infarction had a partially or completely irreversible defect detected by both methods. Three patients with coronary aneurysm without stenotic lesion, 4 patients with regressed coronary aneurysm, and 2 patients with normal coronary artery in acute phase also had normal perfusion at rest and after pharmacological stress by both methods. A 96% concordance (kappa = 0.87) was obtained when comparing the respective segmental perfusion scores using the two methods at baseline, and an 86% concordance (kappa = 0.81) was obtained at postdipyridamole infusion. After combining baseline and postdipyridamole images, each segment was labeled as having normal perfusion, irreversible defects, or reversible defects. Using these classifications, concordance for the two methods was 92% (kappa = 0.87). MCE with HPDI is a safe and feasible method by which to detect asymptomatic ischemia due to severe stenotic lesion, and it may be an important addition to the modalities used to identify patients at risk for myocardial infarction as a complication of Kawasaki disease.

  17. Acute effect of oral flavonoid-rich dark chocolate intake on coronary circulation, as compared with non-flavonoid white chocolate, by transthoracic Doppler echocardiography in healthy adults.

    Science.gov (United States)

    Shiina, Yumi; Funabashi, Nobusada; Lee, Kwangho; Murayama, Taichi; Nakamura, Koki; Wakatsuki, Yu; Daimon, Masao; Komuro, Issei

    2009-01-24

    To assess the effects of the oral intake of flavonoid-rich dark chocolate on coronary circulation, we measured coronary flow velocity reserve (CFVR) by noninvasive transthoracic Doppler echocardiography (TTDE) in healthy adult subjects. The study was a randomized, single-blind design conducted for 2 weeks in 39 healthy men (mean age 29.7+/-3.9 years, range 23-40 years). Subjects were randomly assigned a daily intake of either flavonoid-rich dark chocolate (Meiji Black Chocolate 45 g, Meiji Seika kaisya Ltd, including cacao polyphenol 550 mg/day, 200 kcal) or non-flavonoid white chocolate (Meiji White Chocolate 35 g, Meiji Seika kaisya Ltd, including cacao polyphenol 0 mg/day, 140 kcal) as a control. CFVR was recorded by TTDE, and assessed before and after 2 weeks of intake. At the same time, we also assessed serum asymmetric dimethylarginine, 8-isoprostanes, and malondialdehyde-modified low-density lipoprotein (MDA-LDL) as markers of oxidative stress. Flavonoid-rich dark chocolate consumption significantly improved CFVR (3.38+/-0.49 before intake, 4.28+/-0.85 after intake; pchocolate consumption did not (3.28+/-0.49 before intake, 3.16+/-0.49 after intake; p=0.44). All predictor variables were used as dependent variables in a multiple regression model of the incremental change in CFVR after 2 weeks of chocolate intake. Intake of dark (but not white) chocolate, MDA-LDL, triglyceride (TG) and heart rate (HR) significantly influenced the change of CFVR after 2 weeks of intake (pchocolate intake, X1=intake of dark (but not white) chocolate, X2=MDA-LDL, X3=TG, X4=HR). Flavonoid-rich dark chocolate intake significantly improved coronary circulation in healthy adults, independent of changes in oxidative stress parameters, blood pressure and lipid profile, whereas non-flavonoid white chocolate had no such effects.

  18. Performance comparison of pulse-pair and wavelets methods for the pulse Doppler weather radar spectrum

    CERN Document Server

    Lagha, Mohand; Bergheul, Said; Rezoug, Tahar; Bettayeb, Maamar

    2012-01-01

    In the civilian aviation field, the radar detection of hazardous weather phenomena (winds) is very important. This detection will allow the avoidance of these phenomena and consequently will enhance the safety of flights. In this work, we have used the wavelets method to estimate the mean velocity of winds. The results showed that the application of this method is promising compared with the classical estimators (pulse-pair, Fourier).

  19. Transesophageal echocardiography assessment of severe ostial left main coronary stenosis

    Science.gov (United States)

    Firstenberg, M. S.; Greenberg, N. L.; Lin, S. S.; Garcia, M. J.; Alexander, L. A.; Thomas, J. D.

    2000-01-01

    Doppler echocardiography is commonly used in the assessment of stenotic valvular orifices. We describe the application of transesophageal echocardiography for the detection of a critical ostial left main coronary stenosis. Because preoperative coronary angiography often is not routinely performed in young patients undergoing valve surgery, application of Doppler echocardiography can potentially prevent catastrophic complications, particularly in atypical cases.

  20. Pulsed Compression for Aerosol Ranging with Coherent Pulse-Doppler Lidar Systems

    Science.gov (United States)

    1990-12-01

    generation technique requires an impulse function or short time duration pulse as the input to a dispersive phase filter . The frequency transfer...function H(f) of the dispersive phase filter can be expressed in general as H(f) = IH(f)Iexp lU(f)] (122) where the magnitude of the transfer function IH(f...response of the dispersive phase filter to a short time duration signal with large bandwidth B is a long time duration signal with the bandwidth B of

  1. Design and implementation of a smartphone-based portable ultrasound pulsed-wave Doppler device for blood flow measurement.

    Science.gov (United States)

    Huang, Chih-Chung; Lee, Po-Yang; Chen, Pay-Yu; Liu, Ting-Yu

    2012-01-01

    Blood flow measurement using Doppler ultrasound has become a useful tool for diagnosing cardiovascular diseases and as a physiological monitor. Recently, pocket-sized ultrasound scanners have been introduced for portable diagnosis. The present paper reports the implementation of a portable ultrasound pulsed-wave (PW) Doppler flowmeter using a smartphone. A 10-MHz ultrasonic surface transducer was designed for the dynamic monitoring of blood flow velocity. The directional baseband Doppler shift signals were obtained using a portable analog circuit system. After hardware processing, the Doppler signals were fed directly to a smartphone for Doppler spectrogram analysis and display in real time. To the best of our knowledge, this is the first report of the use of this system for medical ultrasound Doppler signal processing. A Couette flow phantom, consisting of two parallel disks with a 2-mm gap, was used to evaluate and calibrate the device. Doppler spectrograms of porcine blood flow were measured using this stand-alone portable device under the pulsatile condition. Subsequently, in vivo portable system verification was performed by measuring the arterial blood flow of a rat and comparing the results with the measurement from a commercial ultrasound duplex scanner. All of the results demonstrated the potential for using a smartphone as a novel embedded system for portable medical ultrasound applications. © 2012 IEEE

  2. Estimation of suspended sediment concentrations using Pulse-coherent Acoustic Doppler Profiler (PCADP)

    Institute of Scientific and Technical Information of China (English)

    BAI Xiufang; LI Siren; GONG Dejun; XU Yongping; JIANG Jingbo

    2009-01-01

    The objective of the study is to investigate the suitability of using Pulse-coherent Acoustic Doppler Profiler (PCADP) to estimate suspended sediment concentration (SSC). The acoustic backscatter intensity was corrected for spreading and absorption loss, then calibrated with OBS and finally converted to SSC. The results show that there is a good correlation between SSC and backscatter intensity with R value of 0.74. The mean relative error is 22.4%. Then the time span of little particle size variation was also analyzed to exclude the influence of size variation. The correlation coefficient increased to 0.81 and the error decreased to 18.9%. Our results suggest that the PCADP can meet the requirement of other professional instruments to estimate SSC with the errors between 20% and 50%, and can satisfy the need of dynamics study of suspended particles.

  3. Measurement of ultracold neutrons produced by using Doppler-shifted Bragg reflection at a pulsed-neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Brun, T.O.; Carpenter, J.M.; Krohn, V.E.; Ringo, G.R.; Cronin, J.W.; Dombeck, T.W.; Lynn, J.W.; Werner, S.A.

    1979-01-01

    Ultracold neutrons (UCN) have been produced at the Argonne pulsed-neutron source by the Doppler shift of 400-m/s neutrons Bragg reflected from a moving crystal. The peak density of UCN produced at the crystal exceeds 0.1 n/cm/sup 3/.

  4. 4-D flow magnetic resonance imaging: blood flow quantification compared to 2-D phase-contrast magnetic resonance imaging and Doppler echocardiography

    Energy Technology Data Exchange (ETDEWEB)

    Gabbour, Maya [Ann and Robert H. Lurie Children' s Hospital of Chicago, Department of Medical Imaging 9, Chicago, IL (United States); Schnell, Susanne [Northwestern University Feinberg School of Medicine, Department of Radiology, Chicago, IL (United States); Jarvis, Kelly [Northwestern University, Department of Biomedical Engineering, McCormick School of Engineering, Evanston, IL (United States); Robinson, Joshua D. [Ann and Robert H. Lurie Children' s Hospital of Chicago, Department of Pediatrics, Division of Pediatric Cardiology, Chicago, IL (United States); Northwestern University Feinberg School of Medicine, Department of Pediatrics, Chicago, IL (United States); Markl, Michael [Northwestern University Feinberg School of Medicine, Department of Radiology, Chicago, IL (United States); Northwestern University, Department of Biomedical Engineering, McCormick School of Engineering, Evanston, IL (United States); Rigsby, Cynthia K. [Ann and Robert H. Lurie Children' s Hospital of Chicago, Department of Medical Imaging 9, Chicago, IL (United States); Northwestern University Feinberg School of Medicine, Department of Radiology, Chicago, IL (United States)

    2015-06-15

    Doppler echocardiography (echo) is the reference standard for blood flow velocity analysis, and two-dimensional (2-D) phase-contrast magnetic resonance imaging (MRI) is considered the reference standard for quantitative blood flow assessment. However, both clinical standard-of-care techniques are limited by 2-D acquisitions and single-direction velocity encoding and may make them inadequate to assess the complex three-dimensional hemodynamics seen in congenital heart disease. Four-dimensional flow MRI (4-D flow) enables qualitative and quantitative analysis of complex blood flow in the heart and great arteries. The objectives of this study are to compare 4-D flow with 2-D phase-contrast MRI for quantification of aortic and pulmonary flow and to evaluate the advantage of 4-D flow-based volumetric flow analysis compared to 2-D phase-contrast MRI and echo for peak velocity assessment in children and young adults. Two-dimensional phase-contrast MRI of the aortic root, main pulmonary artery (MPA), and right and left pulmonary arteries (RPA, LPA) and 4-D flow with volumetric coverage of the aorta and pulmonary arteries were performed in 50 patients (mean age: 13.1 ± 6.4 years). Four-dimensional flow analyses included calculation of net flow and regurgitant fraction with 4-D flow analysis planes similarly positioned to 2-D planes. In addition, 4-D flow volumetric assessment of aortic root/ascending aorta and MPA peak velocities was performed and compared to 2-D phase-contrast MRI and echo. Excellent correlation and agreement were found between 2-D phase-contrast MRI and 4-D flow for net flow (r = 0.97, P < 0.001) and excellent correlation with good agreement was found for regurgitant fraction (r = 0.88, P < 0.001) in all vessels. Two-dimensional phase-contrast MRI significantly underestimated aortic (P = 0.032) and MPA (P < 0.001) peak velocities compared to echo, while volumetric 4-D flow analysis resulted in higher (aortic: P = 0.001) or similar (MPA: P = 0.98) peak

  5. Intracardiac echocardiography.

    Science.gov (United States)

    Bruce, C J; Friedman, P A

    2002-10-01

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

  6. Wind Profiling from a New Compact, Pulsed, 2-Micron, Coherent-Detection Doppler Lidar Transceiver during Wind Measurement Intercomparison

    Science.gov (United States)

    Singh, Upendra N.; Koch, Grady J.; Kavaya, Michael J.; Yu, Jirong; Beyon, Jeffrey Y.; Demoz, B.; Veneable, D.

    2009-01-01

    NASA Langley Research Center has a long history of developing 2-micron laser transmitter for wind sensing. With support from NASA Laser Risk Reduction Program (LRRP) and Instrument Incubator Program (IIP), NASA Langley Research Center has developed a state-of-the-art compact lidar transceiver for a pulsed coherent Doppler lidar system for wind measurement. This lidar system was recently deployed at Howard University facility in Beltsville, Maryland, along with other wind lidar systems. Coherent Doppler wind lidar ground-based wind measurements and comparisons with other lidars and other sensors will be presented.

  7. Pulsed Doppler Tissue Imaging for Assessment of Left Ventricular Systolic and Diastolic Synchronicity in Normal Subjects

    Institute of Scientific and Technical Information of China (English)

    Yang Li; Wu Wei; Wang Jingfeng; Zhang Xiaoling

    2006-01-01

    Objectives To quantitatively analyze the longitudinal myocardial systolic and diastolic velocities and time intervals of the left ventricle in normal subjects, and to explore the value of pulsed Doppler tissue imaging (DTI) for the assessment of left ventricular systolic and diastolic synchronicity.Methods Twenty and six healthy subjects were studied by pulsed DTI. The septal and lateral, anterior and inferior walls of the left ventricle were displayed respectively, and basal and middle segments of each wall were selected for myocardial motion spectrum sampling. DTI parameters were: peak systolic myocardial velocity (s), regional pre-ejection period (PEP), time to the peak of s wave (Ts), regional ejection time (ET); peak early diastolic velocity (e),peak late diastolic velocity (a), e/a ratio, time to the beginning of e wave (QE), time to the peak of e wave (Te) and regional isovolumic relaxation time (IVRT).Results The e and e/a were significantly different among basal segments, and s and e/a were significantly different among middle segments, with the highest value in lateral segments and the lowest value in septal segments. The s, e and a were all significantly higher in basal segments than middle segments. None of the systolic time intervals (PEP, Ts and ET) and diastolic time intervals (QE, Te and IVRT) were significantly different among basal segments and middle segments,neither were they when basal segment was compared with middle segment. Conclusions In normal subjects, the longitudinal myocardial systolic and diastolic velocities of the left ventricle are not homogeneous, but the contraction and relaxation are highly synchronized. Pulsed DTI can be used to quantitatively analyze the systolic and diastolic synchronicity of the heart.

  8. Accuracy of a pulse-coherent acoustic Doppler profiler in a wave-dominated flow

    Science.gov (United States)

    Lacy, J.R.; Sherwood, C.R.

    2004-01-01

    The accuracy of velocities measured by a pulse-coherent acoustic Doppler profiler (PCADP) in the bottom boundary layer of a wave-dominated inner-shelf environment is evaluated. The downward-looking PCADP measured velocities in eight 10-cm cells at 1 Hz. Velocities measured by the PCADP are compared to those measured by an acoustic Doppler velocimeter for wave orbital velocities up to 95 cm s-1 and currents up to 40 cm s-1. An algorithm for correcting ambiguity errors using the resolution velocities was developed. Instrument bias, measured as the average error in burst mean speed, is -0.4 cm s-1 (standard deviation = 0.8). The accuracy (root-mean-square error) of instantaneous velocities has a mean of 8.6 cm s-1 (standard deviation = 6.5) for eastward velocities (the predominant direction of waves), 6.5 cm s-1 (standard deviation = 4.4) for northward velocities, and 2.4 cm s-1 (standard deviation = 1.6) for vertical velocities. Both burst mean and root-mean-square errors are greater for bursts with ub ??? 50 cm s-1. Profiles of burst mean speeds from the bottom five cells were fit to logarithmic curves: 92% of bursts with mean speed ??? 5 cm s-1 have a correlation coefficient R2 > 0.96. In cells close to the transducer, instantaneous velocities are noisy, burst mean velocities are biased low, and bottom orbital velocities are biased high. With adequate blanking distances for both the profile and resolution velocities, the PCADP provides sufficient accuracy to measure velocities in the bottom boundary layer under moderately energetic inner-shelf conditions.

  9. Double mitral valve orifice. Two-dimensional and Doppler echocardiographic diagnosis.

    Science.gov (United States)

    Solorio, S; Badui, E; Yáñez, M; Enciso, R; Rodríguez, L; Quintero, L R

    1996-01-01

    The purpose of this study was to demonstrate the usefulness of two-dimensional and Doppler echocardiography for diagnosing double mitral valve orifices (DMVO) in addition to identifying associated pathologies. We report five cases, three male and two female with an age ranging from 4 to 44 years old (mean age: 17 years), with the diagnosis of DMVO according to the following characteristics: using two-dimensional echocardiography on the short parasternal axis, both orifices were observed; apical in which the "seagull sign" was identified in both chambers, in addition to identifying the flows of each orifice by pulsed and codified color Doppler obtaining the corresponding gradients. With respect to the associated pathologies, all patients presented some type of malformation, such as subaortic ring, patent ductus arteriosus, coarctation of the aorta, bicuspid aorta and pulmonary stenosis. Using the color Doppler echocardiography allows an adequate anatomical and functional definition of DMVO.

  10. Target detection in pulse-Doppler radar based on multi-scanning signal integration

    Directory of Open Access Journals (Sweden)

    O. S. Neuimin

    2013-07-01

    Full Text Available Introduction. Development of multi-scanning signal integration algorithms for pulseDoppler radars which are widely used in practice is of great practical importance. Problem statement. The problem of multi-scanning signal integration measuring range and range-rate is considered. The reflected signal from a target is a distorted white noise coherent packet of radio pulses with random initial phase and known amplitude. Target detection in a sequence of radar scans is reduced to the detection of target track. Development of a two-step multi-scanning incoherent signal integration algorithm. Two-step integration method is applied to reduce the number of tracks. In the first stage the initial signals detection with a sufficiently high probability of false alarm is performed. In the second stage the tracking problem for selection target markers is solved and the multiscanning signal integration is implemented. It provides an optimal target detection solution over K surveys with low signal-to-noise ratio. Expressions for the correct target detection probability and false alarm incorporating quality track tracking are obtained. Simulation results. Analysis of the algorithm is carried out as example of the little maneuvering target detection using the statistical modeling. The methods of calculating the output threshold (the cumulative statistics are compared on it is presented. Conclusions. Increasing the number of scans (in which the integration are performed leads to a significant decreasing the probability of false alarm, which allows to increase the signal-to-noise ratio compared with the detection in a single scan up to 3.5 dB.

  11. Comparison of NIRS, laser Doppler flowmetry, photoplethysmography, and pulse oximetry during vascular occlusion challenges.

    Science.gov (United States)

    Abay, T Y; Kyriacou, P A

    2016-04-01

    Monitoring changes in blood volume, blood flow, and oxygenation in tissues is of vital importance in fields such as reconstructive surgery and trauma medicine. Near infrared spectroscopy (NIRS), laser Doppler (LDF) flowmetry, photoplethysmography (PPG), and pulse oximetry (PO) contribute to such fields due to their safe and noninvasive nature. However, the techniques have been rarely investigated simultaneously or altogether. The aim of this study was to investigate all the techniques simultaneously on healthy subjects during vascular occlusion challenges. Sensors were attached on the forearm (NIRS and LDF) and fingers (PPG and PO) of 19 healthy volunteers. Different degrees of vascular occlusion were induced by inflating a pressure cuff on the upper arm. The responses of tissue oxygenation index (NIRS), tissue haemoglobin index (NIRS), flux (LDF), perfusion index (PPG), and arterial oxygen saturation (PO) have been recorded and analyzed. Moreover, the optical densities were calculated from slow varying dc PPG, in order to distinguish changes in venous blood volumes. The indexes showed significant changes (p  <  0.05) in almost all occlusions, either venous or over-systolic occlusions. However, differentiation between venous and arterial occlusion by LDF may be challenging and the perfusion index (PI) may not be adequate to indicate venous occlusions. Optical densities may be an additional tool to detect venous occlusions by PPG.

  12. High-frequency subharmonic pulsed-wave Doppler and color flow imaging of microbubble contrast agents.

    Science.gov (United States)

    Needles, A; Goertz, D E; Karshafian, R; Cherin, E; Brown, A S; Burns, P N; Foster, F S

    2008-07-01

    A recent study has shown the feasibility of subharmonic (SH) flow imaging at a transmit frequency of 20 MHz. This paper builds on these results by examining the performance of SH flow imaging as a function of transmit pressure. Further, we also investigate the feasibility of SH pulsed-wave Doppler (PWD) imaging. In vitro flow experiments were performed with a 1-mm-diameter wall-less vessel cryogel phantom using the ultrasound contrast agent Definity and an imaging frequency of 20 MHz. The phantom results show that there is an identifiable pressure range where accurate flow velocity and power estimates can be made with SH imaging at 10 MHz (SH10), above which velocity estimates are biased by radiation force effects and unstable bubble behavior, and below which velocity and power estimates are degraded by poor SNR. In vivo validation of SH PWD was performed in an arteriole of a rabbit ear, and blood velocity estimates compared well with fundamental (F20) mode PWD. The ability to suppress tissue signals using SH signals may enable the use of higher frame rates and improve sensitivity to microvascular flow or slow velocities near large vessel walls by reducing or eliminating the need for clutter filters.

  13. Comparison of pulsed wave and color Doppler myocardial velocity imaging in healthy dogs.

    Science.gov (United States)

    Wess, G; Killich, M; Hartmann, K

    2010-01-01

    Tissue velocity imaging (TVI) is increasingly used in small animal cardiology. Tissue velocity of the myocardial wall can be measured by pulsed wave (PW) or color Doppler (CD) imaging methods. Currently, the same reference ranges are used for PW TVI and CD TVI methods. However, if and how both methods correlate, and whether they can be used interchangeably, have not been assessed in small animals. To compare the results of PW TVI and CD TVI measurements. Seventy-one healthy dogs. Longitudinal myocardial velocity profiles were recorded from the 4-chamber left apical view. Peak maximal systolic (S), early (E), and late diastolic (A) velocities were measured off-line in a blinded fashion in the septal and lateral left ventricular wall by PW TVI and CD TVI. Differences between peak PW TVI and CD TVI waves were analyzed by a paired t-test. Regression analysis and Bland-Altman difference plots also were used to assess agreement between methods. There was a significant correlation between PW TVI and CD TVI (P Theses differences are clinically relevant. These methods should not be used interchangeably, and different reference ranges for PW TVI and CD TVI should be used.

  14. Origination of gamma-ray burst pulses associated with the Doppler effect of spherical fireballs or uniform jet

    Institute of Scientific and Technical Information of China (English)

    Lu Rui-Jing; Qin Yi-Ping; Zhang Fu-Wen

    2007-01-01

    Ryde and Petrosian have pointed out that the rise phases of gamma-ray burst (GRB) pulses originate from the widths of the intrinsic pulses and their decay phases are determined by the curvature effect of the expanding fireball surface based on their simplified formula. In this paper we investigate in detail the issue based on the formula in Ref.[20], which is derived based on a model of highly symmetric expanding fireballs, where the Doppler effect is the key factor to be concerned about, and no terms are omitted in their derivation. Our analyses show that the decay phases of the observed pulses originate from the contributions from both the curvature effect of the expanding fireball and the two timescales of the local pulses, and the rise phases of the observed pulses only come from the two timescales of the local pulses. Associated with a local pulse with both rise and decay portions, the light curve of GRBs in the rise portion is expected to undergo a concave phase and then a convex one, whereas that in the decay portion is expected to evolve by an opposite process. And the ratio of the concave timescale to the convex one in the rise phase of the observed pulse linearly increases with the ratio of the rising timescale to the decay one of the local pulse (γrd), whereas the ratio of the convex timescale to the concave timescale in its decay phase linearly decreases with γrd. The two correlations are independent of the local pulse forms and the rest-frame radiation forms. But the different forms of local pulses and the different values of γrd gives rise to the diversity of the light curve pulse shapes. We test a sample of 86 GRB pulses detected by the BATSE instrument on board the Compton Gamma Ray Observatory and find that the characteristics do exist in the light curve of GRBs.

  15. Effects of chronic severe pulmonary regurgitation and percutaneous valve repair on right ventricular geometry and contractility assessed by tissue Doppler echocardiography

    DEFF Research Database (Denmark)

    Kjaergaard, Jesper; Iversen, Kasper K; Vejlstrup, Niels G;

    2010-01-01

    Pulmonary regurgitation (PR) following repair of right ventricular (RV) outflow obstruction is related to slowly progressive RV dilatation and heart failure and will eventually require surgical intervention, but optimal timing of pulmonary valve replacement is challenging. Tissue Doppler based...

  16. Applications of pulsed Doppler flow mapping to left sided cardiac valvular lesions.

    Science.gov (United States)

    Kalmanson, D; Veyrat, C; Gourtchiglouian, C; Bas, S; Abitbol, G

    The flow mapping procedure has been developed in parallel to the standard pulsed Doppler procedure. It has a different purpose--picking up flow signals at the site of lesions rather than calibrating velocities--and has its own methodology, developed within the last six years. On the basis of invasive correlations performed in 267 cases of valvular heart disease, we review the three-fold purpose of the flow mapping technique: diagnosing lesions, relying on the presence of flow anomalies; assessing their severity, relying on the spatial spreading of these flow signals; and identifying the site of the lesion, which is a specific advantage, relying on the anatomical location of these flow signals and/or on the direction of the jets. For example, using this technique, it is now possible to easily differentiate a cusp tear from a leak of a bioprosthesis, to measure the size of the leaks, and to reconstruct the image of aortic or mitral stenotic areas. These optimal results are only obtained using an appropriate methodology which mainly includes a) the selection of adequate two-dimensional short axis planes in order to explore the diseased valve in its entirety, because of frequent assymetrical orifices, and to pick up the jets at their starting point, b) measurements of the abnormal areas, c) when jets are studied, a three dimensional approach is required in order to cope with the three dimensional nature of the jet and to make available the calculation of three dimensional indices of severity.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Ultrasonic position and velocity measurement for a moving object by M-sequence pulse compression using Doppler velocity estimation by spectrum-pattern analysis

    Science.gov (United States)

    Ikari, Yohei; Hirata, Shinnosuke; Hachiya, Hiroyuki

    2015-07-01

    Pulse compression using a maximum-length sequence (M-sequence) can improve the signal-to-noise ratio (SNR) of the reflected echo in the pulse-echo method. In the case of a moving object, however, the echo is modulated owing to the Doppler effect. The Doppler-shifted M-sequence-modulated signal cannot be correlated with the reference signal that corresponds to the transmitted M-sequence-modulated signal. Therefore, Doppler velocity estimation by spectrum-pattern analysis of a cyclic M-sequence-modulated signal and cross correlations with Doppler-shifted reference signals that correspond to the estimated Doppler velocities has been proposed. In this paper, measurements of the position and velocity of a moving object by the proposed method are described. First, Doppler velocities of the object are estimated using a microphone array. Secondly, the received signal from each microphone is correlated with each Doppler-shifted reference signal. Then, the position of the object is determined from the B-mode image formed from all cross-correlation functions. After that, the velocity of the object is calculated from velocity components estimated from the Doppler velocities and the position. Finally, the estimated Doppler velocities, determined positions, and calculated velocities are evaluated.

  18. Diagnose value of bedside color doppler echocardiography to children in neonatal intensive care unit%床旁彩色多普勒超声心动图对NICU患儿的诊断价值

    Institute of Scientific and Technical Information of China (English)

    冯俊; 常凤玲

    2011-01-01

    目的:探讨床旁彩色多普勒超声心动图在新生儿重症监护室(NICU)中的应用价值.方法:选取2008年1月~2010年5月使用美国GE-vivid-i便携式床旁彩超诊断仪对NICU新生儿中临床疑似先天性心脏病(CHD)的341例患儿进行心脏彩超检查,采用胸骨旁、剑突下、心尖及胸骨上窝等多切面反复探查,CHD按心脏三级顺序分段法检查并作出诊断.结果:床旁超声心动图检出CHD患儿256例,其中非紫绀型先天性心脏病96例,紫绀型先天性心脏病82例,卵圆孔未闭31例,动脉导管未闭26例,二者并存12 例,瓣膜反流2例,假腱索7例.NICU多为早产儿及新生儿,较为常见的心内分流为卵圆孔未闭,其与动脉导管未闭在未来均有闭合的可能,不诊断为先天性心脏病.结论:床旁彩色多普勒超声心动图可为患儿提供可靠的诊断信息,为进一步检查和治疗提供可靠依据.%Objective: To investigate the application value of bedside color doppler echocardiography in neonatal intensive care unit (NICLJ). Methods: 341 neonates in NICLJ suspected with congenital heart disease (CHD) were received color echocardiography examination with the American GE-vivid-I portable bedside color echocardiography from August 2008 to May 2010 by repeated search from multiple sections such as parasternum, infraxiphoid, apex cordis and suprasternal fossa. The CHD was examined and diagnosed by the heart tertiary sequence sectioning method. Results: 256 children were diagnosed with CHD by bedside color doppler echocardiography detection, 96 children were non-cyanotic and 82 children were cyaotic. 31 children were patent foramen ovale, 26 patent ductus arteriosus, 12 both, 2 valvular regurgitation and 7 false chordae tendineae. Children in the NICLJ were mostly premature infants and neonates, for who the more common intracardiac shunt was patent foramen ovale. Patent foramen ovale and patent ductus arteriosus were likely to close in the future

  19. Analytical and experimental comparisons between the frequency-modulated–frequency-shift measurement and the pulsed-wave–time-shift measurement Doppler systems

    DEFF Research Database (Denmark)

    Wilhjelm, Jens Erik; Pedersen, P. C.

    1996-01-01

    In previous publications, a new echo-ranging Doppler system based on transmission of repetitive coherent frequency modulated (FM) sinusoids in two different implementations was presented. One of these implementations, the Frequency Modulated - frequency shift measurement (FM-fsm) Doppler system...... is in this paper compared with its PW counterpart, the Pulsed Wave - time shift measurement (PW-tsm) Doppler system. When using transmitted PW and FM signals with a Gaussian envelope, the parallelism between the two systems can be stated explicitly, and comparison be made between the main performance indices...... for the two Doppler systems. The performance of the FM and PW Doppler systems is evaluated by means of numerical simulation and measurements of actual flow profiles. The results indicate that the two Doppler systems have very similar levels of performance....

  20. Estimation of diastolic filling pressure with cardiac CT in comparison with echocardiography using tissue doppler imaging: Determination of optimal CT reconstruction parameters

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Ji Sun; Suh, Jon; Lee, Heon [Soonchunhyang University Hospital Bucheon, Bucheon (Korea, Republic of); Lee, Bora [Dept. of Biostatistics, Soonchunhyang University College of Medicine, Seoul (Korea, Republic of); Lee, Soo Jeong [Terarecon Korea, Seoul (Korea, Republic of); Jou, Sung Shick [Dept. of Radiology, Soonchunhyang University Hospital Cheonan, Cheonan (Korea, Republic of); Lim, Hyun Kyung [Dept. of Radiology, Soonchunhyang University Hospital Seoul, Seoul (Korea, Republic of)

    2017-08-01

    To determine the optimal CT image reconstruction parameters for the measurement of early transmitral peak velocity (E), early peak mitral septal tissue velocity (E′), and E / E′. Forty-six patients underwent simultaneous cardiac CT and echocardiography on the same day. Four CT datasets were reconstructed with a slice thickness/interval of 0.9/0.9 mm or 3/3 mm at 10 (10% RR-interval) or 20 (5% RR-interval) RR-intervals. The E was calculated by dividing the peak transmitral flow (mL/s) by the corresponding mitral valve area (cm{sup 2}). E′ was calculated from the changes in the left ventricular length per cardiac phase. E / E′ was then estimated and compared with that from echocardiography. For assessment of E / E′, CT and echocardiography were more strongly correlated (p < 0.05) with a slice thickness of 0.9 mm and 5% RR-interval (r = 0.77) than with 3 mm or 10% RR-interval. The diagnostic accuracy of predicting elevated filling pressure (E / E′ ≥ 13, n = 14) was better with a slice thickness of 0.9 mm and 5% RR-interval (87.0%) than with 0.9 mm and 10% RR-interval (71.7%) (p = 0.123) and significantly higher than that with a slice thickness of 3 mm with 5% (67.4%) and 10% RR-interval (63.0%), (p < 0.05), respectively. Data reconstruction with a slice thickness of 0.9 mm at 5% RR-interval is superior to that with a slice thickness of 3 mm or 10% RR-interval in terms of the correlation of E / E′ between CT and echocardiography. Thin slices and frequent sampling also allow for more accurate prediction of elevated filling pressure.

  1. Airborne wind profiling algorithms for the pulsed 2-micron coherent doppler Lidar at NASA Langley Research Center

    Science.gov (United States)

    Beyon, Jeffrey Y.; Koch, Grady J.; Kavaya, Michael J.; Ray, Taylor J.

    2013-05-01

    Two versions of airborne wind profiling algorithms for the pulsed 2-micron coherent Doppler lidar system at NASA Langley Research Center in Virginia are presented. Each algorithm utilizes different number of line-of-sight (LOS) lidar returns while compensating the adverse effects of different coordinate systems between the aircraft and the Earth. One of the two algorithms APOLO (Airborne Wind Profiling Algorithm for Doppler Wind Lidar) estimates wind products using two LOSs. The other algorithm utilizes five LOSs. The airborne lidar data were acquired during the NASA's Genesis and Rapid Intensification Processes (GRIP) campaign in 2010. The wind profile products from the two algorithms are compared with the dropsonde data to validate their results.

  2. Pulsed-wave tissue Doppler and color tissue Doppler echocardiography: calibration with M-mode, agreement, and reproducibility in a clinical setting

    DEFF Research Database (Denmark)

    Olsen, Niels Thue; Jons, Christian; Fritz-Hansen, Thomas

    2009-01-01

    of the two methods in a routine clinical setting. METHODS: For Study A, the displacements of 63 basal myocardial segments from 13 patients were examined with M-mode and compared with the velocity-time integral of PWTD and CTD velocities. For Study B, the basal lateral segments from 58 patients were examined...... 2.29 +/- 1.82 cm/sec; P numerically smaller tissue velocities than PWTD, mostly due to an overestimation of true tissue motion by PWTD...

  3. Pulsed Doppler echocardiographic evaluation of the blood stream in children with morphological heart lesion

    NARCIS (Netherlands)

    J.C. Areias (José)

    1982-01-01

    textabstractEchocardiography is well estabished as a valuable method for detecting specific lesions and is useful for obtaining information which is helpful in the management of many patients with congenital and acquired abnormalities of the heart and great vessels (1-9). However, conventional M-mod

  4. Noise and Speckle Reduction in Doppler Blood Flow Spectrograms Using an Adaptive Pulse-Coupled Neural Network

    Directory of Open Access Journals (Sweden)

    Haiyan Li

    2010-01-01

    Full Text Available A novel method, called adaptive pulse coupled neural network (AD-PCNN using a two-stage denoising strategy, is proposed to reduce noise and speckle in the spectrograms of Doppler blood flow signals. AD-PCNN contains an adaptive thresholding PCNN and a threshold decaying PCNN. Firstly, PCNN pulses based on the adaptive threshold filter a part of background noise in the spectrogram while isolating the remained noise and speckles. Subsequently, the speckles and noise of the denoised spectrogram are detected by the pulses generated through the threshold decaying PCNN and then are iteratively removed by the intensity variation to speckle or noise neurons. The relative root mean square (RRMS error of the maximum frequency extracted from the AD-PCNN spectrogram of the simulated Doppler blood flow signals is decreased 25.2% on average compared to that extracted from the MPWD (matching pursuit with Wigner Distribution spectrogram, and the RRMS error of the AD-PCNN spectrogram is decreased 10.8% on average compared to MPWD spectrogram. Experimental results of synthetic and clinical signals show that the proposed method is better than the MPWD in improving the accuracy of the spectrograms and their maximum frequency curves.

  5. Efficient cloning and dragging of microwave pulse into optical frequency pulse in a Doppler-broadened atomic medium

    CERN Document Server

    V., Rajitha K

    2015-01-01

    The propagation of a weak optical pulse through an atomic system in closed $\\Lambda$ configuration is investigated in which the hyper fine levels are coupled by a microwave pulse. Under three photon resonance condition, it is observed that the probe pulse shape gets cloned by the shape of the microwave pulse along propagation through the medium. The temporal position of the probe pulse is dragged to that of the microwave pulse. A simple expression for the linear susceptibility of the medium for the corresponding transition is derived in the Fourier domain. From the numerical analysis of dynamics using this expression, it is concluded that the novel effect arises from the ground state coherence of the hyper fine transitions induced by the microwave pulse.

  6. Ecocardiografia-doppler e parâmetros hemodinâmicos em cardiopatias congênitas com hiperfluxo pulmonar Ecocardiografia-doppler y parámetros hemodinámicos en cardiopatías congénitas con hiperflujo pulmonar Doppler echocardiography and hemodynamic parameters in congenital heart disease with increased pulmonary flow

    Directory of Open Access Journals (Sweden)

    Zilma Verçosa de Sá Ribeiro

    2010-05-01

    áficos relacionados al flujo sistólico pulmonar y sistémico y al flujo en la vena pulmonar fueron relacionados a datos hemodinámicos en 30 pacientes consecutivos con defectos septales cardíacos (edad entre 4 meses y 58 años, mediana 2,2 años; presión arterial pulmonar media entre 16 y 93 mmHg. RESULTADOS: Las variables integral velocidad-tiempo del flujo sistólico en la vía de salida del ventrículo derecho (VTIVSVD > 22 cm y del flujo en la vena pulmonar (VTIVP > 20 cm fueron predictivas de niveles RVP/RVS 27 cm y VTIVP > 24 cm, la especificidad fue superior a 0,90 y la razón de chances 2,29 y 4,47 respectivamente. La razón entre los flujos pulmonar y sistémico (Qp/Qs > 2,89 y > 4,0, estimaciones ecocardiográficas fue útil para la predicción de valores Qp/Qs > 3,0 por cateterismo (especificidad de 0,78 y 0,91, razón de chances 1,14 y 2,97, respectivamente. CONCLUSIÓN: En portadores de defectos septales cardíacos, la ecocardiografía-Doppler es capaz de identificar aquellos en situación de aumento de flujo y bajos niveles de resistencia vascular pulmonar.BACKGROUND: The prediction of pulmonary hemodynamic data from non-invasive assessment could exempt some patients with congenital cardiac septal defects from preoperative invasive assessment (catheterization. OBJECTIVE: To determine, in simultaneous assessment, whether data obtained from Doppler echocardiography could predict aspects of pulmonary hemodynamics in such patients. METHODS: Echocardiographic parameters related to systolic and systemic pulmonary flow and pulmonary venous flow were related to hemodynamic data in 30 consecutive patients with cardiac septal defects (aged 4 months to 58 years, median 2.2 years, mean pulmonary artery pressure between 16 and 93 mmHg. RESULTS: The velocity-time integrals of systolic flow in right ventricle outflow tract (VTI RVOT > 22 cm and pulmonary venous flow (VTI VP > 20 cm predicted PVR/SVR 27 cm and VTI PV > 24 cm values, the specificity was higher than 0.90 and odds

  7. Pulsed Doppler echocardiographic evaluation of the blood stream in children with morphological heart lesion

    OpenAIRE

    Areias, José

    1982-01-01

    textabstractEchocardiography is well estabished as a valuable method for detecting specific lesions and is useful for obtaining information which is helpful in the management of many patients with congenital and acquired abnormalities of the heart and great vessels (1-9). However, conventional M-mode and two-dimensional echocardiographic techniques are not always diagnostic since some acquired and congenital cardiac disorders result in nonspecific echocardiographic findings (10-11). Range gat...

  8. Pulsed and Color Doppler Sonographic Findings of Penile Mondor' Disease

    Energy Technology Data Exchange (ETDEWEB)

    Han, Hye Yeon; Chung, Dong Jin; Kim, Kum Won; Hwang, Cheol Mog [University of Konyang School of Medicine, Daejeon (Korea, Republic of)

    2008-04-15

    Penile Mondor's disease is a rare disease that's characterized by thrombosis in the dorsal vein of the penis. Doppler ultrasonography (US) clearly visualizes dorsal vein thrombosis and the associated hemodynamic alterations. Previous studies have demonstrated the typical color Doppler US findings of superficial dorsal vein thrombosis without the flow signals in this area, yet this is insufficient to understand the hemodynamics in penile Mondor's disease. We report here for the first time a cavernosal artery flow signal pattern in a penile Mondor's disease patient, in addition to its previously reported classic US findings. In conclusion, the Doppler US findings of thrombus without blood flow in the superficial dorsal vein and the low-flow, high resistance in the cavernosal artery may be suggestive of penile Mondor's disease.

  9. [Stress echocardiography: development and significance].

    Science.gov (United States)

    Attenhofer, C; Ritter, M; Jenni, R

    1994-08-27

    Exercise electrocardiography is still the primary method used in the non-invasive assessment of coronary artery disease. Stress echocardiography is now being increasingly used as a more sensitive adjunct technique to assess ischemia. Ischemia provoked by stress can induce reversible wall motion abnormalities which are disclosed by cross-sectional 2-dimensional echocardiography and standard projections. The types of stress used are physical exercise (bicycle, treadmill), atrial pacing or pharmacologic stimulation. In the latter, the catecholamine dobutamine has emerged as preferable to the vasodilators dipyridamole and adenosine. The diagnostic accuracy of dobutamine stress echocardiography is comparable to that of bicycle or treadmill exercise echocardiography, but dobutamine stress echocardiography is technically simpler and can be performed in patients unable to exercise. Its sensitivity in diagnosing ischemic or viable myocardium is comparable to that of nuclear methods, MRI or PET. In contrast to nuclear methods, stress echocardiography is however free of radiation. In the assessment of patients with coronary artery disease, stress echocardiography has been shown to be valuable for diagnosis, preoperative risk stratification and determination of prognosis. Furthermore, low dose dobutamine echocardiography can be used to detect viable myocardium. Despite these very promising aspects of the method, there are recognized disadvantages and limitations: stress echocardiography is very time-consuming and operator-dependent; its sensitivity correlates strongly with the number of studies performed; analysis of wall motion is performed qualitatively on a purely subjective level, and hence lacks the objectivity of a quantitative approach. These factors emphasize the need for intensive research to render stress echocardiographic analysis more objective. Automatic boundary detection of left ventricular endocardium, color-Doppler-based tissue imaging and three

  10. Study of the Myocardial Contraction and Relaxation Velocities through Doppler Tissue Imaging Echocardiography: A New Alternative in the Assessment of the Segmental Ventricular Function

    Directory of Open Access Journals (Sweden)

    Silva Carlos Eduardo Suaide

    2002-01-01

    Full Text Available OBJECTIVE: Doppler tissue imaging (DTI enables the study of the velocity of contraction and relaxation of myocardial segments. We established standards for the peak velocity of the different myocardial segments of the left ventricle in systole and diastole, and correlated them with the electrocardiogram. METHODS: We studied 35 healthy individuals (27 were male with ages ranging from 12 to 59 years (32.9 ± 10.6. Systolic and diastolic peak velocities were assessed by Doppler tissue imaging in 12 segments of the left ventricle, establishing their mean values and the temporal correlation with the cardiac cycle. RESULTS: The means (and standard deviation of the peak velocities in the basal, medial, and apical regions (of the septal, anterior, lateral, and posterior left ventricle walls were respectively, in cm/s, 7.35(1.64, 5.26(1.88, and 3.33(1.58 in systole and 10.56(2.34, 7.92(2.37, and 3.98(1.64 in diastole. The mean time in which systolic peak velocity was recorded was 131.59ms (±19.12ms, and diastolic was 459.18ms (±18.13ms based on the peak of the R wave of the electrocardiogram. CONCLUSION: In healthy individuals, maximum left ventricle segment velocities decreased from the bases to the ventricular apex, with certain proportionality between contraction and relaxation (P<0.05. The use of Doppler tissue imaging may be very helpful in detecting early alterations in ventricular contraction and relaxation.

  11. Usefulness of color and pulsed Doppler's in the evaluation of surgical portosystemic shunts in pediatric patients; Utilidad del Doppler color y pulsado en la valoracion de los shunts portosistemicos quirurgicos en la edad pediatrica

    Energy Technology Data Exchange (ETDEWEB)

    Berrocal, T.; Prieto, C.; Cortes, P.; Rodriguez, R.; Pastor, I. [Hospital Universitario La Paz. Madrid (Spain)

    2003-07-01

    Portosystemic shunts are performed to relieve symptomatic portal hypertension symptomatic or removal pressure in hepatic vascularisation in patients with Budd-Chiari's syndrome. Most surgical portosystemic shunts can be suitably studied by means of ultrasound scan complemented by color and pulsed Dopplers, proved one understands the hemodynamics of the surgical procedures involved. This article demonstrates the usefulness and limitations of the ultrasound scan Duplex Doppler in the evaluation of portosystemic shunts performed on pediatric patients. Pulsed Doppler provides information regarding the nature and direction of blood flow. Color doppler is capable of directly revealing the shunt and, in most cases, permits the anastomosis to be located. The types of shunts that appear include proximal and distal spleno-renal, portocaval and mesocaval. Types of vascular connections are illustrated,s well as expected post-surgical blood flow direction in affected vessels. The ultrasound scanning technique is discussed, as well as the criteria for determining vascular permeability. Also highlighted are the advantages, limitations and diagnostic difficulties associated with the different forms of Doppler. (Author) 17 refs.

  12. Sizing of Emboli in Flowing Blood Using Pulse Doppler Ultrasound and the Embolus-To Power Ratio.

    Science.gov (United States)

    Moehring, Mark Alan

    The embolus to blood ratio (EBR) theoretical model describing pulse Doppler ultrasound observations of emboli in flowing blood is summarized. The EBR model uses the backscattered signal power from blood in the Doppler sample volume as a reference from which to assess embolus size and composition. This EBR is independent of attenuation and reflection loss in intervening tissues between probe and bloodflow. An in vitro investigation is presented that tests the validity of the EBR model. The experimental apparatus includes a novel phantom for Doppler observation of circulating emboli and a Doppler system which uses 1.6 and 2.4 MHz concurrently for interrogation of an embolus. The phantom contains a tubeless flow conduit inside a polyacrylamide gel and a blood-mimicking fluid flowing in the conduit. Time series Doppler shift data which are gathered while polystyrene microsphere "emboli" transit the sample volume are post -processed to calculate the EBR on each embolic signature. EBR measurements from microspheres of three different diameters are summarized and shown to contain pronounced and systematic variability. The hypothesis is presented that this variability is due to a small speed of sound mismatch between the gel and the blood-mimicking fluid, a phenomenon anticipated in vivo. This speed of sound mismatch results in beam refraction and a non-uniformly insonated sample volume (thereby causing variability in embolus signatures). A three dimensional theoretical study is presented that models beam refraction resulting from speed of sound mismatch between the blood mimicking fluid and the surrounding gel. A Monte Carlo study of the EBR behavior in the presence of beam refraction is performed and yields similar results to the data obtained in vitro. This study is evidence that the experimental signal variability is due to speed of sound mismatch between blood-mimicking fluid and gel. A method of extracting embolus size from the dual frequency EBR data based on the

  13. Pulsed-wave tissue Doppler imaging of the myocardium of cats with induced thyrotoxicosis Doppler tecidual pulsado do miocárdio de gatos com tirotoxicose induzida

    Directory of Open Access Journals (Sweden)

    Daniel Capucho de Oliveira

    2011-06-01

    Full Text Available Left ventricular myocardial motion was quantified using pulsed-wave tissue Doppler imaging (PW-TDI in nine adult cats before and after thyrotoxicosis induction. In order to induce thyrotoxicosis, all cats were given 150µg kg-1 of levothyroxine sodium as a single oral dose each day for 10 weeks. PW-TDI examinations were performed immediately before the induction and by the end of the experimental protocol. An increase in myocardial motion velocity was documented at the interventricular septum level, demonstrated by an elevation in systolic (Sa, and early (Ea and late (Aa diastolic waves (PA velocidade de movimentação miocárdica do ventrículo esquerdo foi quantificada por meio de exames ecocardiográficos com Doppler tecidual pulsado (PW-TDI em nove gatos adultos antes e após indução à tirotoxicose. Para indução da tirotoxicose, todos os gatos receberam doses diárias de 150mg kg-1 de levotiroxina sódica, por via oral, durante 10 semanas. Os exames de PW-TDI foram realizados imediatamente antes da indução e ao final do protocolo experimental. Uma elevação na velocidade de movimentação miocárdica foi documentada ao nível do septo interventricular, demonstrado por um aumento das ondas sistólica (Sa e diastólicas (Ea e Aa; P<0,05. No entanto, nenhuma alteração nos valores de Sa, Ea e Aa foi encontrada ao nível da parede livre do ventrículo esquerdo. A frequência cardíaca aumentou significativamente entre os momentos experimentais, sendo que três animais apresentaram fusão das ondas Aa e Ea ao final do experimento. O protocolo experimental utilizado neste estudo causou alterações na velocidade de movimentação do miocárdio ventricular esquerdo, mas sem causar danos à função diastólica do ventrículo esquerdo.

  14. Photoacoustic & pulsed laser-doppler monitoring of blood concentration and perfusion in tissue

    OpenAIRE

    Kolkman, Roy Gerardus Maria

    2002-01-01

    In medicine there are situations that require continuous bedside monitoring of perfusion and blood volume. Such a situation can occur when children are born prematurely. Those children have a high risk to develop a handicap, which is most likely caused by cerebral damage due to impaired brain perfusion. Monitoring cerebral perfusion can provide information for preventive treatment. In this thesis we have explored the potential of photoacoustics and laser Doppler flowmetry for measurement of c...

  15. Stress echocardiography

    NARCIS (Netherlands)

    A. Salustri (Alessandro)

    1993-01-01

    textabstractIn the studies reported in this thesis, stress echocardiography (either with exercise or with pharmacological agents) and myocardial perfusion scintigraphy have been performed in different groups of patients and in different clinical conditions. Some practical aspects on the protocols of

  16. Stress echocardiography

    NARCIS (Netherlands)

    A. Salustri (Alessandro)

    1993-01-01

    textabstractIn the studies reported in this thesis, stress echocardiography (either with exercise or with pharmacological agents) and myocardial perfusion scintigraphy have been performed in different groups of patients and in different clinical conditions. Some practical aspects on the protocols

  17. Stress Doppler echocardiography in relatives of patients with idiopathic and familial pulmonary arterial hypertension: results of a multicenter European analysis of pulmonary artery pressure response to exercise and hypoxia.

    Science.gov (United States)

    Grünig, Ekkehard; Weissmann, Sylvia; Ehlken, Nicola; Fijalkowska, Anna; Fischer, Christine; Fourme, Thierry; Galié, Nazzareno; Ghofrani, Ardeschir; Harrison, Rachel E; Huez, Sandrine; Humbert, Marc; Janssen, Bart; Kober, Jaroslaw; Koehler, Rolf; Machado, Rajiv D; Mereles, Derliz; Naeije, Robert; Olschewski, Horst; Provencher, Steeve; Reichenberger, Frank; Retailleau, Kathleen; Rocchi, Guido; Simonneau, Gérald; Torbicki, Adam; Trembath, Richard; Seeger, Werner

    2009-04-07

    This large, prospective, multicentric study was performed to analyze the distribution of tricuspid regurgitation velocity (TRV) values during exercise and hypoxia in relatives of patients with idiopathic and familial pulmonary arterial hypertension (PAH) and in healthy control subjects. We tested the hypothesis that relatives of idiopathic/familial PAH patients display an enhanced frequency of hypertensive TRV response to stress and that this response is associated with mutations in the bone morphogenetic protein receptor II (BMPR2) gene. TRV was estimated by Doppler echocardiography during supine bicycle exercise in normoxia and during 120 minutes of normobaric hypoxia (FIO(2)=12%; approximately 4500 m) in 291 relatives of 109 PAH patients and in 191 age-matched control subjects. Mean maximal TRVs were significantly higher in PAH relatives during both exercise and hypoxia. During exercise, 10% of control subjects but 31.6% of relatives (Ppressure, smoking status, or heart rate. Within kindreds identified as harboring deleterious mutations of the BMPR2 gene, a hypertensive TRV response occurred significantly more often compared with those without detected mutations. Pulmonary hypertensive response to exercise and hypoxia in idiopathic/familial PAH relatives appears as a genetic trait with familial clustering, being correlated to but not caused by a BMPR2 mutation. The suitability of this trait to predict manifest PAH development should be addressed in long-term follow-up studies.

  18. [Coronary artery blood flow velocity non-invasively measured using a vessel-tracking pulsed Doppler system].

    Science.gov (United States)

    Tateishi, O; Aizawa, O; Okamura, T; Yoshida, T; Furuhata, H; Seo, Y; Iinuma, K; Shiki, E

    1988-09-01

    A newly-developed noninvasive method was used to measure left coronary blood flow during phantom experiments. Two techniques were used in which: (1) the sample position can always be set in a fluctuating vessel using a wall echo-tracking method with a phase-locked-loop, and (2) the Doppler reference signal was generated separately synchronous with the wall echo signal. These techniques were combined, using a commercially available pulsed Doppler apparatus (SSH-40B: Toshiba). Basic experiments were performed using a blood vessel phantom to verify the validity of these systems. Blood flow velocity in the fluctuating tube could be measured clearly using a vessel-tracking method. The blood flow velocity of the left anterior descending artery was measured in three normal subjects and in seven patients from the third intercostal space along the left sternal border. The velocity pattern was characterized by a crescendo-decrescendo shape in diastole. The peak velocity which appeared in diastole ranged from 19 to 69 cm/sec, with no difference by disease entity. However, in all cases, the blood flow velocity signals were marred by extraneous signals, making it impossible to measure blood flow velocity during systole. Further improvement of the system is mandatory in order to use this flowmeter clinically.

  19. Recalculation of an artificially released avalanche with SAMOS and validation with measurements from a pulsed Doppler radar

    Directory of Open Access Journals (Sweden)

    R. Sailer

    2002-01-01

    Full Text Available A joint experiment was carried out on 10 February 1999 by the Swiss Federal Institute for Snow and Avalanche Research (SFISAR and the Austrian Institute for Avalanche and Torrent Research (AIATR, of the Federal Office and Re-search Centre for Forests, BFW to measure forces and velocities at the full scale experimental site CRÊTA BESSE in VALLÉE DE LA SIONNE, Canton du Valais, Switzerland. A huge avalanche could be released artificially, which permitted extensive investigations (dynamic measurements, im-provement of measurement systems, simulation model verification, design of protective measures, etc.. The results of the velocity measurements from the dual frequency pulsed Doppler avalanche radar of the AIATR and the recalculation with the numerical simulation model SAMOS are explained in this paper.

  20. Hemodynamics in the portal vein evaluated by pulse wave Doppler ultrasonography in patients with chronic hepatitis C treated with interferon

    Institute of Scientific and Technical Information of China (English)

    Shigeo Nakanishi; Katsuya Shiraki; Kouji Yamamoto; Mutsumi Koyama; Noboru Kimura; Takeshi Nakano

    2005-01-01

    AIM: To employ pulse wave Doppler ultrasonography to evaluate the changes in portal blood flow velocity in patients with chronic hepatitis C (CHC) receiving interferon (IFN)treatment.METHODS: The subjects in this study were 14 patients (13 men and 1 woman) with CHC who received IFN treatment. Portal blood flow velocity was measured in the vessels at the porta hepatis at four time points: before IFN administration (pre-IFN), 2 wk after the start of administration (wk 2), 24 wk after the start of administration (wk 24, i.e.,the end of IFN administration), and 24 wk after the end of administration (wk 48).RESULTS: The patients with CHC in whom IFN treatment resulted in complete elimination or effective elimination of viruses showed a significant increase in portal blood flow velocity at the end of IFN treatment compared with that before IFN treatment. In contrast, when IFN was ineffective, no significant increase in portal bloocl flow velocity was observed at wk 24 or 48 compared with the pre-IFN value. In addition,the patients with CHC in whom IFN was ineffective showed significantly lower portal blood flow velocity values than control subjects at all measurement time points.CONCLUSION: Pulse wave Doppler ultrasonography is a noninvasive and easily performed method for evaluating the effects of IFN treatment in patients with CHC. This technique is useful for measuring portal blood flow velocity before and 24 wk after IFN administration in order to evaluate the changes over time, thus assessing the effectiveness of IFN treatment.

  1. Spectral pulsed-wave tissue Doppler imaging lateral-to-septal delay fails to predict clinical or echocardiographic outcome after cardiac resynchronization therapy

    NARCIS (Netherlands)

    O.I.I. Soliman (Osama Ibrahim Ibrahim); D.A.M.J. Theuns (Dominic); M.L. Geleijnse (Marcel); A. Nemes (Attila); K. Caliskan (Kadir); W.B. Vletter (Wim); L.J.L.M. Jordaens (Luc); F.J. ten Cate (Folkert)

    2007-01-01

    textabstractAims: The current study sought to assess if pre-implantation lateral-to-septal delay (LSD) ≥60 ms assessed by spectral pulsed-wave myocardial tissue Doppler imaging (PW-TDI) could predict successful long-term outcome after cardiac resynchronization therapy (CRT). Methods and results Sixt

  2. Spectral pulsed-wave tissue Doppler imaging lateral-to-septal delay fails to predict clinical or echocardiographic outcome after cardiac resynchronization therapy

    NARCIS (Netherlands)

    O.I.I. Soliman (Osama Ibrahim Ibrahim); D.A.M.J. Theuns (Dominic); M.L. Geleijnse (Marcel); A. Nemes (Attila); K. Caliskan (Kadir); W.B. Vletter (Wim); L.J.L.M. Jordaens (Luc); F.J. ten Cate (Folkert)

    2007-01-01

    textabstractAims: The current study sought to assess if pre-implantation lateral-to-septal delay (LSD) ≥60 ms assessed by spectral pulsed-wave myocardial tissue Doppler imaging (PW-TDI) could predict successful long-term outcome after cardiac resynchronization therapy (CRT). Methods and results

  3. Spectral pulsed-wave tissue Doppler imaging lateral-to-septal delay fails to predict clinical or echocardiographic outcome after cardiac resynchronization therapy

    NARCIS (Netherlands)

    O.I.I. Soliman (Osama Ibrahim Ibrahim); D.A.M.J. Theuns (Dominic); M.L. Geleijnse (Marcel); A. Nemes (Attila); K. Caliskan (Kadir); W.B. Vletter (Wim); L.J.L.M. Jordaens (Luc); F.J. ten Cate (Folkert)

    2007-01-01

    textabstractAims: The current study sought to assess if pre-implantation lateral-to-septal delay (LSD) ≥60 ms assessed by spectral pulsed-wave myocardial tissue Doppler imaging (PW-TDI) could predict successful long-term outcome after cardiac resynchronization therapy (CRT). Methods and results Sixt

  4. Wind gust measurements using pulsed Doppler wind-lidar: comparison of direct and indirect techniques

    DEFF Research Database (Denmark)

    model, driven by the Doppler lidar measurements, which uses a non-linear particle filter to estimate the small-scale turbulent fluctuations. The first results show that the reconstruction method can reproduce the wind speed maxima measured by the sonic anemometer if a low-pass filter with a cut......-off frequency similar to the lidar measurement frequency is applied to the sonic data. These results from the reconstructed wind are better than the maxima derived directly from the wind lidar measurements. However, the maxima of the raw sonic anemometer signal are still higher than the maxima...

  5. Why Current Doppler Ultrasound Methodology Is Inaccurate in Assessing Cerebral Venous Return: The Alternative of the Ultrasonic Jugular Venous Pulse

    Directory of Open Access Journals (Sweden)

    Paolo Zamboni

    2016-01-01

    Full Text Available Assessment of cerebral venous return is growing interest for potential application in clinical practice. Doppler ultrasound (DUS was used as a screening tool. However, three meta-analyses of qualitative DUS protocol demonstrate a big heterogeneity among studies. In an attempt to improve accuracy, several authors alternatively measured the flow rate, based on the product of the time average velocity with the cross-sectional area (CSA. However, also the quantification protocols lacked of the necessary accuracy. The reasons are as follows: (a automatic measurement of the CSA assimilates the jugular to a circle, while it is elliptical; (b the use of just a single CSA value in a pulsatile vessel is inaccurate; (c time average velocity assessment can be applied only in laminar flow. Finally, the tutorial describes alternative ultrasound calculation of flow based on the Womersley method, which takes into account the variation of the jugular CSA overtime. In the near future, it will be possible to synchronize the electrocardiogram with the brain inflow (carotid distension wave and with the outflow (jugular venous pulse in order to nicely have a noninvasive ultrasound picture of the brain-heart axis. US jugular venous pulse may have potential use in neurovascular, neurocognitive, neurosensorial, and neurodegenerative disorders.

  6. Why Current Doppler Ultrasound Methodology Is Inaccurate in Assessing Cerebral Venous Return: The Alternative of the Ultrasonic Jugular Venous Pulse.

    Science.gov (United States)

    Zamboni, Paolo

    2016-01-01

    Assessment of cerebral venous return is growing interest for potential application in clinical practice. Doppler ultrasound (DUS) was used as a screening tool. However, three meta-analyses of qualitative DUS protocol demonstrate a big heterogeneity among studies. In an attempt to improve accuracy, several authors alternatively measured the flow rate, based on the product of the time average velocity with the cross-sectional area (CSA). However, also the quantification protocols lacked of the necessary accuracy. The reasons are as follows: (a) automatic measurement of the CSA assimilates the jugular to a circle, while it is elliptical; (b) the use of just a single CSA value in a pulsatile vessel is inaccurate; (c) time average velocity assessment can be applied only in laminar flow. Finally, the tutorial describes alternative ultrasound calculation of flow based on the Womersley method, which takes into account the variation of the jugular CSA overtime. In the near future, it will be possible to synchronize the electrocardiogram with the brain inflow (carotid distension wave) and with the outflow (jugular venous pulse) in order to nicely have a noninvasive ultrasound picture of the brain-heart axis. US jugular venous pulse may have potential use in neurovascular, neurocognitive, neurosensorial, and neurodegenerative disorders.

  7. B-Mode and pulsed Doppler sonography of kidney in healthy sheep according to age

    Directory of Open Access Journals (Sweden)

    Bianca P. Santarosa

    2016-06-01

    Full Text Available Abstract: There is no standardization in the literature of kidney length in sheep at different ages, as there are few studies about the access with the Doppler triplex ultrasound for the renal vascularization in this species. Eighty healthy sheep of three age groups of Ile de France and White Dorper breed were used: 20 lambs, 30 yearlings and 30 adults (8 rams and 22 ewes. Renal healthiness of the animals was confirmed by serum biochemical tests of urea and creatinine, and by observation of renal architecture with conventional ultrasound, besides measurement of vital parameters. A portable ultrasound (My LabTM30 Vet Gold Esaote®, Esaote Healthcare device was used, with a convex transducer with 3.5MHz frequency. After identification of the kidneys in two-dimensional mode, the measurement of length in the sagittal section was performed in all sheep (n=80. Then color Doppler was activated for visualization of renal and interlobar arteries of the right kidney, and the resistivity index (RI of the yearlings (n=30 and ewes (n=22 was measured. Biochemical tests remained within normal limits and renal architecture was preserved. The values of the right and left renal length were different between the groups, increasing with age (4.34cm and 4.31cm in lambs; 6.08cm and 6.23cm in yearlings; 7.57cm and 7.37cm in adults, respectively. Median values of RI of the renal artery were statistically different (p<0.05 between the groups of yearlings (0.57 and ewes (0.52. The median RI of the interlobar artery was similar in yearlings (0.58 and ewes (0.54.

  8. CDE估测阻塞性睡眠呼吸暂停对左心室整体功能的影响%Influence of Obstructive Sleep Apnea Syndrome on Left Ventricular Global Function by Color Doppler Echocardiography

    Institute of Scientific and Technical Information of China (English)

    王超; 张芬; 王雷; 宫坤; 郭艳杰

    2015-01-01

    Objective:Obstructive sleep apnea (OSA) may predispose patients to and heart failure.The aim of this study was to determine the index of myocardial performance ( IMP) reflecting left ventricular global function in uncomplicated OSA pa-tients.Methods:Fifty-eight subjects without hypertension,diabetes mellitus, and any cardiac or pulmonary disease referred for evaluation of OSA underwent overnight polysomnography and complete echocardiographic assessment.According to the apnea hy-popnea index ( AHI) , subjects were divided into three groups: group 1, control subjects with nonapneic snorers ( AHI30, n=19) . Basic echocardiographic measurements LVM index were measured. Left ventricular IMP was calculated as ( isovolumic contraction time+isovolumic relaxation time) /aortic ejection time by Doppler echocardiography. Results:There were no significant differ-ences in age, sex, body mass index, heart rate, and systolic and diastolic blood pressure among the three groups. Left ventricular IMP was significantly higher in severe OSA patients than in controls ( P30,N=19)。应用超声心动图测量基本数据,计算IMP指标。左室IMP=(等容收缩时间+等容舒张时间)/主动脉射血时间。结果:三组受试者在年龄、性别、身体质量指数,心率,收缩压和舒张压无显著差异。左室IMP在重度OSA患者比对照组(P<0.01)显著增高。对照组和轻中度OSA、轻中度OSA和重度OSA受试者之间无显著差异。结论:本研究表明,重度OSA可导致左心室整体功能不全。

  9. Micro-pulse upconversion Doppler lidar for wind and visibility detection in the atmospheric boundary layer

    CERN Document Server

    Xia, Haiyun; Wang, Chong; Shentu, Guoliang; Qiu, Jiawei; Zhang, Qiang; Dou, Xiankang; Pan, Jianwei

    2016-01-01

    For the first time, a versatile, eyesafe, compact and direct detection Doppler lidar is developed using upconversion single-photon detection method. An all-fiber and polarization maintaining architecture is realized to guarantee the high optical coupling efficiency and the system stability. Using integrated-optic components, the conservation of etendue of the optical receiver is achieved by manufacturing a fiber-coupled periodically poled Lithium niobate waveguide and an all-fiber Fabry-Perot interferometer (FPI). The so-called double-edge direct detection is implemented using a single-channel FPI and a single upconversion detector, incorporating time-division multiplexing method. The relative error of the system is lower than 0.1% over 9 weeks. To show the robust of the system, atmospheric wind and visibility over 48 hours are detected in the boundary layer. In the intercomparison experiments, lidar shows good agreement with the ultrasonic wind sensor (Vaisala windcap WMT52), with standard deviation of 1.04 ...

  10. Micro-pulse upconversion Doppler lidar for wind and visibility detection in the atmospheric boundary layer.

    Science.gov (United States)

    Xia, Haiyun; Shangguan, Mingjia; Wang, Chong; Shentu, Guoliang; Qiu, Jiawei; Zhang, Qiang; Dou, Xiankang; Pan, Jianwei

    2016-11-15

    For the first time, to the best of our knowledge, a compact, eye-safe, and versatile direct detection Doppler lidar is developed using an upconversion single-photon detection method at 1.5 μm. An all-fiber and polarization maintaining architecture is realized to guarantee the high optical coupling efficiency and the robust stability. Using integrated-optic components, the conservation of etendue of the optical receiver is achieved by manufacturing a fiber-coupled periodically poled lithium niobate waveguide and an all-fiber Fabry-Perot interferometer (FPI). The double-edge technique is implemented by using a convert single-channel FPI and a single upconversion detector, incorporating a time-division multiplexing method. The backscatter photons at 1548.1 nm are converted into 863 nm via mixing with a pump laser at 1950 nm. The relative error of the system is less than 0.1% over nine weeks. In experiments, atmospheric wind and visibility over 48 h are detected in the boundary layer. The lidar shows good agreement with the ultrasonic wind sensor, with a standard deviation of 1.04 m/s in speed and 12.3° in direction.

  11. Time dependent Doppler shifts in high-order harmonic generation in intense laser interactions with solid density plasma and frequency chirped pulses

    Energy Technology Data Exchange (ETDEWEB)

    Welch, E. C.; Zhang, P.; He, Z.-H. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109-2104 (United States); Dollar, F. [JILA, University of Colorado, Boulder, Colorado 80309 (United States); Krushelnick, K.; Thomas, A. G. R., E-mail: agrt@umich.edu [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109-2104 (United States); Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109-2104 (United States)

    2015-05-15

    High order harmonic generation from solid targets is a compelling route to generating intense attosecond or even zeptosecond pulses. However, the effects of ion motion on the generation of harmonics have only recently started to be considered. Here, we study the effects of ion motion in harmonics production at ultrahigh laser intensities interacting with solid density plasma. Using particle-in-cell simulations, we find that there is an optimum density for harmonic production that depends on laser intensity, which scales linearly with a{sub 0} with no ion motion but with a reduced scaling if ion motion is included. We derive a scaling for this optimum density with ion motion and also find that the background ion motion induces Doppler red-shifts in the harmonic structures of the reflected pulse. The temporal structure of the Doppler shifts is correlated to the envelope of the incident laser pulse. We demonstrate that by introducing a frequency chirp in the incident pulse we are able to eliminate these Doppler shifts almost completely.

  12. 成人心室双人口彩色多普勒超声心动图特征研究%Image characteristics of color Doppler echocardiography in adults with double-inlet ventricle

    Institute of Scientific and Technical Information of China (English)

    侯传举; 邹苏娅; 邓东安; 朱鲜阳; 韩秀敏; 刘剑立; 胡斌; 王巧玲

    2011-01-01

    Objectives To explore the image characteristics of color Doppler echocardiography (CDE) in adults with double-inlet ventricle (DIV). Methods Thirty-two adult patients with DIV were examined by CDE, and angiocardiography results were taken for contrast. Among them, 25 cases were confirmed by operation. Results Thirty adult cases were accurately diagnosed as DIV by CDE, and the accuracy rate reached 93.8% (30/32). Two cases were misdiagnosed as double-outlet right ventricle. The CDE characteristics in adults with DIV were as below; (1)Apical fourchamber views of two-dimensional echocardiography (2DE) showed intact atrial septum and total echo loss of ventricular septum. During systole, two atrioventricular valves closed, the"+"sign was replaced by"T" sign of 2DE; and during diastole, two atrioventricular valves opened to the one common ventricle. Color Doppler flow imaging (CDFI) showed that flow signals from the two atrium entered one common ventricle through two atrioventricular valves.(2)According to the features of the common ventricle on apical four-chamber view of 2DE, the ventricle of DIV could be devided into 3 types, as type A(65.6%, 21/32) with delicate echo in endocardium and trabecular muscles, type B(6.3%,2/32) with coarse echo, and type C (28.1%, 9/32), bulboventricular ridge could be seen in the apex of the common ventricle. (3)Type of the great arteries could be judged by view of parastemal short axis. Type I showed normal relationship of the two great arteries (15.6%, 5/32). Type Ⅱ and Ⅲ showed the same two circular echo signals of the two great arteries, but with different spatial relationships of the two circles, type Ⅱ (21.9%, 7/32) showed the two circles located in anterior right-posterior left direction and type Ⅲ (62.5%, 20/32) showed the two circles in anterior left-posterior right direction. The size of the two circles could be used to distinguish between pulmonary stenosis and pulmonary hypertension. Pulmonary stenosis(96.9%, 31

  13. Haemodynamic Optimization by Oesophageal Doppler and Pulse Power Wave Analysis in Liver Surgery: A Randomised Controlled Trial.

    Directory of Open Access Journals (Sweden)

    Aarne Feldheiser

    Full Text Available Liver surgery is still associated with a high rate of morbidity and mortality. We aimed to compare different haemodynamic treatments in liver surgery. In a prospective, blinded, randomised, controlled pilot trial patients undergoing liver resection were randomised to receive haemodynamic management guided by conventional haemodynamic parameters or by oesophageal Doppler monitor (ODM, CardioQ-ODM or by pulse power wave analysis (PPA, LiDCOrapid within a goal-directed algorithm adapted for liver surgery. The primary endpoint was stroke volume index before intra-operative start of liver resection. Secondary endpoints were the haemodynamic course during surgery and postoperative pain levels. Due to an unbalance in the extension of the surgical procedures with a high rate of only minor procedures the conventional group was dropped from the analysis. Eleven patients in the ODM group and 10 patients in the PPA group were eligible for statistical analysis. Stroke volume index before start of liver resection was 49 (37; 53 ml/m2 and 48 (41; 56 ml/m2 in the ODM and PPA group, respectively (p=0.397. The ODM guided group was haemodynamically stable as shown by ODM and PPA measurements. However, the PPA guided group showed a significant increase of pulse-pressure-variability (p=0.002 that was not accompanied by a decline of stroke volume index displayed by the PPA (p=0.556 but indicated by a decline of stroke volume index by the ODM (p<0.001. The PPA group had significantly higher postoperative pain levels than the ODM group (p=0.036. In conclusion, goal-directed optimization by ODM and PPA showed differences in intraoperative cardiovascular parameters indicating that haemodynamic optimization is not consistent between the two monitors.ISRCTN.com ISRCTN64578872.

  14. Analysis of Doppler Effect on the Pulse Compression of Different Codes Emitted by an Ultrasonic LPS

    Directory of Open Access Journals (Sweden)

    Jorge Morera

    2011-11-01

    Full Text Available This work analyses the effect of the receiver movement on the detection by pulse compression of different families of codes characterizing the emissions of an Ultrasonic Local Positioning System. Three families of codes have been compared: Kasami, Complementary Sets of Sequences and Loosely Synchronous, considering in all cases three different lengths close to 64, 256 and 1,024 bits. This comparison is first carried out by using a system model in order to obtain a set of results that are then experimentally validated with the help of an electric slider that provides radial speeds up to 2 m/s. The performance of the codes under analysis has been characterized by means of the auto-correlation and cross-correlation bounds. The results derived from this study should be of interest to anyone performing matched filtering of ultrasonic signals with a moving emitter/receiver.

  15. Analysis of Doppler effect on the pulse compression of different codes emitted by an ultrasonic LPS.

    Science.gov (United States)

    Paredes, José A; Aguilera, Teodoro; Alvarez, Fernando J; Lozano, Jesús; Morera, Jorge

    2011-01-01

    This work analyses the effect of the receiver movement on the detection by pulse compression of different families of codes characterizing the emissions of an ultrasonic local positioning system. Three families of codes have been compared: Kasami, Complementary Sets of Sequences and Loosely Synchronous, considering in all cases three different lengths close to 64, 256 and 1,024 bits. This comparison is first carried out by using a system model in order to obtain a set of results that are then experimentally validated with the help of an electric slider that provides radial speeds up to 2 m/s. The performance of the codes under analysis has been characterized by means of the auto-correlation and cross-correlation bounds. The results derived from this study should be of interest to anyone performing matched filtering of ultrasonic signals with a moving emitter/receiver.

  16. Wind turbines and bat mortality: Doppler shift profiles and ultrasonic bat-like pulse reflection from moving turbine blades.

    Science.gov (United States)

    Long, Chloe V; Flint, James A; Lepper, Paul A

    2010-10-01

    Bat mortality resulting from actual or near-collision with operational wind turbine rotors is a phenomenon that is widespread but not well understood. Because bats rely on information contained in high-frequency echoes to determine the nature and movement of a target, it is important to consider how ultrasonic pulses similar to those used by bats for echolocation may be interacting with operational turbine rotor blades. By assessing the characteristics of reflected ultrasonic echoes, moving turbine blades operating under low wind speed conditions (<6 m s(-1)) were found to produce distinct Doppler shift profiles at different angles to the rotor. Frequency shifts of up to ±700-800 Hz were produced, which may not be perceptible by some bat species. Monte Carlo simulation of bat-like sampling by echolocation revealed that over 50 rotor echoes could be required by species such as Pipistrellus pipistrellus for accurate interpretation of blade movement, which may not be achieved in the bat's approach time-window. In summary, it was found that echoes returned from moving blades had features which could render them attractive to bats or which might make it difficult for the bat to accurately detect and locate blades in sufficient time to avoid a collision.

  17. PMN-PT single crystal, high-frequency ultrasonic needle transducers for pulsed-wave Doppler application.

    Science.gov (United States)

    Zhou, Qifa; Xu, Xiaochen; Gottlieb, Emanuel J; Sun, Lei; Cannata, Jonathan M; Ameri, Hossein; Humayun, Mark S; Han, Pengdi; Shung, K Kirk

    2007-03-01

    High-frequency needle ultrasound transducers with an aperture size of 0.4 mm were fabricated using lead magnesium niobate-lead titanate (PMN-33% PT) as the active piezoelectric material. The active element was bonded to a conductive silver particle matching layer and a conductive epoxy backing through direct contact curing. An outer matching layer of parylene was formed by vapor deposition. The active element was housed within a polyimide tube and a 20-gauge needle housing. The magnitude and phase of the electrical impedance of the transducer were 47 omega and -38 degrees, respectively. The measured center frequency and -6 dB fractional bandwidth of the PMN-PT needle transducer were 44 MHz and 45%, respectively. The two-way insertion loss was approximately 15 dB. In vivo high-frequency, pulsed-wave Doppler patterns of blood flow in the posterior portion and in vitro ultrasonic backscatter microscope (UBM) images of the rabbit eye were obtained with the 44-MHz needle transducer.

  18. Pacemaker optimization guided by echocardiography in cardiac resynchronization therapy

    Directory of Open Access Journals (Sweden)

    Trifunović Danijela

    2009-01-01

    Full Text Available Introduction. Cardiac resynchronization therapy (CRT or biventricular pacing is a contemporary treatment in the management of advanced heart failure. Echocardiography plays an evolving and important role in patient selection for CRT, follow-up of acute and chronic CRT effects and optimization of device settings after biventricular pacemaker implantation. In this paper we illustrate usefulness of echocardiography for successful AV and VV timing optimization in patients with CRT. A review of up-to-date literature concerning rationale for AV and VV delay optimization, echocardiographic protocols and current recommendations for AV and VV optimization after CRT are also presented. Outline of Cases. The first case is of successful AV delay optimization guided by echocardiography in a patient with dilated cardiomyopathy treated with CRT is presented. Pulsed blood flow Doppler was used to detect mitral inflow while programming different duration of AV delay. The AV delay with optimal transmittal flow was established. The optimal mitral flow was the one with clearly defined E and A waves and maximal velocity time integral (VTI of the mitral flow. Improvement in clinical status and reverse left ventricle remodelling with improvement of ejection fraction was registered in our patient after a month. The second case presents a patient with heart failure caused by dilated cardiomyopathy; six months after CRT implantation the patient was still NYHA class III and with a significantly depressed left ventricular ejection fraction. Optimization of VV interval guided by echocardiography was undertaken measuring VTI of the left ventricular outflow tract (LVOT during programming of different VV intervals. The optimal VV interval was determined using a maximal LVOT VTI. A month after VV optimization our patient showed improvement in LV ejection fraction. Conclusion. Optimal management of patients treated with CRT integrate both clinical and echocardiographic follow

  19. Effect of Coronary Slow Flow on the Longitudinal Left Ventricular Function Assessed by 2-Dimensional Speckle-Tracking Echocardiography.

    Science.gov (United States)

    Narimani, Sima; Hosseinsabet, Ali; Pourhosseini, Hamidreza

    2016-04-01

    The coronary slow flow phenomenon is defined as the slow progression of an angiographic contrast agent to the distal part of the coronary arteries on selective coronary angiography in the absence of stenosis. There are some studies with different results about the effect of this phenomenon on left ventricular (LV) function. The aim of our study was to evaluate the longitudinal LV function in the coronary slow flow phenomenon using 2-dimensional (2D) speckle-tracking echocardiography. In a study with a patient-to-patient matched design, 36 patients with the coronary slow flow phenomenon and 36 individuals with normal coronary flow matched for age (±5 years), sex, hypertension, and diabetes mellitus were compared in terms of the longitudinal LV systolic and diastolic functions by pulsed wave tissue Doppler echocardiography and 2D speckle-tracking echocardiography-derived indices. Lateral s' and e' waves were lower in the patients with the coronary slow flow phenomenon, but there were no statistically significant differences between the groups regarding the other tissue Doppler echocardiographic indices and longitudinal systolic strain and systolic and diastolic strain rates derived by 2D speckle-tracking echocardiography. Our results showed that the coronary slow flow phenomenon could not impair the longitudinal LV systolic and diastolic functions. © 2016 by the American Institute of Ultrasound in Medicine.

  20. Invasive and noninvasive assessment of pulmonic regurgitation: clinical, angiographic, phonocardiographic, echocardiographic, and Doppler ultrasound correlations.

    Science.gov (United States)

    Chandraratna, P A; Wilson, D; Imaizumi, T; Ritter, W S; Aronow, W S

    1982-06-01

    Three patients with pulmonic regurgitation and no evidence of pulmonary hypertension were investigated. These patients had low pitched diastolic murmurs which increased on inspiration, evidence of connective tissue disease as manifested by lax joints and hyperextensible skin, and marked hilar dance which extended up to the peripheral vessels. Suprasternal echocardiography revealed dilatation and increased systolic expansion of the right pulmonary artery (RPA) (25% and 28%, respectively) in two patients; the third patient had a normal RPA dimension in diastole and a marked increase in diameter (88%) in systole. Thus, these three patients demonstrated hyperdistensibility of the RPA. The spectral signal from the pulsed doppler echocardiograph showed evidence of turbulent blood flow in diastole (wide dispersion of the dots) in the right ventricular outflow tract in all three patients. This pattern was indicative of pulmonic regurgitation. In summary, the combined use of echocardiography and Doppler ultrasound is useful in the evaluation of patients with pulmonic regurgitation.

  1. A feasible method for non-invasive measurement of pulmonary vascular resistance in pulmonary arterial hypertension: Combined use of transthoracic Doppler-echocardiography and cardiac magnetic resonance. Non-invasive estimation of pulmonary vascular resistance.

    Science.gov (United States)

    Yan, Chaowu; Xu, Zhongying; Jin, Jinglin; Lv, Jianhua; Liu, Qiong; Zhu, Zhenhui; Pang, Kunjing; Shi, Yisheng; Fang, Wei; Wang, Yang

    2015-12-07

    Transthoracic Doppler-echocardiography (TTE) can estimate mean pulmonary arterial pressure (MPAP) and pulmonary capillary wedge pressure (PCWP) reliably, and cardiac magnetic resonance (CMR) is the best modality for non-invasive measurement of cardiac output (CO). We speculated that the combined use of TTE and CMR could provide a feasible method for non-invasive measurement of pulmonary vascular resistance (PVR) in pulmonary arterial hypertension (PAH). Right heart catheterization (RHC) was undertaken in 77 patients (17M/60F) with PAH, and simultaneous TTE was carried out to evaluate MPAP, PCWP and CO. Within 2 days, CO was measured again with CMR in similar physiological status. Then, PVR was calculated with the integrated non-invasive method: TTE-derived (MPAP-PCWP)/CMR-derived CO and the isolated TTE method: TTE-derived (MPAP-PCWP)/TTE-derived CO, respectively. The PVR calculated with integrated non-invasive method correlated well with RHC-calculated PVR (r = 0.931, 95% confidence interval 0.893 to 0.956). Between the integrated non-invasive PVR and RHC-calculated PVR, the Bland-Altman analysis showed the satisfactory limits of agreement (mean value: - 0.89 ± 2.59). In comparison, the limits of agreement were less satisfactory between TTE-calculated PVR and RHC-calculated PVR (mean value: - 1.80 ± 3.33). Furthermore, there were excellent intra- and inter-observer correlations for the measurements of TTE and CMR (P measurement of PVR is very important in clinical practice. Up to now, however, the widely accepted non-invasive method is still unavailable. Since TTE can estimate (MPAP-PCWP) reliably and CMR is the best image modality for the measurement of CO, the combined use of two modalities has the potential to determine PVR non-invasively. In this research, the integrated non-invasive method showed good diagnostic accuracy and repeatability compared with RHC. Therefore, it might be a feasible method for non-invasive measurement of PVR in patients

  2. Transcranial measurement of blood velocities in the basal cerebral arteries using pulsed Doppler ultrasound: a method of assessing the Circle of Willis.

    Science.gov (United States)

    Padayachee, T S; Kirkham, F J; Lewis, R R; Gillard, J; Hutchinson, M C; Gosling, R G

    1986-01-01

    Transcranial pulsed Doppler ultrasound and spectral analysis were used for detection of blood velocities in the basal cerebral arteries. The Doppler transducer was placed superior to the zygomatic arch and during insonation of the middle cerebral artery care was taken to obtain maximum Doppler-shift frequency signals since this allowed a small angle between the ultrasound beam and this artery. Doppler signals were obtained from the middle, anterior, and posterior cerebral arteries in 20 volunteers with the average depth of the Doppler gate at 4.9 (4.6-5.2 cm), 5.2 (4.9-5.4 cm), and 6.3 cm (6.0-6.9 cm), respectively. These measurements were in agreement with those obtained for 15 cadaver studies, in whom the distance from the proposed site of the Doppler transducer to each basal cerebral artery was measured as 4.7 +/- 0.6, 5.3 +/- 0.5, and 5.9 +/- 0.9 cm, respectively. The reproducibility of middle cerebral artery blood velocity values was tested in seven subjects and showed a variation of not more than 8% in any individual. The method was used in combination with common carotid compression to assess four patients who had occlusive extracranial carotid disease; in three the disease was more severe on one side and reversal of blood flow in the proximal ipsilateral anterior cerebral artery was demonstrated, consistent with cross flow from the contralateral side via the anterior communicating artery of the Circle of Willis. In the fourth patient augmentation of posterior cerebral artery blood velocities during common carotid compression indicated the major collateral source was from the vertebrobasilar system.

  3. Recent advances in echocardiography for nuclear medicine physician

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Geu Ru; Shin, Dong Gu [Yeungnam University College of Medicine, Daegu (Korea, Republic of)

    2005-10-15

    Echocardiography is one of the most frequently used techniques for diagnosing cardiovascular diseases. Over the last twenty years, technological advances have enabled the application of high-quality imaging. Important recent developments have occurred in echocardiography that are already being used clinically. Equipment and hardware is now available to produce real time three-dimensional and contrast enhanced imaging. Tissue Doppler and stress echocardiography have provided potential benefit to analyze hemodynamic information of heart. This review discusses each of these new developments and their potential impact on the practice of echocardiography and cardiology in general.

  4. Influence of arterial compliance on presence and extent of ischaemia during stress echocardiography

    Science.gov (United States)

    Haluska, B A; Matthys, K; Fathi, R; Rozis, E; Carlier, S G; Marwick, T H

    2006-01-01

    Objective To seek an association between total arterial compliance (TAC) and the extent of ischaemia at stress echocardiography. Design Cohort study. Setting Regional cardiac centre. Methods 255 consecutive patients (147 men; mean (SD) age 58 (8)) presenting for stress echocardiography for clinical indications were studied. Wall motion score index (WMSI) was calculated and ischaemia was defined by an inducible or worsening wall motion abnormality. Peak WMSI was used to reflect the extent of dysfunction (ischaemia or scar), and ΔWMSI was indicative of extent of ischaemia. TAC was assessed at rest by simultaneous radial applanation tonometry and pulsed wave Doppler in all patients. Results Ischaemia was identified by stress echocardiography in 65 patients (25%). TAC was similar in the groups with negative and positive echocardiograms (1.08 (0.41) v 1.17 (0.51) ml/mm Hg, not significant). However, the extent of dysfunction was associated with TAC independently of age, blood pressure, risk factors, and use of a β blocker. Moreover, the extent of ischaemia was determined by TAC, risk factors, and use of a β blocker. Conclusion While traditional cardiovascular risk factors are strong predictors of ischaemia on stress echocardiography, TAC is an independent predictor of the extent of ischaemia. PMID:16365349

  5. Measurements of ion temperature and flow of pulsed plasmas produced by a magnetized coaxial plasma gun device using an ion Doppler spectrometer

    Science.gov (United States)

    Kitagawa, Y.; Sakuma, I.; Iwamoto, D.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.

    2012-10-01

    It is important to know surface damage characteristics of plasma-facing component materials during transient heat and particle loads such as type I ELMs. A magnetized coaxial plasma gun (MCPG) device has been used as transient heat and particle source in ELM simulation experiments. Characteristics of pulsed plasmas produced by the MCPG device play an important role for the plasma material interaction. In this study, ion temperature and flow velocity of pulsed He plasmas were measured by an ion Doppler spectrometer (IDS). The IDS system consists of a light collection system including optical fibers, 1m-spectrometer and a 16 channel photomultiplier tube (PMT) detector. The IDS system measures the width and Doppler shift of HeII (468.58 nm) emission line with the time resolution of 1 μs. The Doppler broadened and shifted spectra were measured with 45 and 135 degree angles with respect to the plasmoid traveling direction. The observed emission line profile was represented by sum of two Gaussian components to determine the temperature and flow velocity. The minor component at around the wavelength of zero-velocity was produced by the stationary plasma. As the results, the ion velocity and temperature were 68 km/s and 19 eV, respectively. Thus, the He ion flow energy is 97 eV. The observed flow velocity agrees with that measured by a time of flight technique.

  6. Ultrasonic colour Doppler imaging

    DEFF Research Database (Denmark)

    Evans, David H.; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue ...

  7. A Study on Imaging Characteristics of Color Doppler Echocardiography on Adult Dextrocardia with Cardiovascular Malformations%成人右旋心及合并畸形彩色多普勒超声心动图特征

    Institute of Scientific and Technical Information of China (English)

    侯传举; 李燕萍; 邓东安; 朱鲜阳; 韩秀敏; 刘剑立; 胡斌; 王巧玲

    2011-01-01

    Purpose To explore the imaging characteristics of color Doppler echocardiography(CDE) on adult dextrocardia with cardiovascular malformations.Materials and Methods Thirty patients with dextrocardia with cardiovascular malformations were detected by CDE and the imaging characteristics of CDE were investigated.All cases underwent angiocardiography examination as control.26 cases were proved by surgery.Results All cases were diagnosed correctly, according to CDE imaging features.The imaging features of CDE of adult dextrocardia with cardiovascular malformation are very obvious: ①Adult dextrocardia usually includes 4 kinds of congenital heart disease,among which type SLL corrective transposition of the great arteies are common (80%) ,type AⅢ double-inlet ventricle ( 10.0%) ,type SLL double outlet of right ventricle (6.7%) and isolated atrial septal defect (3.3%) is rare.②No matter which kind of congenital heart disease adult dextrocardia combined, CDE results all showed orthotopic heart.③Adult dextrocardia which combined corrective transposition of the great arteies,double-inlet ventricle and double outlet of right ventricle is left-transposition.④Among adult dextrocardia combined with complex congenital heart disease,many of them emerged pulmonary stenosis (93.3%) ,in which color Doppler flow imaging showed multicoloured enchase jet bouquet of blood flow signals through pulmonary artery.⑤In cases of atral septal defect and ventricular septal defect, color Doppler flow imaging showed left to right or bidirection multicoloured enchase shunt bouquet of blood flow signals across interatrial septum or interventricular septum.Conclusion The characteristics of CDE on adult dextrocardia and cardiovascular deformity are obvious.CDE can be used to diagnose this correctly, when the operators of CDE has an excellent demand of the anatomy of this disease.The exploration technique of the disease is obviously different from those of normal position heart

  8. Advanced techniques in echocardiography in small animals.

    Science.gov (United States)

    Chetboul, Valérie

    2010-07-01

    Transthoracic echocardiography has become a major imaging tool for the diagnosis and management of canine and feline cardiovascular diseases. During the last decade, more recent advances in ultrasound technology with the introduction of newer imaging modalities, such as tissue Doppler imaging, strain and strain rate imaging, and 2-dimensional speckle tracking echocardiography, have provided new parameters to assess myocardial performance, including regional myocardial velocities and deformation, ventricular twist, and mechanical synchrony. An outline of these 4 recent ultrasound techniques, their impact on the understanding of right and left ventricular function in small animals, and their application in research and clinical settings are given in this article.

  9. American Society of Echocardiography

    Science.gov (United States)

    American Society of Echocardiography Join Ase Member Portal Log In Membership Member Portal Log In Join ASE Renew Benefits Rates FASE – Fellow of the American Society of Echocardiography Member Referral Program FAQs Initiatives Advocacy ...

  10. Diagnostic value of Doppler echocardiography in patients undergoing mitral and aortic valve replacement%多普勒超声心动图对二尖瓣及主动脉瓣置换术的诊断价值

    Institute of Scientific and Technical Information of China (English)

    罗丽敏; 黄枢

    2016-01-01

    Objective To explore the clinical effect of Doppler echocardiography in the diagnosis of mitral replacement surger-y.Methods 186 patients who had received mitral and aortic valve, double valve replacement with mechanical prosthetic valve in our hospital between December 2010 and December 2015 were selected.The echocardiography results of the patients were ana-lyzed before and after surgery.Results After the surgery, the LA and LV of all the patients were significantly lower than before surgery, and RV, LVEF and LVFS were significantly higher than before, with statistically significant difference ( P <0.05).For patients with mitral stenosis, the LA, LAA, LV, LAV, MPGmv, VTImv and PHTmv after the surgery were all lower than before the surgery, and the differences were significant ( P <0.05) .Postoperative EOAmv and EOAImv were shown to be significantly higher than fore surgery, where the difference was significant ( P <0.05) .For patients with mitral regurgitation, the LA and LV after the surgery were both lower than before the surgery, and the difference was significant ( P <0.05).For patients with aortic valve stenosis, the LA, LAM, IVS Vav and MPGav after the surgery were all lower than before the surgery, and the differences were significant ( P <0.05);Postoperative EOAav and EOAIav were shown to be significantly higher than fore surgery, where the difference was significant ( P <0.05).For patients with aortic regurgitation, the LA, LAMI, EOAav and EOAIav after the surgery were all lower than before the surgery, and the differences were significant ( P <0.05); Postoperative Vav and PGav were shown to be significantly higher than fore surgery, where the difference was significant ( P <0.05).The proportion of mis-match between heart valve prosthesis and mitral valve was less than that between heart valve prosthesis and aortic valve, and the difference was significant ( P <0.05) .Conclusion For patients with valvular heart disease, double valve replacement can im

  11. Ecocardiografia por Doppler tecidual no diagnóstico de rejeição após transplante cardíaco Ecocardiografía con Doppler tisular en el diagnóstico de rechazo después de transplante cardíaco Tissue doppler echocardiography in the diagnosis of heart transplantation rejection

    Directory of Open Access Journals (Sweden)

    Marcos Valério Coimbra Resende

    2011-07-01

    Full Text Available FUNDAMENTO: A biópsia endomiocárdica (BEM é o método padrão-ouro para o diagnóstico de rejeição celular (RC após transplante cardíaco (TC. OBJETIVO: Testar a hipótese de que o exame de imagem por Doppler tecidual (IDT pode detectar RC > 3A e agregar informação diagnóstica, comparado ao Doppler convencional. MÉTODOS: Cinquenta e quatro pacientes com TC foram submetidos à BEM e estudo ecocardiográfico através de IDT em até 24 horas. Comparamos os pacientes com TC e RC > 3A com pacientes com TC e RC 3A em 39/129 (30,2% das BEM. O melhor preditor isolado para o diagnóstico de RC foi a a'LAT, com sensibilidade de 76,3%, especificidade de 73,8% (p = 0,001. Na análise multivariada, a a'LAT (p = 0,001, a'SEP (p = 0,002, relação e'/a' LAT (p = 0,006, relação e'Mitral/ e'LAT (p = 0,014, SINF (p = 0,009 foram preditores de RC > 3A. Obtivemos um escore com sensibilidade de 88,2%, acurácia de 79,6%, e valor preditivo negativo de 92,9% para diagnosticar RC > 3A. O Doppler convencional (fluxo mitral e pulmonar venoso não foi relevante para predizer a RC > 3A. CONCLUSÃO: O estudo de IDT agregou informação diagnóstica para predizer RC > 3A quando comparado ao Doppler convencional. O modelo baseado em IDT pode ser tornar um método em potencial para detectar RC > 3A após TC.FUNDAMENTO: La biopsia endomiocárdica (BEM es el método gold standard para el diagnóstico de rechazo celular (RC después de transplante cardíaco (TC. OBJETIVO: Testear la hipótesis de que el examen de imagen con Doppler tisular (IDT puede detectar RC > 3A y agregar información diagnóstica, comparado al Doppler convencional. MÉTODOS: Cincuenta y cuatro pacientes con TC fueron sometidos a BEM y estudio ecocardiográfico a través de IDT en hasta 24 horas. Comparamos los pacientes con TC y RC > 3A con pacientes con TC y RC 3A en 39/129 (30,2% de las BEM. El mejor predictor aislado para el diagnóstico de RC fue la a'LAT, con sensibilidad de 76

  12. Trans-esophageal echocardiography for tricuspid and pulmonary valves

    Directory of Open Access Journals (Sweden)

    Prabhu Mahesh

    2009-01-01

    Full Text Available Transesophageal echocardiography has been shown to provide unique information about cardiac anatomy, function, hemodynamics and blood flow and is relatively easy to perform with a low risk of complications. Echocardiographic evaluation of the tricuspid and pulmonary valves can be achieved with two-dimensional and Doppler imaging. Transesophageal echocardiography of these valves is more challenging because of their complex structure and their relative distance from the esophagus. Two-dimensional echocardiography allows an accurate visualization of the cardiac chambers and valves and their motion during the cardiac cycle. Doppler echocardiography is the most commonly used diagnostic technique for detecting and evaluating valvular regurgitation. The lack of good quality evidence makes it difficult to recommend a validated quantitative approach but expert consensus recommends a clinically useful qualitative approach. This review ennumerates probe placement, recommended cross-sectional views, flow patterns, quantitative equations including the clinical approach to the noninvasive quantification of both stenotic and regurgitant lesions.

  13. Hole-burning in an Autler-Townes doublet and in superluminal (subluminal) Electromagnetically induced transparency of a light pulse via a joint nonlinear coherent Kerr effect and Doppler broadening

    CERN Document Server

    Bacha, Bakhtt A; Ahmad, Iftikhar

    2013-01-01

    We investigate the behavior of light pulse propagation in a 4-level double Lambda atomic system under condition of electromagnetically induced transparency. The Fano type interference effect and spectral hole burning appears in the the dynamics of the absorption-dispersion spectra caused by the joint nonlinear coherence Kerr effect and Doppler broadening. The coherent Kerr effect exhibits an enhancement (reduction) in superluminal (subluminal) in negative (in positive) group index while the Doppler broadening generates multiple hole burning in the Autler-Townes like spectra of this system. The hole burning in addition with coherent Kerr effect on the spectral profile influences the dynamics of subluminal and superluminal of the probe pulse through the medium. The characteristics of superluminality and subluminality modified by considering cold-Kerr-free medium and hot-Kerr-dependent mediums. The light pulse delays and advances in different regions of dispersion medium with the Doppler broadening and coherent ...

  14. Prevalência de hipertensão pulmonar avaliada por ecocardiografia Doppler em uma população de pacientes adolescentes e adultos com fibrose cística Prevalence of pulmonary hypertension evaluated by Doppler echocardiography in a population of adolescent and adult patients with cystic fibrosis

    Directory of Open Access Journals (Sweden)

    Paula Maria Eidt Rovedder

    2008-02-01

    Full Text Available OBJETIVO: Determinar a prevalência de hipertensão pulmonar (HP em pacientes com fibrose cística (FC, comparar características clínicas, escore radiológico, função pulmonar e parâmetros ecocardiográficos nos grupos com e sem HP e correlacionar achados ecocardiográficos com características clínicas, escore radiológico e função pulmonar. MÉTODOS: Estudo transversal prospectivo em pacientes clinicamente estáveis (idade > 16 anos atendidos por um programa de adultos para FC. Os pacientes foram submetidos a avaliação clínica, ecocardiografia Doppler, testes de função pulmonar e exame radiológico do tórax. RESULTADOS: Obteve-se a velocidade de regurgitação tricúspide (VRT em 37 dos 40 pacientes estudados. A prevalência de HP foi de 49% com um ponte de corte da VRT de 2,5 m/s (18 pacientes e de 30% com um ponte de corte da VRT de 2,8 m/s (11 pacientes. Os valores de saturação periférica de oxigênio (SpO2 em repouso, escore clínico, volume expiratório forçado no primeiro segundo (VEF1 e capacidade vital forçada (CVF foram significativamente menores no grupo com HP. A VRT correlacionou-se significativamente com SpO2 em repouso (p OBJECTIVE: To determine the prevalence of pulmonary hypertension (PH in patients with cystic fibrosis (CF, to compare clinical characteristics, radiographic scores, pulmonary function, and echocardiographic parameters in patients with and without PH, and to correlate echocardiographic findings with clinical characteristics, radiographic scores, and pulmonary function. METHODS: This was a prospective, cross-sectional study involving clinically stable patients (aged 16 or older enrolled in an adult CF program. The patients were submitted to clinical evaluation, Doppler echocardiography, pulmonary function tests, and chest X-rays. RESULTS: Tricuspid regurgitant jet velocity (TRV was obtained in 37 of the 40 patients studied. The prevalence of PH was 49% with a TRV cut-off of 2.5 m/s (18 patients

  15. Pulsed Doppler Radar for Low Speed Target Detection%脉冲多普勒雷达低速目标检测技术

    Institute of Scientific and Technical Information of China (English)

    郭玲红; 李亚立

    2012-01-01

    The principles of pulsed doppler radar for target detection and the characteristics of low speed target detection are analysed. The leakages of emission signal, local oscillator signal, frequency multiply signal of synchronizing pulse and crystal oscillator output are the reasons that effecting of pulsed doppler radar on the low speed target detection. So isolation' s raising, wideband signal reception and emission signal frequency offset are the solution measures to realize low speed target detection effectively. Experimental study proved the validity of analysis and measures.%通过对脉冲多普勒雷达目标检测原理和低速目标检测特点的分析,确定了来自于雷达系统中的发射信号泄露、本振信号泄露、同步脉冲及DDS信号倍频分量泄露、晶振信号倍频分量泄露等是影响脉冲多普勒雷达对于低速目标检测的主要因素,依托现有硬件水平,通过提高系统的收发隔离度、采用宽带接收和发射频率预偏移等技术措施,保证泄漏信号远小于回波信号,从而有效地实现了对低速目标的检测,并通过实验验证了设计的正确性和措施的有效性。

  16. Ultrasonic colour Doppler imaging

    DEFF Research Database (Denmark)

    Evans, David H; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    anatomy. The most common use of the technique is to image the movement of blood through the heart, arteries and veins, but it may also be used to image the motion of solid tissues such as the heart walls. Colour Doppler imaging is now provided on almost all commercial ultrasound machines, and has been......Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue...... vectors. This review briefly introduces the principles behind colour Doppler imaging and describes some clinical applications. It then describes the basic components of conventional colour Doppler systems and the methods used to derive velocity information from the ultrasound signal. Next, a number of new...

  17. QUANTITATIVE ANALYSIS ON CHANGES OF HEPATIC HEMODYNAMICS AFTER TRANSCUTANEOUS ELECTRIC PULSE STIMULATION OF LOCAL POINTS BY USING COLOR DOPPLER ULTRASOUND DIAGNOSTIC APPARATUS

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jun-chang; WANG Ling; LI Hong; LI Jun; ZHANG Yun

    2006-01-01

    Objective: To evaluate the effect of transcutaneous electric pulse stimulation (TEPS) on hepatic blood flow and parenchymal microcirculation in patients with fatty liver. Methods: A total of 31 fatty liver volunteer patients were observed in this study. Changes of color Doppler energy (CDE) images before and after TEPS of local points nearby the liver were recorded by using color Doppler ultrasound diagnostic apparatus (ACUSON 128XP/10C). Sum of color pixel area (SCPA), average of color value (ACV) and SCPA×ACV (integral) of the hepatic flow images were analyzed by an image processing system, single blind method and paired t-test. Programmed TEPS (0.5- 150 Hz/2 000 Hz, 10-25 V) was applied to the right Qimen (期门LR 14)-Jingmen (京门GB 25), Fuai (腹哀 SP 16)-Ganshu (肝俞 BL 18) respectively for 15 min. Results:Compared with basic values of pretreatment, SCPA, ACV and SCPA×ACV increased significantly ( t = 2.71,P<0.02; t=3.42, P<0.01; and t=8.15, P<0.001 ) after TEPS, meaning improvement of hepatic blood flow supply. Conclusion: TEPS of acupoints near the liver can improve hepatic blood flow and hepatic parenchyrnal microcirculation in patients with fatty liver.

  18. Assessment of left ventricular function by tissue Doppler imaging in patients with ankylosing spondylitis

    Directory of Open Access Journals (Sweden)

    Osman Kuloglu

    2012-05-01

    Full Text Available Ankylosing spondylitis (ASpis a chronic, inflammatory and systemic disease affecting pericardium, myocardium and the conduction system of the heart. In this study, we aimed to analyse left ventricular systolic and diastolic functions using tissue Doppler imaging (TDI. 30 patients with ASp and 30 healthy volunteers having the similar demographic characteristics were included. Left ventricular systolic and diastolic functions were assessed by using two dimensional (2D echocardiography, M-mode, pulsed-wave (PW and tissue Doppler echocardiography. The peak systolic velocity (Sm, early diastolic myocardial peak velocity (m, late diastolic myocardial peak velocity (Am, isovolumic acceleration (IVA, myocardial precontraction time (PCTm, myocardial contraction time (CTm, myocardial relaxation time (RTm, and myocardial performance index (MPI were measured at septal and lateral mitral annulus. In conventional echocardiography, end-diastolic interventricular septum and posterior wall diameters were higher in patients with ASp than the control group. The ratio of E/A was significantly lower and deceleration time was significantly prolonged in patients with ASp, but mitral E and A velocities, isovolumic relaxation time and MPI were similar in patient and control group (P>0.05. Left ventricular lateral and septal wall tissue Doppler echocardiography showed that Em, Em/Am ratio and CTm were significantly lower, IVRTm was longer and MPI was higher in patients with ASp. No significant differences were detected between the groups for IVA, Sm, Am, PCTm, PCTm/CTm ratio (P>0.05. We have demonstrated that in patients with ASp, diastolic functions were impaired but systolic functions were preserved by using TDI.

  19. Real-time parallel implementation of Pulse-Doppler radar signal processing chain on a massively parallel machine based on multi-core DSP and Serial RapidIO interconnect

    Science.gov (United States)

    Klilou, Abdessamad; Belkouch, Said; Elleaume, Philippe; Le Gall, Philippe; Bourzeix, François; Hassani, Moha M'Rabet

    2014-12-01

    Pulse-Doppler radars require high-computing power. A massively parallel machine has been developed in this paper to implement a Pulse-Doppler radar signal processing chain in real-time fashion. The proposed machine consists of two C6678 digital signal processors (DSPs), each with eight DSP cores, interconnected with Serial RapidIO (SRIO) bus. In this study, each individual core is considered as the basic processing element; hence, the proposed parallel machine contains 16 processing elements. A straightforward model has been adopted to distribute the Pulse-Doppler radar signal processing chain. This model provides low latency, but communication inefficiency limits system performance. This paper proposes several optimizations that greatly reduce the inter-processor communication in a straightforward model and improves the parallel efficiency of the system. A use case of the Pulse-Doppler radar signal processing chain has been used to illustrate and validate the concept of the proposed mapping model. Experimental results show that the parallel efficiency of the proposed parallel machine is about 90%.

  20. Coronary flow velocity analysis during short term follow up after coronary reperfusion: use of transthoracic Doppler echocardiography to predict regional wall motion recovery in patients with acute myocardial infarction

    OpenAIRE

    Hozumi, T; Kanzaki, Y; Ueda, Y.; Yamamuro, A; Takagi, T; Akasaka, T; Homma, S; Yoshida, K.; Yoshikawa, J

    2003-01-01

    Background: A recent study using a Doppler guide wire showed that coronary flow velocity measurements immediately after coronary reperfusion were useful in predicting recovery of regional left ventricular function. The value of coronary flow velocity analyses during follow up after reperfusion has not been established in the clinical setting.

  1. Association of pulse pressure with left ventricular geometry and function in elderly nonhypertensive patients with diabetes: A 3D speckle tracking echocardiography study.

    Science.gov (United States)

    Wang, Qingqing; Tan, Kaibin; Xia, Hongmei; Gao, Yunhua

    2017-09-01

    The aims of this study were to investigate and compare the left ventricular (LV) geometry and function in elderly nonhypertensive type 2 diabetic patients with normal (NPP, geometry were found among the three groups (p = 0.015), and concentric geometry was most prevalent in the diabetic patients with HPP. The diabetic patients with NPP only showed significantly lower GLS than the controls (p < 0.05). However, the diabetic patients with HPP showed significantly lower LVEF and severely lower strain values in all directions than the controls and the diabetic patients with NPP (p < 0.01or p < 0.05 or p < 0.001). Fasting plasma glucose, HPP, and body mass index were independently associated with all strain parameters in diabetic patients. The combination of conventional echocardiography and 3DSTE could detect LV subclinical abnormalities in nonhypertensive type 2 diabetic patients with NPP and HPP. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:416-425, 2017. © 2017 Wiley Periodicals, Inc.

  2. Usefulness and limitations of transthoracic echocardiography in heart transplantation recipients

    Directory of Open Access Journals (Sweden)

    Galderisi Maurizio

    2008-01-01

    Full Text Available Abstract Transthoracic echocardiography is a primary non-invasive modality for investigation of heart transplant recipients. It is a versatile tool which provides comprehensive information about cardiac structure and function. Echocardiographic examinations can be easily performed at the bedside and serially repeated without any patient's discomfort. This review highlights the usefulness of Doppler echocardiography in the assessment of left ventricular and right ventricular systolic and diastolic function, of left ventricular mass, valvular heart disease, pulmonary arterial hypertension and pericardial effusion in heart transplant recipients. The main experiences performed by either standard Doppler echocardiography and new high-tech ultrasound technologies are summarised, pointing out advantages and limitations of the described techniques in diagnosing acute allograft rejection and cardiac graft vasculopathy. Despite the sustained efforts of echocardiographic technique in predicting the biopsy state, endocardial myocardial biopsies are still regarded as the gold standard for detection of acute allograft rejection. Conversely, stress echocardiography is able to identify accurately cardiac graft vasculopathy and has a recognised prognostic in this clinical setting. A normal stress-echo justifies postponement of invasive studies. Another use of transthoracic echocardiography is the monitorisation and the visualisation of the catheter during the performance of endomyocardial biopsy. Bedside stress echocardiography is even useful to select appropriately heart donors with brain death. The ultrasound monitoring is simple and effective for monitoring a safe performance of biopsy procedures.

  3. Doppler ultrasound in obstetrics and gynecology. 2. rev. and enl. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Maulik, D. [Winthrop Univ. Hospital, Mineola, NY (United States). Dept. of Obstetrics and Gynecology; Zalud, I. (eds.) [Kapiolani Medical Center for Women and Children, Honolulu, HI (United States)

    2005-07-01

    The second edition of Doppler Ultrasound in Obstetrics and Gynecology has been expanded and comprehensively updated to present the current standards of practice in Doppler ultrasound and the most recent developments in the technology. Doppler Ultrasound in Obstetrics and Gynecology encompasses the full spectrum of clinical applications of Doppler ultrasound for the practicing obstetrician-gynecologist, including the latest advances in 3D and color Doppler and the newest techniques in 4D fetal echocardiography. Written by preeminent experts in the field, the book covers the basic and physical principles of Doppler ultrasound; the use of Doppler for fetal examination, including fetal cerebral circulation; Doppler echocardiography of the fetal heart; and the use of Doppler for postdated pregnancy and in cases of multiple gestation. Chapters on the use of Doppler for gynecologic investigation include ultrasound in ectopic pregnancy, for infertility, for benign disorders and for gynecologic malignancies. (orig.)

  4. Clinical Stress Echocardiography

    NARCIS (Netherlands)

    S.E. Karagiannis

    2007-01-01

    textabstractTwo-dimensional echocardiography is a commonly used non-invasive method for the assessment of left ventricular function. It provides precise information on both global and segmental myocardial function by displaying endocardial motion and wall thickening. Dobutamine stress

  5. Pulse

    Science.gov (United States)

    ... resting for at least 10 minutes. Take the exercise heart rate while you are exercising. ... pulse rate can help determine if the person's heart is pumping. Pulse ... rate gives information about your fitness level and health.

  6. Three-dimensional echocardiography

    Energy Technology Data Exchange (ETDEWEB)

    Buck, Thomas [University Hospital Essen (Germany). West German Heart Center; Franke, Andreas [Klinikum Region Hannover - Klinikum Siloah, Hannover (Germany). Dept. of Cardiology, Angiology and Intensive Care Medicine; Monaghan, Mark J. (eds.) [King' s College Hospital, London (United Kingdom)

    2011-07-01

    Presents tips and tricks for beginners and experts Provides educational material for 3D training courses Features comprehensively illustrated cases Includes an accompanying DVD with video clips of all sample cases Three-dimensional echocardiography is the most recent fundamental advancement in echocardiography. Since real-time 3D echocardiography became commercially available in 2002, it has rapidly been accepted in echo labs worldwide. This book covers all clinically relevant aspects of this fascinating new technology, including a comprehensive explanation of its basic principles, practical aspects of clinical application, and detailed descriptions of specific uses in the broad spectrum of clinically important heart disease. The book was written by a group of well-recognized international experts in the field, who have not only been involved in the scientific and clinical evolution of 3D echocardiography since its inception but are also intensively involved in expert training courses. As a result, the clear focus of this book is on the practical application of 3D echocardiography in daily clinical routine with tips and tricks for both beginners and experts, accompanied by more than 150 case examples comprehensively illustrated in more than 800 images and more than 500 videos provided on a DVD. In addition to an in-depth review of the most recent literature on real-time 3D echocardiography, this book represents an invaluable reference work for beginners and expert users of 3D echocardiography. - Tips and tricks for beginners and experts - Educational material for 3D training courses - Comprehensively illustrated cases - DVD with video clips of all sample cases.

  7. General principles of carotid Doppler ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Whal [Dept. of Radiology, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2014-03-15

    Carotid Doppler ultrasonography is a popular tool for evaluating atherosclerosis of the carotid artery. Its two-dimensional gray scale can be used for measuring the intima-media thickness, which is very good biomarker for atherosclerosis and can aid in plaque characterization. The plaque morphology is related to the risk of stroke. The ulceration of plaque is also known as one of the strong predictors of future embolic event risk. Color Doppler ultrasonography and pulse Doppler ultrasonography have been used for detecting carotid artery stenosis. Doppler ultrasonography has unique physical properties. The operator should be familiar with the physics and other parameters of Doppler ultrasonography to perform optimal Doppler ultrasonography studies.

  8. Measurement uncertainty in pulmonary vascular input impedance and characteristic impedance estimated from pulsed-wave Doppler ultrasound and pressure: clinical studies on 57 pediatric patients.

    Science.gov (United States)

    Tian, Lian; Hunter, Kendall S; Kirby, K Scott; Ivy, D Dunbar; Shandas, Robin

    2010-06-01

    Pulmonary vascular input impedance better characterizes right ventricular (RV) afterload and disease outcomes in pulmonary hypertension compared to the standard clinical diagnostic, pulmonary vascular resistance (PVR). Early efforts to measure impedance were not routine, involving open-chest measurement. Recently, the use of pulsed-wave (PW) Doppler-measured velocity to non-invasively estimate instantaneous flow has made impedance measurement more practical. One critical concern remains with clinical use: the measurement uncertainty, especially since previous studies only incorporated random error. This study utilized data from a large pediatric patient population to comprehensively examine the systematic and random error contributions to the total impedance uncertainty and determined the least error prone methodology to compute impedance from among four different methods. We found that the systematic error contributes greatly to the total uncertainty and that one of the four methods had significantly smaller propagated uncertainty; however, even when this best method is used, the uncertainty can be large for input impedance at high harmonics and for the characteristic impedance modulus. Finally, we found that uncertainty in impedance between normotensive and hypertensive patient groups displays no significant difference. It is concluded that clinical impedance measurement would be most improved by advancements in instrumentation, and the best computation method is proposed for future clinical use of the input impedance.

  9. The radar signal simulation based on the analysis of Pulse-Doppler radar for digital signal processing implementation in the Matlab environment

    Directory of Open Access Journals (Sweden)

    Yu. Yu. Reutskaya

    2015-03-01

    Full Text Available Introduction. The complexity of modern radar (RLS due to their versatility and the need to adapt to the interference situation is constantly changed. The models to test the basic ideas to be implemented in the radar are required. It is important to consider the main stages of the simulation of the radar signal based on the analysis of radar operation. Problem statement. The creation of a universal analytical model to build a radar signal in Matlab is considered. Theoretical results. Stages and results of the radar signal simulation are presented and based on the analysis of pulseDoppler radar. Basic analytical relations ofthe task are given. Features of simulation when signals of additive fluctuation noise and clutter together with the echo target signals arrive are considered. Conclusion. As a result of analysis of radar interference conditions on the basis of existing relations an optimum variant model of radar signal in Matlab environment is reached. This is the basis for further evaluation of the digital processing effectiveness of the radar signal to background noise and interference (clutter, namely to determine the distance to targets and target’s speeds. . The main advantages of the Mellin transform using for recognizing signals at different scales are presented is conclusions.

  10. Relationship between the rheological properties of thickener solutions and their velocity through the pharynx as measured by the ultrasonic pulse Doppler method.

    Science.gov (United States)

    Tashiro, Akiko; Hasegawa, Atsuko; Kohyama, Kaoru; Kumagai, Hitomi; Kumagai, Hitoshi

    2010-01-01

    The dependence of the dynamic viscoelastic parameters of carboxymethylcellulose (CMC), xanthan gum, and guar gum solutions on the angular frequency (omega) was compared with that of their viscosity (mu) on the shear rate (gamma). In addition, the effect of these rheological properties on the maximum velocity through the pharynx, V(max), as measured by the ultrasonic pulse Doppler method, was investigated. The CMC and guar gum solutions examined were taken as a dilute solution and a true polymer solution, respectively. The xanthan gum solution was taken as a weak gel above 0.5% and a true polymer solution below 0.2%. The maximum velocity, V(max), of the thickener solutions correlated well with mu, the dynamic viscosity eta', and the complex viscosity eta(*), especially those measured at gamma or omega of 20-30 s(-1) (or rad/s) and above, suggesting that mu, eta', and eta(*) are suitable indexes for care foods of the liquid type for dysphagic patients.

  11. Five years use of Pulse Doppler RADAR-utechnology in debris-flows monitoring - experience at three test sites so far

    Science.gov (United States)

    Koschuch, Richard; Brauner, Michael; Hu, Kaiheng; Hübl, Johannes

    2016-04-01

    Automatic monitoring of alpine mass movement is a major challenge in dealing with natural hazards. The presented research project shows a new approach in measurment and alarming technology for water level changes an debris flow by using a high-frequency Pulse Doppler RADAR. The detection system was implemented on 3 places (2 in Tirol/Austria within the monitoring systems of the IAN/BOKU; 1 in Dongchuan/China within the monitoring systems of the IMHE/Chinese Academy of Science) in order to prove the applicability of the RADAR in monitoring torrential activities (e.g. debris-flows, mudflows, flash floods, etc.). The main objective is to illustrate the principles and the potential of an innovative RADAR system and its versatility as an automatic detection system for fast (> 1 km/h - 300 km/h) alpine mass movements of any kind. The high frequency RADAR device was already successfully tested for snow avalanches in Sedrun/Switzerland (Lussi et al., 2012), in Ischgl/Austria (Kogelnig et al., 2012). The experience and the data of the five year showed the enormous potential of the presented RADAR technology in use as an independent warning and monitoring system in the field of natural hazard. We have been able to measure water level changes, surface velocities and several debris flows and can compare this data with the other installed systems.

  12. Pulsed Wave Doppler Ultrasound Is Useful to Assess Vasomotor Response in Patients with Multiple System Atrophy and Well Correlated with Tilt Table Study

    Directory of Open Access Journals (Sweden)

    Ke-Vin Chang

    2012-01-01

    Full Text Available The study aim was to assess sympathetic vasomotor response (SVR by using pulsed wave Doppler (PWD ultrasound in patients with multiple system atrophy (MSA and correlate with the tilt table study. We recruited 18 male patients and 10 healthy men as controls. The SVR of the radial artery was evaluated by PWD, using inspiratory cough as a provocative maneuver. The response to head-up tilt was studied by a tilt table with simultaneous heart rate and blood pressure recording. The hemodynamic variables were compared between groups, and were examined by correlation analysis. Regarding SVR, MSA patients exhibited a prolonged latency and less heart rate acceleration following inspiratory cough. Compared with the tilt table test, the elevation of heart rate upon SVR was positively correlated to the increase of heart rate after head-up tilt. The correlation analysis indicated that the magnitude of blood pressure drop from supine to upright was positively associated with the SVR latency but negatively correlated with the heart rate changes upon SVR. The present study demonstrated that blunted heart rate response might explain MSA's vulnerability to postural challenge. PWD may be used to predict cardiovascular response to orthostatic stress upon head-up tilt in MSA patients.

  13. Automatic extraction of disease-specific features from Doppler images

    Science.gov (United States)

    Negahdar, Mohammadreza; Moradi, Mehdi; Parajuli, Nripesh; Syeda-Mahmood, Tanveer

    2017-03-01

    Flow Doppler imaging is widely used by clinicians to detect diseases of the valves. In particular, continuous wave (CW) Doppler mode scan is routinely done during echocardiography and shows Doppler signal traces over multiple heart cycles. Traditionally, echocardiographers have manually traced such velocity envelopes to extract measurements such as decay time and pressure gradient which are then matched to normal and abnormal values based on clinical guidelines. In this paper, we present a fully automatic approach to deriving these measurements for aortic stenosis retrospectively from echocardiography videos. Comparison of our method with measurements made by echocardiographers shows large agreement as well as identification of new cases missed by echocardiographers.

  14. Radar Doppler Processing with Nonuniform Sampling.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-07-01

    Conventional signal processing to estimate radar Doppler frequency often assumes uniform pulse/sample spacing. This is for the convenience of t he processing. More recent performance enhancements in processor capability allow optimally processing nonuniform pulse/sample spacing, thereby overcoming some of the baggage that attends uniform sampling, such as Doppler ambiguity and SNR losses due to sidelobe control measures.

  15. Advanced Three-Dimensional Echocardiography

    NARCIS (Netherlands)

    B. Ren (Ben)

    2014-01-01

    markdownabstract__Abstract__ During the development of echocardiography, 3D echocardiography imaging represents a major innovation in cardiovascular ultrasound (Figure 1). Advancements in computer and transducer technologies permit real-time 3D acquisition and presentation of cardiac

  16. Color Doppler echocardiography observing theraph of triscuspid valve regurgitation in foetus during middle and late pregnancy by normobaric oxygen%彩色多普勒超声心动图对常压氧治疗中晚期妊娠胎儿三尖瓣反流的疗效观察

    Institute of Scientific and Technical Information of China (English)

    郭子玉; 梁玉玲; 刘美娟

    2010-01-01

    Objective To analyze the curative effect of normobafic oxygen on the treatment of triscuspid valve regurgitation in foetus during middle and late pregnancy by Color Doppler echocardiography.Methods 245 patients with triscuspid valve regurgitation in foetus during middle and late pregnancy were divided into two groups,105 cases cured by low-flow、low concentrations、normobaric oxygen through nasal oxygen tube were me3sured by echocardiography,And 140 untreated patients were selected as the contrast group.Results 71 foetus triscuspid regnrgiration disappeared after treating by normobaric oxygen,10 cases impmved,the cure rate was 67.62%,the improvement rate was 9.52%,the effective rate of the treatment was 77.14%.there was no discrepancy between the treated group and control group(P>0.05).Conclusion Triscuspid regurgitation could not disappear and light earlier by low-flow、low concentrations、normobaric oxygen through nasal oxygen tube,which was recovered with normobaric oxygen on the treatment of certain fetul primary affection.%目的 利用彩色多普勒超声心动图分析常压氧治疗中晚期妊娠胎儿三尖瓣返流的疗效.方法 应用彩色多普勒超声心动图观察低流量、低浓度、常压下鼻导管吸氧疗法治疗中晚期妊娠胎儿三尖瓣返流105例前后的变化情况,并与140例胎儿三尖瓣返流未治疗组进行对照.结果 105例中71例经常压氧治疗后胎儿三尖瓣返流消失,10例好转.治愈率为67.62%,好转率为9.52%.有效率为77.14%,与对照组比较差异无显著性(P>0.05).结论 低流量、低浓度、常压下鼻导管吸氧疗法不能够使三尖瓣返流提前消失或好转,而吸氧可以治疗胎儿时期某些原发病,随着原发病的治愈,三尖瓣反流亦消失.

  17. Clinical Stress Echocardiography

    NARCIS (Netherlands)

    S.E. Karagiannis

    2007-01-01

    textabstractTwo-dimensional echocardiography is a commonly used non-invasive method for the assessment of left ventricular function. It provides precise information on both global and segmental myocardial function by displaying endocardial motion and wall thickening. Dobutamine stress echocardiograp

  18. Assessment of Regional Myocardial Displacement via Spectral Tissue Doppler Compared with Color Tissue Tracking

    Directory of Open Access Journals (Sweden)

    Zahra Ojaghi-Haghighi

    2008-12-01

    Full Text Available Background: The recent developments in tissue Doppler imaging (TDI now more than ever permit the quantification of the myocardial function. In the current systems, tissue tracking or displacement curves are generated from color tissue Doppler data through the instantaneous temporal integral of velocity-time curves. Methods: The purpose of the present study was to assess regional myocardial displacement via spectral TDI. Maximum myocardial velocities were extracted from spectral pulsed tissue Doppler images using a developed computer program and were integrated throughout the cardiac cycle. Spectral tissue Doppler echocardiography was performed to evaluate longitudinal and radial functions in 20 healthy men, and the calculated end-systolic displacements were subsequently compared with the displacements measured from the same areas via color tissue tracking. Results: According to the Bland-Altman analysis between spectral tissue tracking and color tissue tracking, the significant arithmetic mean was 7.34 mm with SD mean differences of ±2.24 mm in all of the evaluated segments. Despite significant differences (p<0.001, there was a good significant correlation between the two methods (r=0.79, p<0.001. Conclusion: A verification study showed that the proposed approach had the ability to assess regional myocardial displacement using spectral TDI, which can be used in a wider range of equipment than is currently possible.

  19. Transcranial power M-mode Doppler ultrasound for diagnosis of patent foramen ovale

    Science.gov (United States)

    Moehring, Mark; Spencer, Merrill

    2005-04-01

    Patent foramen ovale (PFO) is a right-to-left shunt (RLS) which communicates blood from the right to left atrium of the heart. PFO has been associated with stroke and, more recently, with migraine headache. Diagnosis of RLS can be accomplished effectively with transcranial power M-mode Doppler ultrasound (PMD). PMD is a modality which can be performed without the sedation required by the more invasive diagnostic technique using transesophageal echocardiography. PMD for this application consists of 2 MHz pulse Doppler ultrasound with placement of sample gates at 2 mm intervals along the single-transducer beam axis, and 8 kHz pulse repetition rate (PMD100M, Spencer Technologies). Doppler power versus depth is constructed every 4ms, using 33 sample gates. Bubble microemboli injected in the venous system and moving across a PFO present as high intensity tracks on a PMD image, as emboli transit from the heart to the brain and through the observed cerebral vasculature. Use of PMD in this context has been reported in the clinical literature [M. P. Spencer, M. A. Moehring, J. Jesurum et al, J. Neuroimaging 14, 342-349 (2004)]. This talk surveys the basic technical features of PMD for sensing PFO-related showers of bubble microemboli, and how these features provide clues to the severity of PFO.

  20. Comparisons between PW Doppler system and enhanced FM Doppler system

    DEFF Research Database (Denmark)

    Wilhjelm, Jens E.; Pedersen, P. C.

    1995-01-01

    This paper presents a new implementation of an echo-ranging FM Doppler system with improved performance, relative to the FM Doppler system reported previously. The use of long sweeps provides a significant reduction in peak to average power ratio compared to pulsed wave (PW) emission. A PW Doppler...... system exploits the direct relationship between arrival time of the received signal and range from the transducer. In the FM Doppler systems, a similar relationship exists in the spectral domain of the demodulated received signals, so that range is represented by frequency. Thus, a shift in location...... of moving scatterers between consecutive emissions corresponds to a frequency shift in the spectral signature. The improvement relative to the earlier version of the FM Doppler system is attained by utilizing cross-correlation of real spectra rather than of magnitude spectra for assessing flow velocity...

  1. Clinical significance of left ventricular false tendons diagnosed by color Doppler echocardiography for pilot%彩色多普勒超声心动图诊断飞行员左室假腱索及其临床意义

    Institute of Scientific and Technical Information of China (English)

    郝建华; 郭辉; 胡文莉; 蒋毅; 周锡江

    2010-01-01

    Objective To study the clinical significance of diagnosing pilot's left ventricular false tendons (LVFT) by color Doppler echocardiography.Methods The case history of 934 pilots who were examined by color Doppler echocardiography in recent 8 years was reviewed.Pilots were grouped by judging if the LVFT was diagnosed.The detection rate of premature ventricular contraction and the change of T wave or S-T, as well as age were compared between LVFT group and healthy group.Results There were 98 cases of LVFT picked out of 934 pilots; the detection rate was 10.49%.Masculine of premature ventricular contraction and the change of T wave or S-T in LVFT group showed significant difference (x2=97.71 and 70.16, P<0.01) but for age (t=1.479, P>0.05).Conclusions LVFT shows certain relationship with premature ventricular contraction and the change of T wave or S-T except the reason of organic heart disease.Even LEFT taken as a kind of normal anatomical variation but it has the possibility of evoking premature ventricular contraction after all.Caring LVFT is suggested in medical identification of pilot.%目的 探讨飞行员左室假腱索的彩色多普勒超声心动图诊断及其临床意义.方法 对我院近8年来进行彩色多普勒超声心动图检查的934例男性飞行员资料进行分析,按是否存在左室假腱索对飞行员进行分组,比较两组室性早搏、T波或ST-T改变的检出率及年龄.结果 934例飞行员发现有左室假腱索98例,检出率10.49%,无假腱索者836例(占89.51%).左室假腱索组与无假腱索组飞行员所出现的室性早搏阳性率和T波或ST-T改变阳性率组间比较,差异有统计学意义(x2=97.71、70.16,P<0.01),两组年龄比较无显著差异(t=1.479,P>0.05).结论 除外器质性心脏病,飞行员左室假腱索与临床出现的室性早搏和T波或ST-T改变有一定的关联性,左室假腱索的检出对飞行员的医学健康鉴定有一定的诊断价值和临床意义.

  2. Biplane transesophageal echocardiography in the normal cat.

    Science.gov (United States)

    Kienle, R D; Thomas, W P; Rishniw, M

    1997-01-01

    Eight healthy, adult cats were examined with biplane transesophageal echocardiography (TEE). Cats were sedated with a combination of diazepam and propofol and were examined using a 5 mm x 80 cm pediatric biplane TEE probe. Consistent images were obtained at three imaging depths within the esophagus. The caudal position provided satisfactory short-axis images of the left ventricle and heart base. The middle position provided the best long-axis views of the left atrium, left ventricle, and aorta and allowed Doppler examination of transmitral left ventricular inflow. The cranial position provided satisfactory imaging of the aorta and pulmonary artery and allowed Doppler examination of right ventricular and left ventricular outflow. Biplane TEE provides an additional method of imaging the feline heart which is complimentary to other imaging techniques and the images obtained were similar to those reported for dogs. Although TEE offers a slight advantage over transthorcic imaging for Doppler examination, the quality of the images of heart base structures was not as consistently superior to transthoracic images in cats as reported in dogs.

  3. The best of 2005 in echocardiography back from EuroEcho 9 – Florence, Italy

    Directory of Open Access Journals (Sweden)

    Sicari Rosa

    2006-02-01

    Full Text Available Abstract The ninth edition of the congress of the European Association of Echocardiography (EAE (former working group of Echocardiography held in Florence has just finished with a great success of participant attendance (2.842 and abstract submissions. Hot topics at EuroEcho 9 were: 1-live 3-dimensional echocardiography and surgical decision making; in pediatric cardiology; in resynchronization therapy 2- stress echocardiography beyond wall motion: from valve diseases to contractility to coronary flow reserve to diastolic function; 3- pulmonary cardiogenic interstitial thickening recognized by ultrasonic lung comets; 4- the "proven clinical inefficacy" of the many technologies sold as breakthrough: color kinesis, tissue characterization, strain rate, tissue Doppler, applied to stress echocardiography.

  4. Transesophageal echocardiography: Instrumentation and system controls

    Directory of Open Access Journals (Sweden)

    Mahesh Prabhu

    2012-01-01

    Full Text Available Transesophageal echocardiography (TEE is a semi-invasive, monitoring and diagnostic tool, which is used in the perioperative management of cardiac surgical and hemodynamically unstable patients. The low degree of invasiveness and the capacity to visualize and assimilate dynamic information that can change the course of the patient management is an important advantage of TEE. Although TEE is reliable, comprehensive, credible, and cost-effective, it must be performed by a trained echocardiographer who understands the indications and the potential complications of the procedure, and has the ability to achieve proper acquisition and interpretation of the echocardiographic data. Adequate knowledge of the physics of ultrasound and the TEE machine controls is imperative to optimize image quality, reduce artifacts, and prevent misinterpretation of diagnosis. Two-dimensional (2D and Motion (M mode imaging are used for obtaining anatomical information, while Doppler and Color Flow imaging are used for information on blood flow. 3D technology enables us to view the cardiac structures from different perspectives. Despite the recent advances of 3D TEE, a sharp, optimized 2D image is pivotal for the reconstruction. This article describes the relevant underlying physical principles of ultrasound and focuses on a systematic approach to instrumentation and use of controls in the practical use of transesophageal echocardiography.

  5. Doppler Tomography

    CERN Document Server

    Marsh, T R

    2000-01-01

    I review the method of Doppler tomography which translates binary-star line profiles taken at a series of orbital phases into a distribution of emission over the binary. I begin with a discussion of the basic principles behind Doppler tomography, including a comparison of the relative merits of maximum entropy regularisation versus filtered back-projection for implementing the inversion. Following this I discuss the issue of noise in Doppler images and possible methods for coping with it. Then I move on to look at the results of Doppler Tomography applied to cataclysmic variable stars. Outstanding successes to date are the discovery of two-arm spiral shocks in cataclysmic variable accretion discs and the probing of the stream/magnetospheric interaction in magnetic cataclysmic variable stars. Doppler tomography has also told us much about the stream/disc interaction in non-magnetic systems and the irradiation of the secondary star in all systems. The latter indirectly reveals such effects as shadowing by the a...

  6. Retinopathy is associated with impaired myocardial function assessed by advanced echocardiography in type 1 diabetes patients – The Thousand & 1 Study

    DEFF Research Database (Denmark)

    Nouhravesh, Nina; Andersen, Henrik U; Jensen, Jan S

    2016-01-01

    AIMS: Retinopathy and heart disease in Type 1 Diabetes Mellitus (Type 1 DM) may be associated; however previous results have been conflicting. Tissue Doppler Imaging (TDI) and speckle-tracking echocardiography (STE) quantify myocardial function not assessable by conventional echocardiography. We...

  7. New concepts in echocardiography

    NARCIS (Netherlands)

    N. Bom (Klaas)

    1972-01-01

    textabstractIf short pulses of high frequency sound are transmitted through the heart, discontinuities in the tissues will produce reflected sound waves or "echoes". There wil! be a delay between a pulse transmission and the arrival of a correspond·mg echo. Together with knowledge of sound velocity

  8. Assessment of right ventricular systolic function by tissue Doppler echocardiography

    DEFF Research Database (Denmark)

    Kjærgaard, Jesper

    2012-01-01

    in these patients [IV and V]. Regional deformation of the RV free wall has significant prognostic importance in a population suspected of first non-massive pulmonary embolism, and is significantly associated with adverse events in patients with proven pulmonary embolism, however, it does not add to the information...

  9. Role of echocardiography in diagnosis of pulmonary hypertension

    Directory of Open Access Journals (Sweden)

    Srbinovska Kostovska Elizabeta

    2013-07-01

    Full Text Available Pulmonary hypertension (PH is a progressive process that leads to right ventricular (RV overload, hypertrophy, dilatation and RV failure. In cases with chronic heart failure, this condition is associated with more severe symptoms and worse outcomes.Transthoracic echocardiography can give several parameters which correlate with right heart haemodynamics, and should be performed in a case of suspected PH. Several parameters are important for estimation of the RV function, which can be reason for poor outcome: right atrial and ventricular dimensions and volumes, functional area changes, tricuspid annular plane systolic excursion (TAPSE, myocardial performance index, infe- rior vena cava size and collapsibility, S velocity estimated by Tissue Doppler Imaging, and additional information obtained from the advance echocardiograpic techniques, like strain, strain rate, three-dimensional echocardiography. Estimation of PH based on Doppler echo- cardiography measurements is not suitable for screening of mild, asymptomatic PH. Echocardiography can be recommended as a screening tool for specific diseases, follow up PH, and assessment when right heart catheterization is indicated.

  10. Doppler imaging

    Energy Technology Data Exchange (ETDEWEB)

    Piskunov, N [Department of Physics and Astronomy, Uppsala University, Box 515, S-75120 Uppsala (Sweden)], E-mail: piskunov@fysast.uu.se

    2008-12-15

    In this paper, I present a short review of the history and modern status of Doppler imaging techniques, highlighting their dependence on the knowledge of the fundamental stellar parameters, the quality of stellar atmospheric models and the accuracy of spectral synthesis.

  11. Effect of preload alternations on a new Doppler echocardiographic index of combined systolic and diastolic performance

    DEFF Research Database (Denmark)

    Møller, J E; Poulsen, S H; Egstrup, K

    1999-01-01

    The objective of the study was to assess the effect of preload alternations on a nongeometric Doppler index of combined systolic and diastolic myocardial performance (MPI). Doppler echocardiography was performed during Valsalva maneuver, passive leg lifting, and after sublingual administration of...

  12. A maximum likelihood approach to diffeomorphic speckle tracking for 3D strain estimation in echocardiography

    NARCIS (Netherlands)

    A.H. Curiale (Ariel H.); G. Vegas-Sanchez-Ferrero (Gonzalo); J.G. Bosch (Hans); S. Aja-Fernández (Santiago)

    2015-01-01

    textabstractThe strain and strain-rate measures are commonly used for the analysis and assessment of regional myocardial function. In echocardiography (EC), the strain analysis became possible using Tissue Doppler Imaging (TDI). Unfortunately, this modality shows an important limitation: the angle

  13. A maximum likelihood approach to diffeomorphic speckle tracking for 3D strain estimation in echocardiography

    NARCIS (Netherlands)

    A.H. Curiale (Ariel H.); G. Vegas-Sanchez-Ferrero (Gonzalo); J.G. Bosch (Johan); S. Aja-Fernández (Santiago)

    2015-01-01

    textabstractThe strain and strain-rate measures are commonly used for the analysis and assessment of regional myocardial function. In echocardiography (EC), the strain analysis became possible using Tissue Doppler Imaging (TDI). Unfortunately, this modality shows an important limitation: the angle b

  14. THE DIAGNOSTIC VALUE OF PULSED WAVE TISSUE DOPPLER IMAGING IN ASYMPTOMATIC BETA- THALASSEMIA MAJOR CHILDREN AND YOUNG ADULTS ; RELATION TO CHEMICAL BIOMARKERS OF LEFT VENTRICULAR FUNCTION AND IRON OVERLOAD .

    Directory of Open Access Journals (Sweden)

    Seham Ragab

    2015-08-01

    Full Text Available Background: Cardiac iron toxicity is the leading cause of death among  β-halassaemia major (TM  patients.  Once  heart failure becomes overt , it will be  difficult to reverse . Objectives: To investigate non overt cardiac dysfunctions  in TM patients using  pulsed wave Tissue Doppler  Imaging (TD I and its relation to the iron overload and brain natruritic peptide (BNP. Methods: Thorough  clinical , conventional echo and  pulsed  wave TDI  parameters were compared between  asymtomatic 25 β-TM  patients  and 20 age and gender matched individuals. Serum ferritin and plasma BNP  levels were assayed by  ELISA .  Results: TM patients had significant higher mitral inflow early diastolic (E wave and  non significant other conventional echo  parameters. Pulsed wave TDI revealed systolic and diastolic dysfunctions in the form of significant higher  isovolumetric contraction time (ICT , ejection time ( E T and  isovolumetric relaxation time (IRT with significantly lower  mitral annulus  early diastolic velocity E` (12.07 ±2.06 vs 15.04±2.65 ,P= 0.003  in patients compared to  controls. Plasma BNP was higher in patients compared to the controls.  Plasma BNP and serum ferritin had significant correlation with each other and with pulsed wave conventional and TDI indices of systolic and diastolic functions.  Patients with E/E` ≥ 8 had  significant higher  serum ferritin  and plasma BNP levels compared to those with E/E` ratio < 8 without difference in Hb levels .Conclusion:  Pulsed wave TDI  is an  important diagnostic tool for latent cardiac dysfunction in iron loaded TM patients and is related to iron overload and BNP .

  15. Study on imaging characteristics of color Doppler echocardiography on adult mirror image dextrocardia and deformity%成人镜像右位心及合并畸形彩色多普勒超声心动图特征研究

    Institute of Scientific and Technical Information of China (English)

    侯传举; 邹苏娅; 邓东安; 朱鲜阳; 韩秀敏; 刘剑立; 胡斌; 王巧玲

    2011-01-01

    目的:探寻成人镜像右位心及合并畸形彩色多普勒超声心动图(CDE)特征.方法:应用CDE检查31例成人镜像右位心及合并畸形,寻找CDE特征,所有病例均经心导管对照,21例手术证实.结果:根据CDE特征对29例做出正确诊断,诊断准确率93.5%,误诊2例.成人镜像右位心及合并畸形CDE特征明显;①成人镜像右位心合并11种先天性心脏病,其中ILL型右心室双出口(22.6%)、IDD型矫正性大动脉转位(19.4%)和法乐四联症(19.4%)多见,心室双人口(12.9%)和室间隔缺损(6.5%)少见,两腔心、二尖瓣闭锁、三尖瓣闭锁、全肺静脉异位引流、孤立性双腔右心室和孤立性二尖瓣裂隙(各3.2%)更少见;②成人镜像右位心无论合并那种先天性心脏病均为心房反位;③成人镜像右位心合并右心室双出口大动脉均为左转位;合并矫正性大动脉转位大动脉均为右转位;(4)成人镜像右位心合并肺动脉狭窄(93.5%)多见,肺动脉高压(6.5%)少见.肺动脉狭窄时,彩色多普勒血流显像显示过肺动脉五彩镶嵌射流束血流信号;⑤合并房间隔缺损和室间隔缺损时,彩色多普勒血流显像显示过房间隔或室间隔左向右或双向五彩镶嵌分流束血流信号.结论:成人镜像右位心及合并畸形CDE特征明显,应用CDE对成人镜像右位心及合并畸形可做出正确诊断,但检查者必须熟练掌握本病解剖.在探查手法上与正常位心脏明显不同,检查前阅读X线正位胸片对CDE正确诊断有帮助,并可提高检查效率.%Objective:To explore the characteristics of color Doppler echocardiography (CDE) adult mirror image dextrocardia and deformiry. Methods Thirty-one patients with adult mirror image dextrocardia and deformity were examined by CDE. All cases with mirror image dextrocardia and deformity underwent angiocardiography examination after CDE, twenty-one cases were proved by surgical operations. Results: Twenty-nine cases were diagnosed

  16. Pacing stress echocardiography

    Directory of Open Access Journals (Sweden)

    Agrusta Marco

    2005-12-01

    Full Text Available Abstract Background High-rate pacing is a valid stress test to be used in conjunction with echocardiography; it is independent of physical exercise and does not require drug administration. There are two main applications of pacing stress in the echo lab: the noninvasive detection of coronary artery disease through induction of a regional transient dysfunction; and the assessment of contractile reserve through peak systolic pressure/ end-systolic volume relationship at increasing heart rates to assess global left ventricular contractility. Methods The pathophysiologic rationale of pacing stress for noninvasive detection of coronary artery disease is obvious, with the stress determined by a controlled increase in heart rate, which is a major determinant of myocardial oxygen demand, and thereby tachycardia may exceed a fixed coronary flow reserve in the presence of hemodynamically significant coronary artery disease. The use of pacing stress echo to assess left ventricular contractile reserve is less established, but promising. Positive inotropic interventions are mirrored by smaller end-systolic volumes and higher end-systolic pressures. An increased heart rate progressively increases the force of ventricular contraction (Bowditch treppe or staircase phenomenon. To build the force-frequency relationship, the force is determined at different heart rate steps as the ratio of the systolic pressure (cuff sphygmomanometer/end-systolic volume index (biplane Simpson rule. The heart rate is determined from ECG. Conclusion Two-dimensional echocardiography during pacing is a useful tool in the detection of coronary artery disease. Because of its safety and ease of repeatability noninvasive pacing stress echo can be the first-line stress test in patients with permanent pacemaker. The force-frequency can be defined as up- sloping (normal when the peak stress pacing systolic pressure/end-systolic volume index is higher than baseline and intermediate stress

  17. Velocity-aligned Doppler spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Z.; Koplitz, B.; Wittig, C.

    1989-03-01

    The technique of velocity-aligned Doppler spectrosocopy (VADS) is presented and discussed. For photolysis/probe experiments with pulsed initiation, VADS can yield Doppler profiles for nascent photofragments that allow detailed center-of-mass (c.m.) kinetic energy distributions to be extracted. When compared with traditional forms of Doppler spectroscopy, the improvement in kinetic energy resolution is dramatic. Changes in the measured profiles are a consequence of spatial discrimination (i.e., focused and overlapping photolysis and probe beams) and delayed observation. These factors result in the selective detection of species whose velocities are aligned with the wave vector of the probe radiation k/sub pr/, thus revealing the speed distribution along k/sub pr/ rather than the distribution of nascent velocity components projected upon this direction. Mathematical details of the procedure used to model VADS are given, and experimental illustrations for HI, H/sub 2/S, and NH/sub 3/ photodissociation are presented. In these examples, pulsed photodissociation produces H atoms that are detected by sequential two-photon, two-frequency ionization via Lyman-..cap alpha.. with a pulsed laser (121.6+364.7 nm), and measuring the Lyman-..cap alpha.. Doppler profile as a function of probe delay reveals both internal and c.m. kinetic energy distributions for the photofragments. Strengths and weaknesses of VADS as a tool for investigating photofragmentation phenomena are also discussed.

  18. Pulse Wave Doppler Blood Flow Measurement System Based on DSP%基于DSP的脉冲多普勒血流测量系统

    Institute of Scientific and Technical Information of China (English)

    智再新; 陈真诚; 朱健铭

    2013-01-01

    Objective To enhance the glucose detection precision for the diagnosis and treatment of vascular diseases. Methods With DSP as the control unit, a Doppler probe with the transceiver was used to develop a blood flow measurement system. Based on Doppler effect, the system acquired ultrasonic echo signals, and then determined the blood flow rate through Doppler frequency tolerance. Results By acquiring and analyzing echo signals, the system could detect the blood flow with a desired depth. Conclusion The blood flow measurement system, with simplified circuit and enhanced precision, is valuable for the clinical diagnosis of the diabetes and the development of other portable ultrasonic devices.%目的:提高血糖无创检测的精度,以利于诊断和治疗血管疾病.方法:以DSP为控制核心,采用收发一体的多普勒探头,研制一种血流测量系统.该系统基于多普勒效应,采集超声回波信号,通过多普勒频差计算血流速度.结果:通过采集与分析回波信号,该系统可以对预定目标深度的血流进行检测.结论:该系统极大简化了电路规模,提高了检测精度,对糖尿病的临床诊断和其他便携超声仪器的研制都具有重要的实用价值.

  19. Evaluation of diastolic function in hypertensive using echocardiography

    Directory of Open Access Journals (Sweden)

    Yamini Lavanya

    2015-09-01

    Results: The trans-mitral inflow parameters on Doppler echocardiography such as E wave deceleration time (DT, isovolumetric relaxation time (IVRT and early to late transmitral peak flow velocities ratio (E/A were significantly different in hypertensive subjects on treatment having normal ejection fraction, when compared to normotensive subjects. We observed a decrease in E/A ratio and increase in DT, IVRT with hypertension. Conclusions: From the present study it can be concluded that hypertension is significantly associated with diastolic dysfunction of heart, even in subjects with normal systolic function. [Int J Res Med Sci 2015; 3(9.000: 2274-2279

  20. Three-dimensional transesophageal echocardiography: Principles and clinical applications

    Directory of Open Access Journals (Sweden)

    Annette Vegas

    2016-01-01

    Full Text Available A basic understanding of evolving 3D technology enables the echocardiographer to master the new skills necessary to acquire, manipulate, and interpret 3D datasets. Single button activation of specific 3D imaging modes for both TEE and transthoracic echocardiography (TTE matrix array probes include (a live, (b zoom, (c full volume (FV, and (d color Doppler FV. Evaluation of regional LV wall motion by RT 3D TEE is based on a change in LV chamber subvolume over time from altered segmental myocardial contractility. Unlike standard 2D TEE, there is no direct measurement of myocardial thickening or displacement of individual segments.

  1. Evaluation of cardiac longitudinal systolic function in patients with heart transplant using two dimensional speckle tracking echocardiography and tissue Doppler imaging%二维斑点追踪及组织多普勒技术评价移植心脏纵向收缩功能的临床研究

    Institute of Scientific and Technical Information of China (English)

    李政; 潘翠珍; 舒先红; 陈昊; 王春生

    2014-01-01

    目的 应用二维斑点追踪技术及组织多普勒技术分别评价移植心脏左、右室纵向收缩功能.方法 56例心脏移植患者,根据心内膜心肌活检及长期临床随访结果分为无排异组(A组)和排异组(B组),随机入选36例健康志愿者归入C组,测量左室射血分数(LVEF)、肺动脉收缩压、三尖瓣瓣环位移(TAPSE)和三尖瓣瓣环收缩期速度(TA-S')等指标.应用Qlab 9.0软件分析获得左室整体纵向应变值(global longitudinal strain,GLS).结果 B组较C组LVEF降低(P<0.01).三组间GLS、TAPSE及TA-S'值比较差异均有统计学意义(P均<0.01),B组<A组<C组;GLS与LVEF、TAPSE、TA-S'有较好的负相关性(r分别为-0.64,-0.69,-0.71,P均<0.01).结论 心脏移植患者左、右室纵向收缩功能均有不同程度降低.%Objective To investigate longitudinal systolic function of transplanted heart using two dimensional speckle tracking echocardiography and tissue Doppler imaging.Methods 56 consecutive patients with heart transplant were recruited,according to myocardial biopsy and 1 year's follow up,they were divided into non-rejection group (group A) and rejection group (group B).36 healthy controls (group C) were also randomly recruited.Left ventricular ejection fraction (LVEF),pulmonary arterial systolic pressure,tricuspid annular plane systolic excursion (TAPSE),tricuspid annular plane systolic velocity (TAS') and global longitudinal strain (GLS) were calculated via Qlab 9.0 analysis software offline.Results Compared with group C,LVEF was reduced in group B (P <0.01).Differences of GLS,TAPSE,and TA-S' among groups were all statistically significant (P <0.01),group B<group A< group C.LVEF,TAPSE and TA-S' were correlated with GLS (r =-0.64,r =-0.69,r =-0.71 ; all P < 0.01).Conclusions Left and right ventricles were a functional unity,the systolic function of which was impaired in patients with heart transplant.

  2. Staggered Multiple-PRF Ultrafast Color Doppler.

    Science.gov (United States)

    Posada, Daniel; Poree, Jonathan; Pellissier, Arnaud; Chayer, Boris; Tournoux, Francois; Cloutier, Guy; Garcia, Damien

    2016-06-01

    Color Doppler imaging is an established pulsed ultrasound technique to visualize blood flow non-invasively. High-frame-rate (ultrafast) color Doppler, by emissions of plane or circular wavefronts, allows severalfold increase in frame rates. Conventional and ultrafast color Doppler are both limited by the range-velocity dilemma, which may result in velocity folding (aliasing) for large depths and/or large velocities. We investigated multiple pulse-repetition-frequency (PRF) emissions arranged in a series of staggered intervals to remove aliasing in ultrafast color Doppler. Staggered PRF is an emission process where time delays between successive pulse transmissions change in an alternating way. We tested staggered dual- and triple-PRF ultrafast color Doppler, 1) in vitro in a spinning disc and a free jet flow, and 2) in vivo in a human left ventricle. The in vitro results showed that the Nyquist velocity could be extended to up to 6 times the conventional limit. We found coefficients of determination r(2) ≥ 0.98 between the de-aliased and ground-truth velocities. Consistent de-aliased Doppler images were also obtained in the human left heart. Our results demonstrate that staggered multiple-PRF ultrafast color Doppler is efficient for high-velocity high-frame-rate blood flow imaging. This is particularly relevant for new developments in ultrasound imaging relying on accurate velocity measurements.

  3. Doppler echo evaluation of pulmonary venous-left atrial pressure gradients: human and numerical model studies

    Science.gov (United States)

    Firstenberg, M. S.; Greenberg, N. L.; Smedira, N. G.; Prior, D. L.; Scalia, G. M.; Thomas, J. D.; Garcia, M. J.

    2000-01-01

    The simplified Bernoulli equation relates fluid convective energy derived from flow velocities to a pressure gradient and is commonly used in clinical echocardiography to determine pressure differences across stenotic orifices. Its application to pulmonary venous flow has not been described in humans. Twelve patients undergoing cardiac surgery had simultaneous high-fidelity pulmonary venous and left atrial pressure measurements and pulmonary venous pulsed Doppler echocardiography performed. Convective gradients for the systolic (S), diastolic (D), and atrial reversal (AR) phases of pulmonary venous flow were determined using the simplified Bernoulli equation and correlated with measured actual pressure differences. A linear relationship was observed between the convective (y) and actual (x) pressure differences for the S (y = 0.23x + 0.0074, r = 0.82) and D (y = 0.22x + 0.092, r = 0.81) waves, but not for the AR wave (y = 0. 030x + 0.13, r = 0.10). Numerical modeling resulted in similar slopes for the S (y = 0.200x - 0.127, r = 0.97), D (y = 0.247x - 0. 354, r = 0.99), and AR (y = 0.087x - 0.083, r = 0.96) waves. Consistent with numerical modeling, the convective term strongly correlates with but significantly underestimates actual gradient because of large inertial forces.

  4. Right Ventricular Doppler Echocardiographic Study of Indeterminate Form of Chagas Disease

    Directory of Open Access Journals (Sweden)

    Rogério Gomes Furtado

    2015-03-01

    Full Text Available Background: Patients with indeterminate form of Chagas disease/cardiac normality (ICD/CN exhibited normal electrocardiograms and chest X-rays; however, more sophisticated tests detected some degree of morphological and functional changes in the heart. Objective: To assess the prevalence of systolic and diastolic dysfunction of the right ventricle (RV in patients with ICD/CN. Methods: This was a case–control and prevalence study. Using Doppler two-dimensional echocardiography (2D, 92 patients were assessed and divided into two groups: group I (normal, n = 31 and group II (ICD/CN, n = 61. Results: The prevalence of RV systolic dysfunction in patients in groups I and II was as follows: fractional area change (0.0% versus 0.6%, mobility of the tricuspid annulus (0.0% versus 0.0%, and S-wave tissue Doppler (6.4% versus 26.0%, p = 0.016. The prevalence of global disorders such as the right myocardial performance index using tissue Doppler (16.1% versus 27.8%, p = 0.099 and pulsed Doppler (61.3% versus 68%, p = 0.141 and diastolic disorders such as abnormal relaxation (0.0% versus 6.0%, pseudonormal pattern (0.0% versus 0.0%, and restrictive pattern (0.0% versus 0.0% was not statistically different between groups. Conclusion: The prevalence of RV systolic dysfunction was estimated to be 26% (S wave velocity compared with other variables, suggesting incipient changes in RV systolic function in the ICD/CN group.

  5. 镜像右位心及合并畸形彩色多普勒超声心动图特征和规律性研究%Atudy on Imaging Characteristics and Regularity of Color Doppler Echocardiography on Mirror Image Dextrocardia and Deformity

    Institute of Scientific and Technical Information of China (English)

    侯传举; 齐岩梅; 邓东安; 朱鲜阳; 韩秀敏; 卢迪

    2011-01-01

    Objective To explore the image characteristics and regularity of color Doppler echocardiography (CDE)on mirror image dextrocardia and deformity. Methods One hundred patients with mirror image dextrocardia and deformity were examined by CDE and the image characteristics and regularity of CDE were found. Ninety-five cases with mirror image dextrocardia and deformity underwent angiocardiography examination after CDE, Seventy-six cases were proved by surgical operations. Results Ninety-two cases were diagnosed correctly by the features of CDE imaging. The diagnostic rate of accuracy is 92 %,eight cases were misdiagnosed. The features in the mirrorimage dextrocardia and deformity CDE image characteristics and regularity were obvious. ① Mirror image dextrocardia usually combines twelve kinds congenital heart disease,among them, ILL type double outlet right ventricle(27 % )are common. IDD type corrected transposition of the great arteies( 17 % ),tetralogy of Fallot(16 % )and ventrcluar septal defect( 12 % )are not as common as the above. Double-inlet ventricle( 7 % ), tricuspid atresia( 5 % ), bilocular heart( 5 % ), ILL type complete transposition of the great arteies(4% ), mitral atresia(2 % ), isolated right ventricular outlet stenosis(2 % ), total anomalous pulmonary venous drainage( 2 % ), and isolated cleft mitral valve ( 1% ) are rare. ② Despite the diversity of combined congenital heart disease,all cases of adult mirror image dextrocardia have a common CDE characteristic of atria situs inversus. ③ adult mirror image dextrocardia combined double outlet right ventricle and complete transposition of the great arteies are left-transposition,combined corrected transposition of the great arteies are right-transposition.④ Mirror image dextrocardia combined pulmonary stenosis(80 % ) are common, pulmonary normal( 12 % ) and pulmonary hypertension(8%)are rare. ⑤ atral septal defect and ventricular septal defect color Doppler flow

  6. The Value of Contrast Echocardiography

    Directory of Open Access Journals (Sweden)

    Shannon C. Treiber

    2016-01-01

    Full Text Available Purpose: There is much evidence-based research proving the effectiveness of contrast echocardiography, but there are still questions and concerns about its specific uses. This study tested the effectiveness of contrast echocardiography in defining the left ventricular endocardial border. Methods: From 30 patients, a total of 60 echocardiograms –– 30 with and 30 without use of contrast –– were retrospectively reviewed by four blinded cardiologists with advanced training in echocardiography. No single cardiologist reviewed contrast and noncontrast images of the same patient. Each set of 30 echocardiograms was then studied for wall-motion scoring. Visualization of left ventricular wall segments and a global visualization confidence level of interpretation were recorded. Results: Of all wall segments (N = 510, 91% were visualized in echocardiograms with use of contrast, whereas 75% of the walls were visualized in echocardiograms without contrast (P < 0.001. Of 30 examinations, 17 contrast echocardiograms were read with high confidence compared to 6 without contrast use (P = 0.004. The number of walls visualized with contrast was increased in 18 patients (60%, whereas noncontrast echocardiograms yielded more visualized walls in 6 patients (20%, P = 0.002. Conclusions: This study demonstrates that contrast is valuable to echocardiographic imaging. Its use should be supported throughout echocardiography clinics and encouraged in certain patients for whom resting and stress echocardiography results without contrast often prove uninterpretable.

  7. Velocity-aligned Doppler spectroscopy

    Science.gov (United States)

    Xu, Z.; Koplitz, B.; Wittig, C.

    1989-03-01

    The use of velocity-aligned Doppler spectroscopy (VADS) to measure center-of-mass kinetic-energy distributions of nascent photofragments produced in pulsed-initiation photolysis/probe experiments is described and demonstrated. In VADS, pulsed photolysis and probe laser beams counterpropagate through the ionization region of a time-of-flight mass spectrometer. The theoretical principles of VADS and the mathematical interpretation of VADS data are explained and illustrated with diagrams; the experimental setup is described; and results for the photodissociation of HI, H2S, and NH3 are presented in graphs and characterized in detail. VADS is shown to give much higher kinetic-energy resolution than conventional Doppler spectroscopy.

  8. The doppler ultrasound. La ecografia Doppler

    Energy Technology Data Exchange (ETDEWEB)

    Contreras Cecilia, E.; Lozano Setien, E.; Hernandez Montero, J.; Ganado Diaz, T.; Jorquera Moya, M.; Blasco Pascual, E. (Hospital Universitario San Carlos. Madrid (Spain))

    1994-01-01

    The discovery and development of Doppler ultrasound has had a great influence on Medical practice since it allows the noninvasive study of vascular pathology, both arterial and venous, as well as the flow patterns of the different parenchyma. This article deals with the principles, limitations and interpretation of the Doppler signal, as well as the different Doppler ultrasound systems routinely employed in Medicine.

  9. Echocardiography in chronic liver disease: systematic review.

    Science.gov (United States)

    Mota, Vitor Gomes; Markman Filho, Brivaldo

    2013-04-01

    Doppler echocardiography (Echo) is a non-invasive method of excellent accuracy to screen portopulmonary hypertension (PPH) and to assess intrapulmonary shunts (IPS) in chronic liver disease (CLD). In the past decade, Echo proved to play a fundamental role in the diagnosis of cirrhotic cardiomyopathy (CCM). To perform a systematic review of relevant articles on the subject 'Echo in CLD'. In November 2011, a systematic review was performed in the PubMed, LILACS and SciELO databases, and the characteristics of the studies selected were reported. The search based on descriptors and free terms obtained 204 articles (179 in Pubmed, 21 in LILACS, and 1 in SciELO). Of those 204 articles, 22 were selected for systematic review. A meta-analysis could not be performed because of the heterogeneity of the articles. Echo should be part of CLD stratification for screening PPH, IPS and CCM, because, most of the time, such complications are diagnosed only when patients are already waiting for a liver transplant.

  10. Contrast biases the autocorrelation phase shift estimation in Doppler tissue imaging.

    Science.gov (United States)

    Ressner, Marcus; Jansson, Tomas; Cedefamn, Jonny; Ask, Per; Janerot-Sjoberg, Birgitta

    2009-03-01

    Quantitative assessment of regional myocardial function at rest and during stress with Doppler tissue imaging (DTI) plays an important role in daily routine echocardiography. However, reliable visual analysis is largely dependent on image quality and adequate border delineation, which still remains a challenge in a significant number of patients. In this respect, an ultrasound contrast agent (UCA) is often used to improve visualization in patients with suboptimal image quality. The knowledge of how DTI measurements will be affected by UCA present in the tissue is therefore of significant importance for an accurate interpretation of local myocardial motion. The aim of this paper was to investigate how signal contribution from UCA and nonlinear wave propagation influence the performance of the autocorrelation phase shift estimator used for DTI applications. Our results are based on model experiments with a clinical 2-D grayscale scanner and computational simulations of the DTI velocity estimator for synthetically-derived pulses, simulated bubble echoes and experimentally-sampled RF data of transmitted pulses and backscattered contrast echoes. The results show that destruction of UCA present in the tissue will give rise to an apparent bidirectional velocity bias of individual velocity estimates, but that spatial averaging of individual velocity measurements within a region-of-interest will result in a negative bias (away from the transducer) of the estimated mean or mean peak velocity. The UCA destruction will also have a significant impact on the measured integrated mean velocity over time, i.e., displacement. To achieve improved visualization with UCA during DTI-examinations, we either recommend that it is performed at low acoustic powers, mechanical index Doppler pulse package is preceded by a destruction burst similar to "Flash imaging" to clear the target area of contrast microbubbles.

  11. Development of heart failure assessed by tissue Doppler imaging in hypertensive Dahl rats

    OpenAIRE

    宮田, 聖子||ミヤタ, セイコ||Miyata, Seiko; 山田, 亜紀||ヤマダ, アキ||Yamada, Aki||Iwami Yamada, Aki; 橋本, 克徳||ハシモト, カツノリ||Hashimoto, Katsunori; 黒木, 祥子||クロキ, ショウコ||Kuroki, Shoko; 岩本, 隆司||イワモト, タカシ||Iwamoto, Takashi; 野田, 明子||ノダ, アキコ||Noda, Akiko

    2014-01-01

    Objective: Tissue Doppler imaging (TDI) has been recognized as a useful tool to assess regional myocardial function. The purpose of this study was to evaluate the development of heart failure in hypertensive Dahl rats using echocardiography with TDI. Methods: Dahl salt-sensitive (DS) rats were placed on 8% NaCl diet from 7 weeks old. As an age-matched control, DS rats were consistently placed on normal diet. In these rats, echocardiography was performed successively. We evaluated interventric...

  12. European association of echocardiography recommendations for the assessment of valvular regurgitation. Part 2: Mitral and tricuspid regurgitation (native valve disease)

    NARCIS (Netherlands)

    P. Lancellotti (Patrizio); L. Moura (Luis); L. Pié rard (Luc); E. Agricola (Eustachio); B.A. Popescu (Bogdan); C. Tribouilloy (Christophe); A. Hagendorff (Andreas); J.L. Monin; L. Badano (Luigi); J.L. Zamorano (Jose); R. Sicari (Rosa); A. Vahanian (Alec); J.R.T.C. Roelandt (Jos)

    2010-01-01

    textabstractMitral and tricuspid are increasingly prevalent. Doppler echocardiography not only detects the presence of regurgitation but also permits to understand mechanisms of regurgitation, quantification of its severity and repercussions. The present document aims to provide standards for the as

  13. European association of echocardiography recommendations for the assessment of valvular regurgitation. Part 2: Mitral and tricuspid regurgitation (native valve disease)

    NARCIS (Netherlands)

    P. Lancellotti (Patrizio); L. Moura (Luis); L. Pié rard (Luc); E. Agricola (Eustachio); B.A. Popescu (Bogdan); C. Tribouilloy (Christophe); A. Hagendorff (Andreas); J.L. Monin; L. Badano (Luigi); J.L. Zamorano (Jose); R. Sicari (Rosa); A. Vahanian (Alec); J.R.T.C. Roelandt (Jos)

    2010-01-01

    textabstractMitral and tricuspid are increasingly prevalent. Doppler echocardiography not only detects the presence of regurgitation but also permits to understand mechanisms of regurgitation, quantification of its severity and repercussions. The present document aims to provide standards for the as

  14. Feasibility of exercise stress echocardiography and myocardial response in patients with repaired congenital heart disease.

    Science.gov (United States)

    Hasan, Babar S; Lunze, Fatima I; Alvi, Najveen; Shafer, Keri M; Rhodes, Jonathan

    2017-06-01

    Exercise stress echocardiography (ESE) can unmask ventricular dysfunction in asymptomatic patients with congenital heart disease (CHD), but its acquisition and interpretation is often challenging, and the method has not been validated in CHD. This study aimed to evaluate the feasibility of ESE using Doppler imaging and to assess myocardial response to exercise in patients with biventricular (BiV) and univentricular (UniV) circulation after CHD repair. In this single-center prospective study, we recruited 55 participants (17 females), median age 14 years (8-22 years). Our analysis categorized participants in these three groups: with structurally normal hearts as controls (n=21), with BiV circulation (n=20) and with UniV circulation (n=14). We acquired ESE images of the systemic ventricle including pulsed-wave flow and spectral tissue Doppler imaging (TDI) of lateral free wall before and immediately after standard, symptom-limited exercise tests on an electronically braked cycle ergometer. During ESE we obtained inflow E-wave and TDI systolic (S') and early diastolic (E') velocities in 93% to 100% of participants at rest and in 90% to 100% of participants post exercise. Feasibility to obtain Doppler imaging parameter was the same across study groups. The myocardial response to exercise was increase in heart rate (HR), S' and inflow E-wave velocity in all participants. Patients with BiV circulation had preserved ventricular function at rest. While patients with UniV circulation had low S', E', and E-wave velocities at rest in comparison to controls and to BiV group (all Pincreases in HR, S' velocity and inflow E-wave velocity post exercise, with magnitudes of these increases higher in controls than in the BiV and UniV group. The S' and E' velocities were strongly associated with lower percent predicted peak oxygen consumption VO2 (rs=0.614 and rs=0.64, respectively, both Pexercise in patients after biventricular and univentricular CHD repair. Although patients with Bi

  15. Meta-analysis on the association between subclinical hypothyroidism and the left ventricular functions under Doppler echocardiography%多普勒超声心动图评价亚临床甲状腺功能减退与左心室功能关系的Meta分析

    Institute of Scientific and Technical Information of China (English)

    陈欣; 张娜; 张文良; 时景璞

    2011-01-01

    目的 应用传统二维多普勒超声心动图定量评价亚临床甲状腺功能减退(亚甲减)与左心室功能的关系.方法 检索国内外数据库1999-2011年5月发表的有关亚甲减与左心室功能关系的文献,用左心室射血分数(LVEF)和左心室短轴缩短率(FS)评价左心室收缩功能;以左心室舒张早期血流充盈速度(E)和舒张晚期血流充盈速度(A)及其比值(E/A)、左心室等容舒张时间(IVRT)评价左心室舒张功能.采用Meta分析方法,利用Stata 11软件评价亚甲减与左心室收缩和舒张功能的关系.计算各指标的加权均数差(WMD)及其95%CI,并用Begg's检验法评价发表性偏倚.结果 共纳入13篇文献.(1)数据合并结果显示,在评价左心室舒张功能的指标中,亚甲减病例组与对照组的A(WMD=4.51,95%CI:2.41 ~ 6.61)、E/A(WMD =~0.22,95%CI:-0.30 ~-0.13)和IVRT(WMD=6.13,95%CI:2.79~9.48)差异均有统计学意义(P<0.05),E的差异无统计学意义(P>0.05);在评价左心室收缩功能的指标中,亚甲减病例组与对照组的LVEF、FS差异均无统计学意义(P>0.05).(2)亚组分析显示,在平均心率(HR)≥72 bpm组,亚甲减病例组和对照组的A、E/A和IVRT差异有统计学意义(P<0.05);在<72 bpm组,IVRT差异有统计学意义(P<0.05);在平均年龄<60岁组,亚甲减病例组和对照组的A差异有统计学意义(P<0.05).结论 亚甲减与左心室舒张功能减退有明显相关性,但与左心室收缩功能减退无明显相关性,提示亚甲减可导致心脏功能的改变,可通过多普勒超声心动图给予评价.%Objective To explore the association between subclinical hypothyroidism and the left ventricular functions under conventional 2D Doppler echocardiography and to provide evidence for the protection of heart function.Methods Literatures regarding the association of subclinical hypothyroidism and the left ventricular functions were retrieved in large databases from

  16. 多普勒组织成像结合心肌声学造影评估无复流时心脏收缩和舒张功能的变化%Evaluation of cardiac contractility and relaxation during no-reflow phenomenon by the combination of Doppler tissue imaging with myocardial contrast echocardiography

    Institute of Scientific and Technical Information of China (English)

    焦阳; 陈立新; 陶红; 朱向明

    2008-01-01

    AIM: To evaluate the cardiac contractility and relaxation by Doppler tissue imaging (DTI) combined with myocardial contrast echocardiography (MCE) via injection of contrast media, Albunex. METHODS: Nineteen healthy mongrel dogs were conducted 60 min ligation of left anterior descending coronary artery (LAD), followed by reperfusion of 60, 120 and 180 min to establish an acute myocardial ischemic-reperfused canine model. (1) MCE was performed by bolus injection of Albunex at pre-reperfusion and at post-reperfusion. The perfused defect area defined by MCE at pre-reperfusion was regarded as risk area (RAMCE), while perfused defect area at post-reperfusion was regarded as no-reflow area (NRAMCE). When the ratio of NRAMCE to RAMCE exceeded 25%, myocardial reperfusion was considered incomplete, I.e., no-reflow group; If the ratio was <25%, myocardial reperfusion was considered adequate, I.e., reflow group. (2) Left ventricular ejection fraction (LVEF) and wall thickness ratio (△T%) of LV anterior wall were determined. (3)S-wave, e-wave and a-wave velocities at the LV anterior wall were determined by DTI. The e/a ratio was measured. RESULTS: The results of MCE showed 7 dogs in reflow group and 10 dogs in no-reflow group. (1) LVEF in reflow group gradually increased with time course after myocardial reperfusion, and in no-reflow group, however, LVEF increasingly declined with ongoing myocardial reperfusion. At the same reperfusion time point, LVEF of no-reflow group was significantly lower than that of reflow group. (2) △T% in reflow group improved gradually, and however, it can not come back to that of baseline at 180-min reperfusion. △T% in no-reflow group had no signal of recovery with progressive reperfusion. (3) S-wave, e-wave velocities measured by DTI significantly declined after ligation of LAD, and a-wave velocity increased, leading to decline of e/a. After myocardial reperfusion, s-wave, e-wave velocities and e/a in reflow group gradually increased at

  17. Usefulness of echocardiography in preparticipation screening of competitive athletes.

    Science.gov (United States)

    Grazioli, Gonzalo; Merino, Beatriz; Montserrat, Silvia; Vidal, Bàrbara; Azqueta, Manel; Pare, Carles; Sarquella-Brugada, Georgia; Yangüas, Xavier; Pi, Ramon; Til, Lluis; Escoda, Jaume; Brugada, Josep; Sitges, Marta

    2014-09-01

    Despite the established diagnostic value of the electrocardiogram in preparticipation screening of athletes, some cardiac structural changes can be missed, particularly in early disease stages. The aim of this study was to evaluate the prevalence of cardiac structural changes via the systematic use of echocardiography in preparticipation screening of competitive athletes. Professional athletes or participants in a competitive athletic program underwent a screening that included family and personal medical history, physical examination, electrocardiography, exercise testing, and Doppler echocardiography. A total of 2688 athletes (67% men; mean age [standard deviation], 21 [10] years) were included. Most of the echocardiographic evaluations (92.5%) were normal and only 203 (7.5%) showed changes; the most frequent change was left ventricular hypertrophy, seen in 50 athletes (1.8%). Cessation of athletic activity was indicated in 4 athletes (0.14%): 2 for hypertrophic cardiomyopathy (electrocardiography had shown changes that did not meet diagnostic criteria), 1 pectus excavatum with compression of the right ventricle, and 1 significant pulmonary valve stenosis; the rest of the changes did not entail cessation of athletic activity and only indicated periodic monitoring. Although rare, some cardiac structural changes can be missed on physical examination and electrocardiography; in contrast, they are easily recognized with echocardiography. These findings suggest the use of echocardiography in at least the first preparticipation screening of competitive athletes to improve the effectiveness of programs aimed at preventing sudden death in athletes. Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

  18. The potential role and limitations of echocardiography in acute respiratory distress syndrome.

    Science.gov (United States)

    Lazzeri, Chiara; Cianchi, Giovanni; Bonizzoli, Manuela; Batacchi, Stefano; Peris, Adriano; Gensini, Gian Franco

    2016-04-01

    Bedside use of Doppler echocardiography is being featured as a promising, clinically useful tool in assessing the pulmonary circulation in patients with acute respiratory distress syndrome (ARDS). The present review is aimed at summarizing the available evidence obtained with echocardiography on right ventricle (RV) function and pulmonary circulation in ARDS and to highlight the potential of this technique in clinical practice (only articles in English language were considered). According to the available evidence on echocardiographic findings, the following conclusions can be drawn: (a) echocardiography (transthoracic and transesophageal) has a growing role in the management ARDS patients mainly because of the strict interactions between the lung (and ventilation) and the RV and pulmonary circulation; (b) there may be a continuum of alterations in RV size and function and pulmonary circulation which may end in the development of acute cor pulmonale, probably paralleling ARDS disease severity; and (c) the detection of acute cor pulmonale should prompt intensivists to tailor their ventilatory strategy to the individual patient depending on the echocardiography findings. Bearing in mind the clinical role and growing importance of echocardiography in ARDS and the available evidence on this topic, we present a flow chart including the parameters to be measured and the timing of echo exams in ARDS patients. Despite the important progress that echocardiography has gained in the evaluation of patients with ARDS, several open questions remain and echocardiography still appears to be underused in these patients. A more systematic use of echocardiography (mainly through shared protocols) in ARDS could help intensivists to tailor the optimal treatment in individual patients as well as highlighting the limits and potential of this methodology in patients with ALI.

  19. Evaluación de la función diastólica en la enfermedad de chagas mediante doppler tisular pulsado

    Directory of Open Access Journals (Sweden)

    R. A. Migliore

    2003-12-01

    Full Text Available En la etapa indeterminada de la enfermedad de Chagas las alteraciones de la función diastólica preceden a las de la función sistólica. El Doppler tisular pulsado es una nueva técnica no invasiva que permite analizar la función diastólica mediante el registro de la velocidad de estiramiento miocárdico en el eje longitudinal. Con el objetivo de evaluar la función diastólica en la enfermedad de Chagas mediante Doppler tisular pulsado fueron estudiados con ecocardiograma y Doppler 51 pacientes con serología positiva para enfermedad de Chagas (48 ± 12 años y 24 individuos normales (47 ± 15 años como grupo control. De acuerdo al patrón del flujo mitral y de vena pulmonar los pacientes con enfermedad de Chagas fueron divididos en 2 grupos: restrictivo (17 pacientes y no restrictivo (34 pacientes. La velocidad pico de la onda E del anillo lateral mitral estuvo disminuida en los pacientes con patrón no restrictivo y restrictivo (0.13 ± 0.04 m/seg, 0.11 ± 0.05 m/seg respectivamente con respecto al grupo control (0.18 ± 0.07 m/seg, pDiastolic function is early involved during the undetermined form of Chagas disease. Pulsed Doppler tissue imaging is a new technique to evaluate diastolic function by mean of the record of myocardial velocities in the longitudinal axis. With the purpose to evaluate diastolic function by pulsed Doppler tissue imaging in patients with Chagas disease, we studied with Doppler echocardiography 51 patients (age average 48 ± 12 years and 24 normal subjects (age average 47 ± 15 years as a control group. Patients were divided in two groups according to the pattern of mitral and pulmonary vein flow: restrictive (17 patients and no restrictive (35 patients. Peak velocity of E wave of the lateral mitral annulus was diminished in no restrictive and restrictive patients (0.13 ± 0.04 m/s, 0.11 ± 0.05 m/s respectively in regard to control group (0.18 ± 0.07 m/s, p<0.01. Pulsed Doppler tissue imaging was useful in the

  20. Acute hemodynamic effect of inhaled iloprost in pulmonary artery hypertension evaluated with echocardiography

    Directory of Open Access Journals (Sweden)

    Miranda Rita

    2007-11-01

    Full Text Available Abstract Doppler echocardiography is useful in the initial evaluation and long-term follow-up of patients with pulmonary artery hypertension. Aerosolised iloprost has been shown to reduce pulmonary pressure immediately after inhalation. We report the echocardiographic findings in a patient with severe pulmonary hypertension, before and after the inhalation of aerosolized iloprost. These findings illustrate the acute influence of iloprost in right and left ventricular hemodynamics and morphology. These findings were reproduced in subsequent echocardiographic evaluations.

  1. 经颅多普勒增强实验结合经食管超声鉴别肺动静脉瘘与卵圆孔未闭所致隐源性卒中的研究%The Significance of Contrast Transcranial Doppler Combined with Transesophageal Echocardiography in the Differential Diagnosis of Cryptogenic Stroke with Pulmonary Arteriovenous Fistula and Patent Foramen Ovale

    Institute of Scientific and Technical Information of China (English)

    董培; 潘华

    2016-01-01

    目的:探讨经颅多普勒增强实验(contrast transcranial Doppler,cTCD)结合经食管超声(transesophageal echocardiography,TEE)对于鉴别肺动静脉瘘(pulmonary arteriovenous fistula,PAVF)与卵圆孔未闭(patent foramen ovale,PFO)所致隐源性卒中的意义。方法收集4例隐源性卒中患者(PAVF组2例,PFO组2例)的临床资料,行cTCD、TEE检查,比较两组的检查结果差异。结果 PAVF组cTCD结果显示患者平静呼吸时即见雨帘样栓子信号,Valsalva动作(Valsalva maneuver, VM)后栓子数量变化不明显;TEE彩色多普勒(color Doppler flow image,CDFI)未见异常,右心声学造影VM后5个心动周期左房内肺静脉开口处见大量微泡。PFO组cTCD结果显示,一例平静呼吸时可见4个栓子,VM后雨帘样栓子信号,VM作用消失后第40个心动周期有2个栓子信号。一例平静呼吸时无栓子信号,VM后可见>50个栓子信号,VM作用消失后无栓子信号。TEECDFI示原发隔继发隔间裂隙左向右过隔血流,右心声学造影VM后2~3个心动周期卵圆孔附近的左心房内见数个微气泡。结论 cTCD结合TEE鉴别诊断PFO和PAVF敏感性高,易于操作。二者主要鉴别点在于cTCD平静呼吸时是否出现大量栓子及是否受VM影响。%Objective To explore the significance of contrast transcranial Doppler (cTCD) combined with transesophageal echocardiography (TEE) in the differential diagnosis of cryptogenic stroke with pulmonary arteriovenous ifstula and patent foramen ovale. Methods Detailed clinical information were collected. TEE and cTCD were performed in 4 patients with cryptogenic stroke (2 patients with pulmonary arteriovenous fistula [PAVF] and 2 patients with patent foramen ovale [PFO]) to compare the difference in test results. Results cTCD in 2 patients with PAVF showed the following characteristics: detection of massive microembolic signals (curtain pattern) during regular

  2. Ekhokardiografi Endokardiosis Penyakit Katup Mitral Jantung Anjing (ECHOCARDIOGRAPHY OF ENDOCARDIOSIS MITRAL VALVE HEART DISEASE IN DOGS

    Directory of Open Access Journals (Sweden)

    Deni Noviana

    2013-08-01

    Full Text Available Endocardiosis is a disease commonly found in Pomeranian dog characterized by progressive myxomatousdegeneration of the atrio-ventricular valves especially in the mitral valve. The purpose of this study was todefine the diagnose and severeity of this disease on the Pomeranian by using brightness mode, motion mode,dan color flow Doppler echocardiography technique. Echocardiography was performed on 8 Pomeranianconsisting of 6 males and 2 females with age range of 2-14 years. Brightness mode echocardiography wasused to see the echotexture of endocardium, mitral valve, and the valve movement. The results showedendocardium thickening, along with chronic fibrosis and nodular thickening of the anterior and posteriormitral valve leaflet. Three out of seven cases showed prolapsed of the mitral valve. Motion modeechocardiography was performed in order to measure left ventricle internal dimension, myocardium thickness,fractional shortening, left atrial and aortic dimension. The results showed myocardium thickening, alongwith left atrial enlargement. Color flow Doppler echocardiography was used to confirm the mitral valveregurgitation. Three of seven cases showed the presence of regurgitation signed by turbulence color of theprolapsed mitral valve. Based on the degree of severity, scoring system used in this study, endocardiosis canbe divided into three types that are mild, moderate and severe.

  3. Compressive sensing for high resolution profiles with enhanced Doppler performance

    NARCIS (Netherlands)

    Anitori, L.; Hoogeboom, P.; Chevalier, F. Le; Otten, M.P.G.

    2012-01-01

    In this paper we demonstrate how Compressive Sensing (CS) can be used in pulse-Doppler radars to improve the Doppler performance while preserving range resolution. We investigate here two types of stepped frequency waveforms, the coherent frequency bursts and successive frequency ramps, which can be

  4. Right ventricular involvement in patients with inferior myocardial infarction, correlation of electrocardiographic findings with echocardiography data.

    Science.gov (United States)

    Javed, Sumbul; Rajani, Ali Raza; Govindaswamy, Pushparani; Radaideh, Ghazi Ahmed; Abubaraka, Harb Ahmed; Qureshi, Tariq Ilyas; Arshad, Hassaan Bin

    2017-03-01

    To determine the right ventricular involvement in patients with inferior myocardial infarction by echocardiography in relation to electrocardiographic findings. This observational, prospective study was conducted at Rashid Hospital, Dubai, the United Arab Emirates, from January to September 2013, and comprised patients with inferior myocardial infarction. All patients aged above 18 years were included. Right ventricular myocardial infarction was defined by the electrocardiographic criteria of > 1mV ST elevation in V4R-V5R leads. RV infarction was assessed on echocardiography by fractional area change, tricuspid annular plane systolic excursion and tricuspid annular systolic velocity by tissue Doppler imaging. SPSS 21 was used for data analysis. Of the 73 patients, there were 68(93%) men and 5(7%) women. The three modalities used to assess the right ventricular infarction showed right ventricular involvement in 36(49.3%) cases by fractional area change, 28(38.4%) cases by tricuspid annular plane systolic excursion and 31(42.5%) cases by tissue Doppler imaging in patients with inferior myocardial infarction. Tissue Doppler imaging and right ventricular function showed low degree of negative correlation (p=0.16) while the correlation between tricuspid annular plane systolic excursion and right ventricular function showed significant positive correlation (pright ventricular infarction by echocardiography helped to diagnose right ventricular infarction in greater number of cases compared to surface electrocardiogram.

  5. Coronary Flow Velocity Reserve Assessed by Transthoracic Doppler

    DEFF Research Database (Denmark)

    Michelsen, Marie M; Peña, Adam; Mygind, Naja D

    2016-01-01

    the feasibility and factors associated with the quality of CFVR obtained in a large prospective study of women suspected of having microvascular disease. METHODS: Women with angina-like chest pain and no obstructive coronary artery disease on coronary angiography (stenosis) were consecutively examined......BACKGROUND: Coronary flow velocity reserve (CFVR) measured by transthoracic Doppler echocardiography is a noninvasive measure of microvascular function, but it has not achieved widespread use, mainly because of concerns of validity and feasibility. The aim of this study was to describe...... by transthoracic Doppler echocardiography of the left anterior descending coronary artery to measure CFVR (n = 947). Quality was evaluated on the basis of (1) identification of the left anterior descending coronary artery, (2) maintained probe position throughout the examination, (3) visibility and configuration...

  6. Left ventricular function in professional football players evaluated by tissue Doppler imaging and strain imaging.

    Science.gov (United States)

    Tümüklü, Mustafa Murat; Etikan, Ilker; Cinar, Cahide Soydaş

    2008-01-01

    Long-term regular exercise is associated with physiologic and morphologic cardiac alterations. Tissue Doppler Imaging(TDI) and Strain Myocardial Imaging(SI) are new tools in the evaluation systolic and diastolic myocardial function. We sought to compare TDI and SI findings in professional football players and age adjusted sedentary controls to assess the effect of regular athletic training on myocardial function. Transthoracic echocardiography, M-mode, 2-D measurements, Doppler derived mitral-tricuspid annular velocities, reconstructed spectral pulsed wave tissue Doppler velocities, strain and strain rate imaging of seven different myocardial regions were obtained from 24 professional football players and age, sex and weight adjusted 20 controls. Age, body surface area, blood pressure and heart rate were comparable between 2 groups. Football players had significantly increased LV mass, mass index (due to both higher wall thickness and end-diastolic diameter), end-systolic and end-diastolic volume, left atrial diameter and decreased transmitral diastolic late velocity. In athletes TDI analysis showed significantly increased mitral annulus septal TDI peak early diastolic(e) velocity(0.22 +/- 0.04 vs. 0.19 +/- 0.04 m/s, P velocity (0.19 +/- 0.03 vs. 0.16 +/- 0.02 m/s, P football playing is associated with morphologic alteration in left ventricle and left atrium and improvement in left ventricle diastolic function which can be detected by TDI. Strain rate imaging may be a new tool to define subtle change in systolic left ventricular function in "athletes heart" which cannot be determined in standard echocardiographic parameters.

  7. Isometric exercise in the denervated heart: a Doppler echocardiographic study.

    OpenAIRE

    Robson, S C; Furniss, S.S.; Heads, A; Boys, R J; McGregor, C.; Bexton, R S

    1989-01-01

    The haemodynamic responses to isometric exercise of eight recipients of orthotopic heart transplants and eight healthy controls were studied. Each performed sustained exercise at 30% of maximal voluntary contraction for three minutes on a handgrip dynamometer. Cardiac output was measured by combined Doppler and cross sectional echocardiography before exercise and every 30 seconds during and after exercise. In the controls cardiac output and blood pressure increased significantly owing to an i...

  8. Using doppler radar images to estimate aircraft navigational heading error

    Science.gov (United States)

    Doerry, Armin W [Albuquerque, NM; Jordan, Jay D [Albuquerque, NM; Kim, Theodore J [Albuquerque, NM

    2012-07-03

    A yaw angle error of a motion measurement system carried on an aircraft for navigation is estimated from Doppler radar images captured using the aircraft. At least two radar pulses aimed at respectively different physical locations in a targeted area are transmitted from a radar antenna carried on the aircraft. At least two Doppler radar images that respectively correspond to the at least two transmitted radar pulses are produced. These images are used to produce an estimate of the yaw angle error.

  9. Transesophageal color Doppler evaluation of obstructive lesions using the new "Quasar" technology.

    Science.gov (United States)

    Fan, P; Nanda, N C; Gatewood, R P; Cape, E G; Yoganathan, A P

    1995-01-01

    Due to the unavoidable problem of aliasing, color flow signals from high blood flow velocities cannot be measured directly by conventional color Doppler. A new technology termed Quantitative Un-Aliased Speed Algorithm Recognition (Quasar) has been developed to overcome this limitation. Employing this technology, we used transesophageal color Doppler echocardiography to investigate whether the velocities detected by the Quasar would correlate with those obtained by continuous-wave Doppler both in vitro and in vivo. In the in vitro study, a 5.0 MHz transesophageal transducer of a Kontron Sigma 44 color Doppler flow system was used. Fourteen different peak velocities calculated and recorded by color Doppler-guided continuous-wave Doppler were randomly selected. In the clinical study, intraoperative transesophageal echocardiography was performed using the same transducer 18 adults (13 aortic valve stenosis, 2 aortic and 2 mitral stenosis, 2 hypertrophic obstructive cardiomyopathy and 1 mitral valve stenosis). Following each continuous-wave Doppler measurement, the Quasar was activated, and a small Quasar marker was placed in the brightest area of the color flow jet to obtain the maximum mean velocity readout. The maximum mean velocities measured by Quasar closely correlated with maximum peak velocities obtained by color flow guided continuous-wave Doppler in both in vitro (0.53 to 1.65 m/s, r = 0.99) and in vivo studies (1.50 to 6.01 m/s, r = 0.97). We conclude that the new Quasar technology can accurately measure high blood flow velocities during transesophageal color Doppler echocardiography. This technique has the potential of obviating the need for continuous-wave Doppler.

  10. Effect of DRFM phase responsext on the doppler spectrum of a coherent radar: critical implications and possible mitigation techniques

    CSIR Research Space (South Africa)

    Herselman, PL

    2006-02-01

    Full Text Available In this research, the critical implications of the phase response of a Digital Radio Frequency Memory (DRFM) based repeater system on the Doppler spectrum of a modern, coherently processing radar system (for example pulsed Doppler radar...

  11. Maternal psychological impact of fetal echocardiography.

    Science.gov (United States)

    Sklansky, Mark; Tang, Alvin; Levy, Denis; Grossfeld, Paul; Kashani, Iraj; Shaughnessy, Robin; Rothman, Abraham

    2002-02-01

    The maternal psychological impact of fetal echocardiography may be deleterious in the face of newly diagnosed congenital heart disease. This questionnaire-based study prospectively examined the psychological impact of both normal and abnormal fetal echocardiography. Normal fetal echocardiography decreased maternal anxiety, increased happiness, and increased the closeness women felt toward their unborn children. In contrast, when fetal echocardiography detected congenital heart disease, maternal anxiety typically increased, and mothers commonly felt less happy about being pregnant. However, among women who had recently delivered infants with congenital heart disease, those who had had fetal echocardiography during the pregnancy felt less responsible for their infants' defects and tended to have improved their relationships with the infants' fathers after the prenatal diagnosis of congenital heart disease. Further study of the psychological and medical impact of fetal echocardiography will be necessary to define and optimize the clinical value of this powerful diagnostic tool.

  12. Goal-Directed Fluid Therapy Guided by Cardiac Monitoring During High-Risk Abdominal Surgery in Adult Patients: Cost-Effectiveness Analysis of Esophageal Doppler and Arterial Pulse Pressure Waveform Analysis.

    Science.gov (United States)

    Legrand, Guillaume; Ruscio, Laura; Benhamou, Dan; Pelletier-Fleury, Nathalie

    2015-07-01

    Several minimally invasive techniques for cardiac output monitoring such as the esophageal Doppler (ED) and arterial pulse pressure waveform analysis (APPWA) have been shown to improve surgical outcomes compared with conventional clinical assessment (CCA). To evaluate the cost-effectiveness of these techniques in high-risk abdominal surgery from the perspective of the French public health insurance fund. An analytical decision model was constructed to compare the cost-effectiveness of ED, APPWA, and CCA. Effectiveness data were defined from meta-analyses of randomized clinical trials. The clinical end points were avoidance of hospital mortality and avoidance of major complications. Hospital costs were estimated by the cost of corresponding diagnosis-related groups. Both goal-directed therapy strategies evaluated were more effective and less costly than CCA. Perioperative mortality and the rate of major complications were reduced by the use of ED and APPWA. Cost reduction was mainly due to the decrease in the rate of major complications. APPWA was dominant compared with ED in 71.6% and 27.6% and dominated in 23.8% and 20.8% of the cases when the end point considered was "major complications avoided" and "death avoided," respectively. Regarding cost per death avoided, APPWA was more likely to be cost-effective than ED in a wide range of willingness to pay. Cardiac output monitoring during high-risk abdominal surgery is cost-effective and is associated with a reduced rate of hospital mortality and major complications, whatever the device used. The two devices evaluated had negligible costs compared with the observed reduction in hospital costs. Our comparative studies suggest a larger effect with APPWA that needs to be confirmed by further studies. Copyright © 2015 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  13. Doppler imaging of myocardium tissue from aged hypertensive patients with increased differential pulse pressure%老年脉压差增大高血压患者心肌多普勒成像改变

    Institute of Scientific and Technical Information of China (English)

    王新明; 孙红

    2012-01-01

    Objective To assess the effect of increased differential pulse pressure on myocardium function in aged patients by tissue Doppler imaging(TDI). Medthods One hundred and one aged patients were divided into normal pressure group with their differential pulse pressure ≤40 mm Hg(n = 45) and hypertension group with their differential pulse >40 mm Hg(n = 56). The inner diameter and interventricular septal thickness of ascending aorta,thickness of lefet ventricle posterior wall,inner diameter of left ventricle at late diastolic phase,maximum blood flow speed through mitral vlve at early diastolic phase were measured to detect the peak blood flow speed at diastolic phase,early diastolic phase and late diastolic phase. Results The peak blood flow speed at diastolic phase,early diastolic phase and late diastolic phase was higher in hypertension group than in normal pressure group. Conclusion TDI is a reliable new procedure for the diagnosis of abnormal systolic and diastolic function of myocardium due to increased differential pulse pressure in aged patients with hypertension. The mitral valve ring in left ventricular septum is sensitive to TDI in measuring systolic pressure.%目的 应用组织多普勒超声成像评价老年脉压差增大对心肌收缩和舒张功能的影响.方法 应用常规超声心动图及组织多普勒等方法检测左心室射血分数>50%的老年男性高血压患者共101例,其中血压正常、脉压差≤40 mm Hg(1 mm Hg=0.133 kPa)45例(正常组),高血压、且脉压差>40 mm Hg 56例(异常组),测量升主动脉内径、室间隔厚度、左心室后壁厚度、左心室舒张末内径、左心室舒张早期二尖瓣血流最大速度和左心室舒张晚期二尖瓣血流最大速度(A)值,获取舒张期室间隔基底部组织多普勒收缩期峰值速度(s)、舒张早期峰值速度、舒张晚期峰值速度(a).结果 异常组A值、a峰、s峰明显高于正常组,差异有统计学意义(P<0.05,P<0.01).

  14. Microlesions induced by microcavitation during contrast echocardiography

    Science.gov (United States)

    Miller, Douglas; Li, Peng; Gordon, David; Armstrong, William

    2001-05-01

    The purpose of this study was to search for histologically identifiable lesions associated with myocardial contrast echocardiography (MCE) in rats. Diagnostic ultrasound scans with 1:4 end-systolic triggering provided a short-axis view of the left ventricle in rats at 1.5 MHz with 1.45-μs pulses of 1.7 Mechanical Index. Two relatively high doses (500 μl/kg) of OptisonTM ultrasound contrast agent were given 5 min apart during 10 min of MCE. One day after scanning, rats were sacrificed and the hearts fixed for histology. Slides were scored blind by a pathologist, and photomicrographs in the anterior half of the heart sections were characterized by digital image analysis. Microlesions identified by inflammatory infiltrates were scattered primarily over the anterior half of the sections. Pathologically, there was inflammatory cell infiltration in areas of 0.6+/-0.5% of the sections for shams and 3.6+/-3.6% for MCE (P<0.01). Analysis of the photographs from the anterior wall found microlesion areas of 0.5+/-0.8% for shams and 7.4+/-5.0% for MCE (P<0.02). Diagnostic MCE at high Mechanical Index has a potential for causing microscale lesions in the myocardium by nucleation of microcavitation. [Work supported by NIH Grant EB0338.

  15. Healed perivalvular abscess: Incidental finding on transthoracic echocardiography

    Directory of Open Access Journals (Sweden)

    Vishnu Datt

    2014-01-01

    Full Text Available A 36-year-old male patient presented with the complaints of palpitations and breathlessness. Preoperative transthoracic echocardiography (TTE revealed a bicuspid aortic valve; severe aortic regurgitation with dilated left ventricle (LV and mild LV systolic dysfunction (ejection fraction 50%. He was scheduled to undergo aortic valve replacement. History was not suggestive of infective endocarditis (IE. Preoperative TTE did not demonstrate any aortic perivalvular abscess. Intraoperative transesophageal echocardiography (TEE examination using the mid-esophageal (ME long-axis view, showed an abscess cavity affecting the aortic valve, which initially was assumed to be a dissection flap, but later confirmed to be an abscess cavity by color Doppler examination. The ME aortic valve short-axis view showed two abscesses; one was at the junction of the non-coronary and left coronary commissure and the other one above the right coronary cusp. Intraoperatively, these findings were confirmed by the surgeons. The case report demonstrates the superiority of TEE over TTE in diagnosing perivalvular abscesses.

  16. High-sensitive cardiac Troponin T is superior to echocardiography in predicting 1-year mortality in patients with SIRS and shock in intensive care

    Directory of Open Access Journals (Sweden)

    Bergenzaun Lill

    2012-09-01

    Full Text Available Abstract Background Left ventricular (LV dysfunction is well documented in the critically ill. We assessed 1-year mortality in relation to cardiac biomarkers and LV function parameters by echocardiography in patients with shock. Methods A prospective, observational, cohort study of 49 patients. B-natriuretic peptide (BNP, high-sensitive troponin T (hsTNT and transthoracic echocardiography (TTE were assessed within 12 h of study inclusion. LV systolic function was measured by ejection fraction (LVEF, mean atrioventricular plane displacement (AVPDm, peak systolic tissue Doppler velocity imaging (TDIs and velocity time integral in the LV outflow tract (LVOT VTI. LV diastolic function was evaluated by transmitral pulsed Doppler (E, A, E/A, E-deceleration time, tissue Doppler indices (é, á, E/é and left atrial volume (La volume. APACHE II (Acute Physiology and Chronic Health Evaluation and SOFA (Sequential Organ Failure Assessment scores were calculated. Results hsTNT was significantly higher in non-survivors than in survivors (60 [17.0-99.5] vs 168 [89.8-358] ng/l, p = 0.003. Other univariate predictors of mortality were APACHE II (p = 0.009, E/é (p = 0.023, SOFA (p = 0.024 and age (p = 0.031. Survivors and non-survivors did not differ regarding BNP (p = 0.26 or any LV systolic function parameter (LVEF p = 0.87, AVPDm p = 0.087, TDIs p = 0.93, LVOT VTI p = 0.18. Multivariable logistic regression analysis identified hsTNT (p = 0.010 as the only independent predictor of 1-year mortality; adjusted odds ratio 2.0 (95% CI 1.2- 3.5. Conclusions hsTNT was the only independent predictor of 1-year mortality in patients with shock. Neither BNP nor echocardiographic parameters had an independent prognostic value. Further studies are needed to establish the clinical significance of elevated hsTNT in patients in shock.

  17. Significant Reduction in Mitral Regurgitation Volume Is the Main Contributor for Increase in Systolic Forward Flow in Patients with Functional Mitral Regurgitation after Transcatheter Aortic Valve Replacement: Hemodynamic Analysis Using Echocardiography.

    Science.gov (United States)

    Itabashi, Yuji; Shibayama, Kentaro; Mihara, Hirotsugu; Utsunomiya, Hiroto; Berdejo, Javier; Arsanjani, Reza; Siegel, Robert; Chakravarty, Tarun; Jilaihawi, Hasan; Makkar, Raj R; Shiota, Takahiro

    2015-11-01

    Reduction in mitral regurgitation (MR) after transcatheter aortic valve replacement (TAVR) has previously been reported. However, the hemodynamic effects of TAVR in patients with MR have not been previously evaluated. We analyzed 571 patients who underwent TAVR from December 2010 to December 2013. We studied 20 patients with moderate or severe preprocedural functional mitral regurgitation (FMR) who also had a follow-up transthoracic echocardiography (TTE) examination between 90 and 360 days (median 213 days) after TAVR (Significant FMR Group). We also studied age- and gender-matched 20 patients with mild or lesser MR (Nonsignificant MR Group). Left ventricular functional measurements were assessed using echocardiography before and after TAVR. Left ventricular outflow tract stroke volume measurements using pulsed-wave Doppler (SVLVOT ) were calculated as a representative of systolic forward flow, and stroke volume by the Simpson's method (SVSimpson ) was calculated as a parameter of degree of LV contraction. MR grade improved in 22 of 40 patients after TAVR. In both groups, BNP level decreased, left ventricular ejection fraction increased, and SVLVOT increased after TAVR. SVSimpson increased in the Nonsignificant MR Group and remained unchanged in the Significant FMR Group. Vena contracta width of MR (MRVC) decreased in the Significant FMR Group. Using multivariable analysis in the Significant FMR Group, the increase in SVLVOT significantly correlated with the decrease in MRVC (P FMR. In these patients, increase in SVLVOT after TAVR was associated with decrease in severity of MR. © 2015, Wiley Periodicals, Inc.

  18. Ecocardiografía de contraste: historia, características de las microburbujas y técnicas instrumentales Contrast echocardiography: history, micro bubble characteristics and instrumental techniques

    Directory of Open Access Journals (Sweden)

    Carlos Cubides

    Full Text Available Este artículo describe la historia de la ecocardiografía de contraste, las características físicas de las microburbujas de los agentes de contraste, las principales herramientas instrumentales (índice mecánico, foco y enfoque, número de imágenes por segundo y las técnicas ecocardiográficas (segunda armónica, armónica de fusión, segunda armónica de pulso invertido, imagen intermitente, angio y densitometría acústica actualmente disponibles para uso clínico.This article describes the history of contrast echocardiography, the physical characteristics of the contrast agents’ micro bubbles, the main instrumental tools (mechanical index, focus and focusing, frame rate, and the echocardiography techniques (second harmonic imaging, fusion harmonic, power pulse inversion imaging, triggered imaging, intermittent harmonic power Doppler, color power angio and acoustic densitometry, actually available for clinical use.

  19. Pediatric echocardiography laboratory organization and clinical productivity.

    Science.gov (United States)

    Lai, Wyman W; Srivastava, Shubhika; Cohen, Meryl S; Frommelt, Peter C; Allada, Vivek

    2013-10-01

    The American Society of Echocardiography's Committee on Pediatric Echocardiography Laboratory Productivity (C-PELP) was formed to study the organizational and productivity issues particular to academic pediatric echocardiography laboratories. After much deliberation, the committee chose studies per physician full-time equivalent per day --the average number of studies interpreted per day by a full-time echocardiography physician dedicated to the laboratory -as the primary measure of physician productivity. A survey was sent to 74 North American pediatric echocardiography laboratory directors. The aims of the survey were to (1) determine the annual laboratory volume and types of echocardiographic studies performed, (2) define the average number of studies performed by a pediatric cardiac sonographer in a year, (3) assess the productivity of echocardiography physicians, and (4) identify factors (programmatic or laboratory related) that affect clinical productivity. There were 54 responses to the C-PELP 2011 survey. The average number of studies per physician full-time equivalent per day was 15.0 + 4.5 (median, 13.8; range, 6.2 -27.1), and the average number of studies performed per year by a sonographer was 1,297 + 326 (median, 1,279; range 717 -2,475). These figures were not adjusted for case complexity, time requirement for transesophageal echocardiography, level of expertise, or availability of sonographer assistance. Moreover, the issues of study quality and accuracy were not addressed. The C-PELP 2011 survey gathered important information on the current organization and staffing of academic pediatric echocardiography laboratories, but the committee did not attempt to craft guidelines or recommendations on staffing requirements. The results of the survey, however, should provide a framework for additional investigation into the optimal structure and staffing of pediatric echocardiography laboratories. Copyright © 2013 American Society of Echocardiography

  20. Three-dimensional Echocardiography of Right Ventricular Function Correlates with Severity of Pediatric Pulmonary Hypertension.

    Science.gov (United States)

    Jone, Pei-Ni; Patel, Sonali S; Cassidy, Courtney; Ivy, David Dunbar

    2016-12-01

    Right ventricular function and biomarkers of B-type natriuretic peptide (BNP) and N-Terminal pro-BNP (NT pro-BNP) are used to determine the severity of right ventricular failure and outcomes from pulmonary hypertension. Real-time three-dimensional echocardiography (3DE) is a novel quantitative measure of the right ventricle and decreases the geometric assumptions from conventional two-dimensional echocardiography (2DE). We correlated right ventricular functional measures using 2DE and single-beat 3DE with biomarkers and hemodynamics to determine the severity of pediatric pulmonary hypertension. We retrospectively evaluated 35 patients (mean age 12.67 ± 5.78 years) with established pulmonary hypertension who had echocardiograms and biomarkers on the same day. Ten out of 35 patients had hemodynamic evaluation within 3 days. 2DE evaluation included tricuspid annular plane systolic excursion (TAPSE), right ventricular myocardial performance index from tissue Doppler imaging (RV TDI MPI), and right ventricular fractional area change (FAC). Three-dimensional echocardiography evaluation included right ventricular ejection fraction (EF), end-systolic volume, and end-diastolic volume. The quality of the 3DE was graded as good, fair, or poor. Pearson correlation coefficients were utilized to evaluate between biomarkers and echocardiographic parameters and between hemodynamics and echocardiography. Three-dimensional echocardiography and FAC correlated significantly with BNP and NT pro-BNP. TAPSE and RV TDI MPI did not correlate significantly with biomarkers. 3D right ventricular EF correlated significantly with hemodynamics. Two-dimensional echocardiography did not correlate with hemodynamics. Single-beat 3DE is a noninvasive, feasible tool in the quantification of right ventricular function and maybe more accurate than conventional 2DE in evaluating severity of pulmonary hypertension. © 2016 Wiley Periodicals, Inc.

  1. Differential doppler heterodyning technique

    DEFF Research Database (Denmark)

    Lading, Lars

    1971-01-01

    Measuring velocity without disturbing the moving object is possible by use of the laser doppler heterodyning technique. Theoretical considerations on the doppler shift show that the antenna property of the photodetector can solve an apparent conflict between two different ways of calculating...... the detected doppler frequency. It is found that the doppler frequency for this particular setup is independent of the direction of detection. Investigations of the signal-to-noise ratio (SNR) show that the maximum SNR-considering the optical setup-is obtained by measuring the frequency difference between two...

  2. Doppler Lidar for Wind Measurements on Venus

    Science.gov (United States)

    Singh, Upendra N.; Emmitt, George D.; Yu, Jirong; Kavaya, Michael J.

    2010-01-01

    NASA Langley Research Center has a long history of developing 2-micron laser transmitter for wind sensing. With support from NASA Laser Risk Reduction Program (LRRP) and Instrument Incubator Program (IIP), NASA Langley Research Center has developed a state-of-the-art compact lidar transceiver for a pulsed coherent Doppler lidar system for wind measurement. The transmitter portion of the transceiver employs the high-pulse-energy, Ho:Tm:LuLiF, partially conductively cooled laser technology developed at NASA Langley. The transceiver is capable of 250 mJ pulses at 10 Hz. It is very similar to the technology envisioned for coherent Doppler lidar wind measurements from Earth and Mars orbit. The transceiver is coupled to the large optics and data acquisition system in the NASA Langley VALIDAR mobile trailer. The large optics consists of a 15-cm off-axis beam expanding telescope, and a full-hemispheric scanner. Vertical and horizontal vector winds are measured, as well as relative backscatter. The data acquisition system employs frequency domain velocity estimation and pulse accumulation. It permits real-time display of the processed winds and archival of all data. This lidar system was recently deployed at Howard University facility in Beltsville, Mary-land, along with other wind lidar systems. Coherent Doppler wind lidar ground-based wind measurements and comparisons with other sensors will be presented. A simulation and data product for wind measurement at Venus will be presented.

  3. Dynamic three-dimensional reconstruction of the heart by transesophageal echocardiography

    Directory of Open Access Journals (Sweden)

    Veiga Maria de Fátima

    1999-01-01

    Full Text Available OBJECTIVE: To evaluate echocardiography accuracy in performing and obtaining images for dynamical three-dimensional (3D reconstruction. METHODS: Three-dimensional (3D image reconstruction was obtained in 20 consecutive patients who underwent transesophageal echocardiography. A multiplanar 5 MHz transducer was used for 3D reconstruction. RESULTS: Twenty patients were studied consecutively. The following cardiac diseases were present: valvar prostheses-6 (2 mitral, 2 aortic and 2 mitral and aortic; mitral valve prolapse- 3; mitral and aortic disease - 2; aortic valve disease- 5; congenital heart disease- 3 (2 atrial septal defect- ASD - and 1 transposition of the great arteries -TGA; arteriovenous fistula- 1. In 7 patients, color Doppler was also obtained and used for 3D flow reconstruction. Twenty five cardiac structures were acquired and 60 reconstructions generated (28 of mitral valves, 14 of aortic valves, 4 of mitral prostheses, 7 of aortic prostheses and 7 of the ASD. Fifty five of 60 (91.6% reconstructions were considered of good quality by 2 independent observers. The 11 reconstructed mitral valves/prostheses and the 2 reconstructed ASDs provided more anatomical information than two dimensional echocardiography (2DE alone. CONCLUSION: 3D echocardiography using a transesophageal transducer is a feasible technique, which improves detection of anatomical details of cardiac structures, particularly of the mitral valve and atrial septum.

  4. The echocardiography of replacement heart valves

    Science.gov (United States)

    2016-01-01

    This is a practical description of how replacement valves are assessed using echocardiography. Normal transthoracic appearances including normal variants are described. The problem of differentiating normal function, patient–prosthesis mismatch and pathological obstruction in aortic replacement valves with high gradients is discussed. Obstruction and abnormal regurgitation is described for valves in the aortic, mitral and right-sided positions and when to use echocardiography in suspected infective endocarditis. The roles of transoesophageal and stress echocardiography are described and finally when other imaging techniques may be useful. PMID:27600454

  5. Modifications of Oxygen Saturation During Transesophageal Echocardiography.

    Science.gov (United States)

    Macor, Franco; Zottarel, Gabriella; Antonini-Canterin, Francesco; Mimo, Renata; Pavan, Daniela; Cervesato, Eugenio; Nicolosi, Gianluigi; Zanuttini, Domenico

    1997-05-01

    The present study was designed: (1) to establish the effects of transesophageal echocardiography (TEE) on arterial oxygen saturation (SAO(2)%); (2) to verify the possible clinical consequences of this phenomenon; and (3) to study the possibility of predicting modifications of SAO(2)% by clinical or hemodynamic variables or by specific factors related to the TEE procedure. We prospectively studied 116 unselected patients, aged 61 +/- 12 years, who underwent diagnostic TEE for various clinical indications. Thirty-seven patients had mitral valve disease, 19 aortic valve disease, 14 combined mitroaortic disease, 8 congenital heart disease, and 38 other cardiovascular diseases. Eight patients were affected by chronic obstructive pulmonary disease. Ninety-seven patients were sedated by 4 +/- 2 mg of diazepam IV SAO(2)% (5-min average) (Ohmeda Biox 3700 pulse oxymeter finger probe), heart rate (HR), and blood pressure (BP) were considered during baseline transthoracic examination, after pharmacological sedation but before the introduction of the probe, and finally during TEE. Neither clinical complications nor major arrhythmias were observed. Baseline SAO(2)%, HR and BP were, respectively, 93.6 +/- 3.3%, 76 +/- 14 beats/min, and 129 +/- 20/75 +/- 10 mmHg. Pharmacological sedation did not modify SAO(2)%, HR, and BP (P > 0.1). During TEE a small but significant reduction in SAO(2)% by an average of 1.2 +/- 3.2% was observed (P 0.1 for both systolic and diastolic). The changes of SAO(2)% and HR were not interrelated and were not related to the duration of the procedure and to any of the clinical and hemodynamic variables taken into consideration. TEE can induce a small but significant drop in SAO(2)% and a small increase in HR even without any clinical relevance. No clinical or hemodynamic variable or specific factors related to the TEE procedure were related to these changes.

  6. Tendinopathy and Doppler activity

    DEFF Research Database (Denmark)

    Boesen, M I; Koenig, M J; Torp-Pedersen, S

    2006-01-01

    Intratendinous Doppler activity has been interpreted as an equivalent of neovessels in the Achilles tendon and as a sign of tendinosis (AT).......Intratendinous Doppler activity has been interpreted as an equivalent of neovessels in the Achilles tendon and as a sign of tendinosis (AT)....

  7. Serial measurements of exercise performance in pediatric heart transplant patients using stress echocardiography.

    Science.gov (United States)

    Yeung, Joanne P; Human, Derek G; Sandor, George G S; De Souza, Astrid M; Potts, James E

    2011-05-01

    Heart transplantation is an increasingly acceptable therapeutic option for children with end-stage and complex congenital heart disease. With advances in surgery, immunosuppression, and follow-up care, functional outcomes need to be evaluated. We report the results of serial exercise testing performed using stress echocardiography in a cohort of pediatric HTP. HTP (n = 7) exercised on a semi-recumbent ergometer to volitional fatigue. Echocardiography-Doppler measurements, HR, and blood pressure were taken at rest and during staged exercise. Results were compared with healthy CON (n = 12). HTP did significantly less work during exercise (940 vs. 1218 J/kg, p HTP had a lower SF at peak exercise (48% vs. 52%, p HTP. HTP are able to exercise safely; however, their exercise tolerance is reduced, and hemodynamics and contractility are diminished. Over time, their hemodynamics and left ventricular function have remained relatively constant.

  8. Combination of contrast with stress echocardiography: A practical guide to methods and interpretation

    Directory of Open Access Journals (Sweden)

    Marwick Thomas H

    2004-08-01

    Full Text Available Abstract Contrast echocardiography has an established role for enhancement of the right heart Doppler signals, the detection of intra-cardiac shunts, and most recently for left ventricular cavity opacification (LVO. The use of intravenously administered micro-bubbles to traverse the myocardial microcirculation in order to outline myocardial viability and perfusion has been the source of research studies for a number of years. Despite the enthusiasm of investigators, myocardial contrast echocardiography (MCE has not attained routine clinical use and LV opacification during stress has been less widely adopted than the data would support. The purpose of this review is to facilitate an understanding of the involved imaging technologies that have made this technique more feasible for clinical practice, and to guide its introduction into the practice of the non-expert user.

  9. Usefulness of speckle tracking echocardiography in hypertensive crisis and the effect of medical treatment.

    Science.gov (United States)

    Alam, Mahboob; Zhang, Lily; Stampehl, Mark; Lakkis, Nasser; Dokainish, Hisham

    2013-07-15

    The acute impact of hypertensive crisis, and changes after treatment, on left ventricular (LV) systolic and diastolic function using comprehensive echocardiography, including speckle tracking, has not been well characterized. Thirty consecutive patients admitted to the hospital from the emergency room with hypertensive crisis underwent Doppler echocardiography at baseline and after blood pressure optimization. The mean age of the patients was 54 ± 13 years, with 19 men (63%). The most common presenting symptoms included dyspnea (70%), chest pain (43%), and altered mental status (13%). Mean systolic and diastolic blood pressures at presentation were 198 ± 12 and 122 ± 12 mm Hg, decreasing to 143 ± 15 and 77 ± 12 mm Hg (p hypertensive crisis and significantly improved after medical treatment. LV diastolic function, assessed using conventional and speckle-tracking parameters, was also depressed and significantly improved after treatment.

  10. [Left ventricular functions in patients with cardiac syndrome X: a tissue Doppler study].

    Science.gov (United States)

    Yazici, Hüseyin Uğur; Sen, Nihat; Tavil, Yusuf; Hizal, Fatma; Turfan, Murat; Poyraz, Fatih; Boyaci, Bülent; Cengel, Atiye

    2009-12-01

    The aim of the study was to compare diagnostic accuracy of tissue Doppler imaging (TDI) and conventional Doppler echocardiography in diagnosis of left ventricular diastolic dysfunction in patients with cardiac syndrome X. Our study was designed as cross-sectional study. In our study, we compared 35 patients with cardiac syndrome X (19 female, mean age 47.2+/- 7.3 years) with 33 healthy persons as control group (18 female, mean age 49.5+/- 7.1 years) with no coronary artery disease and having no ischemic complaints or findings at exercise test. Left ventricular systolic function was found by considering mean values of modified Simpson method for left ventricular ejection fraction and TDI assessment of systolic wave peak velocity. The diastolic function of left ventricle was assessed with conventional echocardiography and TDI. Unpaired t test for independent samples or Mann-Whitney U test were used for comparison of continuous variables, Chi square test - for comparison of categorical variables. To define the capability of predicting diastolic dysfunction for conventional Doppler echocardiography and tissue Doppler imaging ROC curve analysis was applied. Left ventricular ejection fraction and systolic wave peak velocity were similar for both groups. Conventional Doppler echocardiographic measurements for left ventricular diastolic functions delineated the more frequent presence of diastolic dysfunction in cardiac syndrome X group As compared with controls (48% vs 18%; p<0.01). When both methods used for assessing diastolic dysfunction, it was found more apparent (66% vs 24%; p<0.01). When ROC curve was drawn for conventional Doppler echocardiography the AUC was 0.623, the sensitivity and the specificity were 49% and 76%, respectively. When the same was done for TDI the values were AUC=0.669, the sensitivity - 66% and the specificity - 68%. Our study revealed the deterioration of left ventricular diastolic function in patients with cardiac syndrome X. We found TDI

  11. Superharmonic microbubble Doppler effect in ultrasound therapy

    Science.gov (United States)

    Pouliopoulos, Antonios N.; Choi, James J.

    2016-08-01

    The introduction of microbubbles in focused ultrasound therapies has enabled a diverse range of non-invasive technologies: sonoporation to deliver drugs into cells, sonothrombolysis to dissolve blood clots, and blood-brain barrier opening to deliver drugs into the brain. Current methods for passively monitoring the microbubble dynamics responsible for these therapeutic effects can identify the cavitation position by passive acoustic mapping and cavitation mode by spectral analysis. Here, we introduce a new feature that can be monitored: microbubble effective velocity. Previous studies have shown that echoes from short imaging pulses had a Doppler shift that was produced by the movement of microbubbles. Therapeutic pulses are longer (>1 000 cycles) and thus produce a larger alteration of microbubble distribution due to primary and secondary acoustic radiation force effects which cannot be monitored using pulse-echo techniques. In our experiments, we captured and analyzed the Doppler shift during long therapeutic pulses using a passive cavitation detector. A population of microbubbles (5  ×  104-5  ×  107 microbubbles ml-1) was embedded in a vessel (inner diameter: 4 mm) and sonicated using a 0.5 MHz focused ultrasound transducer (peak-rarefactional pressure: 75-366 kPa, pulse length: 50 000 cycles or 100 ms) within a water tank. Microbubble acoustic emissions were captured with a coaxially aligned 7.5 MHz passive cavitation detector and spectrally analyzed to measure the Doppler shift for multiple harmonics above the 10th harmonic (i.e. superharmonics). A Doppler shift was observed on the order of tens of kHz with respect to the primary superharmonic peak and is due to the axial movement of the microbubbles. The position, amplitude and width of the Doppler peaks depended on the acoustic pressure and the microbubble concentration. Higher pressures increased the effective velocity of the microbubbles up to 3 m s-1, prior to the onset of

  12. Micro-Doppler processing for ultra-wideband radar data

    Science.gov (United States)

    Smith, Graeme E.; Ahmad, Fauzia; Amin, Moeness G.

    2012-06-01

    In this paper, we describe an operational pulse Doppler radar imaging system for indoor target localization and classification, and show how a target's micro-Doppler signature (μDS) can be processed when ultra-wideband (UWB) waveforms are employed. Unlike narrowband radars where time-frequency signal representations can be applied to reveal the target time-Doppler frequency signatures, the UWB system permits joint range-time-frequency representation (JRTFR). JRTFR outputs the data in a 3D domain representing range, frequency, and time, allowing both the μDS and high range resolution (HRR) signatures to be observed. We delineate the relationship between the μDS and the HRR signature, showing how they would form a complimentary joint feature for classification. We use real-data to demonstrate the effectiveness of the UWB pulse-Doppler radar, combined with nonstationary signal analyses, in gaining valuable insights into human positioning and motions.

  13. Doppler Compensation by using of Segmented Match Filter

    Directory of Open Access Journals (Sweden)

    Nader Ghadimi

    2008-09-01

    Full Text Available Match filter is one of the important parts of radar receiver. By using of Match Filter, the signal to noise ratio can be maximized so that the probability of detection is increased. Match Filter can be used as a pulse compression filter in radar receiver. Binary phase code is one of the pulse compression methods that, the compression can be down with a Match Filter in the receiver. Doppler effect is one of the problems that degrade the performance of Match Filter. In this paper, two methods “Mixer Array” and “Segmented Match Filter” are proposed for Doppler compensation. The operation of these two methods as Doppler compensation techniques are considered theoretically. The simulation is used to demonstrate the Doppler compensation performance of new techniques compared to conventional methods.

  14. Two dimensional and Doppler echocardiographic evaluation of patients presenting at Obafemi Awolowo University Teaching Hospitals Complex Ile Ife Nigeria a prospective study of 2501 subjects

    Directory of Open Access Journals (Sweden)

    Adebayo RA

    2013-07-01

    Full Text Available Rasaaq Ayodele Adebayo,1 Patience Olayinka Akinwusi,2 Michael Olabode Balogun,1 Anthony Olubunmi Akintomide,1 Victor Oladeji Adeyeye,1 Olugbenga Olusola Abiodun,1 Luqman Adeleke Bisiriyu,3 Suraj Adefabi Ogunyemi,1 Ebenezer Adekunle Ajayi,4 Olufemi Eyitayo Ajayi,1 Adebayo Tolulope Oyedeji5 1Cardiology Unit, Department of Medicine, Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife, Osun State, 2Cardiology Unit, Department of Medicine, Osun State University, Osogbo, Osun State, 3Department of Demography and Social Statistics, Obafemi Awolowo University, Ile-Ife, Osun State, 4Cardiology Unit, Department of Medicine, Ekiti State University Teaching Hospital, Ado-Ekiti, Ekiti State, 5Cardiology Unit, Department of Medicine, LAUTECH Teaching Hospital, Osogbo, Osun State, Nigeria Background: Echocardiography remains a key noninvasive cardiac investigative tool in the management of patients, especially in a developing economy like Nigeria. In this study, we investigated the indications for transthoracic echocardiography and spectrum of cardiac disease found in patients referred to our cardiac unit for echocardiography. Methods: A prospective two-dimensional, pulsed, continuous, and color-flow Doppler echocardiographic evaluation was done using the transthoracic approach in 2501 patients over an eight-year period. Univariate data analysis was performed for mean age, gender, clinical indications, and diagnoses. Results: The subject age range was less than 12 months to 97 years (mean 52.39 years. There were 1352 (54.06% males and 1149 (45.94% females. The most common indication for echocardiography was hypertension (52.1% followed by congestive cardiac failure (13.9%. Others were for screening (6.1%, arrhythmias (5%, cerebrovascular disease (5%, chest pain (3.3%, chronic kidney disease (3.2%, congenital heart disease (2.6%, cardiomyopathy (1.8%, rheumatic heart disease (1.7%, diabetes mellitus (1.3%, thyrocardiac disease (1.2%, ischemic heart

  15. Fetal echocardiography in ectopia cordis.

    Science.gov (United States)

    Repondek-Liberska, M; Janiak, K; Wloch, A

    2000-01-01

    Ectopia cordis is an extremely rare congenital abnormality occurring in 5.5 to 7.9 per 1 million live births with high lethality. Between January 1995 and October 1997 eight cases of ectopia cordis were diagnosed at our institute before birth. On the basis of echocardiography the fetal heart anatomy was categorized as either normal heart anatomy (NHA; n = 3) or congenital heart defect (CHD; n = 5). In the majority of cases (seven of eight) other abnormalities were present. Some reports have described ectopia cordis being diagnosed in the first trimester of pregnancy. In our study group the average gestational age at diagnosis was 26 weeks. The prenatal diagnosis of isolated ectopia cordis is easy; counseling the patient, the perinatal management including term, place, and method of delivery, and optimal care of the newborn are more difficult. Ectopia cordis is a malformation that pediatricians rarely encounter, even at pediatric cardiology centers. Much more frequently it is a problem for sonographers and obstetricians; however, pediatric cardiologists should be aware of diagnostic algorithm for such cases, especially when additional abnormalities are present.

  16. Transoesophageal echocardiography during liver transplantation

    Institute of Scientific and Technical Information of China (English)

    Lesley; De; Pietri; Federico; Mocchegiani; Chiara; Leuzzi; Roberto; Montalti; Marco; Vivarelli; Vanni; Agnoletti

    2015-01-01

    Liver transplantation(LT) has become the standard of care for patients with end stage liver disease. The allocation of organs, which prioritizes the sickest patients, has made the management of liver trans-plant candidates more complex both as regards their comorbidities and their higher risk of perioperative complications. Patients undergoing LT frequently display considerable physiological changes during the pro-cedures as a result of both the disease process and the surgery. Transoesophageal echocardiography(TEE), which visualizes dynamic cardiac function and overall contractility, has become essential for perioperative LT management and can optimize the anaesthetic management of these highly complex patients. More-over, TEE can provide useful information on volume status and the adequacy of therapeutic interventions and can diagnose early intraoperative complications, such as the embolization of large vessels or development of pulmonary hypertension. In this review, directed at clinicians who manage TEE during LT, we show why the procedure merits a place in challenging anaesthetic environment and how it can provide essential information in the perioperative management of compromised patients undergoing this very complex surgical procedure.

  17. Ultrasonic Doppler measurement of renal artery blood flow

    Science.gov (United States)

    Freund, W. R.; Beaver, W. L.; Meindl, J. D.

    1976-01-01

    Studies were made of (1) blood flow redistribution during lower body negative pressure (LBNP), (2) the profile of blood flow across the mitral annulus of the heart (both perpendicular and parallel to the commissures), (3) testing and evaluation of a number of pulsed Doppler systems, (4) acute calibration of perivascular Doppler transducers, (5) redesign of the mitral flow transducers to improve reliability and ease of construction, and (6) a frequency offset generator designed for use in distinguishing forward and reverse components of blood flow by producing frequencies above and below the offset frequency. Finally methodology was developed and initial results were obtained from a computer analysis of time-varying Doppler spectra.

  18. Transesophageal echocardiography in patients with cryptogenic cerebral ischemia

    Directory of Open Access Journals (Sweden)

    Dreger Henryk

    2009-03-01

    Full Text Available Abstract Background In about one third of all patients with cerebral ischemia, no definite cause can be identified (cryptogenic stroke. In many patients with initially suspected cryptogenic stroke, however, a cardiogenic etiology can eventually be determined. Hence, the aim of this study was to describe the prevalence of abnormal echocardiographic findings in a large number of these patients. Method Patients with cryptogenic cerebral ischemia (ischemic stroke, IS, and transient ischemic attack, TIA were included. The initial work-up included a neurological examination, EEG, cCT, cMRT, 12-lead ECG, Holter-ECG, Doppler ultrasound of the extracranial arteries, and transthoracic echocardiography. A multiplane transeophageal echocardiography (TEE, including i.v. contrast medium application [Echovist], Valsalva maneuver was performed in all patients Results 702 consecutive patients (380 male, 383 IS, 319 TIA, age 18–90 years were included. In 52.6% of all patients, TEE examination revealed relevant findings. Overall, the most common findings in all patients were: patent foramen ovale (21.7%, previously undiagnosed valvular disease (15.8%, aortic plaques, aortic valve sclerosis, atrial septal aneurysms, regional myocardial dyskinesia, dilated left atrium and atrial septal defects. Older patients (> 55 years, n = 291 and patients with IS had more relevant echocardiographic findings than younger patients or patients with TIA, respectively (p = 0.002, p = 0.003. The prevalence rates of PFO or ASD were higher in younger patients (PFO: 26.8% vs. 18.0%, p = 0.005, ASD: 9.6% vs. 4.9%, p = 0.014. Conclusion A TEE examination in cryptogenic stroke reveals contributing cardiogenic factors in about half of all patients. Younger patients had a higher prevalence of PFO, whereas older patients had more frequently atherosclerotic findings. Therefore, TEE examinations seem indicated in all patients with cryptogenic stroke – irrespective of age – because of

  19. Bedside echocardiography in internal medicine: which are the key questions and answers for our decision-making?

    Directory of Open Access Journals (Sweden)

    Chiara Cogliati

    2015-12-01

    Full Text Available The advent of portable equipment in the last years has brought ultrasound (US technology available at patient bedside, giving the opportunity to non-cardiologists to extend cardiac assessment based on physical examination. Bedside echocardiography is a question-driven examination, where simple and often dichotomous answers are searched. It is performed using phased-array probes and bi-dimensional images are visually evaluated to obtain information regarding cardiac size and function, presence of pericardial effusion, gross valvular diseases. Although this approach cannot in any case substitute a standard 2D color-Doppler echocardiography, bedside echocardiography has been demonstrated to maintain a good diagnostic accuracy when limited to basic questions, even in the hands of short-trained non cardiologist physicians. At present the bedside US approach is widely used in different settings and focused echocardiography takes part together with US explorations of lung, abdomen and deep veins in an integrated perspective that perfectly fits with the holistic approach of the internist. In this context we address two typical scenarios encountered in the internal medicine divisions - the patient presenting with dyspnea or nonpost- traumatic hypotension - showing the main questions we can ask to bedside echocardiography for a rapid identification of the determinants of symptoms and consequently for a therapeutic choice based on more objective evidence.

  20. A review of Doppler ultrasound quality assurance protocols and test devices.

    Science.gov (United States)

    Browne, Jacinta E

    2014-11-01

    In this paper, an overview of Doppler ultrasound quality assurance (QA) testing will be presented in three sections. The first section will review the different Doppler ultrasound parameters recommended by professional bodies for use in QA protocols. The second section will include an evaluation and critique of the main test devices used to assess Doppler performance, while the final section of this paper will discuss which of the wide range of test devices have been found to be most suitable for inclusion in Doppler QA programmes. Pulsed Wave Spectral Doppler, Colour Doppler Imaging QA test protocols have been recommended over the years by various professional bodies, including the UK's Institute of Physics and Engineering in Medicine (IPEM), the American Institute for Ultrasound in Medicine (AIUM), and the International Electrotechnical Commission (IEC). However, despite the existence of such recommended test protocols, very few commercial or research test devices exist which can measure the full range of both PW Doppler ultrasound and colour Doppler imaging performance parameters, particularly quality control measurements such as: (i) Doppler sensitivity (ii) colour Doppler spatial resolution (iii) colour Doppler temporal resolution (iv) colour Doppler velocity resolution (v) clutter filter performance and (vi) tissue movement artefact suppression. In this review, the merits of the various commercial and research test devices will be considered and a summary of results obtained from published studies which have made use of some of these Doppler test devices, such as the flow, string, rotating and belt phantom, will be presented.

  1. Assessment of mitral valve reserve capacity before and after percutaneous balloon valvuloplasty with isoproterenol stress echocardiography

    Institute of Scientific and Technical Information of China (English)

    LIU Pin-ming; FU Xiang-yang; L(U) Jun-hao; WU Qun; Yang Fu-qing

    2002-01-01

    Objective: To explore whether successful valvuloplasty increases mitral valve reserve capacity in patients with mitral stenosis. Methods: Thirty-eight patients with pure rheumatic mitral stenosis underwent isoproterenol stress echocardiography before and after successful percutaneous balloon valvuloplasty. The mitral valve area (by direct planimetry of two-dimensional echocardiography), mean transmitral pressure gradient (by continuous-wave Doppler echocardiography), and cardiac output (by M-mode echocardiography)were measured at rest and under isoproterenol infusion to achieve heart rate of different stages. Results :Between the measurements before and after valvuloplasty, significant differences were observed in the mitral valve area (0. 91±0.28 vs 1.87±0.23 cm2, P<0.01), mean transmitral pressure gradient (12.5±6.3 vs 3. 9±1.9 mmHg, P<0. 01) and cardiac output (3.93±1.44 vs 4. 73±1.01 L/min, P<O. 05) at rest. Before valvuloplasty, the mean transmitral pressure gradient increased significantly (P<0. 01) as heart rate increased, but there were no significant differences in the measurements of mitral valve area and cardiac output (both P>0. 05). In contrast, there was a significant increase after valvuloplasty in the mean transmitral pressure gradient (P<0. 01), but both mitral valve area and cardiac output further increased (both P<0. 01) as beart rate increased. Moreover, valvuloplasty decreased the mean transmitral pressure gradient at peak heart rate from 23.0 ±4. 5 to 7.75 ±2. 30 mmHg (P<0.01) under submaximal stress. Conclusion:Successful percutaneous balloon valvuloplasty soon causes a significant increase of mitral valve reserve capacity in patients with mitral stenosis, which is conspicuously manifested under condition of hemodynamic stress.Stress echocardiography provides a safe, feasible and non-invasive means of assessing the reserve capacity.

  2. Impact of electrical cardioversion for atrial fibrillation on left atrial appendage function and spontaneous echo contrast: characterization by simultaneous transesophageal echocardiography.

    Science.gov (United States)

    Grimm, R A; Stewart, W J; Maloney, J D; Cohen, G I; Pearce, G L; Salcedo, E E; Klein, A L

    1993-11-01

    This study assessed the function of the left atrial appendage in the pericardioversion period to gain insights into mechanisms involved in thromboembolism after cardioversion of atrial fibrillation. Systemic embolization associated with electrical cardioversion of atrial fibrillation is thought to originate from the left atrium or left atrial appendage, or both. However, the mechanism involved is poorly understood. We studied left atrial appendage function with transesophageal echocardiography in 20 patients with atrial fibrillation before and after successful electrical cardioversion. We measured left atrial appendage emptying and filling velocities by pulsed wave Doppler echocardiography, characterized Doppler emptying patterns, measured atrial appendage areas and assessed the presence or absence of spontaneous echo contrast or thrombus. Organized left atrial appendage function returned in 16 (80%) of 20 patients immediately after cardioversion. Atrial appendage emptying velocities before cardioversion were greater in patients without (0.39 +/- 0.02 m/s) than in those with (0.25 +/- 0.12 m/s) spontaneous echo contrast (p = 0.045). Furthermore, emptying velocities before cardioversion were significantly greater than late diastolic emptying velocities after cardioversion (0.31 +/- 0.15 vs. 0.14 +/- 0.12 m/s, p = 0.0001), as well as in both the group with (0.25 +/- 0.12 vs. 0.13 +/- 0.13 m/s, p = 0.001) and the group without (0.39 +/- 0.02 vs. 0.15 +/- 0.12 m/s, p = 0.01) spontaneous echo contrast. In addition, left atrial and atrial appendage spontaneous echo contrast developed in 4 of 20 patients and increased in intensity in 3 of 20 patients in the immediate postcardioversion period. Organized left atrial appendage function returns in most patients immediately after cardioversion of atrial fibrillation. However, its function is impaired compared with that before cardioversion. Furthermore, spontaneous echo contrast increased in 7 (35%) of 20 patients after

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

    Science.gov (United States)

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

    2014-04-01

    Although the "3 beat rule" is widely utiized to discriminate patent foramen ovale (PFO)-mediated right-to-left shunt (RTLS) from intrapulmonary RTLS using saline contrast transthoracic echocardiography (SCE), SCE diagnostic performance has yet to be validated using an invasive intracardiac standard. Percutaneous PFO occluder placement was recently shown to ameliorate hypoxia in patients with suspected PFO-mediated RTLS. We evaluated the ability of SCE to predict PFO presence and size using intracardiac echocardiography (ICE) as a gold standard in a hypoxic cohort. Sixty-three hypoxic patients with suspected PFO-mediated RTLS who underwent SCE at rest, with Valsalva maneuver, and with cough prior to ICE were evaluated retrospectively. PFO RTLS was defined by ICE findings including PFO anatomy, RTLS by saline contrast and color Doppler, and probe patency. SCE shunt severity and timing of left heart saline target appearance were compared to the presence of ICE-defined PFO RTLS. Forty-seven patients (75%) met criteria for PFO-mediated RTLS. A 4 beat cutoff for resting SCE provided optimal diagnostic performance for detection of PFO-mediated RTLS with a 71% sensitivity, 94% specificity, and 97% positive predictive value (PPV). Valsalva and cough maneuvers improved sensitivity compared to rest SCE (89% and 80%, respectively). Valsalva SCE shunt severity more accurately predicted PFO size than resting SCE. In contrast to the widely accepted "3 beat rule," resting SCE for the detection of PFO RTLS in a hypoxic population performs optimally using a 4-cycle cutoff with both excellent specificity and PPV. © 2013, Wiley Periodicals, Inc.

  4. The Doppler echocardiographic myocardial performance index predicts left-ventricular dilation and cardiac death after myocardial infarction

    DEFF Research Database (Denmark)

    Møller, J E; Søndergaard, E; Poulsen, S H

    2001-01-01

    To investigate the value of the Doppler-derived myocardial performance index to predict early left-ventricular (LV) dilation and cardiac death after a first acute myocardial infarction (AMI), Doppler echocardiography was performed within 24 h of hospital admission, on day 5, 1 and 3 months after.......63, (p or = 0.63 (relative risk 5.6, p or = II (relative risk 4.0, p = 0.04) to be independent predictors of cardiac death. Therefore......, we conclude that the Doppler echocardiographic myocardial performance index is a predictor of LV dilation and cardiac death after a first AMI....

  5. Quantification of resting myocardial blood flow velocity in normal humans using real-time contrast echocardiography. A feasibility study

    Directory of Open Access Journals (Sweden)

    Slordahl Stig

    2005-06-01

    Full Text Available Abstract Background Real-time myocardial contrast echocardiography (MCE is a novel method for assessing myocardial perfusion. The aim of this study was to evaluate the feasibility of a very low-power real-time MCE for quantification of regional resting myocardial blood flow (MBF velocity in normal human myocardium. Methods Twenty study subjects with normal left ventricular (LV wall motion and normal coronary arteries, underwent low-power real-time MCE based on color-coded pulse inversion Doppler. Standard apical LV views were acquired during constant IV. infusion of SonoVue®. Following transient microbubble destruction, the contrast replenishment rate (β, reflecting MBF velocity, was derived by plotting signal intensity vs. time and fitting data to the exponential function; y (t =A (1-e-β(t-t0 + C. Results Quantification was feasible in 82%, 49% and 63% of four-chamber, two-chamber and apical long-axis view segments, respectively. The LAD (left anterior descending artery and RCA (right coronary artery territories could potentially be evaluated in most, but contrast detection in the LCx (left circumflex artery bed was poor. Depending on localisation and which frames to be analysed, mean values of were 0.21–0.69 s-1, with higher values in medial than lateral, and in basal compared to apical regions of scan plane (p = 0.03 and p Conclusion Low-power real-time MCE did have the potential to give contrast enhancement for quantification of resting regional MBF velocity. However, the technique is difficult and subjected to several limitations. Significant variability in β suggests that this parameter is best suited for with-in patient changes, comparing values of stress studies to baseline.

  6. Accuracy of flow convergence estimates of mitral regurgitant flow rates obtained by use of multiple color flow Doppler M-mode aliasing boundaries: an experimental animal study.

    Science.gov (United States)

    Zhang, J; Jones, M; Shandas, R; Valdes-Cruz, L M; Murillo, A; Yamada, I; Kang, S U; Weintraub, R G; Shiota, T; Sahn, D J

    1993-02-01

    boundary with an aliasing velocity, of 102 cm/sec, (which was achieved by use of a 4 kHz pulse repetition frequency, a 3.75 MHz transducer, and no color baseline shift), provided the closest fit to the actual regurgitant flow rates (r = 0.99; y = 0.95x + 0.07). The averaged calculated flow rates from all aliasing velocities also resulted in excellent correlation (r = 0.97; y = 0.99x + 0.5). A hemispheric flow convergence method that is based on color Doppler M-mode echocardiography is a feasible and automatable method for quantifying mitral regurgitant rate.(ABSTRACT TRUNCATED AT 400 WORDS)

  7. Avaliação dos tumores hepáticos ao Doppler Doppler evaluation of liver tumors

    Directory of Open Access Journals (Sweden)

    Márcio Martins Machado

    2004-10-01

    Full Text Available Os avanços recentes na ultra-sonografia têm ampliado a possibilidade de detecção de tumores hepáticos. Isto tem auxiliado na perspectiva de melhora do prognóstico destes pacientes, à medida que novas técnicas terapêuticas têm surgido. Neste artigo os autores relatam achados ao Doppler que podem auxiliar na identificação e caracterização dos tumores hepáticos, avaliando dados do Doppler colorido, pulsado e do Doppler de amplitude ("power Doppler". Fazem, também, referência a novas modalidades de imagem, como o uso da harmônica.Recent advances in ultrasound have optimized the detection of liver tumors and helped to improve the prognosis of patients with this condition as newly developed and improved therapeutic modalities have been established. The authors review important Doppler findings which may help in the identification and characterization of some hepatic tumors through the evaluation of color Doppler, pulsed Doppler and power Doppler features. New imaging methods such as the use of harmonics imaging are also reviewed.

  8. Target heart rate to determine the normal value of coronary flow reserve during dobutamine stress echocardiography

    Directory of Open Access Journals (Sweden)

    Rousse Maria G

    2011-04-01

    Full Text Available Abstract Background The determination of coronary flow reserve (CFR is an essential concept at the moment of decision-making in ischemic heart disease. There are several direct and indirect tests to evaluate this parameter. In this sense, dobutamine stress echocardiography is one of the pharmacological method most commonly used worldwide. It has been previously demonstrated that CFR can be determined by this technique. Despite our wide experience with dobutamine stress echocardiography, we ignored the necessary heart rate to consider sufficient the test for the analysis of CFR. For this reason, our main goal was to determine the velocity of coronary flow in each stage of dobutamine stress echocardiography and the heart rate value necessary to double the baseline values of coronary flow velocity in the territory of the left anterior descending (LAD coronary artery. Methods A total of 33 consecutive patients were analyzed. The patients included had low risk for coronary artery disease. All the participants underwent dobutamine stress echocardiography and coronary artery flow velocity was evaluated in the distal segment of LAD coronary artery using transthoracic color-Doppler echocardiography. Results The feasibility of determining CFR in the territory of the LAD during dobutamine stress echocardiography was high: 31/33 patients (94%. Mean CFR was 2.67 at de end of dobutamine test. There was an excellent concordance between delta HR (difference between baseline HR and maximum HR and the increase in the CFR (correlation coefficient 0.84. In this sense, we found that when HR increased by 50 beats, CFR was ≥ 2 (CI 93-99.2%. In addition, 96.4% of patients reached a CFR ≥ 2 (IC 91.1 - 99% at 75% of their predicted maximum heart rate. Conclusions We found that the feasibility of dobutamine stress echocardiography to determine CFR in the territory of the LAD coronary artery was high. In this study, it was necessary to achieve a difference of 50 bpm

  9. 2010 Canadian Cardiovascular Society/Canadian Society of Echocardiography Guidelines for Training and Maintenance of Competency in Adult Echocardiography.

    Science.gov (United States)

    Burwash, Ian G; Basmadjian, Arsene; Bewick, David; Choy, Jonathan B; Cujec, Bibiana; Jassal, Davinder S; MacKenzie, Scott; Nair, Parvathy; Rudski, Lawrence G; Yu, Eric; Tam, James W

    2011-01-01

    Guidelines for the provision of echocardiography in Canada were jointly developed and published by the Canadian Cardiovascular Society and the Canadian Society of Echocardiography in 2005. Since their publication, recognition of the importance of echocardiography to patient care has increased, along with the use of focused, point-of-care echocardiography by physicians of diverse clinical backgrounds and variable training. New guidelines for physician training and maintenance of competence in adult echocardiography were required to ensure that physicians providing either focused, point-of-care echocardiography or comprehensive echocardiography are appropriately trained and proficient in their use of echocardiography. In addition, revision of the guidelines was required to address technological advances and the desire to standardize echocardiography training across the country to facilitate the national recognition of a physician's expertise in echocardiography. This paper summarizes the new Guidelines for Physician Training and Maintenance of Competency in Adult Echocardiography, which are considerably more comprehensive than earlier guidelines and address many important issues not previously covered. These guidelines provide a blueprint for physician training despite different clinical backgrounds and help standardize physician training and training programs across the country. Adherence to the guidelines will ensure that physicians providing echocardiography have acquired sufficient expertise required for their specific practice. The document will also provide a framework for other national societies to standardize their training programs in echocardiography and will provide a benchmark by which competency in adult echocardiography may be measured.

  10. Micro-Doppler Ambiguity Resolution Based on Short-Time Compressed Sensing

    Directory of Open Access Journals (Sweden)

    Jing-bo Zhuang

    2015-01-01

    Full Text Available When using a long range radar (LRR to track a target with micromotion, the micro-Doppler embodied in the radar echoes may suffer from ambiguity problem. In this paper, we propose a novel method based on compressed sensing (CS to solve micro-Doppler ambiguity. According to the RIP requirement, a sparse probing pulse train with its transmitting time random is designed. After matched filtering, the slow-time echo signals of the micromotion target can be viewed as randomly sparse sampling of Doppler spectrum. Select several successive pulses to form a short-time window and the CS sensing matrix can be built according to the time stamps of these pulses. Then performing Orthogonal Matching Pursuit (OMP, the unambiguous micro-Doppler spectrum can be obtained. The proposed algorithm is verified using the echo signals generated according to the theoretical model and the signals with micro-Doppler signature produced using the commercial electromagnetic simulation software FEKO.

  11. The usefulness of contrast during exercise echocardiography for the assessment of systolic pulmonary pressure

    Directory of Open Access Journals (Sweden)

    Cordeiro Ana

    2008-10-01

    Full Text Available Abstract Background The systolic pulmonary artery pressure (PAPs can be accurately estimated, non-invasively, using continuous-wave Doppler (CWD ultrasound measurement of the peak velocity of a tricuspid regurgitant (TR jet. However, it is often difficult to obtain adequate tricuspid regurgitation signals for measurement of PAPs, what could lead to its underestimation. Therefore, utilization of air-blood-saline contrast has been implemented for the improvement of Doppler signal in several clinical contexts. It is now recommended in the evaluation of patients with pulmonary hypertension. Physical activity is severely restricted in patients with PAH, being exertional dypnea the most typical symptom. Exercise stress echo-Doppler imaging allows assessment of the response to exercise. It is an excellent screening test for patients with suspected PAH. Our purpose was to evaluate the value and accuracy of agitated saline with blood contrast echocardiography, in the improvement of the Doppler signal, to quantify PAPs during treadmill exercise-echocardiography. Purpose To evaluate the value of contrast echocardiography, using agitated saline with blood, in the improvement of the Doppler signal used to quantify the pulmonary artery systolic pressure during exercise. Methods From a total of 41 patients (pts, we studied 38 pts (93%, 35 women, aged 54 ± 12 years-old. 27 with the diagnosis of systemic sclerosis, 10 with history of pulmonary embolism and one patient with a suspected idiopathic PAH, who were referred to the Unity of Heart Failure and Pulmonary Hypertension for screening of PAH. According to the Unity protocol, a transthoracic echocardiogram was made, in left decubitus (LD, with evaluation of right ventricle-right atria gradient (RV/RAg. A peripheral venous access was obtained, with a 3-way stopcock and the patients were placed in orthostatism (O, with a new evaluation of RV/RAg. Exercise echocardiography (EE was begun, with evaluation of RV

  12. Three-dimensional Echocardiography in Valvular Heart Disease.

    Science.gov (United States)

    Kurklinsky, Andrew; Mankad, Sunil

    2012-01-01

    Recent technologic advances in 3-dimensional (3D) echocardiography, using parallel processing to scan a pyramidal volume, have allowed for a superior ability to describe valvular anatomy using both transthoracic and transesophageal echocardiography. Although still in evolution and at an early phase of adaptation with respect to its clinical application, 3D echocardiography has emerged as an important clinical tool in the assessment of valvular heart disease. Three-dimensional echocardiography provides unique perspectives of valvular structures by presenting "en face" views of valvular structures, allowing for a better understanding of the topographical aspects of pathology, and a refined definition of the spatial relationships of intracardiac structures. Three-dimensional echocardiography makes available indices not described by 2D echocardiography and has been demonstrated to be superior to 2D echocardiography in a variety of valvular disease scenarios. The information gained from 3D echocardiography has especially made an impact in guiding clinical decisions in the evaluation of mitral valve (MV) disease. The decision of early surgery in degenerative MV disease is based on the suitability of repair, and the suitability of repair is generally based on echocardiography. The superior understanding of MV anatomy afforded by 3D echocardiography has been shown to be quite valuable in this setting. This review will describe the contemporary use of 3D echocardiography in the assessment of valvular heart disease, including MV, aortic, tricuspid, and prosthetic valve abnormalities. This article illustrates how 3D echocardiography can complement current echocardiography techniques in the management of valvular heart disease.

  13. Tissue Doppler imaging reproducibility during exercise.

    Science.gov (United States)

    Bougault, V; Nottin, S; Noltin, S; Doucende, G; Obert, P

    2008-05-01

    Tissue Doppler imaging (TDI) is an echocardiographic technique used during exercising to improve the accuracy of a cardiovascular diagnostic. The validity of TDI requires its reproducibility, which has never been challenged during moderate to maximal intensity exercising. The present study was specifically designed to assess the transmitral Doppler and pulsed TDI reproducibility in 19 healthy men, who had undergone two identical semi-supine maximal exercise tests on a cycle ergometer. Systolic (S') and diastolic (E') tissue velocities at the septal and lateral walls as well as early transmitral velocities (E) were assessed during exercise up to maximal effort. The data were compared between the two tests at 40 %, 60 %, 80 % and 100 % of maximal aerobic power. Despite upper body movements and hyperventilation, good quality echocardiographic images were obtained in each case. Regardless of exercise intensity, no differences were noticed between the two tests for all measurements. The variation coefficients for Doppler variables ranged from 3 % to 9 % over the transition from rest to maximal exercise. The random measurement error was, on average, 5.8 cm/s for E' and 4.4 cm/s for S'. Overall, the reproducibility of TDI was acceptable. Tissue Doppler imaging can be used to accurately evaluate LV diastolic and/or systolic function for this range of exercise intensity.

  14. Three-dimensional echocardiography in valve disease.

    Science.gov (United States)

    Colombo, Chiara; Tamborini, Gloria; Pepi, Mauro; Alimento, Marina; Fiorentini, Cesare

    2007-01-01

    This review covers the role of three-dimensional (3D) echocardiography in the diagnosis of heart valve disease. Several factors have contributed to the evolution of this technique, which is currently a simple and routine method: rapid evolution in probe and computer technologies, demonstration that 3D data sets allowed more complete and accurate evaluation of cardiac structures, emerging clinical experience indicating the strong potential particularly in valve diseases, volume and function of the two ventricle measurements and several other fields. This report will review current and future applications of 3D echocardiography in mitral, aortic and tricuspid valve diseases underlying both qualitative (morphologic) and quantitative advantages of this technique.

  15. Simulation for transthoracic echocardiography of aortic valve

    Science.gov (United States)

    Nanda, Navin C.; Kapur, K. K.; Kapoor, Poonam Malhotra

    2016-01-01

    Simulation allows interactive transthoracic echocardiography (TTE) learning using a virtual three-dimensional model of the heart and may aid in the acquisition of the cognitive and technical skills needed to perform TTE. The ability to link probe manipulation, cardiac anatomy, and echocardiographic images using a simulator has been shown to be an effective model for training anesthesiology residents in transesophageal echocardiography. A proposed alternative to real-time reality patient-based learning is simulation-based training that allows anesthesiologists to learn complex concepts and procedures, especially for specific structures such as aortic valve. PMID:27397455

  16. The importance of echocardiography in diagnostics of idiopathic pulmonary arterial hypertension: A case report

    Directory of Open Access Journals (Sweden)

    Stojković Gabrijela

    2011-01-01

    Full Text Available Introduction. Idiopathic pulmonary arterial hypertension (IPAH is rare and difficult progressive disease with prevalence of approximately 15 cases per million residents, with predominant female cases. Case Outline. A 47-year-old female presented with symptoms and signs of the right heart chambers failure. Over prior seven years the patient had the feeling of suffocation and fatigue when walking, and received treatment for bronchial asthma. Physical examination revealed a marked loud second heart sound over the pulmonary artery. Electrocardiogram: right ventricular hypertrophy. Spirometric (pulmonary capacity test, cardiac perfusion scan and spiral CT scanning excluded secondary pulmonary arterial hypertension. Blood testing for connective tissue diseases and HIV were within normal reference limits. Transthoracic colour Doppler echocardiography demonstrated a mild tricuspid regurgitation with high values of estimated maximal and middle systolic pressure of the right ventricle (135/110 mm Hg, and excluded previous heart disease. Cardiac catheterization confirmed IPAH diagnosis, with systolic right ventricular pressure of 101/47/66 mm Hg and pulmonary capillary pressure of 30/13/10 mm Hg. Basic therapy with sildenafil, nevertheless, considerable limitations of strain tolerance was still present. Conclusion. IPAH is a severe heart disease with non-specific signs and symptoms. Screening for IPAH is transthoracic colour Doppler echocardiography shows high correlation with cardiac catheterization.

  17. Steerable Doppler transducer probes

    Energy Technology Data Exchange (ETDEWEB)

    Fidel, H.F.; Greenwood, D.L.

    1986-07-22

    An ultrasonic diagnostic probe is described which is capable of performing ultrasonic imaging and Doppler measurement consisting of: a hollow case having an acoustic window which passes ultrasonic energy and including chamber means for containing fluid located within the hollow case and adjacent to a portion of the acoustic window; imaging transducer means, located in the hollow case and outside the fluid chamber means, and oriented to direct ultrasonic energy through the acoustic window toward an area which is to be imaged; Doppler transducer means, located in the hollow case within the fluid chamber means, and movably oriented to direct Doppler signals through the acoustic window toward the imaged area; means located within the fluid chamber means and externally controlled for controllably moving the Doppler transducer means to select one of a plurality of axes in the imaged area along which the Doppler signals are to be directed; and means, located external to the fluid chamber means and responsive to the means for moving, for providing an indication signal for identifying the selected axis.

  18. Assessment of cardiac functions using tissue Doppler imaging in children with familial Mediterranean fever.

    Science.gov (United States)

    Ozdemir, Osman; Agras, Pinar Isik; Aydin, Yusuf; Abaci, Ayhan; Hizli, Samil; Akkus, Halil Ibrahim; Fidan, Cihan

    2012-04-01

    Familial Mediterranean fever may carry a potential for cardiovascular disorders because of sustained inflammation during its course; however, there has been a limited number of studies investigating the cardiac functions in children. The aim of this study was to assess both ventricular diastolic functions using conventional echocardiography and tissue Doppler imaging in children with familial Mediterranean fever. The study population included 25 patients with familial Mediterranean fever - mean age was 11.8 plus or minus 5.30 years - and 23 healthy patients as controls - mean age was 9.88 plus or minus 3.69 years. Both ventricular functions were measured using echocardiography comprising standard M-mode and conventional Doppler and tissue Doppler imaging during an attack-free period. The conventional echocardiographic parameters with myocardial performance index were in normal ranges and similar in patients with familial Mediterranean fever and controls, with a p-value more than 0.05. However, right ventricular diastolic dysfunction was observed in patients with familial Mediterranean fever documented by tissue Doppler imaging, with a p-value less than 0.05 for E't and A't wave ratio. Using tissue Doppler imaging, we have demonstrated that although left ventricular functions were comparable in the patients and healthy children, right ventricular diastolic function indices were impaired in patients with familial Mediterranean fever during childhood. Impaired right ventricular diastolic function may be an early manifestation of cardiac involvement in children with familial Mediterranean fever.

  19. Echocardiographic evaluation of external iliac artery Doppler waveform in patients with coronary artery disease.

    Science.gov (United States)

    Styczynski, Grzegorz; Szmigielski, Cezary; Kaczynska, Anna; Kuch-Wocial, Agnieszka

    2014-04-01

    Visual interpretation of the Doppler waveform in the common femoral or distal external iliac artery (EIA) was reported to be useful in screening for proximal peripheral artery occlusive disease (PAOD) in patients with lower limb ischemia. Commonly patients with coronary artery disease (CAD) referred for echocardiography have coexistent arterial pathology. Therefore, we decided to study whether echocardiographic evaluation of the distal EIA flow can be useful for detection of PAOD in patients with CAD. We studied 150 consecutive patients (pts) with CAD referred for echocardiography. At the end of an echocardiographic examination, evaluation of the flow in the distal EIA with an echocardiographic probe was performed. The Doppler waveform was classified as normal-with early diastolic flow reversal or abnormal-without early diastolic flow reversal. Echocardiographic findings were compared in a blinded fashion with the results of the ankle brachial index measurements (ABI). Based on the ABI ≤ 0.9, peripheral artery disease was diagnosed in 54 pts (36%) and abnormal external iliac Doppler waveform was found in 27 pts (18%). Sensitivity of abnormal external iliac Doppler waveform in predicting PAOD was 48%, specificity 99%, positive predictive value (PPV) 96%, and negative predictive value 77%. Peripheral arterial occlusive disease is common in patients with CAD referred for echocardiographic study. Echocardiographic assessment of distal EIA Doppler waveform has low sensitivity, but high specificity and high PPV in the diagnosis of peripheral arterial occlusive disease.

  20. Soluble Suppression of Tumorigenicity 2 and Echocardiography in Sepsis.

    Science.gov (United States)

    Yang, Hyun Suk; Hur, Mina; Kim, Hanah; Magrini, Laura; Marino, Rossella; Di Somma, Salvatore

    2016-11-01

    Soluble suppression of tumorigenicity 2 (sST2) has emerged as a biomarker of cardiac stretch or remodeling, and has demonstrated a role in acutely decompensated heart failure. However, its role in sepsis-induced cardiac dysfunction is still unknown. We explored whether sST2 serum concentration reflects either systolic or diastolic dysfunction as measured by Doppler echocardiography. In a total of 127 patients with sepsis, correlations between sST2 and blood pressure, left ventricular (LV) ejection fraction, LV diastolic filling (ratio of early transmitral flow velocity to early diastolic mitral annulus velocity), and resting pulmonary arterial pressure were evaluated. Correlations between sST2 and other sepsis biomarkers (high-sensitivity C-reactive protein [hs-CRP] and procalcitonin) were also examined. sST2 showed a moderate correlation with mean arterial pressure (r=-0.3499) but no correlation with LV ejection fraction, diastolic filling, or resting pulmonary hypertension. It showed moderate correlations with hs-CRP and procalcitonin (r=0.2608 and r=0.3829, respectively). sST2 might have a role as a biomarker of shock or inflammation, but it cannot reflect echocardiographic findings of LV ejection fraction or diastolic filling in sepsis.

  1. Tissue Doppler assessment of right ventricular function in female patients with limited form of systemic sclerosis

    Directory of Open Access Journals (Sweden)

    Ayman Ahmed Abdelaziz

    2013-09-01

    Conclusions: Patients with limited form of SSc present with pulsed-tissue Doppler imaging indices indicative of right ventricle dysfunction, which had significant correlations with disease duration. Tissue Doppler is a valuable non-invasive tool for detecting RV myocardial involvement in patients with limited SSc.

  2. Imaging in repaired tetralogy of Fallot with a focus on recent advances in echocardiography.

    Science.gov (United States)

    Larios, Guillermo; Friedberg, Mark K

    2017-09-01

    Imaging is essential for the management of adults with repaired tetralogy of Fallot (rToF). Echocardiography and cardiac magnetic resonance imaging are the central modalities to assess rToF. Here we review recent literature on imaging rToF, focusing on echocardiography and advances in assessment of cardiac mechanics. Several two-dimensional, three-dimensional, and Doppler echo parameters have been proposed to assess pulmonary regurgitation, right ventricular volumes and ejection fraction, but most of them still have important limitations in their feasibility and reliability compared to cardiac magnetic resonance (CMR). Myocardial deformation imaging to study ventricular and atrial mechanics, regional function, ventricular-ventricular interactions, and electro-mechanical dyssynchrony has yielded insights into the pathophysiologic mechanisms of right ventricular and left ventricular dysfunction; thereby predicting clinical outcomes and exercise capacity, allowing among others, evaluation of the impact of pulmonary valve replacement (PVR). Emerging technologies are expected to further our understanding of the drivers of dysfunction and guide indications and timing of PVR. Echocardiography and CMR have complementary and overlapping roles in rToF and contribute to our understanding of its pathophysiology and management.

  3. Progressive development of pulmonary hypertension leading to right ventricular hypertrophy assessed by echocardiography in rats.

    Science.gov (United States)

    Kato, Yosuke; Iwase, Mitsunori; Kanazawa, Hiroaki; Kawata, Natsuki; Yoshimori, Yukie; Hashimoto, Katsunori; Yokoi, Toyoharu; Noda, Akiko; Takagi, Kenzo; Koike, Yasuo; Nishizawa, Takao; Nishimura, Masahiko; Yokota, Mitsuhiro

    2003-07-01

    The present study aimed to evaluate the development of pulmonary hypertension by serial echocardiography, including measurements of pulmonary artery (PA) flow velocities, and correlate echocardiographic indices with pathological findings in rats administered monocrotaline (MCT). MCT (60 mg/kg body weight) or physiologic saline was administered to a total of 9 male Wistar rats at the age of 4 weeks (MCT group: n = 4, control group: n = 5, respectively). Echocardiography was performed serially until the age of 8 weeks. The ratio of right ventricular (RV) outflow tract dimensions to aortic dimensions increased progressively in the MCT group and became significantly greater than that of the control group after the age of 6 weeks. Peak PA velocity (Peak V) in the MCT group was significantly less than that of the control group at the ages of 7 and 8 weeks. The ratio of acceleration time to ejection time (AT/ET) in PA flow waveforms declined progressively and was significantly less than that of the control group after the age of 6 weeks. The ratio of RV weight to body weight (RVW/BW) in the MCT group was significantly greater than that of the control group. Both AT/ET ratio and Peak V were significantly inversely correlated with RVW/BW ratio. Furthermore, these echocardiographic findings were also significantly inversely correlated with the mean cross-sectional RV myocyte area. In conclusion, the progressive development of pulmonary hypertension leading to RV hypertrophy can be evaluated appropriately by echocardiography including PA flow Doppler indices in rats.

  4. Heartrate variation of umbilical artery Doppler waveforms.

    Science.gov (United States)

    Hoskins, P R; Johnstone, F D; Chambers, S E; Haddad, N G; White, G; McDicken, W N

    1989-01-01

    Umbilical artery Doppler waveforms from 20 patients were used to investigate the dependence of resistance index and pulsatility index on beat to beat pulse length over short time periods for individual patients, and on the usefulness of a common normalisation formula. For individual patients the resistance index and pulsatility index were only partially correlated with pulse length. Changes in both indices occurred independently of pulse length. Use of a common normalisation formula resulted in no significant reduction of the coefficient of variation of the resistance index (p greater than 0.1), and a reduction in the coefficient of variation of the pulsatility index of 10% (p greater than 0.001). It is concluded that short term changes in resistance index and pulsatility index cannot be corrected by a common normalisation formula.

  5. Improved cardiac motion detection from ultrasound images using TDIOF: a combined B-mode/ tissue Doppler approach

    Science.gov (United States)

    Tavakoli, Vahid; Stoddard, Marcus F.; Amini, Amir A.

    2013-03-01

    Quantitative motion analysis of echocardiographic images helps clinicians with the diagnosis and therapy of patients suffering from cardiac disease. Quantitative analysis is usually based on TDI (Tissue Doppler Imaging) or speckle tracking. These methods are based on two independent techniques - the Doppler Effect and image registration, respectively. In order to increase the accuracy of the speckle tracking technique and cope with the angle dependency of TDI, herein, a combined approach dubbed TDIOF (Tissue Doppler Imaging Optical Flow) is proposed. TDIOF is formulated based on the combination of B-mode and Doppler energy terms in an optical flow framework and minimized using algebraic equations. In this paper, we report on validations with simulated, physical cardiac phantom, and in-vivo patient data. It is shown that the additional Doppler term is able to increase the accuracy of speckle tracking, the basis for several commercially available echocardiography analysis techniques.

  6. Doppler cooling a microsphere

    CERN Document Server

    Barker, P F

    2010-01-01

    Doppler cooling the center-of-mass motion of an optically levitated microsphere via the velocity dependent scattering force from narrow whispering gallery mode (WGM) resonances is described. Light that is red detuned from the WGM resonance can be used to damp the center-of-mass motion in a process analogous to the Doppler cooling of atoms. Leakage of photons out of the microsphere when the incident field is near resonant with the narrow WGM resonance acts to damp the motion of the sphere. The scattering force is not limited by saturation, but can be controlled by the incident power. Cooling times on the order of seconds are calculated for a 20 micron diameter silica microsphere trapped within optical tweezers, with a Doppler temperature limit in the microKelvin regime.

  7. Combined perfusion and doppler imaging using plane-wave nonlinear detection and microbubble contrast agents.

    Science.gov (United States)

    Tremblay-Darveau, Charles; Williams, Ross; Milot, Laurent; Bruce, Matthew; Burns, Peter N

    2014-12-01

    Plane-wave imaging offers image acquisition rates at the pulse repetition frequency, effectively increasing the imaging frame rates by up to two orders of magnitude over conventional line-by-line imaging. This form of acquisition can be used to achieve very long ensemble lengths in nonlinear modes such as pulse inversion Doppler, which enables new imaging trade-offs that were previously unattainable. We first demonstrate in this paper that the coherence of microbubble signals under repeated exposure to acoustic pulses of low mechanical index can be as high as 204 ± 5 pulses, which is long enough to allow an accurate power Doppler measurement. We then show that external factors, such as tissue acceleration, restrict the detection of perfusion at the capillary level with linear Doppler, even if long Doppler ensembles are considered. Hence, perfusion at the capillary level can only be detected with ultrasound through combined microbubbles and Doppler imaging. Finally, plane-wave contrast-enhanced power and color Doppler are performed on a rabbit kidney in vivo as a proof of principle. We establish that long pulse-inversion Doppler sequences and conventional wall-filters can create an image that simultaneously resolves both the vascular morphology of veins and arteries, and perfusion at the capillary level with frame rates above 100 Hz.

  8. Comparison of magnetic resonance imaging and echocardiography in determination of cardiac dimensions in normal subjects.

    Science.gov (United States)

    Friedman, B J; Waters, J; Kwan, O L; DeMaria, A N

    1985-06-01

    No data exist regarding the ability of magnetic resonance imaging to assess cardiac size and performance in human beings. Therefore, measurements of cardiac dimensions by magnetic resonance imaging were compared with those obtained by two-dimensional echocardiography in 21 normal subjects. Magnetic resonance transverse cardiac sections were obtained during electrocardiographic gating using a spin echo pulse sequence. In normal subjects, magnetic resonance imaging yielded a range of values for cardiac dimensions having a similar standard deviation as that of two-dimensional echocardiography. Diastolic measurements of the aorta, left atrium, left ventricle and septum obtained by magnetic resonance imaging correlated well with those obtained by two-dimensional echocardiography (r = 0.82, 0.78, 0.81 and 0.75, respectively). The correlation coefficient of r = 0.35 observed for the posterior wall thickness was not surprising in view of the narrow range of normal values. Only a general correlation (r = 0.53) existed for the right ventricular diastolic dimension; this was probably related to the difficulty in obtaining representative measurements due to the complex geometry of this chamber. Failure of systolic dimension measurements by magnetic resonance imaging to correlate with those obtained by echocardiography is probably related to limitations of electrocardiographic gating, especially of determining the exact end-systolic frame. Although technically complex at present, magnetic resonance imaging does provide an additional noninvasive technique for measurement of cardiac size.

  9. [Color-Doppler semiology in transplanted kidney].

    Science.gov (United States)

    Rivolta, R; Castagnone, D; Burdick, L; Mandelli, C; Mangiarotti, R

    1993-05-01

    Color-encoded duplex ultrasonography (CEDU) makes a more accurate technique in kidney graft monitoring by combining real-time US with pulsed Doppler studies of renal vasculature. It is a non-invasive and easy technique. Suitable to study the whole renal artery and vein, CEDU also allows the qualitative and quantitative assessment of the intrarenal vasculature and therefore the easy diagnosis of such vessel dysfunctions as arteriovenous fistulas following biopsy. Moreover, Doppler spectral analysis can be used to distinguish among different causes of renal allograft dysfunction--i.e. rejection, cyclosporine nephrotoxicity or acute tubular necrosis. The value of the resistive index for the differential diagnosis is discussed. CEDU allows a more reliable measurement of renal blood flow thanks to the more precise evaluation of renal artery diameter and mean flow velocity.

  10. Doppler radar physiological sensing

    CERN Document Server

    Lubecke, Victor M; Droitcour, Amy D; Park, Byung-Kwon; Singh, Aditya

    2016-01-01

    Presents a comprehensive description of the theory and practical implementation of Doppler radar-based physiological monitoring. This book includes an overview of current physiological monitoring techniques and explains the fundamental technology used in remote non-contact monitoring methods. Basic radio wave propagation and radar principles are introduced along with the fundamentals of physiological motion and measurement. Specific design and implementation considerations for physiological monitoring radar systems are then discussed in detail. The authors address current research and commercial development of Doppler radar based physiological monitoring for healthcare and other applications.

  11. Assessment of left ventricular regional function in affected and carrier dogs with duchenne muscular dystrophy using speckle tracking echocardiography

    Directory of Open Access Journals (Sweden)

    Yugeta Naoko

    2011-05-01

    Full Text Available Abstract Background Two-dimensional speckle tracking echocardiography (STE is a relatively new method to detect regional myocardial dysfunction. To assess left ventricular (LV regional myocardial dysfunction using STE in Duchenne muscular dystrophy model dogs (CXMDJ without overt clinical signs of heart failure. Methods Six affected dogs, 8 carrier dogs with CXMDJ, and 8 control dogs were used. Conventional echocardiography, systolic and diastolic function by Doppler echocardiography, tissue Doppler imaging (TDI, and strain indices using STE, were assessed and compared among the 3 groups. Results Significant differences were seen in body weight, transmitral E wave and E' wave derived from TDI among the 3 groups. Although no significant difference was observed in any global strain indices, in segmental analysis, the peak radial strain rate during early diastole in posterior segment at chordae the tendineae level showed significant differences among the 3 groups. Conclusions The myocardial strain rate by STE served to detect the impaired cardiac diastolic function in CXMDJ without any obvious LV dilation or clinical signs. The radial strain rate may be a useful parameter to detect early myocardial impairment in CXMDJ.

  12. Automated analysis of 3D echocardiography

    NARCIS (Netherlands)

    Stralen, Marijn van

    2009-01-01

    In this thesis we aim at automating the analysis of 3D echocardiography, mainly targeting the functional analysis of the left ventricle. Manual analysis of these data is cumbersome, time-consuming and is associated with inter-observer and inter-institutional variability. Methods for reconstruction o

  13. Dynamic 3D echocardiography in virtual reality.

    NARCIS (Netherlands)

    A.E. van den Bosch (Annemien); A.H.J. Koning (Anton); F.J. Meijboom (Folkert); J.S. McGhie (Jackie); M.L. Simoons (Maarten); P.J. van der Spek (Peter); A.J.J.C. Bogers (Ad)

    2005-01-01

    textabstractBACKGROUND: This pilot study was performed to evaluate whether virtual reality is applicable for three-dimensional echocardiography and if three-dimensional echocardiographic 'holograms' have the potential to become a clinically useful tool. METHODS: Three-dimensional echocardiographic d

  14. The reference values and Z scores regression equations of normal newborns undergoing echocardiography%新生儿超声心动图正常参考值及Z值回归方程式的研究

    Institute of Scientific and Technical Information of China (English)

    林洲; 谢燕华; 夏焙; 许娜; 李姝娜; 何学智; 王娟; 刘磊; 欧福祥; 陈伟玲

    2014-01-01

    Objective To investigate the reference values and Z scores regression equations of newborn undergoing echocardiography. Methods Two hundred and eighty-eight newborns (aged 0-28 days) of Shenzhen Children′s Hospital underwent echocardiography examination, including M-mode, two-dimensional (2D) and real-time three-dimensional (3D) echocardiography, color Doppler lfow imaging (CDFI) and tissue Doppler imaging. The correlation between echocardiography results and weight were analyzed and Z scores were calculated. Results The normal values of right ventricular diameter (RV) and left ventricular end-diastolic diameter (LVEDD) measured by M-mode, the mitral annulus diameter in four chamber view (MV-D1), mitral annulus diameter in two chamber view (MV-D2), mitral annulus diameter in longitudinal view (MV-D3), aortic ring diameter (ARD), aortic sinus diameter (ASD), ascending aorta diameter (AAO), transverse aorta diameter (TA), aortic isthmus diameter (AI), aorta diaphragm diameter (AO-Dia), tricuspid annulus diameter in four chamber view (TV-D1), tricuspid annulus diameter in right ventricular inlfow tract view (TV-D2), right ventricular outlfow tract diameter (RVOT), pulmonary valve diameter (PVD) and main pulmonary artery diameter (PA) measured by 2D echocardiography and the normal values of mitral valve inflow Doppler component during early diastole (MV-E), mitral valve inlfow Doppler component during atrial contraction (MV-A), tricuspid valve inlfow Doppler component during early diastole (TV-E), tricuspid valve inflow Doppler component during atrial contraction (TV-A), aortic valve peak velocity (AV-max), aortic valve velocity-time integral (AV-VTI), pulmonary valve peak velocity (PV-max), pulmonary valve velocity-time integral (PV-VTI) measured by pulse Doppler, the mitral annular tissue Doppler component during systole (MV-s′), mitral annular tissue Doppler component during early diastole (MV-e′), mitral annular tissue Doppler component during atrial

  15. Recent advances in echocardiography for valvular heart disease.

    Science.gov (United States)

    Hahn, Rebecca

    2015-01-01

    Echocardiography is the imaging modality of choice for the assessment of patients with valvular heart disease. Echocardiographic advancements may have particular impact on the assessment and management of patients with valvular heart disease. This review will summarize the current literature on advancements, such as three-dimensional echocardiography, strain imaging, intracardiac echocardiography, and fusion imaging, in this patient population.

  16. suPAR level is associated with myocardial impairment assessed with advanced echocardiography in patients with type 1 diabetes with normal ejection fraction and without known heart disease or end-stage renal disease

    DEFF Research Database (Denmark)

    Theilade, Simone; Rossing, Peter; Eugen-Olsen, Jesper

    2016-01-01

    Doppler and speckle tracking echocardiography, and measured plasma suPAR levels. Associations between myocardial function and suPAR levels were studied in adjusted models including significant covariates. RESULTS: Patients were 55±12 years (mean±s.d.) and 160 (50%) males. Median (interquartile range) su...

  17. Direct visualization of a significant stenosis of the right coronary artery by transthoracic echocardiography. A case report

    Directory of Open Access Journals (Sweden)

    Wiseth Rune

    2007-10-01

    Full Text Available Abstract Non-invasive imaging of coronary arteries by transthoracic echocardiography is an emerging diagnostic tool to study the left main (LM, left descending artery (LAD, circumflex (Cx and right coronary artery (RCA. Impaired coronary circulation can be assessed by measuring coronary velocity flow reserve (CVFR by transthoracic Doppler echocardiography. Coronary artery stenoses can be identified as localized colour aliasing and accelerated flow velocities. We report a case with an acute coronary syndrome (ACS of a 46-year-old man. With non-invasive imaging of coronary arteries by transthoracic echocardiography (TTE, we identified a segment of the mid right coronary artery (RCA suggestive of stenosis with localized colour aliasing and accelerated flow velocity. We found a high ratio between the stenotic peak velocity and the prestenotic peak velocity, and a pathologic coronary flow velocity reserve (CFVR distal to the stenosis in the posterior interventricular descending branch (RDP. Subsequent coronary angiography demonstrated one vessel disease with a stenosis in segment 3 of RCA, which was successfully treated with percutaneos coronary intervention PCI. Two weeks following the PCI procedure he was readmitted to hospital with chest pain. A subacute stent thrombosis was questioned, and repeated echocardiography was preformed. The mid portion of RCA showed normal and laminar flow. The CVFR of RCA measured in the RDP showed normal vasodilatory response, confirming an open RCA without any flow limitation. A repeated coronary angiogram demonstrated only a mild in stent intimal hyperplasia. This case illustrates the value of transthoracic echocardiography as a tool both in the diagnosis and the follow-up of chest pain disorders and coronary flow problems. Transthoracic echocardiography allows both direct visualization of the various coronary segments and assessment of the CVFR.

  18. Dobutamine stress echocardiography: a review and update

    Directory of Open Access Journals (Sweden)

    Gilstrap LG

    2014-04-01

    Full Text Available Lauren Gray Gilstrap,1 R Sacha Bhatia,2 Rory B Weiner,3 David M Dudzinski3 1Division of Cardiology, Brigham and Women's Hospital, Boston, MA, USA; 2Institute for Health Systems Solutions, Women's College Hospital, Toronto, ON, Canada; 3Cardiology Division, Massachusetts General Hospital, Boston, MA, USA Abstract: Stress echocardiography is a noninvasive cardiovascular diagnostic test that provides functional and hemodynamic information in the assessment of a number of cardiac diseases. Performing stress echocardiography with a pharmacologic agent such as dobutamine allows for simulation of increased heart rate and increased myocardial physiologic demands in patients who may be unable to exercise due to musculoskeletal or pulmonary comorbidities. Dobutamine stress echocardiography (DSE, like exercise echocardiography, has found its primary application in ischemic heart disease, with roles in identification of obstructive epicardial coronary artery disease, detection of viable myocardium, and assessment of the efficacy of anti-ischemic medical therapy in patients with known coronary artery disease. DSE features prominently in the evaluation and management of valvular heart disease by helping to assess the effects of mitral and aortic stenoses, as well as a specific use in differentiating true severe valvular aortic stenosis from pseudostenosis that may occur in the setting of left ventricular systolic dysfunction. DSE is generally well tolerated, and its side effects and contraindications generally relate to consequences of excess inotropic and/or chronotropic stimulation of the heart. The aim of this paper is to review the indications, contraindications, advantages, disadvantages, and risks of DSE. Keywords: stress echocardiography, dobutamine, coronary artery disease, myocardial ischemia

  19. Speckle Tracking Imaging in Normal Stress Echocardiography.

    Science.gov (United States)

    Leitman, Marina; Tyomkin, Vladimir; Peleg, Eli; Zyssman, Izhak; Rosenblatt, Simcha; Sucher, Edgar; Gercenshtein, Vered; Vered, Zvi

    2017-04-01

    Exercise stress echocardiography is a widely used modality for the diagnosis and follow-up of patients with coronary artery disease. During the last decade, speckle tracking imaging has been used increasingly for accurate evaluation of cardiac function. This work aimed to assess speckle-tracking imaging parameters during nonischemic exercise stress echocardiography. During 2011 to 2014 we studied 46 patients without history of coronary artery disease, who completed exercise stress echocardiography protocol, had normal left ventricular function, a nonischemic response, and satisfactory image quality. These exams were analyzed with speckle-tracking imaging software at rest and at peak exercise. Peak strain and time-to-peak strain were measured at rest and after exercise. Clinical follow-up included a telephone contact 1 to 3 years after stress echo exam, confirming freedom from coronary events during this time. Global and regional peak strain increased following exercise. Time-to-peak global and regional strain and time-to-peak strain adjusted to the heart rate were significantly shorter in all segments after exercise. Rest-to-stress ratio of time-to-peak strain adjusted to the heart rate was 2.0 to 2.8. Global and regional peak strain rise during normal exercise echocardiography. Peak global and regional strain occur before or shortly after aortic valve closure at rest and after exercise, and the delay is more apparent at the basal segments. Time-to-peak strain normally shortens significantly during exercise; after adjustment to heart rate it shortens by a ratio of 2.0 to 2.8. These data may be useful for interpretation of future exercise stress speckle-tracking echocardiography studies. © 2016 by the American Institute of Ultrasound in Medicine.

  20. High-resolution kinetic energy distributions via doppler shift measurements

    Science.gov (United States)

    Xu, Z.; Koplitz, B.; Buelow, S.; Baugh, D.; Wittig, C.

    1986-07-01

    In photolysis/probe experiments using pulsed sources, time delay produces both spatial and directional bias in the fragment distributions, thus enabling well-resolved kinetic energy distributions to be obtained from Doppler shift measurements. Data are presented for H-atoms detected using two-photon ionization, and high S/N and laser-limited kinetic energy resolution are demonstrated.

  1. Study of an airborne Doppler radar: Project Asterix

    Science.gov (United States)

    Testud, Jacques; Baudin, F.; Amayenc, P.

    Specifications for an airborne Doppler radar for meteorological applications are given. The following areas are covered: (1) principle for measuring three-dimensional speed field; (2) pulse pattern and detectability; (3) antenna; (4) processing of data; (5) analog system; (6) data control and recording; (7) attitude control and vibrations; and (8) logistics.

  2. UTEROPLACENTAL DOPPLER VELOCIMETRY DURING BRAXTON-HICKS CONTRACTIONS

    NARCIS (Netherlands)

    DIJKSTRA, K; AARNOUDSE, JG; Oosterhof, H.

    1992-01-01

    Pulsed-wave Doppler ultrasound was used to evaluate the influence of Braxton Hicks' contractions on flow velocity waveforms in the uterine arteries. Flow velocity waveforms were obtained from a standardized site, at the crossing of the uterine artery with the external iliac artery near the uterine w

  3. Unidirectional Rotation of Molecules Measured by the Rotational Doppler Effect

    Directory of Open Access Journals (Sweden)

    Prior Yehiam

    2013-03-01

    Full Text Available A pair of linearly polarized pump pulses induce field-free unidirectional molecular rotation, which is detected by a delayed circularly polarized probe. The polarization and spectrum of the probe are modified by the interaction with the molecules, in accordance with the Rotational Doppler Effect.

  4. Scanning laser Doppler vibrometry

    DEFF Research Database (Denmark)

    Brøns, Marie; Thomsen, Jon Juel

    With a Scanning Laser Doppler Vibrometer (SLDV) a vibrating surface is automatically scanned over predefined grid points, and data processed for displaying vibration properties like mode shapes, natural frequencies, damping ratios, and operational deflection shapes. Our SLDV – a PSV-500H from...

  5. The Doppler Pendulum Experiment

    Science.gov (United States)

    Lee, C. K.; Wong, H. K.

    2011-01-01

    An experiment to verify the Doppler effect of sound waves is described. An ultrasonic source is mounted at the end of a simple pendulum. As the pendulum swings, the rapid change of frequency can be recorded by a stationary receiver using a simple frequency-to-voltage converter. The experimental results are in close agreement with the Doppler…

  6. Isoproterenol Stress Echocardiography in Assessing Mitral Valve Area Reserve before and after Percutaneous Balloon Valvuloplasty

    Institute of Scientific and Technical Information of China (English)

    刘品明; 傅向阳; 吕俊豪; 吴群; 杨福庆

    2001-01-01

    Objective To determine whether successful valvuloplasty causes an increase of mitral valve area reserve in patients with mitral stenosis, isoproterenol stress echocardiography was used to compare mitral valve area and hemodynamic changes between pre- and post- valvuloplasty under conditions of increased cardiac work. Methods Thirtyeight patients with pure rheumatic mitral stenosis who had received successful percutaneous balloon valvulo plasty underwent isoproterenol stress echocardiography pre- and post- valvuloplasty. Mitral valve area (by direct planimetry of two- dimensional echocardiography), mean transmitral pressure gradient (by continuous-wave Doppler echocardiography), and cardiac output (by M -mode echocardiography) were measured at rest and under isoproterenol stress to achieve heart rate of different stages. Results Mitral valve area (0. 91± 0. 28 to 1. 87±0.23cm2, P <0.01), mean transmitral pressure gradient ( 12.5 ± 6. 3 to 3.9 ± 1.9mmHg, P < 0.01 ) and cardiac output (3.93 ± 1.44to 4. 73 ± 1.01 L/min, P < 0.05) at rest between pre - and post -valvuloplasty were significantly different.Pre-valvuloplasty, as heart rate increased under stress, mean transmitral pressure gradient increased significantly ( P < 0.01 ), but there were no significant differences in the measurements of mitral valve area and cardiac output (both P > 0.05). In contrast, as heart rate increased post- valvuloplasty, there was a significant increase in mean transmitral pressure gradient (P < 0.01), but both mitral valve area and cardiac output further increased significantly (both P < 0. 01) . Moreover, valvuloplasty decreased mean transmitral pressure gradient at peak heart rate from 23.0 ± 4. 5 to 7.75 ± 2.30 mmHg ( P < 0.01 ) under submaximal stress. Conclusions Successful percu taneous balloon valvuloplasty soon causes a significant increase of mitral valve area reserve in patients with mitral stenosis, which is markedly manifested under conditions of

  7. Doppler ultrasonography of the lower extremity arteries: anatomy and scanning guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Ji Young [Dept. of Radiology, Ewha Womans University School of Medicine, Seoul (Korea, Republic of)

    2017-04-15

    Doppler ultrasonography of the lower extremity arteries is a valuable technique, although it is less frequently indicated for peripheral arterial disease than for deep vein thrombosis or varicose veins. Ultrasonography can diagnose stenosis through the direct visualization of plaques and through the analysis of the Doppler waveforms in stenotic and poststenotic arteries. To perform Doppler ultrasonography of the lower extremity arteries, the operator should be familiar with the arterial anatomy of the lower extremities, basic scanning techniques, and the parameters used in color and pulsed-wave Doppler ultrasonography.

  8. Ligation or distortion of the right circumflex artery during minimal invasive mitral valve repair detected by transesophageal echocardiography.

    Science.gov (United States)

    Ender, Joerg; Gummert, Jan; Fassl, Jens; Krohmer, Eugen; Bossert, Thorsten; Mohr, Friedrich W

    2008-04-01

    A 43-year-old male patient undergoing mitral valve repair because of severe mitral regurgitation as a result of P2 prolapse was treated with insertion of neochords and a 36 Carpentier-Edwards physio-ring. After weaning from cardiopulmonary bypass, S-T elevation in leads II, III, and aVF occurred. On transesophageal echocardiography an occlusion or distortion of the circumflex artery by ring sutures was suggested, because coronary flow was no longer detected by color Doppler. Despite stable hemodynamics an angiogram was performed, which confirmed the diagnosis of stenosis of the circumflex artery. During reoperation 4 sutures placed at the P1 segment of the mitral valve annuloplasty were corrected. Transesophageal echocardiography could detect a good flow of the circumflex artery and the electrocardiographic changes disappeared.

  9. 双多普勒超声评估胎儿房性期前收缩%Dual Doppler ultrasonography in the evaluation of fetal atrial extrasystoles

    Institute of Scientific and Technical Information of China (English)

    陈秋月; 吕国荣; 刘婧

    2013-01-01

    目的 探讨双多普勒超声在检测胎儿房性期前收缩中的应用价值.方法 应用彩色多普勒超声对7013例胎儿进行常规检查,发现有胎儿心律失常者行双多普勒超声检查,同步记录肝静脉(HV)、降主动脉(DAo)血流频谱.比较20例正常心律胎儿常规多普勒及双多普勒检测时间.结果 检出房性期前收缩胎儿28例,包括房性期前收缩伴下传14例,房性期前收缩伴未下传8例,房性期前收缩部分下传部分未下传6例,所有病例未发现合并严重先天性心脏畸形.26例房性期前收缩胎儿均于晚孕期转为正常窦性心律,2例胎儿于产后3d转为正常窦性心律.正常胎儿的心律双多普勒超声检测时间明显少于常规多普勒(P<0.05).结论 双多普勒超声检测胎儿房性期前收缩简便、快速,可用于精确诊断胎儿房性期前收缩.%Objective To evaluate the value of dual Doppler ultrasonography in the diagnosis of fetal atrial extrasystoles.Methods Seven thousands and thirteen fetuses were examined by fetal echocardiography.If fetal arrhythmias were found,information of pulsed wave Doppler signals in hepatic vein (HV) and descending aorta (DAo) using dual Doppler were colleted simultaneously.The detected times were compared between using general Doppler and dual Doppler in 20 cases.Results On dual Doppler examination,28 of the fetuses showed signals of atrial extrasystoles,14 fetuses atrial extrasystoles conducted to ventricle,8 fetuses atrial extrasystoles non-conducted to ventricle,6 fetuses with part of the extrasystoles conducted to ventricle and part of the extrasystoles non-conducted to ventricle.No case had congenital heart disease.Twenty-six fetuses with atrial extrasystole were converted to normal rhythm within the third trimester of pregnancy,and the others' were converted to normal rhythm during the first 3 days postnatally.The detected time of dual Doppler was shorter than that of general Doppler(P <0

  10. Artifacts in three-dimensional transesophageal echocardiography.

    Science.gov (United States)

    Faletra, Francesco Fulvio; Ramamurthi, Alamelu; Dequarti, Maria Cristina; Leo, Laura Anna; Moccetti, Tiziano; Pandian, Natesa

    2014-05-01

    Three-dimensional (3D) transesophageal echocardiography (TEE) is subject to the same types of artifacts encountered on two-dimensional TEE. However, when displayed in a 3D format, some of the artifacts appear more "realistic," whereas others are unique to image acquisition and postprocessing. Three-dimensional TEE is increasingly used in the setting of percutaneous catheter-based interventions and ablation procedures, and 3D artifacts caused by the metallic components of catheters and devices are particularly frequent. Knowledge of these artifacts is of paramount relevance to avoid misinterpretation of 3D images. Although artifacts and pitfalls on two-dimensional echocardiography are well described and classified, a systematic description of artifacts in 3D transesophageal echocardiographic images and how they affect 3D imaging is still absent. The aim of this review is to describe the most relevant artifacts on 3D TEE, with particular emphasis on those occurring during percutaneous interventions for structural heart disease and ablation procedures.

  11. Exercise echocardiography for structural heart disease.

    Science.gov (United States)

    Izumo, Masaki; Akashi, Yoshihiro J

    2016-03-01

    Since the introduction of transcatheter structural heart intervention, the term "structural heart disease" has been widely used in the field of cardiology. Structural heart disease refers to congenital heart disease, valvular heart disease, and cardiomyopathy. In structural heart disease, valvular heart disease is frequently identified in the elderly. Of note, the number of patients who suffer from aortic stenosis (AS) and mitral regurgitation (MR) is increasing in developed countries because of the aging of the populations. Transcatheter aortic valve replacement and percutaneous mitral valve repair has been widely used for AS and MR, individually. Echocardiography is the gold standard modality for initial diagnosis and subsequent evaluation of AS and MR, although the difficulties in assessing patients with these diseases still remain. Here, we review the clinical usefulness and prognostic impact of exercise echocardiography on structural heart disease, particularly on AS and MR.

  12. Application of Contrast Echocardiography in Invasive Cardiology

    Directory of Open Access Journals (Sweden)

    Mustafa Bulut

    2010-12-01

    Full Text Available Contrast echocardiography by rendering better imaging of the borders of cardiac chambers is a useful tool for evaluating cardiac function, mass, myocardial vascularization, microvascular structure (small vessel vasculature and viability. Contrast was first started to be used for patients with suboptimal image quality. It can be used in detecting defects in myocardial blood supply in patients with chest pain and determining the success of interventionalprocedures. It can also be of help in demonstrating myocardial viability after reperfusion treatment in patients who had myocardial infarction. It is expected to be used more widely in invasive cardiology for decision making, guiding and determining the success of the procedures. Advances in imaging techniques , development of contrast materials for evaluation of left system, contrast echocardiography may become a routine clinical practice.

  13. Simulation-based training in echocardiography.

    Science.gov (United States)

    Biswas, Monodeep; Patel, Rajendrakumar; German, Charles; Kharod, Anant; Mohamed, Ahmed; Dod, Harvinder S; Kapoor, Poonam Malhotra; Nanda, Navin C

    2016-10-01

    The knowledge gained from echocardiography is paramount for the clinician in diagnosing, interpreting, and treating various forms of disease. While cardiologists traditionally have undergone training in this imaging modality during their fellowship, many other specialties are beginning to show interest as well, including intensive care, anesthesia, and primary care trainees, in both transesophageal and transthoracic echocardiography. Advances in technology have led to the development of simulation programs accessible to trainees to help gain proficiency in the nuances of obtaining quality images, in a low stress, pressure free environment, often with a functioning ultrasound probe and mannequin that can mimic many of the pathologies seen in living patients. Although there are various training simulation programs each with their own benefits and drawbacks, it is clear that these programs are a powerful tool in educating the trainee and likely will lead to improved patient outcomes. © 2016, Wiley Periodicals, Inc.

  14. Echocardiography diagnosis of myocardial infarction complications

    Directory of Open Access Journals (Sweden)

    N.D. Oryshchyn

    2016-03-01

    Full Text Available Diagnosis and management of myocardial infarction complications are discussed in this article. These complications are associated with high level of mortality and surgery is a main treatment method. High level of suspicion and early diagnosis are essential for appropriate treatment and improvement of prognosis. Echocardiography is a main diagnostic method. Analysis of literature about contemporary management of mechanical complications of myocardial infarction has been performed, case reports are presented.

  15. Application of Contrast Echocardiography in Invasive Cardiology

    OpenAIRE

    2010-01-01

    Contrast echocardiography by rendering better imaging of the borders of cardiac chambers is a useful tool for evaluating cardiac function, mass, myocardial vascularization, microvascular structure (small vessel vasculature) and viability. Contrast was first started to be used for patients with suboptimal image quality. It can be used in detecting defects in myocardial blood supply in patients with chest pain and determining the success of interventionalprocedures. It can also be of help in de...

  16. Dobutamine stress echocardiography: a review and update

    OpenAIRE

    Gilstrap LG; Bhatia RS; Weiner RB; Dudzinski DM

    2014-01-01

    Lauren Gray Gilstrap,1 R Sacha Bhatia,2 Rory B Weiner,3 David M Dudzinski3 1Division of Cardiology, Brigham and Women's Hospital, Boston, MA, USA; 2Institute for Health Systems Solutions, Women's College Hospital, Toronto, ON, Canada; 3Cardiology Division, Massachusetts General Hospital, Boston, MA, USA Abstract: Stress echocardiography is a noninvasive cardiovascular diagnostic test that provides functional and hemodynamic information in the assessment of a number of cardiac...

  17. Usefulness of coronary flow reserve over regional wall motion when added to dual-imaging dipyridamole echocardiography.

    Science.gov (United States)

    Rigo, Fausto; Richieri, Margherita; Pasanisi, Emilio; Cutaia, Valeria; Zanella, Carlo; Della Valentina, Patrizia; Di Pede, Francesco; Raviele, Antonio; Picano, Eugenio

    2003-02-01

    Vasodilator stress echocardiography allows semi-simultaneous imaging of left anterior descending (LAD) coronary flow and regional wall function. To assess the relative (and additive?) value of regional flow and function for noninvasive identification of angiographically assessed LAD disease in patients with chest pain syndrome, we studied 230 consecutive in-hospital patients (134 men, aged 63.5 +/- 11 years) with chest pain syndrome and normal regional and global left ventricular function. All patients underwent stress echocardiography with dipyridamole (up to 0.84 mg/kg over 10 minutes), including wall motion analysis by 2-dimensional echocardiography and coronary flow reserve (CFR) evaluation of the LAD artery by Doppler, with or without contrast injection. A new regional wall motion abnormality in >or=2 contiguous segments was required for 2-dimensional echocardiographic positivity. CFR was evaluated as the ratio of dipyridamole to peak diastolic coronary blood flow velocity at rest. All patients underwent coronary angiography within 60 days; a quantitatively assessed diameter reduction >50% of the LAD artery was considered significant. Of the 230 patients, 70 had LAD disease. A regional wall motion abnormality in LAD territory was present in 52 patients, and reduced CFR (<1.9) in 62 patients. Sensitivity for detecting LAD disease was 74% for 2-dimensional echocardiography (95% confidence interval [CI] 64% to 84%) and 81% for CFR <1.9 (95% CI 72% to 90%); specificity was 91% (95% CI 87% to 96%) for 2-dimensional echocardiography and 84% for CFR (95% CI 79% to 90%). Accuracy was 86% for 2-dimensional echocardiography (95% CI 82% to 91%) and 83.5% for CFR (95% CI 79% to 88%). When 2-dimensional echocardiography and CFR criteria were considered, sensitivity increased to 93% (95% CI 87% to 99%), with 80.6% specificity (95% CI 74.5% to 86.7%). CFR was assessed during vasodilator stress echocardiography. Its diagnostic accuracy for detecting LAD disease was comparable

  18. Pulse on Pulse

    DEFF Research Database (Denmark)

    Schmidt, Ulrik; Carlson, Merete

    2012-01-01

    Pulse on Pulse” investigates the relation between signifying processes and non-signifying material dynamism in the installation Pulse Room (2006-) by Mexican Canadian artist Rafael Lozano-Hemmer. In Pulse Room the sense of pulse is ambiguous. Biorhythms are transmitted from the pulsing energy...... and pulsating ‘room’. Hence, the visitors in Pulse Room are invited into a complex scenario that continuously oscillates between various aspects of signification (the light bulbs representing individual lives; the pulse itself as the symbolic ‘rhythm of life’) and instants of pure material processuality...... a multilayered sense of time and space that is central to the sensory experience of Pulse Room as a whole. Pulse Room is, at the very same time, an anthropomorfized archive of a past intimacy and an all-encompassing immersive environment modulating continuously in real space-time....

  19. Laser Doppler flowmetry imaging

    Science.gov (United States)

    Nilsson, Gert E.; Wardell, Karin

    1994-02-01

    A laser Doppler perfusion imager has been developed that makes possible mapping of tissue blood flow over surfaces with extensions up to about 12 cm X 12 cm. The He-Ne laser beam scans the tissue under study throughout 4096 measurement sites. A fraction of the backscattered and Doppler broadened light is detected by a photo diode positioned about 20 cm above the tissue surface. After processing, a signal that scales linearly with perfusion is stored in a computer and a color coded image of the spatial tissue perfusion is shown on a monitor. A full format scan is completed in about 4.5 minutes. Algorithms for calculating perfusion profiles and averages as well as substraction of one image from another, form an integral part of the system data analysis software. The perfusion images can also be exported to other software packages for further processing and analysis.

  20. Scanning laser Doppler vibrometry

    OpenAIRE

    2016-01-01

    With a Scanning Laser Doppler Vibrometer (SLDV) a vibrating surface is automatically scanned over predefined grid points, and data processed for displaying vibration properties like mode shapes, natural frequencies, damping ratios, and operational deflection shapes. Our SLDV – a PSV-500H from Polytec Inc. – was acquired and put to operation in October 2014, paid by a sub-donation of DKK 1,5 mill. of the total VILLUM CASMaT grant. Opening possibilities of measuring complicated vibration shapes...

  1. Holographic laser Doppler ophthalmoscopy

    CERN Document Server

    Simonutti, Manuel; Sahel, J A; Gross, Michel; Samson, Benjamin; Magnain, Caroline; Atlan, Michael; 10.1364/OL.35.001941

    2010-01-01

    We report laser Doppler ophthalmoscopic fundus imaging in the rat eye with near-IR heterodyne holography. Sequential sampling of the beat of the reflected radiation against a frequency-shifted optical local oscillator is made onto an array detector. Wide-field maps of fluctuation spectra in the 10 Hz to 25 kHz band exhibit angiographic contrasts in the retinal vascular tree without requirement of an exogenous marker.

  2. Laser double Doppler flowmeter

    Science.gov (United States)

    Poffo, L.; Goujon, J.-M.; Le Page, R.; Lemaitre, J.; Guendouz, M.; Lorrain, N.; Bosc, D.

    2014-05-01

    The Laser Doppler flowmetry (LDF) is a non-invasive method for estimating the tissular blood flow and speed at a microscopic scale (microcirculation). It is used for medical research as well as for the diagnosis of diseases related to circulatory system tissues and organs including the issues of microvascular flow (perfusion). It is based on the Doppler effect, created by the interaction between the laser light and tissues. LDF measures the mean blood flow in a volume formed by the single laser beam, that penetrate into the skin. The size of this measurement volume is crucial and depends on skin absorption, and is not directly reachable. Therefore, current developments of the LDF are focused on the use of always more complex and sophisticated signal processing methods. On the other hand, laser Double Doppler Flowmeter (FL2D) proposes to use two laser beams to generate the measurement volume. This volume would be perfectly stable and localized at the intersection of the two laser beams. With FL2D we will be able to determine the absolute blood flow of a specific artery. One aimed application would be to help clinical physicians in health care units.

  3. In vitro comparison of Doppler and catheter-measured pressure gradients in 3D models of mitral valve calcification.

    Science.gov (United States)

    Herrmann, Tarrah A; Siefert, Andrew W; Pressman, Gregg S; Gollin, Hannah R; Touchton, Steven A; Saikrishnan, Neelakantan; Yoganathan, Ajit P

    2013-09-01

    Mitral annular calcification (MAC) involves calcium deposition in the fibrous annulus supporting the mitral valve (MV). When calcification extends onto the leaflets, valve opening can be restricted. The influence of MAC MV geometry on Doppler gradients is unknown. This study describes a novel methodology to rapid-prototype subject-specific MAC MVs. Replicated valves were used to assess the effects of distorted annular-leaflet geometry on Doppler-derived, transmitral gradients in comparison to direct pressure measurements and to determine if transmitral gradients vary according to measurement location. Three-dimensional echocardiography data sets were selected for two MAC MVs and one healthy MV. These MVs were segmented and rapid prototyped in their middiastolic configuration for in vitro testing. The effects of MV geometry, measurement modality, and measurement location on transmitral pressure gradient were assessed by Doppler and catheter at three locations along the MV's intercommissural axis. When comparing dimensions of the rapid-prototyped valves to the subject echocardiography data sets, mean relative errors ranged from 6.2% to 35%. For the evaluated MVs, Doppler pressure gradients exhibited good agreement with catheter-measured gradients at a variety of flow rates, though with slight systematic overestimation in the recreated MAC valves. For all of the tested MVs, measuring the transmitral pressure gradient at differing valve orifice positions had minimal impact on observed gradients. Upon the testing of additional normal and calcific MVs, these data may contribute to an improved clinical understanding of MAC-related mitral stenosis. Moreover, they provide the ability to statistically evaluate between measurement locations, flow rates, and valve geometries for Doppler-derived pressure gradients. Determining these end points will contribute to greater clinical understanding for the diagnosis MAC patients and understanding the use and application of Doppler

  4. The use of echocardiography in acute cardiovascular care

    DEFF Research Database (Denmark)

    Lancellotti, Patrizio; Price, Susanna; Edvardsen, Thor

    2014-01-01

    of echocardiography in acute cardiovascular care. In this document, we describe the practical applications of echocardiography in patients with acute cardiac conditions, in particular with acute chest pain, acute heart failure, suspected cardiac tamponade, complications of myocardial infarction, acute valvular heart...... disease including endocarditis, acute disease of the ascending aorta and post-intervention complications. Specific issues regarding echocardiography in other acute cardiovascular care scenarios are also described....

  5. The use of echocardiography in acute cardiovascular care

    DEFF Research Database (Denmark)

    Lancellotti, Patrizio; Price, Susanna; Edvardsen, Thor

    2015-01-01

    of echocardiography in acute cardiovascular care. In this document, we describe the practical applications of echocardiography in patients with acute cardiac conditions, in particular with acute chest pain, acute heart failure, suspected cardiac tamponade, complications of myocardial infarction, acute valvular heart...... disease including endocarditis, acute disease of the ascending aorta and post-intervention complications. Specific issues regarding echocardiography in other acute cardiovascular care scenarios are also described....

  6. The use of echocardiography in acute cardiovascular care

    DEFF Research Database (Denmark)

    Lancellotti, Patrizio; Price, Susanna; Edvardsen, Thor

    2015-01-01

    of echocardiography in acute cardiovascular care. In this document, we describe the practical applications of echocardiography in patients with acute cardiac conditions, in particular with acute chest pain, acute heart failure, suspected cardiac tamponade, complications of myocardial infarction, acute valvular heart...... disease including endocarditis, acute disease of the ascending aorta and post-intervention complications. Specific issues regarding echocardiography in other acute cardiac care scenarios are also described....

  7. Echocardiography as a Research and Clinical Tool in Veterinary Medicine

    OpenAIRE

    Allen, D G

    1982-01-01

    Echocardiography is the accepted term for the study of cardiac ultrasound. Although a relatively new tool for the study of the heart in man it has already found wide acceptance in the area of cardiac research and in the study of clinical cardiac disease. Animals had often been used in the early experiments with cardiac ultrasound, but only recently has echocardiography been used as a research and clinical tool in veterinary medicine. In this report echocardiography is used in the research of ...

  8. Doppler ultrasound scan during normal gestation: umbilical circulation; Ecografia Doppler en la gestacion normal: circulacion umbilical

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, T.; Sabate, J.; Martinez-Benavides, M. M.; Sanchez-Ramos, J. [Hospital Virgen Macarena. Sevilla (Spain)

    2002-07-01

    To determine normal umbilical circulation patterns by means of Doppler ultrasound scan in a healthy gestating population without risk factors and with normal perinatal results, and to evaluate any occurring modifications relative to gestational age by obtaining records kept during pregnancy. One hundred and sixteen pregnant women carrying a single fetus have been studied. These women had no risk factors, with both clinical and analytical controls, as well as ultrasound scans, all being normal. There were performed a total of 193 Doppler ultrasound scans between weeks 15 and 41 of gestation, with blood-flow analysis in the arteries and vein of the umbilical cord. The obtained information was correlated with parameters that evaluate fetal well-being (fetal monitoring and/or oxytocin test) and perinatal result (delivery type, birth weight, Apgar score). Statistical analysis was performed with the programs SPSS 6.0.1 for Windows and EPIINFO 6.0.4. With pulsed Doppler, the umbilical artery in all cases demonstrated a biphasic morphology with systolic and diastolic components and without retrograde blood flow. As the gestation period increased, there was observed a progressive decrease in resistance along with an increase in blood-flow velocity during the diastolic phase. The Doppler ultrasound scan is a non-invasive method that permits the hemodynamic study of umbilical blood circulation. A knowledge of normal blood-flow signal morphology, as well as of the normal values for Doppler indices in relation to gestational age would permit us to utilize this method in high-risk pregnancies. (Author) 30 refs.

  9. Pulse on Pulse

    DEFF Research Database (Denmark)

    Schmidt, Ulrik; Carlson, Merete

    2012-01-01

    and pulsating ‘room’. Hence, the visitors in Pulse Room are invited into a complex scenario that continuously oscillates between various aspects of signification (the light bulbs representing individual lives; the pulse itself as the symbolic ‘rhythm of life’) and instants of pure material processuality......“Pulse on Pulse” investigates the relation between signifying processes and non-signifying material dynamism in the installation Pulse Room (2006-) by Mexican Canadian artist Rafael Lozano-Hemmer. In Pulse Room the sense of pulse is ambiguous. Biorhythms are transmitted from the pulsing energy...... of the visitor’s beating heart to the blink of a fragile light bulb, thereby transforming each light bulb into a register of individual life. But at the same time the blinking light bulbs together produce a chaotically flickering light environment composed by various layers of repetitive rhythms, a vibrant...

  10. Echocardiography is dispensable in uncomplicated Staphylococcus aureus bacteremia

    National Research Council Canada - National Science Library

    Khatib, Riad; Sharma, Mamta

    2013-01-01

    Current Staphylococcus aureus bacteremia (SAB) practice guidelines stratify treatment duration according to the likelihood of complications and recommend transesophageal echocardiography (TEE) in all cases...

  11. Development of all-solid coherent Doppler wind lidar

    Institute of Scientific and Technical Information of China (English)

    Xiaopeng Zhu; Jiqiao Liu; Decang Bi; Jun Zhou; Weifeng Diao; Weibiao Chen

    2012-01-01

    A 1064-nm pulsed coherent Doppler lidar (CDL) prototype is developed to measure short range wind speed in the lower altitude troposphere layer The CDL system adopts an injection seeded Nd:YAG laser with the pulse duration of 80 ns,single pulse energy of 0.5 m J,and pulse repetition rate of 200 Hz.Speed calibration experiments are implemented to obtain a speed accuracy of 0.3 m/s using a hard target.Data analysis results show that the CDL system can obtain a line-of-sight wind velocity at a range of 30 to 500m with the range resolution of 40 m and 38 pulses accumulation.

  12. Color Doppler sonography and angioscintigraphy in hepatic Hodgkin's lymphoma

    Institute of Scientific and Technical Information of China (English)

    Mirjana V Stojkovi(c); Vera M Artiko; Irena B Radoman; Slavko J Kne(z)evi(c); Snezana M Luki(c); Mirko D Kerkez; Nebojsa S Leki(c); Andrija A Anti(c); Marinko M (Z)vela; Vitomir I Rankovi(c); Milorad N Petrovi(c); Dragana P (S)obi(c); Vladimir B Obradovi(c)

    2009-01-01

    AIM: To estimate the characteristics of Color Doppler findings and the results of hepatic radionuclide angiography (HRA) in secondary Hodgkin's hepatic lymphoma.METHODS: The research included patients with a diagnosis of Hodgkin's lymphoma with metastatic focal lesions in the liver and controls. Morphologic characteristics of focal liver lesions and hemodynamic parameters were examined by pulsed and Color Doppler in the portal, hepatic and splenic veins were examined. Hepatic perfusion index (HPI) estimated by HRA was calculated.RESULTS: In the majority of patients, hepatomegaly was observed. Lesions were mostly hypoechoic and mixed, solitary or multiple. Some of the patients presented with dilated splenic veins and hepatofugal blood flow. A pulse wave was registered in the centre and at the margins of lymphoma. The average velocity of the pulse wave was higher at the margins ( P >0.05). A continuous venous wave was found only at the margins of lymphoma. There was no linear correlation between lymphoma size and velocity of pulse and continuous wave ( r = 390, P < 0.01). HPI was significantly lower in patients with lymphomas than in controls ( P < 0.05), pointing out increased arterial perfusion in comparison to portal perfusion.CONCLUSION: Color Doppler ultrasonography is a sensitive method for the detection of neovascularization in Hodgkin's hepatic lymphoma and estimation of its intensity. Hepatic radionuclide angiography can additionally help in the assesment of vascularisation of liver lesions.

  13. Physiology knowledge plays a role when novices learn technical echocardiography skills

    DEFF Research Database (Denmark)

    Nielsen, Dorte Guldbrand; Gøtzsche, Ole; Eika, Berit

    2010-01-01

    and interpretation skills of intermediately trained echocardiographers. This study investigates the role of physiology knowledge in the development of echocardiographic technical expertise. Methods: Forty-five physicians (15 novices, 15 intermediates and 15 experts) were evaluated on technical skills. Participants...... scanned a standardized patient and recorded pre-defined TTE images based on Danish Cardiology Society guidelines. Loops of 2D images and colour Doppler images were recorded as well as PW and CW curves. A structured checklist for evaluation of technical skills was developed. Two experts then graded each...... image recorded on the checklist from very poor (1) to very good (5). An average quality of images was calculated with 3 as the cut off for images suitable for interpretation. The echocardiography technical skills scores of the 45 physicians were then correlated with their scores on a MCQ test...

  14. Association Between Echocardiography Laboratory Accreditation and the Quality of Imaging and Reporting for Valvular Heart Disease.

    Science.gov (United States)

    Thaden, Jeremy J; Tsang, Michael Y; Ayoub, Chadi; Padang, Ratnasari; Nkomo, Vuyisile T; Tucker, Stephen F; Cassidy, Cynthia S; Bremer, Merri; Kane, Garvan C; Pellikka, Patricia A

    2017-08-01

    It is presumed that echocardiographic laboratory accreditation leads to improved quality, but there are few data. We sought to compare the quality of echocardiographic examinations performed at accredited versus nonaccredited laboratories for the evaluation of valvular heart disease. We enrolled 335 consecutive valvular heart disease subjects who underwent echocardiography at our institution and an external accredited or nonaccredited institution within 6 months. Completeness and quality of echocardiographic reports and images were assessed by investigators blinded to the external laboratory accreditation status and echocardiographic results. Compared with nonaccredited laboratories, accredited sites more frequently reported patient sex (94% versus 78%; Pheart disease. Future quality improvement initiatives should highlight the importance of high-quality color Doppler imaging and echocardiographic quantification to improve the accuracy, reproducibility, and quality of echocardiographic studies for valvular heart disease. © 2017 American Heart Association, Inc.

  15. Predicting and measuring fluid responsiveness with echocardiography

    Directory of Open Access Journals (Sweden)

    Ashley Miller

    2016-06-01

    Full Text Available Echocardiography is ideally suited to guide fluid resuscitation in critically ill patients. It can be used to assess fluid responsiveness by looking at the left ventricle, aortic outflow, inferior vena cava and right ventricle. Static measurements and dynamic variables based on heart–lung interactions all combine to predict and measure fluid responsiveness and assess response to intravenous fluid esuscitation. Thorough knowledge of these variables, the physiology behind them and the pitfalls in their use allows the echocardiographer to confidently assess these patients and in combination with clinical judgement manage them appropriately.

  16. Therapeutic implications of transesophageal echocardiography after transthoracic echocardiography on acute stroke patients

    Directory of Open Access Journals (Sweden)

    Tiago Tribolet de Abreu

    2008-02-01

    Full Text Available Tiago Tribolet de Abreu, Sonia Mateus, Cecilia Carreteiro, Jose CorreiaLaboratorio de Ultrasonografia Cardiaca e Neurovascular, Hospital do Espirito Santo-Evora, E. P. E., PortugalBackground: The role of transesophageal echocardiography (TEE in the evaluation of acute stroke patients is still ill-defined. We conducted a prospective observational study to find the prevalence of TEE findings that indicate anticoagulation as beneficial, in acute ischemic stroke patients without indication for anticoagulation based on clinical, electrocardiographic and transthoracic echocardiography (TTE findings.Methods: We prospectively studied all patients referred to our laboratory for TTE and TEE. Patients were excluded if the diagnosis was not acute ischemic stroke or if they had an indication for anticoagulation based on clinical, electrocardiographic, or TTE data. Patients with TEE findings that might indicate anticoagulation as beneficial were identified.Results: A total of 84 patients with acute ischemic stroke and without indication for anticoagulation based on clinical and electrocardiographic or TTE data were included in the study. Findings indicating anticoagulation as beneficial were found in 32.1%: spontaneous echo contrast (1.2%, complex aortic atheroma (27.4%, thrombus (8.3%, and simultaneous patent foramen ovale and atrial septal aneurysm (2.4%.Conclusions: The results of our study show that TEE can have therapy implications in 32.1% of ischemic stroke patients in sinus rhythm and with TTE with no indication for anticoagulation.Keywords: acute ischemic stroke, transesophageal echocardiography, transthoracic echocardiography, therapy

  17. X-Band to W-Band Doppler Radar Using Reconfigurable RF T/R MMIC Series Project

    Data.gov (United States)

    National Aeronautics and Space Administration — TLC demonstrated a high performance remote Doppler Radar adjustable X-band to W-band transceiver chip that can perform well as a FMCW, super-heterodyne or pulse...

  18. An Experimental Study of Myocardial Viability with Myocardial Contrast Echocardiography

    Institute of Scientific and Technical Information of China (English)

    张稳柱; 查道刚; 成官迅; 杨绍青; 刘伊丽

    2001-01-01

    Background Myocardial blood flow(MBF) can be quantified with myocardial contrast echocardiography (MCE) during a venous in fusion of microbubble. A minimal MBF is required to maintain cell membrane integrity and myocardial viability in ischemic condition. Thus, we hypothesized that MCE could be used to assess myocardial viability by the determination of MBF. Methods and Results MCE was performed at 4 hours after ligation of proximal left anterior descending coronary artery in 7dogs with constant venous infusions of microbubbles.The video intensity versus pulsing interval plots derived from each myocardial pixel were fitted to an exponential function: y=A(1-e-βt), where y is Ⅵ at pulsing interval t, A reflects rnicrovascular cross- sectional area (or myocardial blood volume), and β reflects mean myocardial microbubble velocity. The product of A · β represents MBF. MBF was also obtained by radiolabeled microsphere method servered as reference.MBF derived by radiolabeled microsphere- method in the regions of normal, ischemia and infarction was 1.5±0.3, 0.7±0.3, 0.3±0.2mL·min-1· g-1respectively. The product of A · β obtained by MCE in those regions was 52. 46 ± 15.09, 24.36 ± 3.89, 3.74± ± 3.80 respectively. There was good correlation between normalized MBF and the normalized A · β (r =0. 81, P = 0. 001 ). Conclusions MCE has an ability to determine myocardial viability in myocardial in farction canine model.

  19. Clinical utility of speckle-tracking echocardiography in cardiac resynchronisation therapy

    Directory of Open Access Journals (Sweden)

    Sitara G Khan

    2016-05-01

    Full Text Available Cardiac resynchronisation therapy (CRT can profoundly improve outcome in selected patients with heart failure; however, response is difficult to predict and can be absent in up to one in three patients. There has been a substantial amount of interest in the echocardiographic assessment of left ventricular dyssynchrony, with the ultimate aim of reliably identifying patients who will respond to CRT. The measurement of myocardial deformation (strain has conventionally been assessed using tissue Doppler imaging (TDI, which is limited by its angle dependence and ability to measure in a single plane. Two-dimensional speckle-tracking echocardiography is a technique that provides measurements of strain in three planes, by tracking patterns of ultrasound interference (‘speckles’ in the myocardial wall throughout the cardiac cycle. Since its initial use over 15 years ago, it has emerged as a tool that provides more robust, reproducible and sensitive markers of dyssynchrony than TDI. This article reviews the use of two-dimensional and three-dimensional speckle-tracking echocardiography in the assessment of dyssynchrony, including the identification of echocardiographic parameters that may hold predictive potential for the response to CRT. It also reviews the application of these techniques in guiding optimal LV lead placement pre-implant, with promising results in clinical improvement post-CRT.

  20. Clinical utility of speckle-tracking echocardiography in cardiac resynchronisation therapy.

    Science.gov (United States)

    Khan, Sitara G; Klettas, Dimitris; Kapetanakis, Stam; Monaghan, Mark J

    2016-03-01

    Cardiac resynchronisation therapy (CRT) can profoundly improve outcome in selected patients with heart failure; however, response is difficult to predict and can be absent in up to one in three patients. There has been a substantial amount of interest in the echocardiographic assessment of left ventricular dyssynchrony, with the ultimate aim of reliably identifying patients who will respond to CRT. The measurement of myocardial deformation (strain) has conventionally been assessed using tissue Doppler imaging (TDI), which is limited by its angle dependence and ability to measure in a single plane. Two-dimensional speckle-tracking echocardiography is a technique that provides measurements of strain in three planes, by tracking patterns of ultrasound interference ('speckles') in the myocardial wall throughout the cardiac cycle. Since its initial use over 15 years ago, it has emerged as a tool that provides more robust, reproducible and sensitive markers of dyssynchrony than TDI. This article reviews the use of two-dimensional and three-dimensional speckle-tracking echocardiography in the assessment of dyssynchrony, including the identification of echocardiographic parameters that may hold predictive potential for the response to CRT. It also reviews the application of these techniques in guiding optimal LV lead placement pre-implant, with promising results in clinical improvement post-CRT. © 2016 The authors.

  1. From speckle tracking echocardiography to torsion: research tool today, clinical practice tomorrow.

    Science.gov (United States)

    Huang, Stephen J; Orde, Sam

    2013-06-01

    Speckle tracking is the latest available technology in echocardiography. However, the technology is still mainly used as a research tool. The potential applications of speckle tracking are many, including cardiac synchronization, regional wall motion analysis, and in the areas of cardiac mechanic studies. This review presents the background theory of speckle tracking echocardiography (STE) and how this technology can be extended to velocity vector analysis, strain, and torsion measurements. The interpretations of these measurements are covered. We also present some potential applications in the critical care setting. Speckle tracking is almost always available in high-end ultrasound machines. The technology has been applied to velocity vector analysis, strain and strain rate measurements, and twist and torsion analysis. Torsion analysis and velocity vector analyses are impossible without using speckle tracking. Speckle tracking-derived strain is superior to tissue Doppler strain because it is angle-independent. A number of studies demonstrated that STE is useful in left and right heart assessments and can be used in assessing preload and afterload. Speckle tracking can be used to measure instantaneous myocardial contractility, strain, and left ventricular torsion. It is still a research tool at present, but shows the promise of being a clinical tool in the future.

  2. Exercise treadmill saline contrast echocardiography for the detection of patent foramen ovale in hypoxia.

    Science.gov (United States)

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

    2015-12-01

    Percutaneous patent foramen ovale (PFO) occluder placement improves dyspnea and oxygen requirement in hypoxic patients with PFO-mediated right-to-left shunt (RTLS). Although saline contrast echocardiography (SCE) in the resting state can identify PFO RTLS, SCE performed with exercise stress testing may provide incremental diagnostic yield compared to rest SCE. We evaluated the ability of exercise SCE to predict PFO presence and size using intracardiac echocardiography (ICE) as a gold standard in a hypoxic cohort. Thirty-three hypoxic patients with suspected PFO RTLS who underwent rest, Valsalva, and exercise stress SCE prior to ICE were evaluated retrospectively. PFO RTLS was defined by ICE findings including PFO anatomy, RTLS by saline contrast and color Doppler, and probe patency. SCE shunt severity was compared to the presence of ICE-defined PFO RTLS and PFO size. Exercise SCE for the detection of PFO RTLS performed with an area under the curve of 0.77, sensitivity of 73%, and specificity of 86%. Among 26 patients with PFO RTLS, exercise SCE identified four additional patients with PFO that had negative rest SCE and two patients with negative Valsalva SCE. Exercise SCE had a stronger correlation with PFO size than resting or Valsalva SCE. Exercise SCE detects PFO RTLS and predicts PFO size in a hypoxic cohort. In addition, exercise SCE can identify PFO RTLS that is otherwise undetected with rest or Valsalva SCE. Exercise SCE may be appropriate when a clinical suspicion for PFO RTLS persists despite negative rest and Valsalva SCE.

  3. ANL Doppler flowmeter

    Science.gov (United States)

    Karplus, H. B.; Raptis, A. C.; Lee, S.; Simpson, T.

    1985-10-01

    A flowmeter has been developed for measuring flow velocity in hot slurries. The flowmeter works on an ultrasonic Doppler principle in which ultrasound is injected into the flowing fluid through the solid pipe wall. Isolating waveguides separate the hot pipe from conventional ultrasonic transducers. Special clamp-on high-temperature transducers also can be adapted to work well in this application. Typical flows in pilot plants were found to be laminar, giving rise to broad-band Doppler spectra. A special circuit based on a servomechanism sensor was devised to determine the frequency average of such a broad spectrum. The device was tested at different pilot plants. Slurries with particulates greater than 70 microns (0.003 in.) yielded good signals, but slurries with extremely fine particulates were unpredictable. Small bubbles can replace the coarse particles to provide a good signal if there are not too many. Successful operation with very fine particulate slurries may have been enhanced by the presence of microbubbles.

  4. Prognostic value of clinical and Doppler echocardiographic findings in children and adolescents with significant rheumatic valvular disease

    Directory of Open Access Journals (Sweden)

    Fátima Derlene da Rocha Araújo

    2012-01-01

    Conclusions: Our study suggests that the use of Doppler echocardiography during RF helps to identify prognostic factors regarding the development of significant valvular heart disease. Initial severe carditis is an important factor in the long-term prognosis of chronic RHD, whereas arthritis and chore during the initial episode of RF appears to be protective. Strict secondary prophylaxis should be mandatory in high risk patients.

  5. A novel platform device for rodent echocardiography.

    Science.gov (United States)

    Kutschka, Ingo; Sheikh, Ahmad Y; Sista, Ramachandra; Hendry, Stephen L; Chun, Hyung J; Hoyt, Grant; Kutschka, Werner; Pelletier, Marc P; Quertermous, Tom; Wu, Joseph C; Robbins, Robert C

    2007-06-06

    Acquisition of echocardiographic data from rodents is subject to wide variability due to variations in technique. We hypothesize that a dedicated imaging platform can aid in standardization of technique and improve the quality of images obtained. We constructed a device consisting of a boom-mounted steel platform frame (25 x 35 x 3 cm) on which a transparent polyethylene membrane is mounted. The animal is placed onto the membrane and receives continual inhaled anesthesia via an integrated port. The membrane allows for probe positioning from beneath the animal to obtain standard echo-views in left lateral decubitus or prone positions. The frame can be set at any desired angle ranging from 0 to 360 degrees along either the long or short axis. Adult male Sprague-Dawley rats (n = 5) underwent echocardiography (General Electric, Vivid 7, 14 MHz) using the platform. The device allowed for optimal positioning of animals for a variety of standard echocardiographic measurements. Evaluations among all animals showed minimal variability between two different operators and time points. We tested the feasibility of the device for supporting the assessment of cardiac function in a disease model by evaluating a separate cohort of adult male spontaneously hypertensive rats (n = 5) that underwent left anterior descending coronary artery ligation. Serial echocardiography demonstrated statistically significant decreases of fractional shortening and ejection fraction (p rats. Future studies will focus on improving this technology to allow for standardized high-throughput echocardiographic analysis in small animal models of disease.

  6. Laser Doppler Imaging of Microflow

    CERN Document Server

    Gross, Michel; Leng, Jacques

    2013-01-01

    We report a pilot study with a wide-field laser Doppler detection scheme used to perform laser Doppler anemometry and imaging of particle seeded microflow. The optical field carrying the local scatterers (particles) dynamic state, as a consequence of momentum transfer at each scattering event, is analyzed in the temporal frequencies domain. The setup is based on heterodyne digital holography, which is used to map the scattered field in the object plane at a tunable frequency with a multipixel detector. We show that wide-field heterodyne laser Doppler imaging can be used for quantitative microflow diagnosis; in the presented study, maps of the first-order moment of the Doppler frequency shift are used as a quantitative and directional estimator of the Doppler signature of particles velocity.

  7. Short period ionospheric perturbations from continuous Doppler sounding

    Science.gov (United States)

    Fiser, Jiri; Chum, Jaroslav; Lastovicka, Jan; Buresova, Dalia

    2017-04-01

    Results of recent observations of ionospheric perturbations on short time scales obtained by international network (Czech Republic, Argentina, Taiwan and South Africa) of multipoint continuous Doppler sounders with time resolution about 10 s are presented. Examples of observation and analysis of propagation of gravity waves (GWs), equatorial spread F (ESF), infrasound from earthquake and large convective systems, as well as ionospheric perturbations caused by solar flares will be shown. It is documented that roughly poleward propagation of GWs dominates in the local summer, whereas mainly equatorward propagation is observed in the local winter. The analysis of occurrences and zonal drifts of ESF based on Doppler sounding are consistent with optical and satellite measurements. The observations of co-seismic perturbations by Doppler sounders in the vicinity of ionosondes and seismic sensors proved that the co-seismic perturbations are caused by approximately vertically propagating infrasound waves triggered by vertical motion of the ground surface. Numerical simulations and Doppler measurements confirmed that in the vicinity (up to about 1000 km) from epicenters of strong earthquake, the infrasound propagates in nonlinear regime in the upper atmosphere, which results in the formation of N-shaped pulse. Solar flares are observed both as sudden frequency deviations and amplitude attenuations of Doppler signal.

  8. Generalized tetany: an unusual complication during dobutamine stress echocardiography.

    Science.gov (United States)

    Abbas, Amr E; Loftis, Rochelle; Lester, Steven J; Crawford, Michael B; Appleton, Christopher P

    2002-11-01

    Dobutamine stress echocardiography is a frequently used noninvasive method for the evaluation of inducible myocardial ischemia, myocardial viability, and preoperative cardiac risk. Although its clinical safety has been validated, side effects and complications especially with the coadministration of atropine can occur. We report a case of generalized tetany in a 49-year-old woman undergoing dobutamine stress echocardiography.

  9. Advanced quantitative echocardiography in arrhythmogenic right ventricular cardiomyopathy

    DEFF Research Database (Denmark)

    Kjaergaard, Jesper; Hastrup Svendsen, Jesper; Sogaard, Peter

    2007-01-01

    of global and regional function, but the diagnostic potential remains to be assessed. METHODS: Twenty patients with previously established ARVC were evaluated by 3-dimensional echocardiography and DTI, and compared with 32 age- and sex-matched control subjects. RESULTS: Using 3-dimensional echocardiography...

  10. Automated analysis of three-dimensional stress echocardiography

    NARCIS (Netherlands)

    K.Y.E. Leung (Esther); M. van Stralen (Marijn); M.G. Danilouchkine (Mikhail); G. van Burken (Gerard); M.L. Geleijnse (Marcel); J.H.C. Reiber (Johan); N. de Jong (Nico); A.F.W. van der Steen (Ton); J.G. Bosch (Johan)

    2011-01-01

    textabstractReal-time three-dimensional (3D) ultrasound imaging has been proposed as an alternative for two-dimensional stress echocardiography for assessing myocardial dysfunction and underlying coronary artery disease. Analysis of 3D stress echocardiography is no simple task and requires considera

  11. Advances in the Evaluation of Cardiovascular Function by Echocardiography

    NARCIS (Netherlands)

    A. Nemes (Attila)

    2007-01-01

    textabstractThe aim of this thesis was to study the advances in the evaluation of cardiovascular function by 2D and real-time 3D stress echocardiography and vascular stiffness measurements. Stress echocardiography is a widely used non-invasive stress modality for the detection of coronary artery dis

  12. Echocardiography may help detect pulmonary vasculopathy in the early stages of pulmonary artery hypertension associated with systemic sclerosis

    Directory of Open Access Journals (Sweden)

    Serra Walter

    2010-07-01

    Full Text Available Abstract Background Pulmonary arterial hypertension (PAH in patients with systemic sclerosis is associated with a poor prognosis, but this can be improved by early disease detection. Abnormal pulmonary and cardiac function can be detected early by means of echocardiography, whereas right heart catheterization is usually performed later. Objectives The purpose of this prospective study was to detect early the presence of pulmonary artery vasculopathy in patients with verified systemic sclerosis without significant pulmonary fibrosis, normal lung volumes and a mildly reduced lung diffusion capacity of carbon monoxide (DLCO. Methods Nineteen consecutive female NYHA class I-II patients with scleroderma and a PAPs of 2. They all underwent complete Doppler echocardiography, CPET, a pulmonary ventilation test (carbon monoxide lung diffusion, DLCO, HRCT. To investigate PAH by means of complete resting Doppler echocardiography estimates of systolic pulmonary artery pressure (PAPs derived from tr icuspid regurgitation, mean PAP derived from pulmonary regurgitation, pulmonary vessel resistance (PVR derived from the acceleration time of the pulmonary outflow tract (ACTpo, and right ventricular function derived from tricuspid annular plane systolic excursion (TAPSE. Right heart catheterisation was conducted only, if pulmonary hypertension was suggested by echocardiography and an abnormal ventilator test. The data are given as mean values ± SD, unless otherwise stated. The correlations between the variables were analysed using Pearson's r coefficient, and the predictive value of the variables was calculated using linear regression analysis. A p value of > 0.05 was considered significant. Results Right heart catheterization detected PAH in 15/19 patients; mean PAP was 30.5 mm/Hg and RVP 3.6 UW. Coronary angiography of the patients aged more than 55 years showed some evidence of significant coronary artery disease. Echocardiography showed high systolic PAP

  13. MODERN POSSIBILITIES OF SPECKLE TRACKING ECHOCARDIOGRAPHY IN CLINICAL PRACTICE

    Directory of Open Access Journals (Sweden)

    V. S. Nikiforov

    2017-01-01

    Full Text Available Speckle-tracking echocardiography is promising modern technique for evaluation of structural and functional changes in the myocardium. It evaluates the indicator of global longitudinal myocardial deformation, which is more sensitive than ejection fraction to early changes of left ventricular contractility. The diagnostic capabilities of speckle tracking echocardiography are reflected in clinical recommendations and consensus statements of European Society of Cardiology (ESC, European Association of Cardiovascular Imaging (EACVI and American Society of Echocardiography (ASE. The aim of this paper is describe basic principles of speckle tracking echocardiography and clinical applications of this new technology. Attention is paid to the use of speckle tracking echocardiography in such heart pathologies as heart failure, coronary heart disease and myocardial infarction, left ventricular hypertrophy in arterial hypertension, hypertrophic cardiomyopathy and amyloidosis of the heart, valvular heart disease, constrictive pericarditis and cancer therapy-induced cardiotoxicity.

  14. Acute regional improvement of myocardial function after interventional transfemoral aortic valve replacement in aortic stenosis: A speckle tracking echocardiography study

    Directory of Open Access Journals (Sweden)

    Schattke Sebastian

    2012-03-01

    Full Text Available Abstract Background Transcatheter aortic valve implantation (TAVI is a promising therapy for patients with severe aortic stenosis (AS and high perioperative risk. New echocardiographic methods, including 2D Strain analysis, allow the more accurate measurement of left ventricular (LV systolic function. The goal of this study was to describe the course of LV reverse remodelling immediately after TAVI in a broad spectrum of patients with symptomatic severe aortic valve stenosis. Methods Thirty consecutive patients with symptomatic aortic valve stenosis and preserved LVEF underwent transfemoral aortic valve implantation. We performed echocardiography at baseline and one week after TAVI. Echocardiography included standard 2D and Doppler analysis of global systolic and diastolic function as well as 2D Strain measurements of longitudinal, radial and circumferential LV motion and Tissue Doppler echocardiography. Results The baseline biplane LVEF was 57 ± 8.2%, the mean pressure gradient was 46.8 ± 17.2 mmHg and the mean valve area was 0.73 ± 0.27 cm2. The average global longitudinal 2D strain of the left ventricle improved significantly from -15.1 (± 3.0 to -17.5 (± 2.4 % (p Conclusion There is an acute improvement of myocardial longitudinal systolic function of the basal and medial segments measured by 2D Strain analysis immediately after TAVI. The radial, circumferential strain and LVEF does not change significantly in all patients acutely after TAVI. These data suggest that sensitive new echo methods can reliably detect early regional changes of myocardial function after TAVI before benefits in LVEF are detectable.

  15. The assessment of cardiac functions by tissue Doppler-derived myocardial performance index in patients with Behcet's disease.

    Science.gov (United States)

    Tavil, Yusuf; Ozturk, Mehmet Akif; Sen, Nihat; Kaya, Mehmet Gungor; Hizal, Fatma; Poyraz, Fatih; Turfan, Murat; Onder, Meltem; Gurer, Mehmet Ali; Cengel, Atiye

    2008-03-01

    Vascular involvement is one of the major characteristics of Behcet's disease (BD). However, there are controversial findings regarding cardiac involvement in BD. Although early reports demonstrated that there is diastolic dysfunction in BD, conflicting results were found in the following trials. Hence, a new method for more objectively estimating the cardiac functions is needed. For this aim, we used high-usefulness tissue Doppler echocardiography for detailed analysis of cardiac changes in BD patients because this method was superior to other conventional echocardiographic techniques. The study population included 42 patients with BD (19 men, 23 women; mean age, 35 +/- 10 years, mean disease duration, 2.7 +/- 1.6 years) and 30 healthy subjects (14 men, 16 women; mean age, 38 +/- 7 years). Cardiac functions were determined using echocardiography, comprising standard two-dimensional and conventional Doppler and tissue Doppler imaging (TDI). Peak systolic myocardial velocity at mitral annulus, early diastolic mitral annular velocity (Em), late diastolic mitral annular velocity (Am), Em/Am, and myocardial performance index (MPI) were calculated by TDI. The conventional echocardiographic parameters and tissue Doppler measurements were similar between the groups. Tissue Doppler derived mitral relaxation time was longer (75 +/- 13 vs 63 +/- 16 msn, p = 0.021) in patients with BD. There was statistically significant difference between the two groups regarding left ventricular MPI (0.458 +/- 0.072 vs 0.416 +/- 0.068%, p = 0.016), which were calculated from tissue Doppler systolic time intervals. There was also significant correlation between the disease duration and MPI (r = 0.38, p = 0.017). We have demonstrated that tissue Doppler-derived myocardial left ventricular relaxation time and MPI were impaired in BD patients, although systolic and diastolic function parameters were comparable in the patients and controls.

  16. Tissue Doppler Findings in Patients with Pulmonary Arterial Hypertension

    Directory of Open Access Journals (Sweden)

    Firoozeh Abtahi

    2016-09-01

    Full Text Available In conclusion, our results suggested that increasing degrees of pulmonary artery systolic pressure affected timing of some tissue Doppler-derived intervals within the cardiac cycle, including IVC time, time to peak systolic myocardial velocity (Sm, and time to peak strain. Therefore, tissue Doppler imaging could be used in assessment of patients with suspected pulmonary arterial hypertension. Background: Pulmonary hypertension is an untreatable condition with poor prognosis and factors such as more elevated pulmonary arterial systolic pressure and right ventricular dysfunction are associated with a worse outcome. Objectives: Considering the limitations of the current modalities, this study aimed to find the relationship between tissue Doppler-derived systolic and diastolic parameters and elevated pulmonary arterial pressure in order to assess the routine application of tissue Doppler imaging in evaluation of pulmonary arterial hypertension. Patients and Methods: This study was conducted on 100 inpatient and outpatient individuals referred to the Department of Echocardiography in Shahid Faghihi hospital, Shiraz, Iran from July 2012 to March 2013. The individuals who had preserved right ventricular function in the presence of pulmonary arterial hypertension were included in the case group. On the other hand, the patients who did not have echocardiographic signs of pulmonary arterial hypertension were enrolled into the control group. All the patients underwent a complete transthoracic echocardiogram including 2-dimensional, color flow, and spectral Doppler as well as tissue Doppler imaging using a vivid E9 system, and the desired systolic and diastolic parameters were recorded. The relationship among these parameters was evaluated by independent sample t-test using the SPSS statistical software, version 16. Besides, P < 0.05 was considered to be statistically significant. Results: The mean time to peak strain was significantly longer in the case

  17. Doppler Compensation by using of Segmented Match Filter

    OpenAIRE

    2008-01-01

    Match filter is one of the important parts of radar receiver. By using of Match Filter, the signal to noise ratio can be maximized so that the probability of detection is increased. Match Filter can be used as a pulse compression filter in radar receiver. Binary phase code is one of the pulse compression methods that, the compression can be down with a Match Filter in the receiver. Doppler effect is one of the problems that degrade the performance of Match Filter. In this paper, two methods “...

  18. Prognostic value of tissue Doppler imaging for predicting ventricular arrhythmias and cardiovascular mortality in ischaemic cardiomyopathy

    DEFF Research Database (Denmark)

    Biering-Sørensen, Tor; Olsen, Flemming Javier; Storm, Katrine;

    2016-01-01

    AIMS: Only 30% of patients receiving an implantable cardioverter defibrillator (ICD) for primary prevention receive appropriately therapy. We sought to investigate the value of tissue Doppler imaging (TDI) to predict ventricular tachycardia (VT), ventricular fibrillation (VF), and cardiovascular...... mortality (CVD) in patients with primary prevention ICD. METHODS AND RESULTS: In total, 151 ICD patients meeting primary prevention criteria and with no history of ventricular arrhythmias were included. All participants were examined by conventional 2D echocardiography and TDI echocardiography. Longitudinal...... systolic (s'), early diastolic (e'), and late diastolic (a') myocardial velocities were measured using TDI at six mitral annular sites and averaged to provide global estimates. Forty patients experienced the combined endpoint of VT, VF, or CVD during a median follow-up of 2.3 years. Left ventricular...

  19. Speckle tracking echocardiography in the critically ill: enticing research with minimal clinical practicality or the answer to non-invasive cardiac assessment?

    Science.gov (United States)

    Orde, S; Huang, S J; McLean, A S

    2016-09-01

    Echocardiography is developing rapidly. Speckle tracking echocardiography is the latest semi-automatic tool that has potential to quantitatively describe cardiac dysfunction that may be unrecognised by conventional echocardiography. It is a non-Doppler, angle-independent, feasible and reproducible method to evaluate myocardial function in both non-critically ill and critically ill populations. Increasingly it has become a standard measure of both left and right ventricle function in specific patient groups, e.g. chemotherapy-induced cardiomyopathy or pulmonary hypertension. To date there are few studies in the critically ill, predominantly in sepsis, yet all describe dysfunction beyond standard measures. Other areas of interest include heart-lung interactions, right ventricle function and twist and torsion of the heart. A word of caution is required, however, in that speckle tracking echocardiography is far from perfect and is more challenging, particularly in the critically ill, than implied by many published studies. It takes time to learn and perform and most values are not validated, particularly in the critically ill. We should be cautious in accepting that the latest software used in cardiology cohorts will automatically be the answer in the critically ill. Even with these limitations the technology is enticing and results fascinating. We are uncovering previously undescribed dysfunction and although it currently is essentially a research-based activity, there is great promise as a clinical tool as echocardiography analysis becomes more automated, and potentially speckle tracking echocardiography could help describe cardiac function in critical illness more accurately than is possible with current techniques.

  20. Stress echocardiography in patients with morbid obesity

    Directory of Open Access Journals (Sweden)

    Benoy N Shah

    2016-06-01

    Full Text Available The incidence of significant obesity is rising across the globe. These patients often have a clustering of cardiovascular risk factors and are frequently referred for noninvasive cardiac imaging tests. Stress echocardiography (SE is widely used for assessment of patients with known or suspected coronary artery disease (CAD, but its clinical utility in morbidly obese patients (in whom image quality may suffer due to body habitus has been largely unknown. The recently published Stress Ultrasonography in Morbid Obesity (SUMO study has shown that SE, when performed appropriately with ultrasound contrast agents (whether performed with physiological or pharmacological stress, has excellent feasibility and appropriately risk stratifies morbidly obese patients, including identification of patients who require revascularization. This article reviews the evidence supporting the use of echocardiographic techniques in morbidly obese patients for assessment of known or suspected CAD and briefly discusses other noninvasive modalities, including magnetic resonance and nuclear techniques, comparing and contrasting these techniques against SE.

  1. Evaluation of factors influencing arterial Doppler waveforms in an in vitro flow phantom

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Chang Kyu [Dept. of Radiology, SMG-SNU Boramae Medical Center, Seoul National University College of Medicine, Seoul (Korea, Republic of); Lee, Kyoung Ho [Dept. of Radiology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam (Korea, Republic of); Kim, Seung Hyup [Dept. of Radiology and the Institute of Radiation Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2017-01-15

    The aim of this study was to investigate factors that influence arterial Doppler waveforms in an in vitro phantom to provide a more accurate and comprehensive explanation of the Doppler signal. A flow model was created using a pulsatile artificial heart, rubber or polyethylene tubes, a water tank, and a glass tube. Spectral Doppler tracings were obtained in multiple combinations of compliance, resistance, and pulse rate. Peak systolic velocity, minimum diastolic velocity, resistive index (RI), pulsatility index, early systolic acceleration time, and acceleration index were measured. On the basis of these measurements, the influences of the variables on the Doppler waveforms were analyzed. With increasing distal resistance, the RI increased in a relatively linear relationship. With increasing proximal resistance, the RI decreased. The pulsus tardus and parvus phenomenon was observed with a small acceleration index in the model with a higher grade of stenosis. An increase in the distal resistance masked the pulsus tardus and parvus phenomenon by increasing the acceleration index. Although this phenomenon occurred independently of compliance, changes in the compliance of proximal or distal tubes caused significant changes in the Doppler waveform. There was a reverse relationship between the RI and the pulse rate. Resistance and compliance can alter the Doppler waveforms independently. The pulse rate is an extrinsic factor that also influences the RI. The compliance and distal resistance, as well as proximal resistance, influence the pulsus tardus and parvus phenomenon.

  2. THE ROLE OF SPECKLE-TRACKING ECHOCARDIOGRAPHY TECHNIQUE AT THE STAGE OF SUBCLINICAL HEART TRANSPLANT REJECTION

    Directory of Open Access Journals (Sweden)

    T. V. Stavenchuk

    2015-01-01

    Full Text Available Aim. To identify new predictors of heart transplant rejection by using speckle-tracking echocardiography technique. Materials and methods. 117 recipients were included into research. The follow-up period in S.V. Ochapovsky Region Clinical Hospital No 1 was from March 2010 to April 2015. The groups were allocated based on results of the retrospective analysis of biopsies: group 1 (n = 68, recipients without signs of cellular and humoral rejection (AMR0 ACR0; group 2 (n = 28, recipients with ACR1; group 3 (n = 16, patients with ACR2; group 4 (n = 5, patients with chronic rejection. The analysis of the results was carried out with endomyocardial biopsy, coronary angiography, transthoracic echocardiography (TTE, tissue Doppler imaging, speckle-tracking echocardiography. Results. Early complications include infections and rejection of heart transplant. Cellular rejection is diagnosed in 70% of cases, humoral rejection in 30% of cases. The disease of coronary arteries is a kind of late complications. It was diagnosed in 13.7%. Fraction rejection sensitivity was 63%, specificity was 97% in recipients with ACR1 while carrying out TTE for the purpose of identification of early diagnostic criterion of rejection; recipients with ACR2 had 75% and 96%, respectively. While carrying out PW sensitivity and specificity Е/А in recipients with ACR1 were 83% and 53%, respectively; recipients with ACR2 had 85% and 52%, respectively. While carrying out PW-TDI sensitivity and specificity Е in recipients with ACR1 were 83% and 58%, respectively; recipients with ACR2 had 88% and 60%, respectively. The assessment of myocardial deformation of the left ventricle is as follows: global peak systolic strain in recipients without rejection (GLPS LV – (–17.54 ± 3.71%, р = 0.0012; recipients with (ACR1, AMR1 had GLPS LV (–10.52 ± 1.8%, p = 0.0012; recipients with ACR2 had (–6.44 ± 1.8%, p = 0.002; recipients with chronic rejection had (–9.43 ± 1.8%, p = 0

  3. Atherosclerotic Aortic Plaques Detected by Transesophageal Echocardiography

    Institute of Scientific and Technical Information of China (English)

    赵云; 朱文玲; 倪超; 郭丽琳; 曾勇; 方理刚

    2002-01-01

    Objective To evaluate the predictive value of atherosclerotic aortic plaques in coronary artery disease (CAD) Methods In 50patients with suspected coronary artery disease, transesophageal echocardiography was performed to examine their thoracic aortas 2 weeks before or after coronary angiography. In the cases of coronary angiography studied, stenosis of the coronary artery ≥ 50 % was considered to be due to coronary artery disease,whereas the thickness of the intima ≥ 1.3 mm was taken to be the criteria for the presence of an atherosclerotic aortic plaque on the transesophageal echocardiographic test. Results Among the 50 patients, 37 cases were diagnosed as CAD and 13 cases were considered to be normal. The plaques of the thoracic aorta were observed in 34cases in the CAD group and 3 cases in the normal group. The sensitivity and specificity of aortic plaques for CAD were 91.9 % and 76.9%, respectively. The positive and negative predictive values of the aortic plaques for CAD were 91.9% and 76.9%, respectively. The accuracy was 88.0%. 80 percent of the patients with single- yes sel disease had thoracic aortic plaques, 92 percent of the patients with two-vessel disease and 100 percent of the patients with three-vessel disease had thoracic aortic plaques. There was a significant difference in the thickness of aortic intimas between the normal group and the CAD group. Conclusions Detectingatherosclerotic plaques in the thoracic aorta with transesophageal echocardiography may be of great value in predicting the presence and extent of coronary artery disease.

  4. Doppler characteristics of sea clutter.

    Energy Technology Data Exchange (ETDEWEB)

    Raynal, Ann Marie; Doerry, Armin Walter

    2010-06-01

    Doppler radars can distinguish targets from clutter if the target's velocity along the radar line of sight is beyond that of the clutter. Some targets of interest may have a Doppler shift similar to that of clutter. The nature of sea clutter is different in the clutter and exo-clutter regions. This behavior requires special consideration regarding where a radar can expect to find sea-clutter returns in Doppler space and what detection algorithms are most appropriate to help mitigate false alarms and increase probability of detection of a target. This paper studies the existing state-of-the-art in the understanding of Doppler characteristics of sea clutter and scattering from the ocean to better understand the design and performance choices of a radar in differentiating targets from clutter under prevailing sea conditions.

  5. Dual-Doppler Feasibility Study

    Science.gov (United States)

    Huddleston, Lisa L.

    2012-01-01

    When two or more Doppler weather radar systems are monitoring the same region, the Doppler velocities can be combined to form a three-dimensional (3-D) wind vector field thus providing for a more intuitive analysis of the wind field. A real-time display of the 3-D winds can assist forecasters in predicting the onset of convection and severe weather. The data can also be used to initialize local numerical weather prediction models. Two operational Doppler Radar systems are in the vicinity of Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS); these systems are operated by the 45th Space Wing (45 SW) and the National Weather Service Melbourne, Fla. (NWS MLB). Dual-Doppler applications were considered by the 45 SW in choosing the site for the new radar. Accordingly, the 45th Weather Squadron (45 WS), NWS MLB and the National Aeronautics and Space Administration tasked the Applied Meteorology Unit (AMU) to investigate the feasibility of establishing dual-Doppler capability using the two existing systems. This study investigated technical, hardware, and software requirements necessary to enable the establishment of a dual-Doppler capability. Review of the available literature pertaining to the dual-Doppler technique and consultation with experts revealed that the physical locations and resulting beam crossing angles of the 45 SW and NWS MLB radars make them ideally suited for a dual-Doppler capability. The dual-Doppler equations were derived to facilitate complete understanding of dual-Doppler synthesis; to determine the technical information requirements; and to determine the components of wind velocity from the equation of continuity and radial velocity data collected by the two Doppler radars. Analysis confirmed the suitability of the existing systems to provide the desired capability. In addition, it is possible that both 45 SW radar data and Terminal Doppler Weather Radar data from Orlando International Airport could be used to alleviate any

  6. Novel instantaneous laser Doppler velocimeter.

    Science.gov (United States)

    Avidor, J M

    1974-02-01

    A laser Doppler velocimeter capable of directly measuring instantaneous velocities is described. The new LDV uses a novel detection technique based on the utilization of a static slightly defocused spherical Fabry-Perot interferometer used in conjunction with a special mask for the detection of instantaneous Doppler frequency shifts. The essential characteristics of this LDV are discussed, and such a system recently developed is described. Results of turbulent flow measurements show good agreement with data obtained using hot wire anemometry.

  7. Quantitative Doppler ultrasound evaluation of occlusive arterial disease in the lower limb

    DEFF Research Database (Denmark)

    Bagi, P; Sillesen, H; Hansen, H J

    1988-01-01

    duration of PRT was used for comparison with ankle/brachial pressure index (A/B index) and angiography. A highly significant correlation was found between PRT and A/B index (r = -0.75, P less than 0.001). Based on receiver operating characteristic curves an overall diagnostic accuracy of 90% in diagnosing......Forty consecutive patients with lower limb arterial disease were evaluated using a multi-gated pulsed Doppler system. Doppler signals were sampled at 4 sites in each limb, and following spectral analysis, the pulse rise time (PRT) was measured. The value obtained at the location giving the longest...

  8. Doppler lidar atmospheric wind sensors - A comparative performance evaluation for global measurement applications from earth orbit

    Science.gov (United States)

    Menzies, R. T.

    1986-01-01

    A comparison is made of four prominent Doppler lidar systems, ranging in wavelength from the near UV to the middle IR, which are presently being studied for their potential in an earth-orbiting global tropospheric wind field measurement application. The comparison is restricted to relative photon efficiencies, i.e., the required number of transmitted photons per pulse is calculated for each system for midtropospheric velocity estimate uncertainties ranging from + or - 1 to + or - 4 m/s. The results are converted to laser transmitter pulse energy and power requirements. The analysis indicates that a coherent CO2 Doppler lidar operating at 9.11-micron wavelength is the most efficient.

  9. Enhanced optical precursors by Doppler effect via active Raman gain process.

    Science.gov (United States)

    Peng, Yandong; Niu, Yueping; Zhang, Lida; Yang, Aihong; Jiang, Lin; Gong, Shangqing

    2012-08-15

    A scheme for enhancing precursor pulse by Doppler effect is proposed in a room-temperature active-Raman-gain medium. Due to abnormal dispersion between two gain peaks, main fields are advanced and constructively interfere with optical precursors, which leads to enhancement of the transient pulse at the rise edge of the input. Moreover, after Doppler averaging, the abnormal dispersion intensifies and the constructive interference between precursors and main fields is much strengthened, which boosts the transient spike. Simulation results demonstrate that the peak intensity of precursors could be enhanced nearly 20 times larger than that of the input.

  10. The US color Doppler in acute renal failure.

    Science.gov (United States)

    Nori, G; Granata, A; Leonardi, G; Sicurezza, E; Spata, C

    2004-12-01

    Imaging techniques, especially ultrasonography and Doppler, can give an effective assistance in the differential diagnosis of acute renal failure (ARF). An resistance Index (RI) value >0.75 is reported as optimal in attempting differential diagnosis between acute tubular necrosis (ANT) and prerenal ARF. In hepatorenal syndrome (HRS) RIs is very increased. In some renal vasculitis, as nodose panarteritis (PN), hemolytic-uremic syndrome (HUS), thrombotic thrombocytopenic purpura (TTP), parenchymal perfusion is reduced and RI increased. In lupus nephritis the RI values are correlated with creatinine level and normal RI are considered as a good prognostic tool. In acute primitive or secondary glomerulonephritis (GN), RI value is normal, with diffuse parenchymal hypervascularization. In acute crescentic and proliferative GN and tubulo-interstitial disease, color Doppler (CD) and power Doppler (PD) reveal a decreased renal parenchymal perfusion, which correlates with increased RI values. In acute thrombosis of renal artery, US color Doppler (DUS) reveals either an absence of Doppler signal or a tardus-parvus pulse distal to the vascular obstruction. In this situation it is possible to visualize hyperthropic perforating vessels that redirect their flow from the capsular plexus to the renal parenchyma. In acute thrombosis of the renal vein Doppler analysis of parenchymal vessels reveals remarkable RI values, sometimes with reversed diastolic flow. In postrenal ARF an adjunct to the differentiation between obstruction and non obstructive dilatation can be found through RIs. Diagnostic criteria of obstruction as reported by literature are: RI>0.70 in the obstructed kidney and, mostly, a difference in RI between the 2 kidneys >0.06-0.1.

  11. Serial Doppler echocardiographic assessment of left and right ventricular performance after a first myocardial infarction

    DEFF Research Database (Denmark)

    Møller, J E; Søndergaard, E; Poulsen, S H

    2001-01-01

    We sought to investigate the relation between left ventricular (LV) and right ventricular (RV) function assessed with the Doppler-derived myocardial performance index (MPI), to assess serial changes, and to investigate the prognostic value of biventricular assessment of cardiac function after...... a first myocardial infarction (MI). To do so, serial Doppler echocardiography was performed in 77 consecutive patients with a first MI. Right ventricular MPI correlated significantly with LV MPI (r = 0.51, P ....59 +/- 0.18 versus 0.44 +/- 0.19, P =.001), whereas no difference in LV MPI was seen (0.55 +/- 0.19 versus 0.56 +/- 0.13, P = not significant). Right ventricular MPI showed a rapid normalization during follow-up, whereas LV MPI did not decrease. During follow-up, 23 patients died of cardiac causes or were...

  12. Doppler echocardiographic evaluation of HIV-positive patients in different stages of the disease

    Directory of Open Access Journals (Sweden)

    Werneck Guilherme Lobosco

    1999-01-01

    Full Text Available OBJETIVE: To evaluate by Doppler echocardiography (DE early abnormalities of ventricular function in HIV-positive patients, as well as other cardiac abnormalities that can be detected by this method, with special emphasis on mitral valve flow. METHODS: 84 HIV- positive patients, 59 with CD4 cell count >500/mm³ (Group A and 25 with CD4 cell count 500/mm³ had no abnormalities by DE. Patients with a more advanced infection (those with a CD4 cell count <500/mm³, had a significantly abnormal LV systolic function and a higher incidence of pericardial effusion and mitral regurgitation. Mitral valve inflow by Doppler did not indicate diastolic dysfunction.

  13. Clinical assessment of transthoracic echocardiography skills: a generalizability study

    DEFF Research Database (Denmark)

    Nielsen, Dorte Guldbrand; O'Neill, Lotte; Jensen, Signe

    2015-01-01

    Context: Transthoracic echocardiography (TTE) is a widely used cardiac imaging technique that all cardiologists should be able to perform competently. Traditionally, TTE competence has been assessed by unstructured observation or in test situations separated from daily clinical practice. An objec...

  14. Intra-cardiac echocardiography in alcohol septal ablation

    DEFF Research Database (Denmark)

    Cooper, Robert M; Shahzad, Adeel; Newton, James;

    2015-01-01

    Alcohol septal ablation (ASA) in hypertrophic obstructive cardiomyopathy reduces left ventricular outflow tract gradients. A third of patients do not respond; inaccurate localisation of the iatrogenic infarct can be responsible. Transthoracic echocardiography (TTE) using myocardial contrast can b...

  15. Speckle tracking echocardiography in acute lupus myocarditis: comparison to conventional echocardiography

    Directory of Open Access Journals (Sweden)

    Riëtte Du Toit

    2017-07-01

    Full Text Available Aims: Lupus myocarditis occurs in 5–10% of patients with systemic lupus erythematosus (SLE. No single feature is diagnostic of lupus myocarditis. Speckle tracking echocardiography (STE can detect subclinical left ventricular dysfunction in SLE patients, with limited research on its utility in clinical lupus myocarditis. We report on STE in comparison to conventional echocardiography in patients with clinical lupus myocarditis. Methods and results: A retrospective study was done at a tertiary referral hospital in South Africa. SLE patients with lupus myocarditis were included and compared to healthy controls. Echocardiographic images were reanalyzed, including global longitudinal strain through STE. A poor echocardiographic outcome was defined as final left ventricular ejection fraction (LVEF <40%. 28 SLE patients fulfilled the criteria. Global longitudinal strain correlated with global (LVEF: r = −0.808; P = 0.001 and regional (wall motion score: r = 0.715; P < 0.001 function. In patients presenting with a LVEF ≥50%, global longitudinal strain (P = 0.023, wall motion score (P = 0.005 and diastolic function (P = 0.004 were significantly impaired vs controls. Following treatment, LVEF (35–47% (P = 0.023 and wall motion score (1.88–1.5 (P = 0.017 improved but not global longitudinal strain. Initial LVEF (34%; P = 0.046 and global longitudinal strain (−9.5%; P = 0.095 were lower in patients with a final LVEF <40%. Conclusions: This is the first known report on STE in a series of patients with clinical lupus myocarditis. Global longitudinal strain correlated with regional and global left ventricular function. Global longitudinal strain, wall motion score and diastolic parameters may be more sensitive markers of lupus myocarditis in patients presenting with a preserved LVEF ≥50%. A poor initial LVEF and global longitudinal strain were associated with a persistent LVEF <40%. Echocardiography is a non-invasive tool with diagnostic and

  16. Avoiding transthoracic echocardiography and transesophageal echocardiography for patients with variable body mass indexes in infective endocarditis

    Directory of Open Access Journals (Sweden)

    Robert Sogomonian

    2016-04-01

    Full Text Available Background: Echocardiography has been a popular modality used to aid in the diagnosis of infective endocarditis (IE with the modified Duke criteria. We evaluated the necessity between the uses of either a transthoracic echocardiography (TTE or transesophageal echocardiography (TEE in patients with a body mass index (BMI greater than or equal to 25 kg/m2 and less than 25 kg/m2. Methods: A single-centered, retrospective study of 198 patients between 2005 and 2012 diagnosed with IE based on modified Duke criteria. Patients, required to be above age 18, had undergone an echocardiogram study and had blood cultures to be included in the study. Results: Among 198 patients, two echocardiographic groups were evaluated as 158 patients obtained a TTE, 143 obtained a TEE, and 103 overlapped with TEE and TTE. Out of these patients, 167 patients were included in the study as 109 (65% were discovered to have native valve vegetations on TEE and 58 (35% with TTE. TTE findings were compared with TEE results for true negatives and positives to isolate valvular vegetations. Overall sensitivity of TTE was calculated to be 67% with a specificity of 93%. Patients were further divided into two groups with the first group having a BMI ≥25 kg/m2 and the subsequent group with a BMI <25 kg/m2. Patients with a BMI ≥25 kg/m2 who underwent a TTE study had a sensitivity and specificity of 54 and 92%, respectively. On the contrary, patients with a BMI < 25 kg/m2 had a TTE sensitivity and specificity of 78 and 95%, respectively. Conclusions: Patients with a BMI <25 kg/m2 and a negative TTE should refrain from further diagnostic studies, with TEE strong clinical judgment is warranted. Patients with a BMI ≥ 25 kg/m2 may proceed directly to TEE as the initial study, possibly avoiding an additional study with a TTE.

  17. Dobutamine stress echocardiography in healthy adult male rats

    OpenAIRE

    Couet Jacques; Roussel Élise; Drolet Marie-Claude; Lachance Dominic; Plante Eric; Arsenault Marie

    2005-01-01

    Abstract Background Dobutamine stress echocardiography is used to investigate a wide variety of heart diseases in humans. Dobutamine stress echocardiography has also been used in animal models of heart disease despite the facts that the normal response of healthy rat hearts to this type of pharmacological stress testing is unknown. This study was performed to assess this normal response. Methods 15 normal adult male Wistar rats were evaluated. Increasing doses of dobutamine were infused intra...

  18. Minimally invasive cardiac surgery and transesophageal echocardiography

    Directory of Open Access Journals (Sweden)

    Ajay Kumar Jha

    2014-01-01

    Full Text Available Improved cosmetic appearance, reduced pain and duration of post-operative stay have intensified the popularity of minimally invasive cardiac surgery (MICS; however, the increased risk of stroke remains a concern. In conventional cardiac surgery, surgeons can visualize and feel the cardiac structures directly, which is not possible with MICS. Transesophageal echocardiography (TEE is essential during MICS in detecting problems that require immediate correction. Comprehensive evaluation of the cardiac structures and function helps in the confirmation of not only the definitive diagnosis, but also the success of surgical treatment. Venous and aortic cannulations are not under the direct vision of the surgeon and appropriate positioning of the cannulae is not possible during MICS without the aid of TEE. Intra-operative TEE helps in the navigation of the guide wire and correct placement of the cannulae and allows real-time assessment of valvular pathologies, ventricular filling, ventricular function, intracardiac air, weaning from cardiopulmonary bypass and adequacy of the surgical procedure. Early detection of perioperative complications by TEE potentially enhances the post-operative outcome of patients managed with MICS.

  19. Transoesophageal echocardiography: What a neuroanaesthesiologist should know?

    Directory of Open Access Journals (Sweden)

    Minati Choudhury

    2015-01-01

    Full Text Available Transoesophageal echocardiography (TEE is a semi invasive imaging modality rapidly gained credence and popularity in the cardiothoracic centers worldwide by mid 1990s. It has also been found to be useful in some noncardiac surgical procedures, in particular in the management of neurosurgical patients and haemodynamically unstable patients in intensive care units (ICUs. The principal goal of basic transoesophageal echocardiographic examination encompass a broad range of anatomic imaging including the diagnosis of air embolism, causes of haemodynamic instability, ventricular size and function, volume status, and complications from invasive procedures, as well as the clinical impact or etiology of pulmonary dysfunction in ICU. TEE is relatively cheap and semi-invasive, but it should not be used as a stand-alone device but as a tool which provides data in addition to the data acquired from other forms of monitoring. The establishment of TEE in perioperative neuro anaesthetic care though recent, may result in a significant change in the role of the anaesthetsiologist who, using TEE can provide new information which may change the course and the outcome of surgical procedures.

  20. Dynamic 3D echocardiography in virtual reality

    Directory of Open Access Journals (Sweden)

    Simoons Maarten L

    2005-12-01

    Full Text Available Abstract Background This pilot study was performed to evaluate whether virtual reality is applicable for three-dimensional echocardiography and if three-dimensional echocardiographic 'holograms' have the potential to become a clinically useful tool. Methods Three-dimensional echocardiographic data sets from 2 normal subjects and from 4 patients with a mitral valve pathological condition were included in the study. The three-dimensional data sets were acquired with the Philips Sonos 7500 echo-system and transferred to the BARCO (Barco N.V., Kortrijk, Belgium I-space. Ten independent observers assessed the 6 three-dimensional data sets with and without mitral valve pathology. After 10 minutes' instruction in the I-Space, all of the observers could use the virtual pointer that is necessary to create cut planes in the hologram. Results The 10 independent observers correctly assessed the normal and pathological mitral valve in the holograms (analysis time approximately 10 minutes. Conclusion this report shows that dynamic holographic imaging of three-dimensional echocardiographic data is feasible. However, the applicability and use-fullness of this technology in clinical practice is still limited.

  1. Alterations in left ventricular structure and diastolic function in professional football players: assessment by tissue Doppler imaging and left ventricular flow propagation velocity.

    Science.gov (United States)

    Tumuklu, M Murat; Ildizli, Muge; Ceyhan, Koksal; Cinar, Cahide Soydas

    2007-02-01

    Long-term regular exercise is associated with physiologic and morphologic cardiac alterations. Tissue Doppler imaging (TDI) and ventricular early flow propagation velocity (Vp) are new tolls in the evaluation of myocardial function. We sought to compare TDI and Vp findings in professional football players and age-adjusted sedentary controls to assess the effect of regular athletic training on myocardial function. Twenty-four professional football players and age-, sex-, and weight-adjusted 20 control subjects underwent standard Doppler echocardiography pulsed TDI, performed parasternal four-chamber views by placing sample volume septal and lateral side of mitral annulus and lateral tricuspid annulus. Vp values were obtained by measuring the slope delineated by first aliasing velocity from the mitral tips toward the apex by using apical four-chamber color M-mode Doppler images. Age, body surface area, blood pressure, and heart rate were comparable between two groups. Football players had significantly increased LV mass, mass index (due to both higher wall thickness and end-diastolic diameter), end-systolic and end-diastolic volume, left atrial diameter, and decreased transmitral diastolic late velocity. In athletes TDI analysis showed significantly increased mitral annulus septal DTI peak early diastolic (e) velocity (0.22 +/- 0.04 vs 0.19 +/- 0.04, P velocity (0.19 +/- 0.03 vs 0.16 +/- 0.02, P velocity ratio (1.96 +/- 0.41 and 1.66 +/- 0.23, P velocity (E) to e in both lateral (4.72 +/- 1.20 vs 5.95 +/- 1.38, P = 0.007) and septal (3.90 +/- 0.80 vs 5.25 +/- 1.50, P = 0.002) side of mitral annulus were significantly lower in athletes. In Vp evaluation, we found higher Vp values (60.52 +/- 6.95 in athletes and 56.56 +/- 4.24 in controls, P = 0.03) in football players. Professional football playing is associated with morphologic alteration in left ventricle and left atrium and improvement in left ventricle diastolic function that can be detected by TDI and Vp. These

  2. Robust population transfer in atomic beams induced by Doppler shifts

    Science.gov (United States)

    Unanyan, R. G.

    2016-10-01

    The influence of photon momentum recoil on adiabatic population transfer in an atomic three-level lambda system is studied. It is shown that the Doppler frequency shifts, due to atomic motion, can play an important role in adiabatic population transfer processes of atomic internal states by a pair of laser fields. For the limiting case of slow atoms (Doppler shift much smaller than the photon recoil energy), the atoms occupy the same target state regardless of the order of switching of laser fields, while for the case of fast atoms interacting with the intuitive sequence of pulses, the target state is the intermediate atomic state. Furthermore, it is shown that this novel technique for adiabatic population transfer is related to a level crossing in the bright-intermediate state basis (rather than in the original atomic basis). It is shown that these processes are robust with respect to parameter fluctuations, such as the laser pulse area and the relative spatial offset (delay) of the laser beams. The obtained results can be used for the control of temporal evolution of atomic populations in cold atomic beams by externally adjustable Doppler shifts.

  3. Planetary Doppler Imaging

    Science.gov (United States)

    Murphy, N.; Jefferies, S.; Hart, M.; Hubbard, W. B.; Showman, A. P.; Hernandez, G.; Rudd, L.

    2014-12-01

    Determining the internal structure of the solar system's gas and ice giant planets is key to understanding their formation and evolution (Hubbard et al., 1999, 2002, Guillot 2005), and in turn the formation and evolution of the solar system. While internal structure can be constrained theoretically, measurements of internal density distributions are needed to uncover the details of the deep interior where significant ambiguities exist. To date the interiors of giant planets have been probed by measuring gravitational moments using spacecraft passing close to, or in orbit around the planet. Gravity measurements are effective in determining structure in the outer envelope of a planet, and also probing dynamics (e.g. the Cassini and Juno missions), but are less effective in probing deep structure or the presence of discrete boundaries. A promising technique for overcoming this limitation is planetary seismology (analogous to helioseismology in the solar case), postulated by Vorontsov, 1976. Using trapped pressure waves to probe giant planet interiors allows insight into the density and temperature distribution (via the sound speed) down to the planetary core, and is also sensitive to sharp boundaries, for example at the molecular to metallic hydrogen transition or at the core-envelope interface. Detecting such boundaries is not only important in understanding the overall structure of the planet, but also has implications for our understanding of the basic properties of matter at extreme pressures. Recent Doppler measurements of Jupiter by Gaulme et al (2011) claimed a promising detection of trapped oscillations, while Hedman and Nicholson (2013) have shown that trapped waves in Saturn cause detectable perturbations in Saturn's C ring. Both these papers have fueled interest in using seismology as a tool for studying the solar system's giant planets. To fully exploit planetary seismology as a tool for understanding giant planet structure, measurements need to be made

  4. THE ROLE OF ECHOCARDIOGRAPHY IN THE DIFFERENTIAL DIAGNOSIS BETWEEN TRAINING INDUCED MYOCARDIAL HYPERTROPHY VERSUS CARDIOMYOPATHY

    Directory of Open Access Journals (Sweden)

    Tomas Venckunas

    2007-06-01

    Full Text Available Increased myocardial mass due to regular high-volume intense exercise training (so-called athlete's heart is not uncommon. Although directly correlated with the extent of training loads, myocardial hypertrophy is not present exclusively in well-trained or elite athletes. Athlete's heart is considered a physiological phenomenon with no known harmful consequences. However, extreme forms of myocardial hypertrophy due to endurance training resemble a structural heart disease such as hypertrophic cardiomyopathy, a condition associated with substantially increased risk of cardiac event. Endurance sports such as rowing and road cycling, rather than strength/power training, are most commonly associated with left ventricular (LV wall thickness compatible with hypertrophic cardiomyopathy. The differentiation between physiological and maladaptive cardiac hypertrophy in athletes is undoubtedly important, since untreated cardiac abnormality often possesses a real threat of premature death due to heart failure during intense physical exertion. Luckily, the distinction from pathological hypertrophy is usually straightforward using transthoracic echocardiography, as endurance athletes, in addition to moderately and proportionally thickened LV walls with normal acoustic density, tend to possess increased LV diameter. In more uncertain cases, a detailed evaluation of myocardial function using (tissue Doppler and contrast echocardiography is effective. When a doubt still remains, knowledge of an athlete's working capacity may be useful in evaluating whether the insidious cardiac pathology is absent. In such cases cardiopulmonary exercise testing typically resolves the dilemma: indices of aerobic capacity are markedly higher in healthy endurance athletes compared to patients. Other characteristics such as a decrease of LV mass due to training cessation are also discussed in the article

  5. Role of Transesophageal Echocardiography in the Diagnosis of Paradoxical Low Flow, Low Gradient Severe Aortic Stenosis

    Science.gov (United States)

    Abudiab, Muaz M.; Pandit, Anil

    2017-01-01

    Background and Objectives Prior studies indicate that up to 35% of cases of severe aortic stenosis (AS) have paradoxical low flow, low gradient despite preserved left ventricular ejection fraction (LVEF). However, error in left ventricular outflow tract (LVOT) diameter may lead to misclassification. Herein, we determined whether measurement of LVOT diameter by transesophageal echocardiography (TEE) results in reclassification of cases to non-severe AS. Subjects and Methods Patients with severe AS with aortic valve area (AVA) <1 cm2 by transthoracic echocardiography (TTE) within 6 months were studied. Paradoxical low flow, low gradient was defined as mean Doppler gradient (MG) <40 mm Hg and stroke volume index (SVI) ≤35 mL/m2. Preserved LVEF was defined as ≥0.50. Results Among 108 patients, 12 (15%) had paradoxical low flow, low gradient severe AS despite preserved LVEF based on TTE measurement. When LVOT diameter by TEE in 2D was used, only 5 (6.3%) patients had low flow, low gradient severe AS (p<0.001). Coefficients of variability for intraobserver and interobserver measurement of LVOT were <10%. However, the limits of agreement between TTE and TEE measurement of LVOT ranged from 0.43 cm (95% confidence interval [CI]: 0.36 to 0.5) to -0.31 cm (95% CI: -0.38 to -0.23). Conclusion TEE measured LVOT diameter may result in reclassification to moderate AS in some patients due to low prevalence of true paradoxical low flow, low gradient (PLFLG) severe AS.

  6. Cardiac Characterization of sgca-Null Mice Using High Resolution Echocardiography.

    Science.gov (United States)

    Fayssoil, Abdallah; Renault, Gilles; Guerchet, Nicolas; Marchiol-Fournigault, Carmen; Fougerousse, Françoise; Richard, Isabelle

    2013-01-01

    Limb-girdle muscular dystrophy 2D (LGMD2D) is an inherited myogenic disorder belonging to the group of muscular dystrophies. Sgca-null mouse is a knock-out model of LGMD2D. Little is known about cardiac phenotype characterization in this model at different ages. We conducted a prospective study to characterize cardiac sgca-null mice phenotype using high resolution Doppler echocardiography at different ages. Conventional echocardiography was performed on anesthetised mice using a Vevo 770 (Visualsonics) with 30 MHz cardiac probe. Wild Type (WT) and sgca-null mice were scanned at 13, 15 and 17 months. From M-mode, we measured interventricular septal (IVS) wall thickness, posterior wall (PW) thickness, and end-left ventricular diameter in systolic and diastolic. From the above parameters, we calculated left ventricular (LV) shortening fraction (SF), LV ejection fraction (EF) and LV mass. At age 13 months, PW diastolic thickness was increased in sgca-null mice (0.89±0.14 mm vs 0.73±0.2 mm; P=0.020) and LV mass was higher in sgca-null mice (LV mass 205.2 mg vs 143 mg; P=0.001). We found also dilation of the LV (LVEDD: 4.84 mm vs 4.29 mm; P=0.019) in sgca-null mice. At age 15 months, dilation of the LV (LVEDD: 4.86 mm vs 4 mm; P=0.05) with an increase of the LV mass (165.7 mg vs 127.12; P=0.03) are found in sgca-null mice. At age 17 months, we found a decrease of the PW thickening (17% vs 30%; P=0.036). This work provides echocardiographic insights for the assessment of pharmaceutical therapies in sgca-null mice.

  7. Echocardiography and passive leg raising in the postoperative period: A prospective observational study.

    Science.gov (United States)

    El Hadouti, Yasser; Valencia, Lucía; Becerra, Angel; Rodríguez-Pérez, Aurelio; Vincent, Jean L

    2017-07-15

    Signs of hypovolaemia are frequent in the postoperative period, but not all patients need or respond to fluid administration. An increase in cardiac output (CO) after passive leg raising (PLR) has been demonstrated to be useful as a volume response predictor in non-surgical, spontaneously breathing patients. The objective of this study was to evaluate the accuracy of transthoracic echocardiography after PLR to predict fluid responsiveness in post-surgical patients. A prospective observational study. A tertiary hospital between January and July 2015. Fifty-one spontaneously breathing postoperative patients with suspected hypovolaemia (arterial hypotension, oliguria, tachycardia or delayed capillary refill) were considered for the study. Demographic and personal data were collected, as well as heart rate variations, mean arterial pressure during PLR and after administering 500 ml of Ringer's lactate solution. CO was measured by transthoracic echocardiography. The primary outcome was measurement of CO before and after PLR and Ringer's lactate administration. Forty-one patients were included in the study (six patients were excluded because of a poor echocardiographic window and four because of misalignment of the Doppler and outflow tract of the left ventricle). Twenty-two patients (54%) were considered responders to fluid therapy, with an increase of stroke volume greater than or equal to 15% after 500 ml lactated Ringer's infusion. The highest area under the curve was found for an increase in CO (0.91 ± 0.05; 95% confidence interval 0.78 to 0.97). An increase in CO greater than 11% after the PLR manoeuvre predicts a volume response with 68% sensitivity and 100% specificity. This is the first study showing that measurement of CO after PLR can predict volume response in spontaneously breathing postoperative patients.

  8. FETAL ECHOCARDIOGRAPHY: A STUDY OF CLINICAL OUTCOME

    Directory of Open Access Journals (Sweden)

    Rajanish

    2014-01-01

    Full Text Available BACKGROUND : S tructural abnormalities of the heart and great vessels are fairly common congenital lab normalities with the incidenceof8 in 1000 live births. With the advent of real time scanners fetal cardia can atomy can be analyze d echocardiographically. The earlier diagnosis will make an impact on clinical management of fetus with congenital heart disease. It helps intimely triage and optimal management of specific congenital heart disease either structural , functional orarrhythmia . OBJECTIVES : This study was conducted to note the spectrum of congenital heart diseases detected on fetal echo in pregnant mothers referred with high risk for CHD sand to assess the outcome of prenatally detected congenital heart diseases. MATERIAL S AND METHODS : T he study is aprospective descriptive study conducted in a tertiary care pediatric hospital in Mumbai over period of one year . P regnant mothers were referred for fetal echo , where pregnancy was considered as high risk for CHDs due to maternal , fetalfactorsorabnormallevel 1 scan.Fetal echowas performed by a trained pediatric cardiologistat 18 to 20 week of gestation using HP sonos 2000 echocardiographicmachinewith3/3.5 Hz transducer. Cardiac lesionsandoutcome of pregnancy was noted by postnatal follow - up of patients. RESULTS : A total of 170 patients underwent fetal echo , 13 patients have not delivered and 48 were lost to follow - up. Fetal echo was normal in 130(76.4% and abnormalities were detected in 40(23.5%.Structural anomalies were seen in 24(14.1% , arrhythmia in 5(2.9% and functional abnormalities in 11(6.4%.On outcome analysis84 (77.1% arealive , IUD /terminationof pregnancyoccurred in 18(16.5% , neonatal death in 6 (5.5% , infant death in 1 (0.9%. CONCLUSIONS : All ranges of CHDs can be diagnosed by fetal echocardiography . O utcome of prenatally detected complex congenital heart disease is poor ; nonetheless earlier detection provides a n opportunity for early interventions and

  9. Digital tele-echocardiography: a look inside

    Directory of Open Access Journals (Sweden)

    Daniele Giansanti

    2009-12-01

    Full Text Available Digital tele-echocardiography (T-E has the potentiality to allow relevant change in health care organization. The purpose of the paper is to analyze the scientific development around the digital T-E to explore the successful applications and individuate the limits which hamper the routine introduction in the National Health Care System (NHCS. A literature review was carried out by searching for studies from 1988 to 2008. The studies have been investigated according to four crucial issues: a the employment of the digital T-E versus the traditional videotape registrations; b the evolution of the telecommunication network and T-E; c the quality assessment of the images after transmission; d the economical legal and social impact of the T-E. The analysis showed a generalized increased diffusion of the digital T-E thanks to the wonderful development of the information technology. This diffusion was sometimes also accompanied by investigation studies on the diagnostic accuracy and on cost-benefit analysis with special care to the economical and social impact. The study examined some points which need to be improved to allow a better introduction of the T-E in the NHCS as a routine exam. Among these two were the most important. The first was the lacking of an easy and automatic methodology for the image quality assessment alternative to the currently used methods which are highly complex, expensive and needing a long time to be applied. The second was the lacking of a properly designed methodology for the health technology assessment in T-E, the latter, as it is well known is a very complex and heterogeneus system embedding parts from telematics, bioengineering, and medical physics.

  10. Digital tele-echocardiography: a look inside.

    Science.gov (United States)

    Giansanti, Daniele; Morelli, Sandra

    2009-01-01

    Digital tele-echocardiography (T-E) has the potentiality to allow relevant change in health care organization. The purpose of the paper is to analyze the scientific development around the digital T-E to explore the successful applications and individuate the limits which hamper the routine introduction in the National Health Care System (NHCS). A literature review was carried out by searching for studies from 1988 to 2008. The studies have been investigated according to four crucial issues: a) the employment of the digital T-E versus the traditional videotape registrations; b) the evolution of the telecommunication network and T-E; c) the quality assessment of the images after transmission; d) the economical legal and social impact of the T-E. The analysis showed a generalized increased diffusion of the digital T-E thanks to the wonderful development of the information technology. This diffusion was sometimes also accompanied by investigation studies on the diagnostic accuracy and on cost-benefit analysis with special care to the economical and social impact. The study examined some points which need to be improved to allow a better introduction of the T-E in the NHCS as a routine exam. Among these two were the most important. The first was the lacking of an easy and automatic methodology for the image quality assessment alternative to the currently used methods which are highly complex, expensive and needing a long time to be applied. The second was the lacking of a properly designed methodology for the health technology assessment in T-E, the latter, as it is well known is a very complex and heterogeneous system embedding parts from telematics, bioengineering, and medical physics.

  11. High Frequency Color Doppler Image of Choroidal Detachment

    Institute of Scientific and Technical Information of China (English)

    Jinghong Wu; Lijuan Zou; Zhongyao Wu; Lixun Cheng

    2000-01-01

    Purpose: To study the Color Doppler Image (CDI) characteristics of choroidal detachment and the applied value of CDI.Methods: Seventy-two cases (74 eyes) of choroidal detachment were studied retrospectively.Results: The typical ultragraph of chroridal detachment displayed one or several smooth hemispherical or lobuler circular thick bands, with convex side toward vitreous cavity. Most of the choroidal detachments were located before the equator, a few of them were beyond the equator. CDI displayed blood flow singnal in the band. Pulse Doppler showed the frequency spectrum features of retinal detachment band were similar to those of central retinal vessels, whereas the frequency spectum features of choroidal detachment bend resembled those of ciliary artery in some cases of retinal detachment (RD) accompanied by choroidal detachment.Conclusion: CDI could make a correct and precise diagnosis of choroidal detachment.Eye Science 2000; 16. 61 ~ 64.

  12. Aircraft Wake Vortex Measurement with Coherent Doppler Lidar

    Science.gov (United States)

    Wu, Songhua; Liu, Bingyi; Liu, Jintao

    2016-06-01

    Aircraft vortices are generated by the lift-producing surfaces of the aircraft. The variability of near-surface conditions can change the drop rate and cause the cell of the wake vortex to twist and contort unpredictably. The pulsed Coherent Doppler Lidar Detection and Ranging is an indispensable access to real aircraft vortices behavior which transmitting a laser beam and detecting the radiation backscattered by atmospheric aerosol particles. Experiments for Coherent Doppler Lidar measurement of aircraft wake vortices has been successfully carried out at the Beijing Capital International Airport (BCIA). In this paper, the authors discuss the Lidar system, the observation modes carried out in the measurements at BCIA and the characteristics of vortices.

  13. Aircraft Wake Vortex Measurement with Coherent Doppler Lidar

    Directory of Open Access Journals (Sweden)

    Wu Songhua

    2016-01-01

    Full Text Available Aircraft vortices are generated by the lift-producing surfaces of the aircraft. The variability of near-surface conditions can change the drop rate and cause the cell of the wake vortex to twist and contort unpredictably. The pulsed Coherent Doppler Lidar Detection and Ranging is an indispensable access to real aircraft vortices behavior which transmitting a laser beam and detecting the radiation backscattered by atmospheric aerosol particles. Experiments for Coherent Doppler Lidar measurement of aircraft wake vortices has been successfully carried out at the Beijing Capital International Airport (BCIA. In this paper, the authors discuss the Lidar system, the observation modes carried out in the measurements at BCIA and the characteristics of vortices.

  14. Method of target tracking with Doppler blind zone constraint

    Institute of Scientific and Technical Information of China (English)

    Wei Han; Ziyue Tang; Zhenbo Zhu

    2013-01-01

    Doppler blind zone (DBZ) has a bad influence on the airborne early warning radar, although it has good detection per-formance for low altitude targets with pulse Doppler (PD) techno-logy. In target tracking, the blind zone can cause target tracking breakage easily. In order to solve this problem, a paral el parti-cle filter (PF) algorithm based on multi-hypothesis motion models (MHMMs) is proposed. The algorithm produces multiple possible target motion models according to the DBZ constraint. Particles are updated with the constraint in each motion model. Once the first measurement from the target which reappears from DBZ fal s into the particle cloud formed by any model, the measurement-track association succeeds and track breakage is avoided. The simulation results show that on the condition of different DBZ ranges, a high association ratio can be got for targets with different maneuverability levels, which accordingly improves the tracking quality.

  15. Estimation of physiological sub-millimeter displacement with CW Doppler radar.

    Science.gov (United States)

    Jia Xu; Xiaomeng Gao; Padasdao, Bryson E; Boric-Lubecke, Olga

    2015-01-01

    Doppler radar physiological sensing has been studied for non-contact detection of vital signs including respiratory and heartbeat rates. This paper presents the first micrometer resolution Wi-Fi band Doppler radar for sub-millimeter physiological displacement measurement. A continuous-wave Doppler radar working at 2.4GHz is used for the measurement. It is intended for estimating small displacements on the body surface resulting from physiological activity. A mechanical mover was used as target, and programmed to conduct sinusoidal motions to simulate pulse motions. Measured displacements were compared with a reference system, which indicates a superior performance in accuracy for having absolute errors less than 10μm, and relative errors below 4%. It indicates the feasibility of highly accurate non-contact monitoring of physiological movements using Doppler radar.

  16. Doppler peaks from active perturbations

    CERN Document Server

    Magueijo, J; Coulson, D; Ferreira, P; Magueijo, Joao; Albrecht, Andreas; Coulson, David; Ferreira, Pedro

    1995-01-01

    We examine how the qualitative structure of the Doppler peaks in the angular power spectrum of the cosmic microwave anisotropy depends on the fundamental nature of the perturbations which produced them. The formalism of Hu and Sugiyama is extended to treat models with cosmic defects. We discuss how perturbations can be ``active'' or ``passive'' and ``incoherent'' or ``coherent'', and show how causality and scale invariance play rather different roles in these various cases. We find that the existence of secondary Doppler peaks and the rough placing of the primary peak unambiguously reflect these basic properties.

  17. Inverse Doppler Effects in Flute

    CERN Document Server

    Zhao, Xiao P; Liu, Song; Shen, Fang L; Li, Lin L; Luo, Chun R

    2015-01-01

    Here we report the observation of the inverse Doppler effects in a flute. It is experimentally verified that, when there is a relative movement between the source and the observer, the inverse Doppler effect could be detected for all seven pitches of a musical scale produced by a flute. Higher tone is associated with a greater shift in frequency. The effect of the inverse frequency shift may provide new insights into why the flute, with its euphonious tone, has been popular for thousands of years in Asia and Europe.

  18. Experimental verification of color flow imaging based on wideband Doppler method.

    Science.gov (United States)

    Tanaka, Naohiko

    2014-01-01

    The purpose of this study is to eliminate the aliasing in color flow imaging. The wideband Doppler method is applied to generate a color flow image, and the validity of the method is experimentally confirmed. The single beam experiment is carried out to confirm the velocity estimation based on the wideband Doppler method. The echo data for the conventional pulsed Doppler method and the wideband Doppler method are obtained using a flow model, and the estimated velocity for each method is compared. The color flow images for each method are also generated using several types of flow model. The generated images are compared, and the characteristics of the imaging based on the wideband Doppler method are discussed. The high velocity beyond the Nyquist limit is successfully estimated by the wideband Doppler method, and the availability in low velocity estimation is also confirmed. The aliasing in color flow images is eliminated, and the generated images show the significance of the elimination of the aliasing in the flow imaging. The aliasing in color flow imaging can be eliminated by the wideband Doppler method. This technique is useful for the exact understanding of blood flow dynamics.

  19. Doppler tomography in fusion plasmas and astrophysics

    CERN Document Server

    Salewski, Mirko; Heidbrink, Bill; Jacobsen, Asger Schou; Korsholm, Soren Bang; Leipold, Frank; Madsen, Jens; Moseev, Dmitry; Nielsen, Stefan Kragh; Rasmussen, Jesper; Stagner, Luke; Steeghs, Danny; Stejner, Morten; Tardini, Giovani; Weiland, Markus

    2015-01-01

    Doppler tomography is a well-known method in astrophysics to image the accretion flow, often in the shape of thin discs, in compact binary stars. As accretion discs rotate, all emitted line radiation is Doppler-shifted. In fast-ion D-alpha (FIDA) spectroscopy measurements in magnetically confined plasma, the D-alpha-photons are likewise Doppler-shifted ultimately due to gyration of the fast ions. In either case, spectra of Doppler-shifted line emission are sensitive to the velocity distribution of the emitters. Astrophysical Doppler tomography has lead to images of accretion discs of binaries revealing bright spots, spiral structures, and flow patterns. Fusion plasma Doppler tomography has lead to an image of the fast-ion velocity distribution function in the tokamak ASDEX Upgrade. This image matched numerical simulations very well. Here we discuss achievements of the Doppler tomography approach, its promise and limits, analogies and differences in astrophysical and fusion plasma Doppler tomography, and what ...

  20. Doppler Ultrasound: What Is It Used for?

    Science.gov (United States)

    ... in your neck (carotid artery stenosis) A Doppler ultrasound can estimate how fast blood flows by measuring the rate of change in its pitch (frequency). During a Doppler ultrasound, a technician trained in ultrasound imaging (sonographer) presses ...

  1. Biventricular diastolic function assessed by Doppler echocardiogram in children vertically infected with human immunodeficiency virus

    Directory of Open Access Journals (Sweden)

    Mauricio L. Silva

    2014-07-01

    Full Text Available OBJECTIVE: to determine, by Doppler-echocardiography, the frequency of cardiac diastolic dysfunction in asymptomatic and clinically stable pediatric patients with vertical infection by the human immunodeficiency virus (HIV, from the cardiovascular viewpoint. METHODS: this was an observational, prospective, and cross-sectional study, performed at a regional referral clinic for patients with HIV, in a convenience sample of 94 individuals, assessing biventricular diastolic function by Doppler-echocardiography, and weight, blood hemoglobin, and percentage of lymphocytes T-CD4+. RESULTS: fifty patients had diastolic dysfunction. Left ventricular dysfunction occurred in 38.7%, and the predominant type of dysfunction was decreased myocardial compliance. Right ventricular dysfunction was observed in 29.4% of the sample, and abnormal relaxation was the most prevalent type. Simultaneous biventricular dysfunction occurred in 14.1% of the individuals. There was no association between dysfunction and the immune status. CONCLUSIONS: diastolic dysfunction occurred, individually or simultaneously, with no association with immune status; decreased myocardial compliance was predominant in the left ventricle, and abnormal relaxation in the right ventricle.

  2. Doppler echocardiographic study in adolescents and young adults with sickle cell anemia

    Directory of Open Access Journals (Sweden)

    Wolney de Andrade Martins

    1999-12-01

    Full Text Available OBJECTIVE: Anatomical and functional assessment of the heart through Doppler and echocardiography in patients with cell anemia (SCA. METHODS: Twenty-five patients with SCA and ages ranging from 14 to 45 years were prospectively studied in a comparison with 25 healthy volunteers. All of them underwent clinical and laboratory evaluation and Doppler echocardiography as well.The measurements were converted into body surface indices. RESULTS: There were increases in all chamber diameters and left ventricle (LV mass of the SCA patients. It was characterised an eccentric hypertrophy of the left ventricle. The preload was increased (left ventricle end-diastolic volume and the afterload was decreased (diastolic blood pressure, peripheral vascular resistance and end-systolic parietal stress ESPS. The cardiac index was increased due to the stroke volume. The ejection fraction and the percentage of the systolic shortening , as well as the systolic time intervals of the LV were equivalent. The isovolumetric contraction period of the LV was increased. The mitral E-septum distance and the end-systolic volume index (ESVi were increased. The ESPS/ESVi ratio,a loading independent parameter, was decreased in SCA, suggesting systolic dysfunction. No significant differences in the diastolic function or in the pulmonary pressure occurred. CONCLUSION: Chamber dilations, eccentric hypertrophy and systolic dysfunction confirm the evidence of the literature in characterizing a sickle cell anemia cardiomyopathy.

  3. CALF BLOOD-FLOW AND POSTURE - DOPPLER ULTRASOUND MEASUREMENTS DURING AND AFTER EXERCISE

    NARCIS (Netherlands)

    VANLEEUWEN, BE; BARENDSEN, GJ; LUBBERS, J; DEPATER, L

    1992-01-01

    To investigate the joint effects of body posture and calf muscle pump, the calf blood flow of eight healthy volunteers was measured with pulsed Doppler equipment during and after 3 min of rhythmic exercise on a calf ergometer in the supine, sitting, and standing postures. Muscle contractions serious

  4. Doppler Properties of Polyphase Coded Pulse Compression Waveforms.

    Science.gov (United States)

    1982-09-30

    phase structure. An example is shown in Fig. 12 for a PI code. Each code can be generated or compressed with the same standard FFT phase filter shown...in Fig. 13. The phase shifts used before and after the FFT phase filter depend on the particular code. One way to reduce the 4-dB cyclic variation of...could be achieved by the use of additional phase shifters and delay lines in the F, output ports of the FFT phase filter shown in Fig. 12. EXPANSION r r

  5. High-frequency Ultrasound Doppler System for Biomedical Applications with a 30 MHz Linear Array

    Science.gov (United States)

    Xu, Xiaochen; Sun, Lei; Cannata, Jonathan M.; Yen, Jesse T.; Shung, K. Kirk

    2008-01-01

    In this paper, we report the development of the first high-frequency (HF) pulsed-wave Doppler system using a 30 MHz linear array transducer to assess the cardiovascular functions in small animal. This array based pulsed-wave Doppler system included a 16-channel HF analog beamformer, a HF pulsed-wave Doppler module, timing circuits, HF bipolar pulsers, and analog front-ends. The beamformed echoes acquired by the 16 channel analog beamformer, were directly fed to the HF pulsed-wave Doppler module. Then the in-phase and quadrature-phase (IQ) audio Doppler signals were digitized by either a sound card or a Gage digitizer and stored in a PC. The Doppler spectrogram was displayed on a PC in real time. The two-way beam-widths were determined to be 160 μm to 320 μm when the array was electronically focused at different focal points at depths from 5–10 mm. A micro flow phantom, consisting of a polyimide tube with inner diameter of 127 μm, and the wire phantom were used to evaluate and calibrate the system. The results show that the system is capable of detecting motion velocity of the wire phantom as low as 0.1 mm/s, and detecting blood-mimicking flow velocity in the 127 μm tube lower than 7 mm/s. The system was subsequently used to measure the blood flow in vivo in two mouse abdominal superficial vessels with diameters of approximately 200 μm, and a mouse aorta close to the heart. These results demonstrated that this system may become an indispensable part of the current HF array based imaging systems for small animal studies. PMID:17993243

  6. The myocardial performance index during low-dose dobutamine echocardiography in control subjects and patients with a recent myocardial infarction

    DEFF Research Database (Denmark)

    Nørager, Betina; Husic, Mirza; Møller, Jacob E

    2004-01-01

    BACKGROUND: Wall-motion analysis during low-dose dobutamine echocardiography (LDDE) is a semiquantitative measure of left ventricular contractile reserve after myocardial infarction (MI). The Doppler echocardiographic myocardial performance index (MPI) is a quantitative measure of combined left...... ventricular systolic and diastolic function. We sought to characterize the changes in MPI during LDDE in control subjects and patients with MI, and to describe the relation of these changes to changes in regional systolic function. METHODS: MPI was obtained at rest and during LDDE (10 microg/kg/min) in 25......MPI was defined as the change from rest to LDDE. RESULTS: MPI decreased significantly during LDDE in groups 1 and 2A, whereas MPI increased in group 2B (DeltaMPI = 0.12 +/- 0.04 and 0.10 +/- 0.08 vs -0.03 +/- 0.08, P index predicted DeltaMPI (beta = 0...

  7. Study on characteristics of chirp about Doppler wind lidar system

    Science.gov (United States)

    Du, Li-fang; Yang, Guo-tao; Wang, Ji-hong; Yue, Chuan; Chen, Lin-xiang

    2016-11-01

    In the doppler wind lidar, usually every 4MHz frequency error will produce wind error of 1m/s of 532nm laser. In the Doppler lidar system, frequency stabilization was achieved through absorption of iodine molecules. Commands that control the instrumental system were based on the PID algorithm and coded using VB language. The frequency of the seed laser was locked to iodine molecular absorption line 1109 which is close to the upper edge of the absorption range, with long-time (>4h) frequency-locking accuracy being≤0.5MHz and long-time frequency stability being 10-9 . The experimental result indicated that the seed frequency and the pulse laser frequency have a deviation, which effect is called the laser chirp characteristics. Finally chirp test system was constructed and tested the frequency offset in time. And such frequency deviation is known as Chirp of the laser pulse. The real-time measured frequency difference of the continuous and pulsed lights was about 10MHz, long-time stability deviation was around 5MHz. After experimental testing technology mature, which can monitoring the signal at long-term with corrected the wind speed.

  8. Modeling of Doppler frequency shift in multipath radiochannels

    Science.gov (United States)

    Penzin, Maksim; Iyin, Nikolay

    2016-06-01

    We discuss the modeling of propagation of a quasi-monochromatic radio signal, represented by a coherent pulse sequence, in a non-stationary multipath radio channel. In such a channel, signal propagation results in the observed frequency shift for each ray (Doppler effect). The modeling is based on the assumption that during propagation of a single pulse a channel can be considered stationary. A phase change in the channel transfer function is shown to cause the observed frequency shift in the received signal. Thus, instead of measuring the Doppler frequency shift, we can measure the rate of change in the mean phase of one pulse relative to another. The modeling is carried out within the framework of the method of normal waves. The method enables us to model the dynamics of the electromagnetic field at a given point with the required accuracy. The modeling reveals that a local change in ionospheric conditions more severely affects the rays whose reflection region is in the area where the changes occur.

  9. Estimation of circumferential fiber shortening velocity by echocardiography.

    Science.gov (United States)

    Ruschhaupt, D G; Sodt, P C; Hutcheon, N A; Arcilla, R A

    1983-07-01

    The M-mode and two-dimensional echocardiograms of 40 young patients were analyzed to compare the mean circumferential fiber shortening velocity (Vcf) of the left ventricle calculated separately by two methods. The mean circumferential fiber shortening velocity was derived from the M-mode echocardiogram as minor axis shortening/ejection time and derived from the two-dimensional echocardiogram as actual circumference change/ejection time. With computer assistance, circumference was determined from the short-axis two-dimensional echocardiographic images during end-diastole and end-systole. Good correlations were obtained between the left ventricular diameter derived by M-mode echocardiography and the vertical axis during end-diastole (r = 0.79) and end-systole (r = 0.88) derived by two-dimensional echocardiography. Likewise, high correlations were noted between diameter and circumference in end-diastole (r = 0.89) and end-systole (r = 0.88). However, comparison of Vcf obtained by M-mode echocardiography with that obtained by two-dimensional echocardiography showed only fair correlation (r = 0.68). Moreover, the diameter/circumference ratio determined in end-diastole and end-systole differed significantly (p less than 0.001), possibly owing to the change in geometry of the ventricular sector image during systole. Although Vcf derived by M-mode echocardiography is a useful index of left ventricular performance, it does not truly reflect the circumference change during systole.

  10. Application of echocardiography in resynchronization treatment of heart failure patients

    Institute of Scientific and Technical Information of China (English)

    DAI Hai-long; GUANG Xue-feng; XIAO Zhi-cheng; ZHANG Ming

    2012-01-01

    Objective To review the updated research progress about the application of echocardiography in resynchronization treatment of chronic heart failure patients.Data sources The data used in this review were from PubMed,published in English and using the key terms "heart failure","echocardiography" and "cardiac resynchronization therapy".Study selection Relevant articles were reviewed and selected to address the stated purpose.Results Increasing numbers of studies have suggested the importance of echocardiography in resynchronization treatment of chronic heart failure patients.Echocardiography can evaluate atrioventricular,inter- and intra-ventricular mechanical dyssynchrony before cardiac resynchronization therapy (CRT),as a guidance to assess the optimal left ventricular (LV) pacing location,optimize the atrioventricular and interventricular delays and predict response to CRT.Conclusions Echocardiography is both non invasive and easily repeatable,and plays a crucial role in appraisal of heart synchronism,instruction of actuator placement,optimization of the device procedure,and prediction of the response to CRT.Chin Med J 2012; 125(19):3548-3555

  11. What every radiologist should know about paediatric echocardiography

    Energy Technology Data Exchange (ETDEWEB)

    Sorantin, Erich, E-mail: erich.sorantin@medunigraz.at [Division of Pediatric Radiology, Department of Radiology, Medical University Graz, Auenbruggerplatz 34, A-8036 Graz (Austria); Heinzl, Bernd [Division of Pediatric Cardiology, Department of Pediatric and Adolescent Medicine, Medical University Graz, Auenbruggerplatz 34, A-8036 Graz (Austria)

    2014-09-15

    Congenital heart defects (CHD) occur in less than one percent of all newborns. Echocardiography represents the imaging modality of choice for morphological and functional assessment. In childhood the different CHD types can be diagnosed trustfully and can be performed bedside. In the follow-up of CHD cross sectional imaging plays an important role and therefore it is essential for the radiologist to know the features, challenges and limitations of echocardiography. Within this review article a systematic approach for morphological and functional assessment of the heart will is given along with representative example images. In addition, typical echocardiographic findings in common CHD is presented. In older children, adolescents and grown-ups with CHD (GUCH) echocardiography suffers from limitations – partially due to skeletal deformations and lung emphysema. In particular right ventricular function assessment is not always possible by echocardiography. Therefore strengths and limitations of echocardiography will be discussed the role of cardiac magnetic resonance imaging (cMRI) and cardiac computed tomography (cCT) emphasized.

  12. Speckles in laser doppler perfusion imaging

    NARCIS (Netherlands)

    Rajan, Vinayakrishnan

    2007-01-01

    Laser Doppler Flowmetry (LDF) is a noninvasive diagnostic method to measure blood flow in tissue [1]. The technique is based on measuring the Doppler shift induced by moving red blood cells to the illuminating coherent light. A laser Doppler instrument often gives output signals related to the flux,

  13. Micro-Doppler Analysis of Small UAVs

    NARCIS (Netherlands)

    Wit, J.J.M. de; Harmanny, R.I.A.; Prémel Cabic, G.

    2012-01-01

    Coherent radar measures micro-Doppler properties of moving objects. The micro-Doppler signature depends on parts of an object moving and rotating in addition to the main body motion (e.g. rotor blades) and is therefore characteristic for the type of object. In this study, the micro-Doppler signature

  14. Micro-Doppler Analysis of Small UAVs

    NARCIS (Netherlands)

    Wit, J.J.M. de; Harmanny, R.I.A.; Prémel Cabic, G.

    2012-01-01

    Coherent radar measures micro-Doppler properties of moving objects. The micro-Doppler signature depends on parts of an object moving and rotating in addition to the main body motion (e.g. rotor blades) and is therefore characteristic for the type of object. In this study, the micro-Doppler signature

  15. The Doppler Effect--A New Approach

    Science.gov (United States)

    Allen, J.

    1973-01-01

    Discusses the Doppler effect as it applies to different situations, such as a stationary source of sound with the observer moving, a stationary observer, and the sound source and observer both moving. Police radar, satellite surveillance radar, radar astronomy, and the Doppler navigator, are discussed as applications of Doppler shift. (JR)

  16. Electrocardiography and echocardiography in athletic heart imagining

    Directory of Open Access Journals (Sweden)

    D Biały

    2003-03-01

    Full Text Available The aim of the study was evaluation of electrocardiographic and echocardiographic parameters in athletes. „Athletic heart” characteristics were compared with fit persons’ heart. 96 athletes participated in the study. Sportsmen were divided into: static (S, dynamic (D and composite (SD exercise groups and Polish (I, European (II, World (III champions. 30 students from Sport Academy formed the control group (K. Electrocardiographic and echocardiographic examination were performed in everyone. As regards the type of exercise, the end-systolic left ventricular (LV dimension was smaller in S in comparison with D and SD (28.9 vs 32.2 and 32.68 mm; P<0.05. LV mass was bigger in D in comparison with K (273.2 vs 218.6 g; P<0.05. Medium Pulmonary Artery Pressure (MPAP in S and SD was lower in respect to D and K (11.75; 11.08 vs 15.52; 17.43 mm Hg; P<0.05. We observed lower heart rate in D, SD in comparison with K (58.64; 60.54 vs 68.8; P<0.05, bigger R wave amplitude in V5 (RV5 (21.65; 23.5 vs 15.03 mm; P<0.05 and V6 (RV6 (23.5 vs 15.3 mm; P<0.05 in group S in respect to K. LV mass was bigger in III than in K (261.3 vs 218.6 g; P<0.05. MPAP was lower in I and II in comparison with K (11.42; 13.13 vs 17.43 mmHg; P<0.05. HR was lower in categories I, II than in K (61.32; 60.13 vs 68.8; P<0.05, RV5 was bigger in I in comparison with K (19.5 vs 15.03 mm; P<0.05. The electrocardiography and echocardiography proves to find some significant differences between athletic and fit persons’ heart especially as concerns MPAP, RV5, RV6 values.

  17. The Incidence of Patent Foramen Ovale in 1,000 Consecutive Patients: A Contrast Transesophageal Echocardiography Study

    Science.gov (United States)

    Fisher, Daniel C.; Fisher, Edward A.; Budd, Jacqueline H.; Rosen, Stacey E.; Goldman, Martin E.

    1995-01-01

    Study objective: Patent foramen ovale (PFO) is present in 10 to 35% of people and has been reported to be an important risk factor for cardioembolic cerebrovascular accidents (CVAs) and transient ischemic attacks (TIAS), especially in younger patients. While contrast transthoracic echocardiography has been used to detect PFO, contrast transesophageal echocardiography (TEE) has a greater sensitivity. Prior studies reported the incidence of PFO in patients presenting with a CVA or TIA. Design: To determine the incidence of PFO in a more general population, we reviewed 1,000 consecutive TEES performed with contrast and color Doppler for the presence of PFO and other cardioembolic risk factors, including atrial septal aneurysm (ASA), aortic plaque, atrial fibrillation (AFib), and atrial thrombi. While imaging with monoplane or biplane TEE, multiple injections of agitated saline solution were injected during cough or Valsalva maneuver to detect flow through a PFO. Patients: There were 482 male and 518 female patients with mean age of 60 + 17 years (range 11 to 93 years). Results: Patent foramen ovale was found in 9.2% of all patients and, though seen in all age groups divided by decade, the incidence in patients aged 40 to 49 years was greater than those aged 70 to 79 years (12.96% vs 6.15%',, p=0.03). Contrast TEE had a much higher detection rate than color Doppler alone. Importantly, there was no greater incidence of PFO in patients with CVA vs thos without CVA, or in male vs female patients. Also, there was a very strong correlation between the presence of ASA and PFO (p<.001). Conclusion: Thus, PFO detected by TEE, frequently seen with ASA, is seen in all age groups and does not in itself present a risk factor for CVA. The association of PFO with peripheral thrombosis and CVA needs further study.

  18. The Incidence of Patent Foramen Ovale in 1,000 Consecutive Patients: A Contrast Transesophageal Echocardiography Study

    Science.gov (United States)

    Fisher, Daniel C.; Fisher, Edward A.; Budd, Jacqueline H.; Rosen, Stacey E.; Goldman, Martin E.

    1995-01-01

    Study objective: Patent foramen ovale (PFO) is present in 10 to 35% of people and has been reported to be an important risk factor for cardioembolic cerebrovascular accidents (CVAs) and transient ischemic attacks (TIAS), especially in younger patients. While contrast transthoracic echocardiography has been used to detect PFO, contrast transesophageal echocardiography (TEE) has a greater sensitivity. Prior studies reported the incidence of PFO in patients presenting with a CVA or TIA. Design: To determine the incidence of PFO in a more general population, we reviewed 1,000 consecutive TEES performed with contrast and color Doppler for the presence of PFO and other cardioembolic risk factors, including atrial septal aneurysm (ASA), aortic plaque, atrial fibrillation (AFib), and atrial thrombi. While imaging with monoplane or biplane TEE, multiple injections of agitated saline solution were injected during cough or Valsalva maneuver to detect flow through a PFO. Patients: There were 482 male and 518 female patients with mean age of 60 + 17 years (range 11 to 93 years). Results: Patent foramen ovale was found in 9.2% of all patients and, though seen in all age groups divided by decade, the incidence in patients aged 40 to 49 years was greater than those aged 70 to 79 years (12.96% vs 6.15%',, p=0.03). Contrast TEE had a much higher detection rate than color Doppler alone. Importantly, there was no greater incidence of PFO in patients with CVA vs thos without CVA, or in male vs female patients. Also, there was a very strong correlation between the presence of ASA and PFO (pCVA. The association of PFO with peripheral thrombosis and CVA needs further study.

  19. Echocardiography and invasive hemodynamics during stress testing for diagnosis of heart failure with preserved ejection fraction: an experimental study.

    Science.gov (United States)

    Leite, Sara; Oliveira-Pinto, José; Tavares-Silva, Marta; Abdellatif, Mahmoud; Fontoura, Dulce; Falcão-Pires, Inês; Leite-Moreira, Adelino F; Lourenço, André P

    2015-06-15

    Inclusion of exercise testing in diagnostic guidelines for heart failure with preserved ejection fraction (HFpEF) has been advocated, but the target population, technical challenges, and underlying pathophysiological complexity raise difficulties to implementation. Hemodynamic stress tests may be feasible alternatives. Our aim was to test Trendelenburg positioning, phenylephrine, and dobutamine in the ZSF1 obese rat model to find echocardiographic surrogates for end-diastolic pressure (EDP) elevation and HFpEF. Seventeen-week-old Wistar-Kyoto, ZSF1 lean, and obese rats (n = 7 each) randomly and sequentially underwent (crossover) Trendelenburg (30°), 5 μg·Kg(-1)·min(-1) dobutamine, and 7.5 μg·Kg(-1)·min(-1) phenylephrine with simultaneous left ventricular (LV) pressure-volume loop and echocardiography evaluation under halogenate anesthesia. Effort testing with maximum O2 consumption (V̇o 2 max) determination was performed 1 wk later. Obese ZSF1 showed lower effort tolerance and V̇o 2 max along with higher resting EDP. Both Trendelenburg and phenylephrine increased EDP, whereas dobutamine decreased it. Significant correlations were found between EDP and 1) peak early filling Doppler velocity of transmitral flow (E) to corresponding myocardial tissue Doppler velocity (E') ratio, 2) E to E-wave deceleration time (E/DT) ratio, and 3) left atrial area (LAA). Diagnostic efficiency of E/DT*LAA by receiver-operating characteristic curve analysis for elevation of EDP above a cut-off of 13 mmHg during hemodynamic stress was high (area under curve, AUC = 0.95) but not higher than that of E/E' (AUC = 0.77, P = 0.15). Results in ZSF1 obese rats suggest that noninvasive echocardiography after hemodynamic stress induced by phenylephrine or Trendelenburg can enhance diagnosis of stable HFpEF and constitute an alternative to effort testing.

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

    Science.gov (United States)

    Obata, Yurie; Mizogami, Maki; Nyhan, Daniel; Berkowitz, Dan E; Steppan, Jochen; Barodka, Viachaslau

    2017-01-01

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

  1. Qualification Testing of Laser Diode Pump Arrays for a Space-Based 2-micron Coherent Doppler Lidar

    Science.gov (United States)

    Amzajerdian, Farzin; Meadows, Byron L.; Baker, Nathaniel R.; Barnes, Bruce W.; Singh, Upendra N.; Kavaya, Michael J.

    2007-01-01

    The 2-micron thulium and holmium-based lasers being considered as the transmitter source for space-based coherent Doppler lidar require high power laser diode pump arrays operating in a long pulse regime of about 1 msec. Operating laser diode arrays over such long pulses drastically impact their useful lifetime due to the excessive localized heating and substantial pulse-to-pulse thermal cycling of their active regions. This paper describes the long pulse performance of laser diode arrays and their critical thermal characteristics. A viable approach is then offered that allows for determining the optimum operational parameters leading to the maximum attainable lifetime.

  2. Hand-carried ultrasound performed at bedside in cardiology inpatient setting – a comparative study with comprehensive echocardiography

    Directory of Open Access Journals (Sweden)

    Ramires Jose F

    2004-11-01

    Full Text Available Abstract Background Hand-carried ultrasound (HCU devices have been demonstrated to improve the diagnosis of cardiac diseases over physical examination, and have the potential to broaden the versatility in ultrasound application. The role of these devices in the assessment of hospitalized patients is not completely established. In this study we sought to perform a direct comparison between bedside evaluation using HCU and comprehensive echocardiography (CE, in cardiology inpatient setting. Methods We studied 44 consecutive patients (mean age 54 ± 18 years, 25 men who underwent bedside echocardiography using HCU and CE. HCU was performed by a cardiologist with level-2 training in the performance and interpretation of echocardiography, using two-dimensional imaging, color Doppler, and simple calliper measurements. CE was performed by an experienced echocardiographer (level-3 training and considered as the gold standard. Results There were no significant differences in cardiac chamber dimensions and left ventricular ejection fraction determined by the two techniques. The agreement between HCU and CE for the detection of segmental wall motion abnormalities was 83% (Kappa = 0.58. There was good agreement for detecting significant mitral valve regurgitation (Kappa = 0.85, aortic regurgitation (kappa = 0.89, and tricuspid regurgitation (Kappa = 0.74. A complete evaluation of patients with stenotic and prosthetic dysfunctional valves, as well as pulmonary hypertension, was not possible using HCU due to its technical limitations in determining hemodynamic parameters. Conclusion Bedside evaluation using HCU is helpful for assessing cardiac chamber dimensions, left ventricular global and segmental function, and significant valvular regurgitation. However, it has limitations regarding hemodynamic assessment, an important issue in the cardiology inpatient setting.

  3. Myocardial contrast echocardiography (MCE) with triggered ultrasound does not cause premature ventricular complexes: evidence from PB127 MCE studies.

    Science.gov (United States)

    Raisinghani, Ajit; Wei, Kevin S; Crouse, Linda; Villanueva, Floredeliza; Feigenbaum, Harvey; Schiller, Nelson B; Weiss, James; Naqvi, Tasneem Z; Siegel, Robert; Monaghan, Mark; Goldman, Jonathan H; Demaria, Anthony

    2003-10-01

    Previous studies suggest that myocardial contrast echocardiography using high mechanical index triggered ultrasound can be associated with increased frequency of the premature ventricular complex (PVC). However, this association has not been systematically examined. PB127 (Point Biomedical Corp, San Carlos, Calif) is a novel microsphere designed for evaluation of myocardial perfusion with ultrasound. PB127 myocardial contrast echocardiography was performed with triggered harmonic power Doppler in early/mid diastole (mechanical index premature ventricular complex frequency at baseline, during, and after infusion of PB127 (dose premature ventricular complex were determined. PVC frequency did not increase with PB127 infusion in either cohort (P =.572, P =.263). Proportion of triggered intervals after QRS associated with PVC was similar to proportion of untriggered intervals in cohort A (P >.999) and was lower than untriggered intervals (P =.001) in B, suggesting that triggers do not cause PVC. PB127 does not cause increase PVC frequency during or after imaging with triggered ultrasound at mechanical index of 1.

  4. Does Left Ventricular Function on Echocardiography at Rest and Exercise Predict Recoarctation in Children with Postoperative Coarctation of Aorta ?

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    Taner Yavuz

    2011-12-01

    Full Text Available Objective: The aim of this study was to evaluate ventricular performance before and after exercise in children who had surgically repaired coarctation of aorta (CoA by using two dimensional, M- mode and Doppler echocardiography and to determine whether this method can be used for identifying recoarctation in comparison to Magnetic Resonance Imaging (MRI. Design: We studied on 24 patients who were operated for CoA previously and compared with 24 healthy controls. Blood pressure monitoring, echocardiographies at rest and after exercise and MRI of aortic arc were performed. Patients having had ≥ 30 % of isthmic stenosis on MRI was diagnosed as recoarctation. The patient group were divided as Group A (patient without recoarctation and Group B (patients with recoarctation and were compared. Results: We found that 8 of 24 patients had recoarctation on MRI. Physical examination and echocardiographic evaluation revealed that hypertension on the right arm at rest, systolic and diastolic hypotension on the left leg after exercise, increased values of ejection fraction, fractioned shortening and aortic gradient on exercise may predict more than 30 % narrowing of the aortic isthmus. Conclusion: These findings can be useful as predictors for recoarctation.

  5. Technology update: intracardiac echocardiography – a review of the literature

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    Vitulano N

    2015-05-01

    Full Text Available Nicola Vitulano, Vincenzo Pazzano, Gemma Pelargonio, Maria Lucia Narducci Institute of Cardiology, Department of Cardiovascular Sciences, Catholic University of the Sacred Heart, Rome, Italy Abstract: The development of new imaging tools helps in better investigation of cardiac structures and function by showing detailed images during interventional procedures. Intracardiac echocardiography plays a pivotal role as an intraoperative real-time imaging tool during invasive cardiac procedures. Initially, this echocardiographic technique was particularly useful when transthoracic image quality was insufficient and to avoid general anesthesia for transesophageal imaging. Nowadays, intracardiac echocardiography is routinely used in several cardiac invasive laboratories to support several types of procedures, such as extraction and implantation of cardiac devices, electrophysiological mapping, ablation, and endomyocardial biopsies. This review gives an overview of the basic principles of intracardiac echocardiography and examines its applications in the different settings of invasive cardiology. Keywords: ICE, cardiovascular imaging, electrophysiology, invasive cardiology

  6. Recommendations for fetal echocardiography in twin pregnancy in 2016

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    Leszczyńska Katarzyna

    2016-01-01

    Full Text Available Progress in the fields of fetal cardiology and fetal surgery have been seen not only in singleton pregnancies but also in multiple pregnancies. Proper interpretation of prenatal echocardiography is critical to clinical decision making, family counseling and perinatal management for obstetricians, maternal fetal medicine specialists, neonatologists and pediatric cardiologists. Fetal echocardiography is one of the most challenging and time-consuming prenatal examinations to perform, especially in multiple gestations. Performing just the basic fetal exam in twin gestations may take an hour or more. Thus, it is not practical to perform this exam in all cases of multiple gestations. Therefore our review and recommendations are related to fetal echocardiography in twin gestation.

  7. Holographic laser Doppler imaging of pulsatile blood flow

    CERN Document Server

    Bencteux, Jeffrey; Kostas, Thomas; Bayat, Sam; Atlan, Michael

    2015-01-01

    We report on wide-field imaging of pulsatile motion induced by blood flow using heterodyne holographic interferometry on the thumb of a healthy volunteer, in real-time. Optical Doppler images were measured with green laser light by a frequency-shifted Mach-Zehnder interferometer in off-axis configuration. The recorded optical signal was linked to local instantaneous out-of-plane motion of the skin at velocities of a few hundreds of microns per second, and compared to blood pulse monitored by plethysmoraphy during an occlusion-reperfusion experiment.

  8. Pulse transit time differential measurement by fiber Bragg grating pulse recorder.

    Science.gov (United States)

    Umesh, Sharath; Padma, Srivani; Ambastha, Shikha; Kalegowda, Anand; Asokan, Sundarrajan

    2015-05-01

    The present study reports a noninvasive technique for the measurement of the pulse transit time differential (PTTD) from the pulse pressure waveforms obtained at the carotid artery and radial artery using fiber Bragg grating pulse recorders (FBGPR). PTTD is defined as the time difference between the arrivals of a pulse pressure waveform at the carotid and radial arterial sites. The PTTD is investigated as an indicator of variation in the systolic blood pressure. The results are validated against blood pressure variation obtained from a Mindray Patient Monitor. Furthermore, the pulse wave velocity computed from the obtained PTTD is compared with the pulse wave velocity obtained from the color Doppler ultrasound system and is found to be in good agreement. The major advantage of the PTTD measurement via FBGPRs is that the data acquisition system employed can simultaneously acquire pulse pressure waveforms from both FBGPRs placed at carotid and radial arterial sites with a single time scale, which eliminates time synchronization complexity.

  9. The Optimum Level of Sevoflurane in Pediatric Echocardiography.

    Science.gov (United States)

    Conghai, Fan; Fengchao, Zhang; Chengjing, Shan; Cheng, Wen; Yunji, Wang; Xiaobo, Li

    2015-11-01

    Sevoflurane is shown to be safe and effective in pediatric echocardiography. This study explores the optimum level in pediatric echocardiography. One hundred and twenty children, with an age range of 35 days-3 years, were included in this study. The children with severe cyanotic congenital heart disease or severe pneumonia, which was Grade I or II according to the American College of Physicians Guideline Grading, were excluded. All children received the anesthesia with sevoflurane. The inhalation anesthesia level decreased from 2.5 to 1.0 %, with a decrement of 0.5 %. The induction time (T0), echocardiography time (T1), and time to awakening (T2) in each child were recorded, and the changes in the blood pressure, heart rate, breath, and oxygen saturation in each child were also monitored. The Ramsay scale scoring during anesthesia and the case number of failure in echocardiography in each group were also recorded. When the level of sevoflurane inhalation was maintained at 1.0 %, the childrens' scores were low, including 8 incompliant children, and p sevoflurane inhalation level increased. When the sevoflurane inhalation increased to 1.5 %, the children could sleep with stable blood pressure, and no dysphoria occurred during the echocardiography. When the sevoflurane inhalation level increased to 2.5 %, the Ramsay scores did not increase. However, the T2 significantly increased (p blood pressure and heart rate in each group did not change significantly. With the premise of safety and efficacy in children, the optimum level of sevoflurane in pediatric echocardiography was 1.5-2.0 %.

  10. Evaluation of longitudinal myocardial deformation by 2-dimensional speckle-tracking echocardiography in heart transplant recipients: relation to coronary allograft vasculopathy.

    Science.gov (United States)

    Clemmensen, Tor Skibsted; Løgstrup, Brian Bridal; Eiskjær, Hans; Poulsen, Steen Hvitfeldt

    2015-02-01

    Coronary allograft vasculopathy (CAV) in heart transplant (HTx) recipients is characterized by diffuse affection of epicardial and intramyocardial coronary vessels. Despite significant CAV and anticipated affected myocardial function, left ventricular ejection fraction (LVEF) is often within the normal range, indicating the need of more sophisticated non-invasive methods to detect impaired myocardial function caused by CAV. Global longitudinal strain (GLS) represents a new echocardiographic measurement of systolic myocardial deformation. The aim of the study was to evaluate the relation between GLS measured by 2-dimensional speckle-tracking echocardiography and CAV in HTx patients. The study included 178 HTx patients and 20 healthy, age-matched individuals. All patients had an extensive echocardiographic evaluation and coronary angiography assessing CAV. CAV was classified according to International Society of Heart and Lung Transplantation classification (CAV0-3). CAV was seen in 38.8% of patients. Compared with controls (-20.6% ± 1.4%), GLS was significantly reduced according to the degree of CAV (CAV0, -16.7% ± 2.4%; CAV1, -15.2% ± 2.9%; CAV2-3, -14.0% ± 3.8%; controls, -20.6% ±1.4%; pTREND < 0.0001). In addition, we found decreasing peak systolic mitral annular velocities (pTREND = 0.0040), tissue-tracking values (pTREND = 0.0002), and LVEF according to CAV class (CAV0, 65.3% ± 5.4%; CAV2-3, 56.9% ± 11.7%; pTREND < 0.0001). The HTx population showed significant restrictive physiology compared with the control population, but no significant correlation was seen between CAV class and traditional diastolic parameters such as E/A ratio (pTREND = 0.38) or E-deceleration time (pTREND = 0.14). In contrast to LVEF and conventional pulsed mitral Doppler flow parameters used in the CAV classification, GLS relates to the presence and degree of CAV. The present results suggest GLS as a new method to be included in the monitoring of graft function in relation to CAV

  11. Doppler indicates of uterine artery Doppler velocimetry by placental location

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    Han, Sung Shik; Park, Yong Won; Cho, Jae Sung; Kwon, Hye Kyeung; Kim, Jae Wook [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2001-09-15

    Our purpose was to investigate the relation between the vascular resistance of uterine artery and placental location and to establish the reference value of Doppler index in uterine artery by placental location. Placental location and flow velocity waveforms of both uterine arteries in 7,016 pregnant women after 18 weeks gestation were examined using color Doppler ultrasonography. Placental location was classified as central and lateral placental and the uterine artery with lateral placental were divided into ipsilateral uterine artery (same side of the placental) and contralateral uterine artery (opposite side of the placenta). The uterine artery with central placental was classified as the central uterine artery. Systolic-Diastolic ratio (S/D ratio) of uterine arteries by gestational weeks were calculated and compared with the placental location and perinatal outcomes. In the lateral placental group, the S/D ratio of the contralateral uterine artery was higher than the ipsilateral one (mean=2.08+0.34 vs 1.89+0.34, p=0.0001). S/D ratio of the uterine artery decreased during second trimester and the ratio after 27 weeks was a tendency to have a constant values(ipsilateral: 1.85+ 0.34, central : 1.96+ 0.40, contralateral: 2.01+0.54). S/D ratio of the uterine artery was affected by placental location. So when we evaluate Doppler spectrum of uterine artery, placental location should be considered and we established the reference value of Doppler index of uterine artery by placental location.

  12. Acute right ventricular dysfunction: real-time management with echocardiography.

    Science.gov (United States)

    Krishnan, Sundar; Schmidt, Gregory A

    2015-03-01

    In critically ill patients, the right ventricle is susceptible to dysfunction due to increased afterload, decreased contractility, or alterations in preload. With the increased use of point-of-care ultrasonography and a decline in the use of pulmonary artery catheters, echocardiography can be the ideal tool for evaluation and to guide hemodynamic and respiratory therapy. We review the epidemiology of right ventricular failure in critically ill patients; echocardiographic parameters for evaluating the right ventricle; and the impact of mechanical ventilation, fluid therapy, and vasoactive infusions on the right ventricle. Finally, we summarize the principles of management in the context of right ventricular dysfunction and provide recommendations for echocardiography-guided management.

  13. Stress echocardiography in valvular heart disease: a current appraisal.

    Science.gov (United States)

    Naji, Peyman; Patel, Krishna; Griffin, Brian P; Desai, Milind Y

    2015-03-01

    Stress echocardiography is increasingly used in the management of patients with valvular heart disease and can aid in evaluation, risk stratification and clinical decision making in these patients. Evaluation of symptoms, exercise capacity and changes in blood pressure can be done during the exercise portion of the test, whereas echocardiographic portion can reveal changes in severity of disease, pulmonary artery pressure and left ventricular function in response to exercise. These parameters, which are not available at rest, can have diagnostic and prognostic importance. In this article, we will review the indications and diagnostic implications, prognostic implications, and clinical impact of stress echocardiography in decision making and management of patients with valvular heart disease.

  14. Role of Speckle Tracking Echocardiography in Dilated Cardiomyopathy: A Review

    Science.gov (United States)

    Virk, Hafeez Ul Hasan; Khalid, Muhammad; Rahman, Zia; Sitwala, Puja; Schoondyke, Jeffrey; Al-Balbissi, Kais

    2017-01-01

    Dilated cardiomyopathy (DCM) is an important cause of the heart failure. Timely diagnosis and optimal management decrease morbidity and mortality in heart failure patients. Although transthoracic echocardiography is used as the diagnostic test of choice in these patients, new modalities like speckle tracking echocardiography (STE) have promising results in diagnosing these patients in the earlier course of the disease. Advancements in cardiac imaging are expected as more clinical studies on the role of STE in different cardiac diseases that emerge. In this review article, we will discuss the basics of STE and its role in diagnosing DCM. PMID:28744419

  15. Azimuthal Doppler Effect in Optical Vortex Spectroscopy

    Science.gov (United States)

    Aramaki, Mitsutoshi; Yoshimura, Shinji; Toda, Yasunori; Morisaki, Tomohiro; Terasaka, Kenichiro; Tanaka, Masayoshi

    2015-11-01

    Optical vortices (OV) are a set of solutions of the paraxial Helmholtz equation in the cylindrical coordinates, and its wave front has a spiral shape. Since the Doppler shift is caused by the phase change by the movement in a wave field, the observer in the OV, which has the three-dimensional structured wave front, feels a three-dimensional Doppler effect. Since the multi-dimensional Doppler components are mixed into a single Doppler spectrum, development of a decomposition method is required. We performed a modified saturated absorption spectroscopy to separate the components. The OV and plane wave are used as a probe beam and pump beam, respectively. Although the plane-wave pump laser cancels the z-direction Doppler shift, the azimuthal Doppler shift remains in the saturated dip. The spatial variation of the dip width gives the information of the azimuthal Doppler shift. The some results of optical vortex spectroscopy will be presented.

  16. Quantifying pulmonary regurgitation and right ventricular function in surgically repaired tetralogy of Fallot: a comparative analysis of echocardiography and magnetic resonance imaging.

    Science.gov (United States)

    Mercer-Rosa, Laura; Yang, Wei; Kutty, Shelby; Rychik, Jack; Fogel, Mark; Goldmuntz, Elizabeth

    2012-09-01

    Patients with repaired tetralogy of Fallot are monitored for pulmonary regurgitation (PR) and right ventricular (RV) function. We sought to compare measures of PR and RV function on echocardiogram to those on cardiac magnetic resonance (CMR) and to develop a new tool for assessing PR by echocardiogram. Patients with repaired tetralogy of Fallot (n=143; 12.5±3.2 years) had an echocardiogram and CMR within 3 months of each other. On echocardiogram, RV function was assessed by (1) Doppler tissue imaging of the RV free wall and (2) myocardial performance index. The ratio of diastolic and systolic time-velocity integrals measured by Doppler of the main pulmonary artery was calculated. CMR variables included RV ejection fraction, RV volumes, and pulmonary regurgitant fraction (RF). Pulmonary regurgitation was graded as mild (RF40%). On CMR, RF was 34+17% and RV ejection fraction was 61+8%. Echocardiography had good sensitivity identifying cases with RF>20% (sensitivity 97%; 95% CI: 92-99%) but overestimated the amount of PR when RFPR in patients with repaired tetralogy of Fallot and warrants further investigation. However, echocardiography continues to have a limited ability to quantify PR and RV function as compared with CMR.

  17. The continuing challenge of evaluating diastolic function by echocardiography in children: developing concepts and newer modalities.

    Science.gov (United States)

    Mawad, Wadi; Friedberg, Mark K

    2017-01-01

    Assessment of diastolic function by echocardiography is challenging but important. Left ventricular filling has been more extensively studied than the right ventricle, and predominantly in adult populations. Although multiple parameters exist to assess diastolic function, they all have limitations, including load and heart rate dependency, which make assessment of diastolic function particularly challenging. The purpose of this article is to review evolving concepts and modalities for echo assessment of diastolic function in children. The paradigm whereby diastolic dysfunction severity progresses in a staged fashion from impaired relaxation to increasing ventricular stiffness, may not apply in children. In addition, previous adult guidelines are not readily applicable to children with cardiomyopathy and the applicability of the newly revised adult guidelines needs to be evaluated in children. It is unlikely that any one single echocardiographic diastolic parameter will adequately reflect diastolic function. Hence, parameters derived from atrioventricular valve inflow, pulmonary venous, and tissue Doppler need to be integrated. Newer modalities such as diastolic strain rate and rotation mechanics may be useful as more sensitive markers of early ventricular dysfunction but have important limitations and require more evaluation before routine use in practice. Assessment of systolic-diastolic coupling may enhance assessment of diastolic function. Diastolic function impacts outcomes and should be part of routine echocardiographic assessment of function. An integrative approach combining different parameters, possibly with contribution of newer modalities in the future, is required.

  18. Clinical utility of tissue Doppler imaging in patients with acute myocardial infarction complicated by cardiogenic shock

    Directory of Open Access Journals (Sweden)

    Zieroth Shelley

    2008-03-01

    Full Text Available Abstract Background Echocardiography is widely used in the management of patients with cardiogenic shock (CS. Left ventricular ejection fraction (EF has been shown to be an independent predictor of survival in CS. Tissue Doppler Imaging (TDI is a sensitive echocardiographic technique that allows for the early quantitative assessment of regional left ventricular dysfunction. TDI derived indices, including systolic velocity (S', early (E' and late (A' diastolic velocities of the lateral mitral annulus, are reduced in heart failure patients (EF Objective To characterize TDI derived indices in CS patients as compared to patients with chronic CHF. Methods Between 2006 and 2007, 100 patients were retrospectively evaluated who underwent echocardiography for assessment of LV systolic function. This population included: Group I 50 patients (30 males, 57 ± 13 years with chronic CHF as controls; and Group II 50 patients (29 males, 58 ± 10 years with CS. Spectral Doppler indices including peak early (E and late (A transmitral velocities, E/A ratio, and E-wave deceleration time were determined. Tissue Doppler indices including S', E' and A' velocities of the lateral annulus were measured. Results Of the entire cohort, the mean LVEF was 25 ± 5%. Cardiogenic shock patients demonstrated significantly lower lateral S', E' and a higher E/E' ratio (p Conclusion Despite similar reduction in LV systolic function, CS patients have reduced myocardial velocities and higher filling pressures using TDI, as compared to CHF patients. Whether TDI could be a reliable tool to determine CS patients with the best chance of recovery following revascularization is yet to be determined.

  19. Concepts and Tradeoffs in Velocity Estimation With Plane-Wave Contrast-Enhanced Doppler.

    Science.gov (United States)

    Tremblay-Darveau, Charles; Williams, Ross; Sheeran, Paul S; Milot, Laurent; Bruce, Matthew; Burns, Peter N

    2016-11-01

    While long Doppler ensembles are, in principle, beneficial for velocity estimates, short acoustic pulses must be used in microbubble contrast-enhanced (CE) Doppler to mitigate microbubble destruction. This introduces inherent tradeoffs in velocity estimates with autocorrelators, which are studied here. A model of the autocorrelation function adapted to the microbubble Doppler signal accounting for transit time, the echo frequency uncertainty, and contrast-agent destruction is derived and validated in vitro. It is further demonstrated that a local measurement of the center frequency of the microbubble echo is essential in order to avoid significant bias in velocity estimates arising from the linear and nonlinear frequency-dependent scattering of microbubbles and compensate for the inherent speckle nature of the received echo frequency. For these reasons, broadband Doppler estimators (2-D autocorrelator and Radon projection) are better suited than simpler narrow-band estimators (1-D autocorrelator and 1-D Fourier transform) for CE flow assessment. A case study of perfusion in a VX-2 carcinoma using CE plane-wave Doppler is also shown. We demonstrate that even when considering all uncertainties associated with microbubble-related decorrelation (destruction, pulse bandwidth, transit time, and flow gradient) and the need for real-time imaging, a coefficient of variation of 4% on the axial velocity is achievable with plane-wave imaging.

  20. Concepts and trade-offs in velocity estimation with plane-wave contrast-enhanced Doppler.

    Science.gov (United States)

    Tremblay-Darveau, Charles; Williams, Ross; Sheeran, Paul; Milot, Laurent; Bruce, Matthew; Burns, Peter

    2016-07-29

    While long Doppler ensembles are, in principle, beneficial for velocity estimates, short acoustic pulses must be used in microbubble contrast-enhanced Doppler to mitigate microbubble destruction. This introduces inherent trade-offs in velocity estimates with autocorrelators, which are studied here. A model of the autocorrelation function adapted to the microbubble Doppler signal, accounting for transit time, the echo frequency uncertainty and contrast-agent destruction is derived and validated in vitro. It is further demonstrated that a local measurement of the center frequency of the microbubble echo is essential in order to avoid significant bias in velocity estimates arising from the linear and nonlinear frequency-dependent scattering of microbubbles, and compensate the inherent speckle nature of the received echo frequency. For these reasons, broadband Doppler estimators (2D autocorrelator, Radon projection) are better suited than simpler narrowband estimators (1D autocorrelator, 1D Fourier transform) for contrast-enhanced flow assessment. A case study of perfusion in a VX-2 carcinoma using contrast-enhanced planewave Doppler is also shown. We demonstrate that even when considering all uncertainties associated with microbubble-related decorrelation (destruction, pulse bandwidth, transit time, flow gradient) and the need for real-time imaging, a coefficient of variation of 4% on the an axial velocity is achievable with planewave imaging.

  1. Exercise echocardiography in asymptomatic survivors of childhood cancer treated with anthracyclines

    DEFF Research Database (Denmark)

    Sieswerda, Elske; Kremer, Leontien C M; Vidmar, Suzanna

    2010-01-01

    BACKGROUND: Exercise echocardiography reveals abnormalities in asymptomatic childhood cancer survivors who previously have been treated with anthracyclines. We determined the added value of monitoring childhood cancer survivors with exercise echocardiography compared to monitoring with resting ec...

  2. Association of heart failure hospitalizations with combined electrocardiography and echocardiography criteria for left ventricular hypertrophy

    DEFF Research Database (Denmark)

    Gerdts, Eva; Okin, Peter M; Boman, Kurt

    2012-01-01

    The value of performing echocardiography in hypertensive patients with electrocardiographic left ventricular hypertrophy (LVH) is uncertain.......The value of performing echocardiography in hypertensive patients with electrocardiographic left ventricular hypertrophy (LVH) is uncertain....

  3. Birefringence effects of short probe pulses of electromagnetically induced transparency

    Science.gov (United States)

    Parshkov, Oleg M.; Kochetkova, Anastasia E.; Budyak, Victoria V.

    2016-04-01

    The numerical simulation results of radiations evolution in the presence of electromagnetically induced transparency for J=0-->J=1-->J=2 scheme of degenerate quantum transitions are presented. The pulse regime of wave interaction with Doppler broadening spectral lines was investigated. It was indicated that when the control field is linear polarized, the input circular polarized probe pulse breaks up in the medium into pulses with mutually perpendicular linear polarizations. Polarization direction of one of these pulses coincides with the polarization direction of control fields. The distance, which probe pulse passes in the medium to its full separation, decreases, when input probe pulse duration or control field intensity decreases. The input probe pulse intensity variation almost does not influence separation distance and speed of the linear polarized probe pulses in the medium. The effects, described above, may be interpreted as the birefringence effects of electromagnetically induced transparency in the case of short probe pulse.

  4. The Role of Focused Echocardiography in Pediatric Intensive Care: A Critical Appraisal

    Directory of Open Access Journals (Sweden)

    Heloisa Amaral Gaspar

    2015-01-01

    Full Text Available Echocardiography is a key tool for hemodynamic assessment in Intensive Care Units (ICU. Focused echocardiography performed by nonspecialist physicians has a limited scope, and the most relevant parameters assessed by focused echocardiography in Pediatric ICU are left ventricular systolic function, fluid responsiveness, cardiac tamponade and pulmonary hypertension. Proper ability building of pediatric emergency care physicians and intensivists to perform focused echocardiography is feasible and provides improved care of severely ill children and thus should be encouraged.

  5. Observing Molecular Spinning via the Rotational Doppler Effect

    CERN Document Server

    Korech, Omer; Gordon, Robert J; Averbukh, Ilya Sh; Prior, Yehiam

    2013-01-01

    When circularly polarized light is scattered from a rotating target, a rotational Doppler shift (RDS) emerges from an exchange of angular momentum between the spinning object and the electromagnetic field. Here, we used coherently spinning molecules to generate a shift of the frequency of a circularly polarized probe propagating through a gaseous sample. We used a linearly polarized laser pulse to align the molecules, followed by a second delayed pulse polarized at 45{\\deg} to achieve unidirectional molecular rotation. The measured RDS is orders of magnitude greater than previously observed by other methods. This experiment provides explicit evidence of unidirectional molecular rotation and paves the way for a new class of measurements in which the rotational direction of molecular reagents may be monitored or actively controlled.

  6. UWB micro-doppler radar for human gait analysis using joint range-time-frequency representation

    Science.gov (United States)

    Wang, Yazhou; Fathy, Aly E.

    2013-05-01

    In this paper, we present a novel, standalone ultra wideband (UWB) micro-Doppler radar sensor that goes beyond simple range or micro-Doppler detection to combined range-time-Doppler frequency analysis. Moreover, it can monitor more than one human object in both line-of-sight (LOS) and through wall scenarios, thus have full human objects tracking capabilities. The unique radar design is based on narrow pulse transceiver, high speed data acquisition module, and wideband antenna array. For advanced radar post-data processing, joint range-time-frequency representation has been performed. Characteristics of human walking activity have been analyzed using the radar sensor by precisely tracking the radar object and acquiring range-time-Doppler information simultaneously. The UWB micro-Doppler radar prototype is capable of detecting Doppler frequency range from -180 Hz to +180 Hz, which allows a maximum target velocity of 9 m/s. The developed radar sensor can also be extended for many other applications, such as respiration and heartbeat detection of trapped survivors under building debris.

  7. Development of quantitative Doppler indices for uteroplacental and fetal blood flow during the third trimester.

    Science.gov (United States)

    Joern, H; Funk, A; Goetz, M; Kuehlwein, H; Klein, A; Fendel, H

    1996-01-01

    The aim of our study was to describe the development of uteroplacental and fetal blood flow during the third trimester. Doppler examination was carried out on 393 uncomplicated pregnancies with uncomplicated term delivery. Using a pulsed color Doppler, we calculated the maximum systolic, mean and maximum end-diastolic velocity after correcting the angle of insonation. Patients under tocolysis or other medication influencing blood flow parameters were excluded from this cross-sectional study. Summarizing the results gained by Doppler ultrasound investigation of the uteroplacental and fetal blood vessels, we created quantiles as quantitative Doppler indices for the maximum systolic, mean (TAMX = time averaged maximum velocity) and maximum end-diastolic velocity. The following conclusions could be drawn: (1) resistance to the blood flow in the maternal portion of the placenta does not change during the third trimester; (2) resistance to the blood flow on the fetal side of the placenta decreases up to week 42 of gestation; (3) cerebral vascular resistance decreases constantly up to gestational week 42; and (4) vascular resistance to the blood flow of the kidney decreases only slightly during the third trimester. This study offers clinically important values for quantitative Doppler flow velocimetry for the first time. We hope that our findings improve the usefulness of Doppler ultrasound as a diagnostic tool in obstetrical management.

  8. Exercise stress echocardiography in patients with valvular heart disease.

    Science.gov (United States)

    Sharma, Vishal; Newby, David E; Stewart, Ralph A H; Lee, Mildred; Gabriel, Ruvin; Van Pelt, Niels; Kerr, Andrew J

    2015-09-01

    Stress echocardiography is recommended for the assessment of asymptomatic patients with severe valvular heart disease (VHD) when there is discrepancy between symptoms and resting markers of severity. The aim of this study is to determine the prognostic value of exercise stress echocardiography in patients with common valve lesions. One hundred and fifteen patients with VHD (aortic stenosis (n=28); aortic regurgitation (n=35); mitral regurgitation, (n=26); mitral stenosis (n=26)), and age- and sex-matched controls (n=39) with normal ejection fraction underwent exercise stress echocardiography. The primary endpoint was a composite of death or hospitalization for heart failure. Asymptomatic VHD patients had lower exercise capacity than controls and 37% of patients achieved 60 mmHg) was associated with an increased risk of death or hospital admission (14% vs 1%, P<0.0001). The assessment of contractile reserve did not offer additional predictive value. In conclusion, an abnormal stress echocardiogram is associated with death and hospitalization with heart failure at 2 years. Stress echocardiography should be considered as part of the routine follow-up of all asymptomatic patients with VHD.

  9. Stress-echocardiography in idiopathic dilated cardiomyopathy: instructions for use

    Directory of Open Access Journals (Sweden)

    Neskovic Aleksandar N

    2005-02-01

    Full Text Available Abstract A number of studies have suggested that stress-echocardiography may be used for prognostic stratification in patients with idiopathic dilated cardiomyopathy. There is no consensus on which protocol or which measurements of left ventricular contractile reserve to use. The most frequently used protocol is low-dose dobutamine stress-echocardiography, and most commonly used measures of left ventricular systolic performance are ejection fraction, wall motion score index and cardiac power output. Stress-echocardiography has been shown to predict improvement in cardiac function in patients with recently diagnosed dilated cardiomyopathy, as well as to predict which patients will benefit from the treatment with beta-blockers. Most importantly, stress-echocardiography can identify patients with worse prognosis in terms of cardiac death and need for transplantation. Additionally, contractile reserve is closely correlated with maximal oxygen consumption and can even be used for further stratification in patients with maximal oxygen consumption between 10 and 14 ml/kg/min. Future studies are needed for head-to-head comparison of various protocols in an attempt to make standardization in the assessment of patients with dilated cardiomyopathy.

  10. Differential Diagnosis of Cardiac Malposition by Fetal Echocardiography

    Institute of Scientific and Technical Information of China (English)

    Ying WU; Feng TAO; Tao LIU; Ling ZANG; Shi-long LIU

    2009-01-01

    Objectives To explore the method and operating skill of fetal echocardiography in diagnosing cardiac malposition. Methods 91 consecutive fetuses were studied (control: 50 cases, cardiac malposition : 41 cases) between 2003 and 2008. The position of fetal heart was evaluated according to the fetal posture and the visceral situs by fetal routine scan-ning. The detailed echocardiography should be performed in the differential diagnosis of cardiac lesions when the heart was found to be abnormal position. Results In the control group, all fetuses were levocardia. 39 cases of cardiac mal-positions were detected by fetal echocardiography, included 25 fetuses with dextrocardia, 6 mesocard, 5 with levover-sion of heart, 3 common heart of conjoined twins and 2 extrathorax heart. Two of dextroversion were missed by fetal routine scanning, but found by autopsy or operation after birth. Conclusions When the abnormal visceral situs was found by fetal routine scanning, there is exceedingly high incidence of cardiac malpositions. Proficiently operating skill of fetal echocardiography is helpful to detect abnormal fetal cardiac position.

  11. Low-dose adenosine stress echocardiography: Detection of myocardial viability

    Directory of Open Access Journals (Sweden)

    Nedeljkovic Milan

    2003-06-01

    Full Text Available Abstract Objective The aim of this study was to evaluate the diagnostic potential of low-dose adenosine stress echocardiography in detection of myocardial viability. Background Vasodilation through low dose dipyridamole infusion may recruit contractile reserve by increasing coronary flow or by increasing levels of endogenous adenosine. Methods Forty-three patients with resting dyssynergy, due to previous myocardial infarction, underwent low-dose adenosine (80, 100, 110 mcg/kg/min in 3 minutes intervals echocardiography test. Gold standard for myocardial viability was improvement in systolic thickening of dyssinergic segments of ≥ 1 grade at follow-up. Coronary angiography was done in 41 pts. Twenty-seven patients were revascularized and 16 were medically treated. Echocardiographic follow up data (12 ± 2 months were available in 24 revascularized patients. Results Wall motion score index improved from rest 1.55 ± 0.30 to 1.33 ± 0.26 at low-dose adenosine (p Conclusion Low-dose adenosine stress echocardiography test has high diagnostic potential for detection of myocardial viability in the group of patients with left ventricle dysfunction due to previous myocardial infarction. Low dose adenosine stress echocardiography may be adequate alternative to low-dose dobutamine test for evaluation of myocardial viability.

  12. Update of the echocardiography core syllabus of the European Association of Cardiovascular Imaging (EACVI).

    Science.gov (United States)

    Cosyns, Bernard; Garbi, Madalina; Separovic, Jadranka; Pasquet, Agnes; Lancellotti, Patrizio

    2013-09-01

    The update of the Echocardiography Core Syllabus of European Association of Cardiovascular Imaging (EACVI) is now available online. The Echocardiography Core Syllabus enumerates the elements of knowledge to be taught, represents a framework for the development of local training curricula and provides expected learning outcomes to the echocardiography learner.

  13. Quantitative assessment of harmonic power doppler myocardial perfusion imaging with intravenous levovist™ in patients with myocardial infarction: comparison with myocardial viability evaluated by coronary flow reserve and coronary flow pattern of infarct-related artery

    Directory of Open Access Journals (Sweden)

    Nagai Kunihiko

    2005-08-01

    Full Text Available Abstract Background Myocardial contrast echocardiography and coronary flow velocity pattern with a rapid diastolic deceleration time after percutaneous coronary intervention has been reported to be useful in assessing microvascular damage in patients with acute myocardial infarction. Aim To evaluate myocardial contrast echocardiography with harmonic power Doppler imaging, coronary flow velocity reserve and coronary artery flow pattern in predicting functional recovery by using transthoracic echocardiography. Methods Thirty patients with anterior acute myocardial infarction underwent myocardial contrast echocardiography at rest and during hyperemia and were quantitatively analyzed by the peak color pixel intensity ratio of the risk area to the control area (PIR. Coronary flow pattern was measured using transthoracic echocardiography in the distal portion of left anterior descending artery within 24 hours after recanalization and we assessed deceleration time of diastolic flow velocity. Coronary flow velocity reserve was calculated two weeks after acute myocardial infarction. Left ventricular end-diastolic volumes and ejection fraction by angiography were computed. Results Pts were divided into 2 groups according to the deceleration time of coronary artery flow pattern (Group A; 20 pts with deceleration time ≧ 600 msec, Group B; 10 pts with deceleration time Conclusion The preserved microvasculature detecting by myocardial contrast echocardiography and coronary flow velocity reserve is related to functional recovery after acute myocardial infarction.

  14. Doppler lidar wind measurement with the edge technique

    Science.gov (United States)

    Korb, C. Laurence; Gentry, Bruce M.

    1992-01-01

    The edge technique is a new and powerful method for measuring small frequency shifts. Range resolved lidar measurements of winds can be made with high accuracy and high vertical resolution using the edge technique to measure the Doppler shift of an atmospheric backscattered signal from a pulsed laser. The edge technique can be used at near-infrared or visible wavelengths using well developed solid state lasers and detectors with various edge filters. In the edge technique, the laser frequency is located on the steep slope of the spectral response function of a high resolution optical filter. Due to the steep slope of the edge, very small frequency shifts cause large changes in measured signal. The frequency of the outgoing laser pulse is determined by measuring its location on the edge of the filter. This is accomplished by sending a small portion of the beam to the edge detection setup where the incoming light is split into two channels - an edge filter and an energy monitor channel. The energy monitor signal is used to normalize the edge filter signal for magnitude. The laser return backscattered from the atmosphere is collected by a telescope and directed through the edge detection setup to determine its frequency (location on the edge) in a similar manner for each range element. The Doppler shift, and thus the wind, is determined from a differential measurement of the frequency of the outgoing laser pulse and the frequency of the laser return backscattered from the atmosphere. We have conducted simulations of the performance of an edge lidar system using an injection seeded pulsed Nd:YAG laser at 1.06 microns. The central fringe of a Fabry-Perot etalon is used as a high resolution edge filter to measure the shift of the aerosol return.

  15. Digital signal processor-based real-time optical Doppler tomography system.

    Science.gov (United States)

    Yan, Shikui; Piao, Daqing; Chen, Yueli; Zhu, Quing

    2004-01-01

    We present a real-time data-processing and display unit based on a custom-designed digital signal processor (DSP) module for imaging tissue structure and Doppler blood flow. The DSP module is incorporated into a conventional optical coherence tomography system. We also demonstrate the flexibility of embedding advanced Doppler processing algorithms in the DSP module. Two advanced velocity estimation algorithms previously introduced by us are incorporated in this DSP module. Experiments on Intralipid flow demonstrate that a pulsatile flow of several hundred pulses per minute can be faithfully captured in M-scan mode by this DSP system. In vivo imaging of a rat's abdominal blood flow is also presented.

  16. Impact of individual and cumulative coronary risk factors on coronary flow reserve assessed by dobutamine stress echocardiography.

    Science.gov (United States)

    Ahmari, Saeed A L; Bunch, T Jared; Modesto, Karen; Stussy, Vicky; Dichak, Amy; Seward, James B; Pellikka, Patricia A; Chandrasekaran, Krishnaswamy

    2008-06-15

    Traditional cardiovascular risk factors have been shown to cause microvascular dysfunction. Most studies that have evaluated microcirculation rely on invasive measurement tools. We used dobutamine stress echocardiography, a validated method to measure coronary flow velocity (CFV) and coronary flow reserve (CFR), in a previously unstudied population without known significant coronary artery disease to determine the impact of traditional risk factors on CFR. Consecutive patients who had no evidence of regional wall motion abnormalities at rest or during dobutamine stress echocardiography were studied. Left anterior descending artery CFV was measured at baseline and at peak dobutamine stress and CFR was calculated as the ratio of peak stress CFV to baseline CFV. Fifty-nine consecutive patients (28 men) with mean age of 66.8+/-14.5 years were studied. CFR was lower in patients with diabetes mellitus (DM) compared with those without (1.7+/-0.74 vs 2.48+/-0.98, p50 mm Hg), and obesity with a wide pulse pressure. In a multivariate model, DM, obesity, and wide pulse pressure were significantly associated with variation in CFR (p<0.0008). In conclusion, CFR was abnormal in patients with DM, hypertension, and obesity. CFR impairment is exaggerated as the number of risk factors increases. Despite a negative dobutamine stress echocardiographic result, aggressive risk factor assessment and control should be implemented in patients with coronary risk factors due to an underlying abnormal CFR.

  17. Computer-based training in two-dimensional echocardiography using an echocardiography simulator.

    Science.gov (United States)

    Weidenbach, Michael; Wild, Florentine; Scheer, Kathrin; Muth, Gerhard; Kreutter, Stefan; Grunst, Gernoth; Berlage, Thomas; Schneider, Peter

    2005-04-01

    Two-dimensional (2D) echocardiography is a user-dependent technique that poses some inherent problems to the beginner. The first problem for beginners is spatial orientation, especially the orientation of the scan plane in reference to the 3-dimensional (3D) geometry of the heart. The second problem for beginners is steering of the ultrasound probe. We have designed a simulator to teach these skills. On a computer screen a side-by-side presentation of a 3D virtual reality scene on the right side and a 2D echocardiographic view on the left side is given. The virtual scene consists of a 3D heart and an ultrasound probe with scan plane. The 2D echocardiographic image is calculated from 3D echocardiographic data sets that are registered with the heart model to achieve spatial and temporal congruency. The displayed 2D echocardiographic image is defined and controlled by the orientation of the virtual scan plane. To teach hand-eye coordination we equipped a dummy transducer with a 3D tracking system and placed it on a dummy torso. We have evaluated the usability of the simulator in an introductory course for final-year medical students. The simulator was graded realistic and easy to use. According to a subjective self-assessment by a standardized questionnaire the aforementioned skills were imparted effectively.

  18. Low-dose adenosine stress echocardiography: Detection of myocardial viability

    Science.gov (United States)

    Djordjevic-Dikic, Ana; Ostojic, Miodrag; Beleslin, Branko; Nedeljkovic, Ivana; Stepanovic, Jelena; Stojkovic, Sinisa; Petrasinovic, Zorica; Nedeljkovic, Milan; Saponjski, Jovica; Giga, Vojislav

    2003-01-01

    Objective The aim of this study was to evaluate the diagnostic potential of low-dose adenosine stress echocardiography in detection of myocardial viability. Background Vasodilation through low dose dipyridamole infusion may recruit contractile reserve by increasing coronary flow or by increasing levels of endogenous adenosine. Methods Forty-three patients with resting dyssynergy, due to previous myocardial infarction, underwent low-dose adenosine (80, 100, 110 mcg/kg/min in 3 minutes intervals) echocardiography test. Gold standard for myocardial viability was improvement in systolic thickening of dyssinergic segments of ≥ 1 grade at follow-up. Coronary angiography was done in 41 pts. Twenty-seven patients were revascularized and 16 were medically treated. Echocardiographic follow up data (12 ± 2 months) were available in 24 revascularized patients. Results Wall motion score index improved from rest 1.55 ± 0.30 to 1.33 ± 0.26 at low-dose adenosine (p < 0.001). Of the 257 segments with baseline dyssynergy, adenosine echocardiography identified 122 segments as positive for viability, and 135 as necrotic since no improvement of systolic thickening was observed. Follow-up wall motion score index was 1.31 ± 0.30 (p < 0.001 vs. rest). The sensitivity of adenosine echo test for identification of viable segments was 87%, while specificity was 95%, and diagnostic accuracy 90%. Positive and negative predictive values were 97% and 80%, respectively. Conclusion Low-dose adenosine stress echocardiography test has high diagnostic potential for detection of myocardial viability in the group of patients with left ventricle dysfunction due to previous myocardial infarction. Low dose adenosine stress echocardiography may be adequate alternative to low-dose dobutamine test for evaluation of myocardial viability. PMID:12812523

  19. DOPPLER ANALYSIS IN PREGNANCY INDUCED HYPERTENSION

    Directory of Open Access Journals (Sweden)

    Tushar

    2014-12-01

    Full Text Available A study of 50 cases was conducted to evaluate the role of Colour Doppler imaging in pregnancy induced hypertension with women over 28 weeks of gestation, the initial scan was performed immediately after the diagnosis of PIH to avoid any influence of treatment on Doppler evaluation. This study was aimed to analyze the blood flow in umbilical artery, maternal uterine artery & fetal middle cerebral artery using Doppler ultrasound.

  20. In vitro evaluation of a micro-Doppler catheter for detection and aspiration of venous air emboli.

    Science.gov (United States)

    Bigeleisen, Paul E

    2007-11-01

    Venous air embolism (VAE) is a potentially fatal complication of surgery when open veins at a surgical site are exposed to ambient air pressure which exceeds the pressure in the venous system. Common techniques of detecting VAE are precordial Doppler monitoring and transesophogeal echocardiography. Precordial Doppler monitoring has poor accuracy and transesophogeal echocardiography is expensive and user-intensive. In both methods, a separate catheter must be inserted into the vena cava so that an embolus may be aspirated if it is detected. We created a micro-Doppler assembly using two ceramic transducers fitted over a 5.8F multiorifice central venous catheter. This micro-Doppler catheter (MDC) was tested in vitro using a static tank and an artificial vena cava (AVC). The MDC was also tested for acoustic pressure and current leakage in the static tank and for heat generation and cavitation in the AVC. The MDC was able to detect bubbles more than 2 mm in diameter with 100% accuracy. A blinded observer was able to identify the onset of vapor lock in 10 of 10 trials. The same observer was able to terminate vapor lock in 10 of 10 trials. The acoustic pressures measured were <1.8 MPa. There was no increase in temperature in the AVC over 24 h and there was no evidence of cavitation in the AVC over 4 h. We have created a MDC that can detect air emboli and relieve vapor lock in a simulated vena cava and atrium. This catheter could be placed percutaneously in the vena cava. Based on the measurements of acoustic pressure, temperature in the AVC and lack of cavitation in the AVC, the device appears to be safe for use in humans. More studies are required to determine if the catheter could be used to detect and aspirate VAE during surgeries where VAE is likely, such as sitting craniotomy.