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Vom Base Camp zum Produkt - die Digitalstrategie von Linde. CHEM-ING-TECH 2018. [DOI: 10.1002/cite.201855003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Diastolic filling pattern and left ventricular diameter predict response and prognosis after cardiac resynchronisation therapy. Heart 2007; 94:1026-31. [PMID: 17984216 DOI: 10.1136/hrt.2007.126193] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE To investigate predisposing factors for cardiac resynchronisation therapy (CRT) response. DESIGN Single-centre study. SETTING University hospital in Germany. PATIENTS 122 consecutive patients with heart failure (mean (SD) age 65 (11) years; ischaemic/non-ischaemic 41%/55%; New York Heart Association (NYHA) class 3.1 (0.3); left ventricular ejection fraction 24.4 (8.1)%; QRS width 170 (32) ms, quality of life (QoL) 43.5 (19.2)) with an indication for CRT and demonstrated left ventricular dyssynchrony by echocardiography including tissue Doppler imaging. INTERVENTIONS Besides laboratory testing of clinical variables, results of ECG, echocardiography including tissue Doppler imaging, invasive haemodynamics, measures of QoL and of exercise capacity were obtained before CRT implantation and during follow-up. MAIN OUTCOME MEASURE Responders were predefined as patients with improvement by one or more NYHA functional class or reduction of left ventricular end-systolic volume by 10% or more during follow-up. Mean (SD) follow-up was 418 (350) days. RESULTS Overall, 70.5% of patients responded to CRT. Responders had a significantly improved survival compared with non-responders (96.2% vs 45.5%, log-rank p<0.001). On univariate analysis, left ventricular end-diastolic diameter, left ventricular end-systolic diameter (LVESD), E/A ratio, a restrictive filling pattern, mean pulmonary artery pressure, pulmonary capillary pressure, N-terminal pro-brain natriuretic peptide and Vo(2)max were significant predictors of outcome. On multivariate analyses, LVESD (p = 0.009; F = 7.83), pulmonary capillary pressure (p = 0.015, F = 6.61) and a restrictive filling pattern (p = 0.026, F = 5.707) remained significant predictors of response. CONCLUSIONS Despite treatment according to present guidelines nearly 30% of patients had no benefit from CRT treatment in a clinical setting. On multivariate analyses, patients with an increased left ventricular end-systolic diameter and concomitant diastolic dysfunction had a significantly worse outcome.
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Aminoterminal B-type pro-natriuretic peptide as a marker of recovery after high-risk coronary artery bypass grafting in patients with ischemic heart disease and severe impaired left ventricular function. J Heart Lung Transplant 2006; 25:596-602. [PMID: 16678040 DOI: 10.1016/j.healun.2005.12.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2005] [Revised: 06/01/2005] [Accepted: 12/27/2005] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Aminoterminal B-type pro-natriuretic peptide (NT-proBNP) is a reliable indicator of heart failure severity. Levels of NT-proBNP are markedly increased in patients with coronary artery disease (CAD) and severely impaired left ventricular (LV) function. The aim of our study was to assess the impact of NT-proBNP levels after high-risk coronary artery bypass grafting (CABG) with regard to recovery potential. METHODS Between 1998 and 2004, 121 patients with CAD and severely impaired LV function, who were undergoing CABG, were investigated. Their mean age was 64 +/- 11 years. All patients were in New York Heart Association (NYHA) Class III/IV status; LV ejection fraction (EF) was 20 +/- 6%. All survivors underwent follow-up (59 +/- 34 months) spiroergometric, electrocardiographic (ECG) and echocardiographic assessment and were tested for routine blood controls and NT-proBNP levels (Roche, Mannheim, Germany). RESULTS The survival rate after 8 years was 70%. All survivors received follow-up assessment. Among survivors the median NT-proBNP level at follow-up was 896 (521 to 1,687) pg/ml. The maximum oxygen uptake was 14.6 +/- 4.9 ml/min/kg, and EF increased to 42% at follow-up among all survivors. On dichotomizing survivors into two groups with NT-proBNP levels above and below the median, the post-operative body mass index was significantly higher in the high NT-proBNP group (p = 0.036). EF (p = 0.028) and NYHA classification (p < 0.05) improved significantly in both groups, with a tendency toward higher EF in the low NT-proBNP group. CONCLUSIONS Patients undergoing a high-risk CABG procedure have a survival rate comparable to heart transplantation patients and show a potential for clinical and myocardial recovery. NT-proBNP use a useful marker for recovery after a high-risk CABG procedure, with significant correlation with clinical parameters.
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Can early diastolic velocity of the mitral annulus predict survival in patients with impaired left-ventricular function? NATURE CLINICAL PRACTICE. CARDIOVASCULAR MEDICINE 2005; 2:388-9. [PMID: 16119697 DOI: 10.1038/ncpcardio0273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
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Abstract
Primary cardiac tumours are quite rare and most of these tumours are benign. In this report, a patient presented with heart failure symptoms attributable to severe mitral valve stenosis. Echocardiography showed a dense left atrial mass causing functional mitral valve obstruction. The morphological and intraoperative presentation was highly suggestive of a myxoma but histopathological examination found a primary pedunculated cardiac angiosarcoma. The role of two dimensional and transoesophageal echocardiography in the assessment of cardiac masses and tumours is discussed.
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Stroke volume and mitral annular velocities. ACTA ACUST UNITED AC 2004; 93:799-806. [PMID: 15492895 DOI: 10.1007/s00392-004-0132-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2004] [Accepted: 06/22/2004] [Indexed: 01/07/2023]
Abstract
The aim of this study was to assess the impact of stroke volume (SV) on mitral annular velocities derived from tissue Doppler imaging (TDI). To this end, conventional echocardiographic variables and TDI derived mitral annular velocities (S', E', A') were obtained in 14 patients (pts) with increased SV (due to primary mitral (n=12) (ISV group)), in 41 pts with reduced SV (due to ischemic (n=27) or dilated cardiomyopathy (n=9) or hypertensive heart disease (n=5) (RSV group)) and 29 asymptomatic controls with normal SV (CON group). Systolic (S') and early diastolic (E') mitral annular velocities were elevated in the ISV group in the comparison to the CON group, but were significantly reduced in the RSV group. Late diastolic annular velocities (A') did not differ between the ISV and the CON group, but were lowest in the RSV group. On simple linear regression analysis, SV was significantly related to S' (r=0.74, p<0.001), to E' (r=0.74, p<0.001) and to A' (r=0.43, p<0.01). On multiple regression analysis, SV was a stronger independent predictor of S' and E' than conventional systolic or diastolic echocardiographic variables. Thus, stroke volume has a significant impact on TDI derived systolic (S') and early diastolic (E') mitral annular velocities. This should be considered, when TDI is used in the evaluation of LV performance or in the estimation of filling pressures.
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MESH Headings
- Adult
- Aged
- Aortic Valve Insufficiency/diagnostic imaging
- Aortic Valve Insufficiency/physiopathology
- Blood Flow Velocity/physiology
- Cardiomyopathy, Dilated/diagnostic imaging
- Cardiomyopathy, Dilated/physiopathology
- Cardiomyopathy, Hypertrophic/diagnostic imaging
- Cardiomyopathy, Hypertrophic/physiopathology
- Coronary Disease/diagnostic imaging
- Coronary Disease/physiopathology
- Echocardiography, Doppler, Color
- Echocardiography, Doppler, Pulsed
- Female
- Heart Diseases/diagnostic imaging
- Heart Diseases/physiopathology
- Humans
- Hypertension/complications
- Hypertension/diagnostic imaging
- Hypertension/physiopathology
- Male
- Middle Aged
- Mitral Valve/diagnostic imaging
- Mitral Valve Insufficiency/diagnostic imaging
- Mitral Valve Insufficiency/physiopathology
- Myocardial Contraction/physiology
- Observer Variation
- Stroke Volume/physiology
- Ventricular Dysfunction, Left/diagnostic imaging
- Ventricular Dysfunction, Left/physiopathology
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[Aneurysm of the subclavian artery after operatively corrected coarctation of the aorta: 20 years of follow-up and review of the current literature]. ZEITSCHRIFT FUR KARDIOLOGIE 2003; 92:339-46. [PMID: 12707794 DOI: 10.1007/s00392-003-0914-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
We report of long-term follow-up of a combined fusiform aneurysm of the right subclavian artery extending to the thyreocervical trunk (3.2 x 2.8 x 2.2 cm (width x height x depth)) in a 33-year old patient. As a newborn, the clinical diagnosis of an aortic isthmus stenosis was made without need for intervention at this stage. Further development of the child remained unremarkable until the age of eleven years when he experienced dizziness after sporting activities. Due to clinically proven progress, cardiac catheterization was performed and confirmed the initial diagnosis of a juxtaductale stenosis of the aortic isthmus, which was operated thereafter with an end-to-end anastomosis. Furthermore, an aneurysm of the right subclavian artery was revealed. Since then, non-invasive routine follow-up showed no significant worsening of this aneurysm, which extends to the thyreocervical trunk. The patient has been event free and completely asymptomatic. This case report illustrates the more than twenty years of follow-up of an asymptomatic combined fusiform aneurysm of the subclavian artery and thyreocervical trunk and provides a review of the literature on this topic.
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Abstract
Cardiomyopathy is often seen in patients with a long history of acromegaly. In order to screen for perfusion abnormalities, patients with active acromegaly without evidence for coronary heart disease were examined by single photon emission computed tomography (SPECT). The study included a group of 11 strictly selected patients with active acromegaly (7 males and 4 females; age 51 +/- 12 y [mean +/- S.D.]) with elevated age-adjusted IGF-I levels (IGF-I 569 +/- 193 micro g/l; GH 31.2 +/- 56.3 micro g/l) compared to an age- and sex-matched non-acromegalic control group with comparable muscle mass index of the left ventricle (126 +/- 41 active vs. 122 +/- 33 g/m 2 control group) and body mass index (26.6 +/- 2.7 vs. 27.0 +/- 5.0 kg/m 2). To address this issue, myocardial perfusion was investigated by single photon emission computed tomography (SPECT) using a triple head gamma-camera. 70 MBq 201TlCl was injected, and post-stress (from bicycle ergometer) images were obtained. Images were interpreted quantitatively by bull's eye polary map (16 regions of the left ventricle) and were compared to the control group. In the patients with active acromegaly, the mean nuclide uptake of the 16 regions of the left ventricle after bicycle stress examination was lower than in the control group (82.99 +/- 2.85 active vs 85.48 +/- 1.29 control group, p < 0.01). Non-homogeneity of nuclide uptake was defined as the standard deviations of the 16 regions and was higher in patients with active acromegaly (11.11 +/- 2.35 active vs. 8.77 +/- 1.39 control group, p < 0.01). In conclusion, myocardial perfusion is impaired in patients with active acromegaly, thus representing an early stage of cardiac involvement in acromegaly that may be directly mediated by growth hormone excess.
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[Not Available]. ZEITSCHRIFT FUR KARDIOLOGIE 2002; 91:667. [PMID: 24733482 DOI: 10.1007/s003920200067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
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Tei-Index in coronary artery disease--validation in patients with overall cardiac and isolated diastolic dysfunction. ZEITSCHRIFT FUR KARDIOLOGIE 2002; 91:472-80. [PMID: 12219695 DOI: 10.1007/s00392-002-0808-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND The index "isovolumic contraction time and isovolumic relaxation time divided by ejection time" ("Tei-Index") has been demonstrated to provide useful information about disease severity and prognosis in patients with dilated cardiomyopathy and cardiac amyloidosis. In patients with coronary artery disease (CAD), the diagnostic utility of this index is unclear. We attempted to validate the Tei-Index in CAD patients with overall cardiac or isolated diastolic dysfunction. METHODS AND RESULTS Sixty subjects were included who underwent left heart catheterization for invasive measurement of left ventricular end-diastolic pressure (LVEDP): 20 symptomatic CAD patients with overall cardiac dysfunction (defined by a LV ejection fraction (EF) < 45% (mean 27 +/- 8%) and a LVEDP > or = 16 mmHg, (mean 22 +/- 6 mmHg), NYHA class 2.7 +/- 0.4, OCD group), 29 symptomatic CAD patients with isolated diastolic dysfunction (defined by an EF > 45% (mean 55 +/- 8%), a normal end-diastolic diameter index (mean 2.8 +/- 0.4 cm/m2) and a LVEDP > or = 16 mmHg (mean 22 +/- 6 mmHg), NYHA class 2.3 +/- 0.4, IDD group) and 11 asymptomatic control subjects (EF 65 +/- 9%, LVEDP 11 +/- 4 mmHg, CON group). After conventional 2-D- and Doppler echocardiographic examination, the Tei-Index was obtained. The Tei-Index was easily and reproducibly measured in all study subjects. In the OCD group, isovolumic contraction time was prolonged and ejection time was shortened in comparison to the CON group, resulting in a significantly increased Tei-Index (0.71 +/- 0.28 vs 0.40 +/- 0.11, p < 0.01). In the IDD group, isovolumic relaxation time was prolonged and isovolumic contraction time was shortened in comparison to controls, resulting in a largely unchanged Tei-Index (0.45 +/- 0.14, p = ns). Receiver operating characteristic curve analysis for the Tei-Index yielded an area under the curve of 0.92 +/- 0.04 for separating patients with vs without OCD. Using a Tei-Index > 0.49 as a cut-off, OCD patients were identified with a sensitivity of 96% and a specificity of 86%. CONCLUSION The Tei-Index is a valid and readily derived indicator of global cardiac dysfunction in CAD patients with impaired systolic and diastolic LV performance. The use of this index seems to be limited in CAD patients with primary diastolic dysfunction.
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Acromegaly: evidence for a direct relation between disease activity and cardiac dysfunction in patients without ventricular hypertrophy. Clin Endocrinol (Oxf) 2002; 56:595-602. [PMID: 12030909 DOI: 10.1046/j.1365-2265.2002.01528.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
BACKGROUND AND AIMS Cardiac abnormalities, such as cardiomegaly and congestive heart failure, occur frequently in advanced acromegaly. Abnormalities of systolic and diastolic function, mostly associated with left ventricular (LV) hypertrophy, have been reported. The impact of disease activity on LV performance in patients with normal or slightly elevated LV muscle mass has not been demonstrated. PATIENTS AND METHODS Conventional two-dimensional/Doppler echocardiography and tissue Doppler imaging (TDI) of the mitral annulus were performed in 13 patients with active acromegaly (AA) and normal or slightly elevated LV muscle mass (< 140 g/m2) and in 19 cured/well-controlled patients (CA). A group of 21 volunteers without symptoms or signs of cardiac disease served as controls (CON). The combined myocardial performance index (Tei-Index) was determined in all patients and controls. RESULTS Muscle mass index of the left ventricle, ejection fraction, fractional shorting, E/ET-ratio, systolic (ST) and late diastolic (AT) annular velocities did not differ significantly between the three groups. In the AA group, the early diastolic annular velocity ET[7.13 +/- 2.11 (AA); 9.83 +/- 3.29 (CA); 10.10 +/- 1.70 m/s (CON); P < 0.05 AA vs. CA, P < 0.005 AA vs. CON] and the ET/AT-ratio [0.71 +/- 0.26 (AA); 0.95 +/- 0.33 (CA); 1.00 +/- 0.15 m/s (CON); P < 0.05 AA vs. CA, P < 0.005 AA vs. CON] were significantly reduced. Patients with AA had a longer deceleration time [209 +/- 19 (AA); 179 +/- 22 (CA); 185 +/- 26 ms (CON); P < 0.05]. The Tei-Index was significantly higher in AA in comparison with CON [0.50 +/- 0.15 (AA); 0.48 +/- 0.12 (CA); 0.41 +/- 0.10 (CON); P < 0.05 AA vs. CON]. Subjects with CA did not differ significantly from controls with respect to 2-D/Doppler echo- and TDI-derived parameters. CONCLUSION The data demonstrate that diastolic dysfunction can be verified by tissue Doppler imaging in patients with active acromegaly with normal or slightly elevated muscle mass of the left ventricle and seems to be related to disease activity. The Tei-Index as a sensitive combined myocardial performance index can be used to complete the assessment of systolic and diastolic LV performance in acromegalic patients.
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[Sinus node dysfunction with intermittent sinus arrest and AV-nodal escape rhythm as initial manifestation of pheochromocytoma]. ZEITSCHRIFT FUR KARDIOLOGIE 2002; 91:81-7. [PMID: 11963212 DOI: 10.1007/s392-002-8376-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A 25-year-old male student complained about episodic palpitations, dizziness, nausea and headache 5 years prior to presentation. No otorhinolaryngic, neurologic or gastrointestinal causes were identified. Several ECG recordings revealed sinus node dysfunction with intermittent sinus arrest and AV-nodal escape rhythm. The patient was given a permanent DDD-pacemaker. Six months later, the clinical symptoms were unchanged. During an attack, physical examination revealed paleness, diffuse sweating and an arterial blood pressure of 250/130 mmHg, which decreased to 120/80 mmHg within a few minutes. Abdominal ultrasound and abdominal computed tomographic scan demonstrated the presence of a large (6.4 x 5.5 cm) left-sided adrenal mass. Two 24-h-urinary collections demonstrated elevated noradrenaline (mean 315 micrograms/24 h, normal < 80 micrograms/24 h) and adrenaline (mean 268 micrograms/24 h, normal < 20 mg/24 h) levels. Blood samples, which were drawn during excessive blood pressure rise, revealed elevation of plasma catecholamines (6.793 pg/ml for adrenaline (normal 50-150 pg/ml) and 10.424 pg/ml for noradrenaline (normal 200-500 pg/ml), so that the diagnosis of pheochromocytoma was considered established. The tumor was successfully removed during laparascopic surgery. After surgery, the patient remained well and normotensive. Three months later, several long-term ECG recordings showed sinus arrhythmia with no evidence of sinus arrest or AV-nodal escape rhythm, so that the DDD pacemaker was turned off. This case underlines that sinus node dysfunction with intermittent sinus arrest and AV-nodal escape rhythm is a potential early manifestation of a pheochromocytoma. These changes seem to disappear after successful removal of the tumor.
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Abstract
OBJECTIVE Patients with acromegaly have an increased risk of ventricular dysrhythmias and sudden death. Late potentials in a signal-averaged electrocardiogram (SAECG), a predictor of ventricular dysrhythmias, are frequently seen in patients after previous myocardial infarction, but little is known about the prevalence of late potentials in acromegaly. The aim of our study was to investigate the prevalence of late potentials in patients with acromegaly and their relation to the activity of the disease and to myocardial hypertrophy. PATIENTS The study included 48 patients with acromegaly [27 males, 21 females, mean age 52.3 +/- 14.2 years, 16 active disease, 32 cured or 'well controlled', under treatment with sandostatin analogues (12/32)] and 38 healthy volunteers as a control group. RESULTS Late potentials were detected in 9/16 (56%) patients with active acromegaly vs. 2/32 (6%) with cured/well controlled acromegaly (P = 0.001), defined as normal age-related IGF-1 levels and GH levels suppressible below 1 microg/l after an oral glucose load (75 g). Late potentials were not related to muscle mass index (127 +/- 35 active vs. 123 +/- 34 g/m2 cured/well controlled). The association of disease activity with the detection of late potentials was independent of age, gender, duration of the disease and body mass index. In comparison to the control group, the prevalence of late potentials was significantly higher in patients with acromegaly (23%) than in the control group (0%; P < 0.001). CONCLUSIONS Late potentials in the SAECG are frequently seen in active acromegaly and may represent an early and sensitive parameter to detect myocardial injury in acromegaly.
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Changes in QRS voltage in cardiac tamponade and pericardial effusion: reversibility after pericardiocentesis and after anti-inflammatory drug treatment. J Am Coll Cardiol 2001; 38:219-26. [PMID: 11451278 DOI: 10.1016/s0735-1097(01)01313-4] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
OBJECTIVES The goal of this study was to define the association between low QRS voltage and cardiac tamponade or pericardial effusion and to assess the reversibility of low QRS voltage after therapeutic procedures. BACKGROUND It is unclear whether low QRS voltage is a sign of cardiac tamponade or whether it is a sign of pericardial effusion per se. METHODS In a prospective study design, we recorded consecutive 12-lead electrocardiograms and echocardiograms in 43 patients who were referred to our institution for evaluation and therapy of a significant pericardial effusion. Cardiac tamponade was present in 23 patients (53%). Low QRS voltage (defined as maximum QRS amplitude <0.5 mV in the limb leads) was found in 14 of these 23 subjects (61%). Nine of these 14 patients were treated by pericardiocentesis (group A). Five patients received anti-inflammatory medication (group B). Group C consisted of nine patients with pericarditis and significant pericardial effusion who had no clinical evidence of tamponade. RESULTS In group A, low QRS voltage remained largely unchanged immediately after successful pericardiocentesis (0.36 +/- 0.17 mV before vs. 0.42 +/- 0.21 mV after, p = NS), but QRS amplitude recovered within a week (0.78 +/- 0.33 mV, p < 0.001). In group B, the maximum QRS amplitude increased from 0.40 +/- 0.20 mV to 0.80 +/- 0.36 mV (p < 0.001) within six days. In group C, all patients had a normal QRS amplitude initially (1.09 +/- 0.55 mV) and during a seven-day follow-up (1.10 +/- 0.56 mV, p = NS). CONCLUSIONS Low QRS voltage is a feature of cardiac tamponade but not of pericardial effusion per se. Our findings indicate that the presence and severity of cardiac tamponade, in addition to inflammatory mechanisms, may contribute to the development of low QRS voltage in patients with large pericardial effusions.
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A flexible and stable numerical method for simulating the thermal decomposition of wood particles. CHEMOSPHERE 2001; 42:481-490. [PMID: 11219672 DOI: 10.1016/s0045-6535(00)00220-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The objective of this paper is to present a flexible and stable simulation method to predict the thermal conversion of wood particles. A combination of several subprocesses such as heating-up, drying, pyrolysis, gasification and combustion of fuel particles of different properties and sizes represents the global process of thermal conversion. This approach allows for simultaneous processes e.g. reactions in time and covers the entire range between transport-limited (shrinking core) and kinetically limited (reacting core) reaction regimes. Thus, the model is applicable to simulate sufficiently accurate the thermal decomposition of each particle in a packed bed, of which the entire conversion is regarded as the sum of all particle processes. Effects such as fragmentation, swelling, homogeneous reactions e.g. ignition outside a particle are excluded as a tradeoff between complexity and calculation time. However, a description of the particle processes by one-dimensional and transient differential conservation equations for mass and energy is feasible to represent the above mentioned subprocesses. The particles are coupled to the gas phase by heat and mass transfer taking into account the Stefan correction due to the gas outflow during conversion. A general formulation of the conservation equations allows the geometry of a fuel particle to be treated as a plate, cylinder or sphere. In order to achieve a high degree of flexibility, the method distinguishes between data, such as kinetics or material properties and the conversion process, for which relevant data are stored in a data base for easy access and extension. The resulting modules of this subdivision are encapsulated into separate software units cast in a hierarchy of well-defined classes in Tools of Object-oriented Software for Continuum-Mechanics Applications (TOSCA) by object-oriented techniques.
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Abstract
BACKGROUND Congestive heart failure is related to contraction and relaxation abnormalities of the ventricle. Isolated analysis of either mechanism may not be reflective of overall cardiac dysfunction. A combined myocardial performance index (isovolumic contraction time plus isovolumic relaxation time divided by ejection time, 'Tei-Index') has been described which may be more effective for analysis of global cardiac dysfunction than systolic and diastolic measures alone. It was the aim of the present investigation to evaluate the Tei-Index against invasive examination. METHODS AND RESULTS Eighty-one subjects were included in a consecutive manner, among 125 patients undergoing left heart catheterization for invasive measurement of left ventricular end-diastolic pressure; 43 patients had congestive heart failure (35 male, 8 female, 68+/-6 years) defined by NYHA functional class >/=2 (mean 2.5+/-0.5) and left ventricular end-diastolic pressure >/=16 mmHg (mean 20+/-4) and 38 subjects (32 male, 6 female, 66+/-5 years) without symptoms of heart failure (NYHA functional class I) and with normal left ventricular end-diastolic pressure (mean 12+/-3 mmHg) served as a control group. Using conventional echo-Doppler methods, parameters assessed were: ejection fraction, peak velocities of early (E) and late (A) diastolic filling, the E/A ratio, deceleration time, isovolumic contraction time, isovolumic relaxation time and ejection time. The Tei-Index was obtained by subtracting ejection time from the interval between cessation and onset of the mitral flow. The control group and patients with congestive heart failure did not differ with respect to the E/A ratio (0.86+/-0.27 vs 0.90+/-0.44, P=ns), deceleration time (203+/-42 ms vs 206+/-36 ms, P=ns) and isovolumic relaxation time (97+/-16 ms vs 94+/-26 ms, P=ns). The ejection fraction was slightly reduced in patients with congestive heart failure (46+/-11% vs 55+/-8%, P<0.05). The Tei-Index was easily and reproducibly measured in all subjects. The mean value of the Tei-Index was significantly different between the control group and patients with congestive heart failure (0.39+/-0.10 vs 0.60+/-0.18, P<0.001). Receiver operating characteristic curve analysis for the Tei-Index yielded an area under the curve of 0.88+/-0.038. Using a Tei-Index >/=0.47 as the cutpoint, congestive heart failure was identified with a sensitivity of 86% and a specificity of 82%. No correlation was observed between the Tei-Index and heart rate (r=0.22, P=ns), systolic blood pressure (r=0.16, P=ns) or diastolic blood pressure (r=0.08, P=ns). The Tei-Index was significantly related to left ventricular end-diastolic pressure (r=0.46, P<0.01). CONCLUSION The Tei-Index is a sensitive indicator of overall cardiac dysfunction in patients with mild-to-moderate congestive heart failure. The Tei-Index is easily obtained and may be used in the work-up of patients with suspected cardiac dysfunction.
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[Transluminal exclusion of a subclavian artery aneurysm with stent-graft implantation]. ZEITSCHRIFT FUR KARDIOLOGIE 2000; 89:761-5. [PMID: 11077685 DOI: 10.1007/s003920070179] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In a 73 year-old male patient with generalized atherosclerosis, known infrarenal abdominal aortic aneurysm, renal artery stenosis, and coronary artery disease, an aneurysm of the proximal left subclavian artery was successfully excluded by implantation of a JOSTENT-Peripheral stent graft. Angiographic follow up after 6 and 12 months showed an excellent outcome with complete exclusion of the aneurysm. Intravascular ultrasound showed no neo-intimal hyperplasia within the stent. A computed tomography revealed complete thrombosis of the aneurysm.
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Tissue Doppler imaging: a new technique for assessment of pseudonormalization of the mitral inflow pattern. Echocardiography 2000; 17:539-46. [PMID: 11000588 DOI: 10.1046/j.1540-8175.2000.00539.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Left ventricular diastolic dysfunction (LVDD) is a frequent cause of heart failure. Doppler echocardiography has become the method of choice for the noninvasive evaluation of LVDD. However, pseudonormalization (PN) of the mitral inflow often presents a diagnostic challenge in clinical practice. In this setting, we sought to define the role of tissue Doppler imaging (TDI) of the septal mitral annulus. Echocardiography was performed in 36 consecutive subjects (age 59 +/- 10 years). Eighteen of these had diagnosed coronary artery disease (CAD) with recent onset of symptoms (within 3 months), 18 had clinical suspicion of CAD, and 15 had symptoms of heart failure (New York Heart Association [NYHA] Class 2.4 +/- 0.5). The mitral inflow profile (E, A, E/A) was measured by pulsed Doppler, and the deceleration time (DT) and the isovolumic relaxation time (IVRT) were calculated. Peak diastolic velocities of the septal mitral annulus (E(T), A(T), E(T)/A(T)) and the time interval from Q in the ECG to the onset of E(T) were derived from pulsed TDI. Left heart catheterization was performed for direct measurement of left ventricular end-diastolic pressure (LVEDP). PN defined by an E/A ratio > 1 and an LVEDP > or = 16 mmHg was found in nine patients. All patients with PN had symptoms of heart failure (NYHA Class 2.8 +/- 0.5). Patients with and without PN did not differ with respect to the E/A ratio (1.29 +/- 0.44 vs 1.16 +/- 0.23, P = ns), DT (182 +/- 38 msec vs 205 +/- 42 msec, P = ns), and IVRT (88 +/- 24 msec vs 92 +/- 18 msec, P = ns). In the group with PN, a significant reduction of E(T) (5.6 +/- 1.8 cm/sec vs 8.8 +/- 2. 9 cm/sec, P < 0.05) and E(T)/A(T) (0.5 +/- 0.16 vs 0.82 +/- 0.37, P < 0.05) was detected. In the PN group, the Q-E(T) interval was prolonged (404 +/- 48 msec vs 346 +/- 50 msec, P < 0.05). Receiver operating characteristic curve analysis for E(T) yielded an area under the curve of 0.78 +/- 0.06 (P = 0.034) for separating patients with versus without PN. When the combination of E(T) < 7 cm/sec and E(T)/A(T) < 1 was used as cutpoint, PN could be identified with a sensitivity of 83% and a specificity of 79%. There was no significant relation between LVEDP and either E(T) (r = 0.32, P > 0. 2) or the Q-E(T) interval (r = 0.14, P > 0.5). In conclusion, E(T) and the Q-E(T) interval appear to be useful parameters for assessing LV diastolic dysfunction in symptomatic patients with a pseudonormal mitral inflow pattern and elevated filling pressures.
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Usefulness of motion patterns indentified by tissue Doppler echocardiography for diagnosing various cardiac masses, particularly valvular vegetations. Am J Cardiol 1999; 84:1428-33. [PMID: 10606117 DOI: 10.1016/s0002-9149(99)00590-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This study sought to test whether anomalous cardiac and aortic structures can be differentiated from native tissue and artifacts by physical properties of tissue motion using transesophageal tissue Doppler echocardiography (TDE). TDE was employed in 85 consecutive patients after anomalous structures had been detected by conventional transesophageal echocardiography (TEE). The control group consisted of 40 randomized patients. Certainty of diagnosis was divided into 4 categories, and TDE signals were related to particular anomalous structures by a blinded second observer. A mechanical model of a beating ventricle was constructed and suspended in a water bath. Synthetic material was utilized to simulate anomalous intracavitary structures with varying shape, consistency, and attachment. Incoherent motion was present in endocarditic vegetations, freely oscillating thrombi, fourth-degree aortic plaques, Chiari network, valvular prolapse, tumors, and in normal valve leaflets and papillary muscles. Within 15 seconds vegetations could be detected in 17 patients (68%) using TDE versus 5 patients (20%) using only conventional imaging. Coherent motion with a phase difference occurred due to damped oscillation. This phenomenon occurred in 5 patients with thrombi of the left atrial appendage (100%), in 3 ventricular clots (75%), and in 2 hypernephroma in the right atrium (100%). Rapid identification of clots could be achieved in 15 patients (71%) versus 12 patients (57%). Concordant motion was shown in third-degree aortic plaques, postrheumatic valvular lesions, and aortic intramural hematomas, but diagnostic benefit could not be demonstrated. In 41 patients (48%) histopathologic and intraoperative results confirmed echocardiographic findings. Motion patterns could be reproduced independently of the heart rate by model experiments. This study demonstrates that TDE expedites the detection of vegetations in infective endocarditis. Diagnostic certainty can be increased as well for thrombus formations.
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[Hemostatic closure of arterial puncture site using Angio-Seal after diagnostic heart catheterization or coronary intervention]. Herz 1999; 24:607-13. [PMID: 10652673 DOI: 10.1007/bf03044484] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Conventional manual compression and subsequent application of pressure bandages is associated with prolonged immobility and significant patient discomfort. Routine anticoagulation as well as the use of new interventional devices and platelet inhibiting strategies lead to a higher incidence of local bleeding complications after diagnostic cardiac catheterization or coronary angioplasty. Immediate sheath removal increases patient comfort. The Angio-Seal system uses a biodegradable anchor and collagen plug for sealing of arterial puncture sites. Several studies showed the safety and efficacy of this device. Technical deployment success ranges between 88 and 100%. Significant reduction in time to hemostasis allows for earlier patient ambulation and shorter in-hospital stay compared to manual compression with peripheral complications not being increased.
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Tissue Doppler imaging (TDI) for on-line detection of regional early diastolic ventricular asynchrony in patients with coronary artery disease. INTERNATIONAL JOURNAL OF CARDIAC IMAGING 1999; 15:379-90. [PMID: 10595404 DOI: 10.1023/a:1006255329288] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Diastolic filling of the left ventricle is often impaired in patients with coronary artery disease (CAD) in the absence of systolic wall motion abnormalities or previous myocardial infarction. The current study was designed to assess the ability of tissue Doppler imaging (TDI) for on-line detection of regional diastolic wall motion abnormalities to identify CAD in patients with preserved systolic function. 20 normal subjects (age 51 +/- 13 years) and 17 CAD patients with normal systolic function and > or = 70% luminal narrowing of the LAD (age 56 +/- 11 years) were included. Coronary anatomy was unknown to the echocardiographer. In the parasternal short axis and the apical 4-chamber-view, peak tissue velocities of the anterior/inferior and the midseptal/midlateral LV segments during rapid ejection (RE), isovolumic relaxation (IR), rapid filling (RF) and atrial contraction (AC) were analyzed by color-M-Mode-TDI. In the apical view, in 13 of 35 (37%) patients with adequate recordings, myocardial asynchrony was detected during IR: while the septum was moving inwards (red color-coding), the lateral wall was moving outwards (blue/green coding). In the remaining 22 patients (63%) a slow, synchronous outward motion of septum and lateral wall with homogeneous color-coding (blue/green) was seen. Unblinding of the coronary status revealed a critical LAD stenosis in all 13 patients (100%) with myocardial asynchrony. Analysis of midseptal peak velocities during IR revealed positive velocities (1.22 +/- 1.64 cm/s) in CAD patients and negative velocities (-1.39 +/- 0.81 cm/s) in normal subjects. Thus, TDI allowed for the on-line detection of early diastolic asynchrony in 13 of 16 (82%) patients with critical LAD-narrowing. Due to the rapid assessment of regional wall motion abnormalities, TDI might help to identify CAD in patients with normal systolic function.
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Abstract
Left ventricular (LV) diastolic dysfunction is a frequent cause of heart failure. Doppler echocardiography has become the method of choice for the noninvasive evaluation of LV diastolic dysfunction. However, pseudonormalization of mitral inflow often presents a diagnostic problem in clinical practice. We sought to define the role of mitral annulus motion in this setting. We performed echocardiography in 36 consecutive subjects (age 59 +/- 10 years). Eighteen had recently (within 3 months) been diagnosed with coronary artery disease, 18 had clinical suspicion of coronary artery disease, and 15 had symptoms of heart failure (New York Heart Association class 2.4 +/- 0.5). The amplitude (E(M)) and the slope (slope E) of early diastolic motion of the septal mitral annulus were derived from M-mode analysis. Left heart catheterization was performed for direct measurement of LV end-diastolic pressure. Pseudonormalization defined by an E/A ratio > 1 and a LV end-diastolic pressure > or = 16 mm Hg was found in 9 patients. All patients with pseudonormalization were symptomatic (New York Heart Association class 2.8 +/- 0.5). Patients with and without pseudonormalization did not differ with respect to the E/A ratio (1.29 +/- 0.44 vs 1.16 +/- 0.23, p = NS), deceleration time (182 +/- 38 vs 205 +/- 42 ms, p = NS), and isovolumic relaxation time (88 +/- 24 vs 92 +/- 18 ms, p = NS). In the group with pseudonormalization, a significant reduction of E(M) (3.9 +/- 1.6 vs 5.7 +/- 1.5 mm, p = 0.008) and slope E (24.5 +/- 11.8 vs 43.9 +/- 7.7 mm/s, p <0.001) was detected. Using E(M) <4.3 mm and slope E <35 mm/s as cut points, sensitivity and specificity for the detection of pseudonormalization were 66% and 82% for E(M) and 77% and 87% for slope E, respectively. There was no significant relation between LV end-diastolic pressure as a measure of preload and either E(M) (r = 0.44, p >0.5) or slope E (r = 0.30, p >0.2). Thus, E(M) and slope E may be preload-independent tools for assessing LV diastolic dysfunction in symptomatic patients with a pseudonormal mitral inflow pattern and elevated filling pressures.
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[Analysis of mitral annulus excursion with tissue Doppler echocardiography (tissue Doppler echocardiography = TDE). Noninvasive assessment of left ventricular, diastolic dysfunction]. ZEITSCHRIFT FUR KARDIOLOGIE 1999; 88:353-62. [PMID: 10413858 DOI: 10.1007/s003920050297] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Mitral inflow velocity, deceleration time, and isovolumic relaxation time recorded by Doppler echocardiography have been widely used to evaluate left ventricular diastolic function but are affected by age, heart rate, loading conditions, and other factors. The diastolic mitral anulus velocity assessed by tissue Doppler echocardiography (TDE) was suggested to provide additional information about LV relaxation less affected by filling pressures. AIM OF THE STUDY This study was designed to assess the clinical utility of mitral anulus velocity in the evaluation of left ventricular diastolic function. PATIENTS AND METHODS Three groups of patients with a systolic ejection fraction > 45% were separated: 10 normal volunteers (60 +/- 10 y, CON group), 15 asymptomatic patients with known coronary artery disease (60 +/- 11 y, CAD group) and 15 patients with long-term arterial hypertension and heart failure symptoms (58 +/- 9 y, HYP group). The mitral inflow profile (E, A, E/A) was measured by pulsed Doppler, and the deceleration time (DT) and the isovolumic relaxation period (IVRT) were calculated. Systolic, early, and late diastolic velocities of the septal mitral anulus (ST, ET, AT, ET/AT) were assessed by pulsed TDE. All study subjects had invasive measurements of left ventricular end diastolic filling pressures during left heart catheterization. RESULTS In the AH group, ET (6.9 +/- 4.8 cm/s) and ET/AT (0.71 +/- 0.28) were reduced compared to the CON group (11.7 +/- 4.7 cm/s and 1.11 +/- 0.36, p < 0.05, respectively) and the CAD group (8.9 +/- 5.4 cm/s and 0.85 +/- 0.26, respectively, p = ns). The groups did not differ with respect to the mitral E/A ratio, the deceleration time and the isovolumic relaxation time. LVED in the HYP group (16 +/- 8 mm Hg) was elevated compared to the CON group (8 +/- 3, p < 0.05) and the CAD group (12 +/- 6 mm Hg, p = ns). No correlation was found between ET and LVED (r = 0.26). When the combination of mitral E/A ratio > 1 with LVED > or = 15 mm Hg was classified as pseudonormalization, the pseudonormalization could be identified by a peak early diastolic mitral anulus velocity (ET) < 7 cm/s and an ET/AT ratio < 1 with a sensitivity of 77% and a specificity of 88%. CONCLUSIONS The early diastolic mitral anulus velocity assessed by TDE (ET) is a preload-independent index of LV relaxation. TDE permits the detection of diastolic dysfunction in patients with a pseudonormal mitral inflow and elevated filling pressures.
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Abstract
Tissue Doppler echocardiography (TDE) has been shown to be of particular value in patients with impaired myocardial function. Recently, the technique was successfully employed to localize the ventricular insertion of accessory atrioventricular pathways. The identification of abnormal cardiac structures is coming up now as a new field of clinical interest. The purpose of this study was to differentiate anomalous cardiac and aortic from native structures by physical properties of tissue motion using transesophageal TDE. Characteristic motion patterns of anomalous structures have not been described in detail and tissue Doppler findings have not been associated with clinical features up to now. Forty consecutive patients were included after anomalous cardiac or vascular structures had been detected by conventional transesophageal echocardiography (TEE). A control group consisted of 20 subjects. Rapidity of diagnosis in anomalous structures was divided into 3 categories, and TDE signals were related to particular pathology by a blinded, 2nd observer. Three different motion patterns could be defined: incoherent motion due to free oscillation of an anomalous structure which is independent of the surrounding tissue (Figure 1b); coherent motion with a phase difference meaning that motion depends on the motion of the surrounding tissue but is out of phase (Figure 2); concordant motion showing no difference in direction, velocity, or phase of motion compared with the surrounding tissue. Incoherent motion was present in endocarditic vegetations, 4th degree aortic plaques, Chiari network, valvular prolapse, intracavitary tumors, and freely oscillating thrombi as well as in normal valve leaflets and papillary muscles. Especially if endocarditic vegetations are present its incoherent motion facilitates to recognize these small structures. The colorcode of this motion pattern demarcates the vegetation reliably from the surrounding tissue (Figure 1b). Within 15 seconds vegetations could be detected in 9 (82%) vs 2 (18%) patients employing only conventional imaging. Using conventional echocardiographic approaches detection of vegetations is frequently hindered by their small size and minor echo intensity (Figure 1a). In contrast, size and echo intensity do not affect the tissue Doppler signal. Normal papillary muscles and distal portions of the mitral and tricuspid valves were demonstrated to regularly meet the criterion of incoherent tissue motion in the control group. In part, this was also observed with respect to the aortic and pulmonary valves. In valvular tissue incoherent motion was caused by passive floating, whereas papillary muscles show an active inverse motion for short time intervals. Nevertheless, physiologic incoherent motion did not lead to any false differential diagnosis. The phase difference of coherent motion results from damped oscillation. This phenomenon was visualized by tissue Doppler M-mode in 5 thrombi of the left atrial appendage (LAA) (100%) and in 1 ventricular thrombus (50% of all clots). Concordant motion was shown in 3rd degree aortic plaques and postrheumatic and calcified vegetations. These structures were found to be completely embedded or closely attached, so that their passive motion corresponded to the motion of the surrounding regular tissue. Detection and assessment of anomalous structures are based on their motion patterns which can be synchronous or asynchronous in comparison with the surrounding tissue. Another goal of this investigation was to test if the sensitivity of TEE to spontaneous echo contrast can be improved using TDE. In 21 patients presenting with left atrial dilation (left atrial diameter > 44 mm) due to mitral stenosis (n = 8), mitral regurge (n = 5), arterial hypertension (n = 5) and multiple valvular disease (n = 3) fundamental multiplane TEE and transesophageal TDE were performed with standardized gain setting. The control group consisted of 20 randomized individuals with normal left
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[Asynchrony of ventricular contraction and relaxation--pathophysiologically recognized phenomenon, now can be clinically assessed]. Herz 1998; 23:506-15. [PMID: 10023585 DOI: 10.1007/bf03043758] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
When regional myocardial dysfunction is present, the physiological pattern of ventricular filling and contraction is impaired. During acute coronary occlusion, characteristic changes are observed in the ischemic myocardial segment: the amplitude of the systolic wall thickening is reduced (hypokinesia), then virtually absent (akinesia) and finally replaced by a paradoxical outward motion (dyskinesia). The maximum amplitude is reached in early diastole ("post-ejection thickening"). Since hyperkinesis develops in the normal region, the ischemic and the normal region contract asynchronously. Experimentally left ventricular asynchrony can be detected by means of subendo- and subepicardially implanted ultrasonic crystals ("sonomicrometry") or by the analysis of the phase difference of the first Fourier harmonic of dysfunctional versus control myocardial wall motion. In the clinical setting, digitized cineventriculography, radionuclide angiography and digitized M-mode echocardiography were used to assess left ventricular asynchrony in patients with coronary artery disease and hypertrophic cardiomyopathy. However, these imaging modalities are time-consuming and require complicated off-line analysis. Tissue Doppler echocardiography (TDE) is a new ultrasound modality that is based on color Doppler principles and allows for quantification of myocardial wall motion velocity by detection of consecutive phase shifts of the ultrasound signal reflected from the myocardium. The Doppler signals are displayed as a color or pulsed Doppler image by rejecting low-amplitude echoes from the blood pool due to changes in thresholding and filtering algorithms. In addition, the ability to measure low velocity is improved in the TDE system so that the lowest measurable velocity is 0.2 cm/s, a velocity level associated with cardiac tissue motion (Table 1). Due to its high temporal and spatial resolution, TDE provides valuable information on regional myocardial wall motion during different intervals of the cardiac cycle. In healthy subjects, patients with coronary artery disease and patients with hypertrophic cardiomyopathy, tissue Doppler echocardiography was used to assess myocardial synchrony/asynchrony on a 2-fold temporal and spatial analysis. Peak myocardial velocities in different myocardial regions were detected during rapid ejection, isovolumic relaxation, rapid filling and atrial contraction (Figure 1). In the apical view, during the isovolumic relaxation time (IVRT) healthy subjects showed slow, synchronous outward motion of the septum and the lateral wall with homogeneous color-encoding (blue/green, Figure 2). Analysis of peak velocities revealed low, negative velocities in both the septum and the lateral wall (Figure 3). In patients with a significant luminal narrowing of the LAD myocardial asynchrony was detected during the isovolumic relaxation period: while the septum was moving inwards (red color-encoding with low, positive velocities), the lateral wall was moving outwards (blue/green encoding, low, negative velocities). A representative example of a patient with CAD is given in Figure 4. The M-mode analysis of the abnormally contracting interventricular septum reveals positive peak tissue velocities during the isovolumic relaxation period (Figure 5). In hypertrophic cardiomyopathy, TDE was able to detect an abnormal inward motion of the interventricular septum during IVRT and a delay in the onset of rapid filling (Figure 6). Thus, tissue Doppler echocardiography is a feasible method for the on-line detection of myocardial asynchrony. Sensitivity and specificity of the findings have to be explored in further, prospectively randomized trials.
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[Aortic rupture after blunt chest trauma. Rapid diagnosis using transesophageal echocardiography when radiographic and computed tomographic findings are unclear]. Dtsch Med Wochenschr 1998; 123:244-9. [PMID: 9524534 DOI: 10.1055/s-2007-1023944] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
HISTORY AND CLINICAL FINDINGS A 37-year-old woman who was not wearing a seat-belt while driving a car had a head-on collision at 70 km/h. On arrival of the emergency physician she was awake and responsive but complained of pain with bruising over the sternum and the epigastrium. Pressure on the sternum was painful. Arterial pressure was 95/60 mm Hg, heart rate 112/min. On admission the heart sounds were unremarkable and peripheral pulses normal. Vesicular sounds were heard over both lungs. In addition to multiple facial abrasions voluntary movements were impaired and the right knee-joint was swollen. INVESTIGATIONS The ECG showed sinus tachycardia (103 beats/min) with left axis deviation, but was otherwise unremarkable. Initially the haemoglobin was 12.6 g/dl with normal white cell and platelet counts. Clotting tests, serum transaminases, creatine kinase, lactate dehydrogenase and other routine laboratory tests were within normal limits. TREATMENT AND COURSE Because the haemoglobin level had fallen to 7.7 g/dl within the first 4 hours erythrocytes concentrate was infused. The chest radiogram and subsequent computed tomography showed a mediastinal and paraaortic haematoma of unclear origin. Transoesophageal echocardiography (TEE) demonstrated rupture of the descending aorta with free floating intraluminal parts of the intima in the isthmal region, just distal to the origin of the left subclavian artery, which was not occluded. Colour Doppler echocardiography revealed abnormal flow into mediastinal and paraaortic tissues. At operation the echocardiographic findings were confirmed and part of the descending aorta was replaced by a 3 cm dacron tube during an aortic crossclamping time of 37 min. The patient was discharged after a postoperative stay of average length, during which her other injuries were treated. CONCLUSION After blunt thoracic or deceleration trauma earliest possible TEE is indicated, because it can at once provide details of extent and degree of injury to heart and/or aorta.
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MESH Headings
- Accidents, Traffic
- Adult
- Aorta, Thoracic/diagnostic imaging
- Aorta, Thoracic/injuries
- Aorta, Thoracic/surgery
- Aortic Rupture/diagnostic imaging
- Aortic Rupture/etiology
- Aortic Rupture/surgery
- Blood Vessel Prosthesis
- Blood Vessel Prosthesis Implantation
- Echocardiography, Doppler, Color
- Echocardiography, Transesophageal
- Electrocardiography
- Female
- Hematoma/diagnostic imaging
- Hematoma/etiology
- Hemoglobins/analysis
- Humans
- Mediastinal Diseases/diagnostic imaging
- Mediastinal Diseases/etiology
- Radiography, Thoracic
- Thoracic Injuries/complications
- Tomography, X-Ray Computed
- Wounds, Nonpenetrating/complications
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[Comparison of stress echocardiography and radionuclide ventriculography in the diagnosis of cardiomyopathy in patients receiving chemotherapy for malignant diseases]. Dtsch Med Wochenschr 1997; 122:1509-15. [PMID: 9453916 DOI: 10.1055/s-2008-1047793] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND AND OBJECTIVE Early evidence of drug-induced cardiomyopathy (CMP) is of great importance in haematological treatment, especially with anthracyclines. Stress echocardiography (SEC) has proved of value in determining left ventricular function at rest and under stress in patients with heart disease. The study was undertaken to assess the value of SEC in comparison with radionuclide ventriculography (RNV). PATIENTS AND METHODS 63 unselected patients with malignant tumour (20 women, 43 men; mean age 49 +/- 15 years) underwent SEC and RNV. No chemotherapy had yet been started in 17 of them, 43 had received anthracyclines as main component of the chemotherapy (mean anthracycline dose 339 +/- 251 mg/m2). Left ventricular ejection fraction (LVEF) was measured by both SEC and RNV at rest and during standardized stress (recumbent ergometry). Both methods were applied and results measured independently by two examiners. RESULTS The time interval between the two tests averaged 1 = 2 days. EC could be performed at rest in 62 of 63 and under stress in 59 of 63 patients (RNV: 63 of 63 and 54 of 63, respectively). Resting LVEF was 61 +/- 8% by SEC and 64 +/- 9% by RNV (P < 0.05). LVEF during stress, measured by SEC, was 71 +/- 11% and 73 +/- 10% by RNV (not significant). Mean LVEF increase between rest and stress was 9 +/- 10% by SEC and 9 +/- 8% by RNV (not significant). CONCLUSION SEC is a satisfactory alternative to RNV in the assessment of ventricular function in patients receiving chemotherapy. It is less involved and more cost-effective than RNV, avoids radiation exposure and provides additional information on heart size and segmental contraction abnormalities.
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[Detection of ventricular asynchrony using tissue Doppler echocardiography--a new method for assessing left ventricular wall motion]. ZEITSCHRIFT FUR KARDIOLOGIE 1997; 86:827-38. [PMID: 9454450 DOI: 10.1007/s003920050121] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
UNLABELLED The asynchrony of the heart in patients with coronary artery disease can be detected by digitized cine- and radionuclidventriculography. Both methods require time-consuming offline analysis. The aim of the current study was the assessment of the clinical value of the recently developed tissue Doppler echocardiography (TDE) to detect myocardial asynchrony. In the current study, 21 healthy subjects (age 49 +/- 14 y) and 22 patients with known coronary artery disease (20 with > 70% luminal narrowing of the LAD, 4 with a history of CABG, age 58 +/- 12 y) were included. In the apical 4-chamber-view, midseptal and midlateral LV segments were analyzed by 2-D and M-Mode-TDE. Evaluation was possible in 20 healthy subjects (95%) and 20 CAD patients (91%). During isovolumic relaxation time (IVRT) healthy subjects showed slow synchronous outward motion of the septum and the free wall with homogenous color coding (blue/green) and low negative tissue velocities followed by rapid symmetrical outward motion during rapid filling (RF) and atrial contraction (AC) phase (high negative velocities). During diatasis (DI) almost no wall motion could be detected. In 17 (85%) of 20 CAD patients, myocardial asynchrony during IVRT was detected; while the septum was moving inward (red coding with low positive velocities), the free wall was moving outward (blue green coding with low negative/velocities). After opening of the mitral valve, all CAD patients showed rapid, symmetrical outward motion of both the septum and the free wall with homogenous color coding and high negative tissue velocities. CONCLUSION Tissue Doppler echocardiography detects ventricular asynchrony online. In patients with significant LAD stenosis, a pathological septal movement is observed during isovolumic relaxation time. Determinants of the etiology could be chronic hypoperfusion or ischemia ("hibernating myocardium").
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Reproducibility of stress echocardiography using intravenous injection of ultrasound contrast agent (BY 963). INTERNATIONAL JOURNAL OF CARDIAC IMAGING 1997; 13:387-94. [PMID: 9360175 DOI: 10.1023/a:1005822920962] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
UNLABELLED Despite the widespread use of stress echocardiography, its reproducibility is still limited by high interobserver variability. Therefore, the purpose of the present study was to improve the reproducibility of a stress (exercise) echocardiography using a new transpulmonary ultrasound agent (BY 963). Stress echocardiography was performed in 12 healthy volunteers with suboptimal endocardial border delineation during exercise echocardiography. A special 45 degrees lateral tilted bike stress echocardiography table was used for exercise testing. Echocardiographic images were recorded on-line at rest and during exercise on a video tape and additionally digitized on-line on a stress echo computer. End-diastolic (EDVml), end-systolic (ESVml) volume and ejection fraction (EF%) were estimated in the 4-chamber view. The measurements were performed before and after injection of 2.5 ml and 5 ml BY963 at rest and in maximal exercise. A new contrast agent (BY 963) leads to a sufficient contrast effect for the left ventricular cavity after intravenous administration and permits a good delineation of left the endocardial border. The interobserver variability was determined using blinded investigation by two observers. The correlation of EDV and ESV determination at rest was r = 0.68/0.33, after 2.5 ml BY 963 r = 0.97/0.93 and after 5 ml BY 963 r = 0.90/0.93. The correlation for EDV and ESV during exercise was r = 0.52/0.33, after 2.5 ml BY 963 r = 0.88/0.80 and after 5 ml BY 963 r = 0.95/0.92. At rest mean EF without contrast was 61 +/- 6%/67 +/- 7% (r = 0. 130), after 2.5 ml BY 963 i.v. 69 +/- 8%/72 +/- 7% (r = 0.82) and after 5 ml BY 963 i.v. 73 +/- 8%/73 +/- 8% (r = 0.98%) respectively. In exercise, mean EF without contrast was 68 +/- 8%/70 +/- 6 (r = 0.013), after 2.5 ml BY 963 83 +/- 6%/81 +/- 5 and after 5 ml 83 +/- 4%/82 +/- 3 (r = 0.86). SUMMARY The estimation of the end-systolic volume in exercise will be improved significantly and the estimated EF values will be higher compared to EF values obtained without contrast application. Transpulmonary contrast echocardiography for analysis of left ventricular volumes and ejection fraction can be routinely used in stress echocardiography. Intravenous administration of BY 963 improves the reproducibility of quantitative analysis of left ventricular function in healthy volunteers. Further studies in patients with cardiac diseases are required to corroborate this observation.
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Abstract
Stress echocardiography is frequently used to evaluate coronary artery disease, and also in quantitative assessment of right and left ventricular function or cardiac valve integrity in patients with cardiomyopathy or during chemotherapy. Various new ultrasound techniques in stress echocardiography are now playing a significant role in this important area of cardiological diagnostics. New methods of echocardiographic signal processing have been developed to provide more quantitative and reproducible information on cardiac function during stress. The most important are: (1) raw data analysis techniques for endocardial border detection (acoustic quantification, CK = colour kinesis), (2) tissue Doppler imaging for myocardial velocity analysis and (3) transpulmonary contrast agents (Albunex, Laevovist, BY 963) for improving endocardial border delineation and for future analysis of myocardial perfusion. Like all new techniques, they must first be subjected to comprehensive scientific assessment, and appropriate training should be given, taking into account physical and physiological limits. These limits will constantly be redefined as echocardiographic techniques continue to change presenting new challenges for the further development of ultrasound technology. In this review, the improved new techniques will be discussed in detail.
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[Intensive medical monitoring with transesophageal echocardiography in fulminant pulmonary embolism]. Dtsch Med Wochenschr 1996; 121:829-33. [PMID: 8665829 DOI: 10.1055/s-2008-1043074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
HISTORY AND FINDINGS A 60-year-old man underwent a continence-preserving anterior rectal resection for a high rectal carcinoma. After mobilisation on the 5th postoperative day dyspnoea and cyanosis suddenly developed requiring emergency intubation and mechanical ventilation. INVESTIGATIONS His heart rate was 160/min, blood pressure 80/50 mmHg, mean pulmonary artery pressure by indwelling catheter was 70 mmHg. The electrocardiogram had the classical signs of acute right-heart overload. Transoesophageal echocardiography (TOE) demonstrated marked right-heart and pulmonary artery dilatation. TREATMENT AND COURSE Despite thrombolytic treatment (bolus of 50 mg r-TPA; one day later bolus of 1 million IU urokinase followed by 100,000 IU/h) a new thromboembolus was seen by TOE to straddle the pulmonary artery bifurcation. After the urokinase dosage had been raised to 200,000 IU/h TOE on the 6th day no longer showed the embolus and documented a reduction in right-heart dilatation associated with improved haemodynamics. CONCLUSION TOE is an ideal method for the rapid diagnosis and for monitoring the response to treatment of fulminant pulmonary arterial embolism. As it can also diagnose thromboembolism without significant haemodynamic consequences it is possible to adjust fibrinolytic treatment accordingly.
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[Spontaneous echo contrast in the left ventricle as an indicator for an increased risk of thromboembolism]. Dtsch Med Wochenschr 1994; 119:1317-20. [PMID: 7924930 DOI: 10.1055/s-2008-1058839] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A 69-year-old man with coronary heart disease complained of pain in his right flank. He had dyspnoea, cough and fever up to 38.8 degrees C. In addition to various positive indicators of inflammatory disease he had a creatinine concentration of 1.8 mg/dl and an increased activity of lactate dehydrogenase (1655 U/l). The chest radiograph demonstrated pneumonia and computed tomography showed an infarct in the right kidney. The ECG indicated atrial fibrillation with an irregular ventricular rate and left bundle branch block. Echocardiography demonstrated dilatation of the left ventricle and a thrombus adherent to the wall. Transoesophageal echocardiography additionally recorded spontaneous type I echo-contrast, which disappeared after therapeutic heparinization. Cerebral infarctions were shown by computed tomography, undertaken because of neurological symptoms. There were also signs of silent myocardial ischaemia. As a coronary artery bypass operation was contraindicated, percutaneous transluminal balloon angioplasty was attempted but dissection occurred, causing irreversible cardiogenic shock of which the patient died.
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Studies on the inhibitory effect of granulocytes on human granulocytopoiesis in agar cultures. Exp Hematol 1978; 6:337-45. [PMID: 648594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In the present study, the inhibitory effect of blood granulocytes on granulocytic colony formation from human white blood cells was tested. Attempts were made to clarify the effects of granulocytes by plating increasing numbers of polymorphonuclear cells (PMN) by using granulocytes which had been inactivated by freezing, by studying the effect of PMN removal and by observing the effect of dilution of granulocyte inhibitors to ineffective levels at different time intervals after the onset of culture. It will be shown that colony formation is inhibited by an excess of PMN and that the inhibitor is produced only by viable PMN. There is no inhibition during the early phase of the culture, thus suggesting that the CFU-C itself is not the target cell for the inhibition of colony formation in agar culture, but rather the more mature precursor cells of granulopoiesis.
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The role of phagocytic cells in human blood leukocyte suspensions for in vitro colony-forming cells. Exp Hematol 1978; 6:346-54. [PMID: 648595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The iron ingestion method was used to separate colony stimulating cells from in vitro colony forming cells (CFU-C) in human white blood cell (WBC) suspensions. The depletion of phagocytic cells (granulocytes and monocytes) from WBC eliminated spontaneous colony growth, without influencing the total number of CFU-C. Thus, phagocyte-free human WBC can be used as a target for measuring human colony stimulating activity (CSA). Such leukocytes can be cryopreserved, thus making possible the use of standardized target cell preparations for longitudinal studies. Hemolysate added to phagocyte-free blood leukocytes did not induce colony formation but could enhance it in the presence of a suitable CSA. Spontaneous colony formation of unseparated WBC was significantly reduced by selective destruction of granulocytes by freezing in 10% DMSO, thus indicating that both granulocytes and monocytes are involved in the production of endogenous CSA in WBC suspensions.
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Collection of in vitro colony-forming units from dogs by repeated continuous flow leukaphereses. Acta Haematol 1978; 60:172-81. [PMID: 101004 DOI: 10.1159/000207713] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The presence of in vitro colony-forming units (CFUc) was demonstrated in leukocyte suspensions collected by continuous flow leukaphereses performed serially in dogs. The CFUc yield of one leukapheresis was usually between 10(4) and 10(6). Higher yields were obtained in the 2nd to 5th leukaphereses than in the first one in the same dog. The number of CFUc collected during one leukapheresis was about four times the number of CFUc present in the circulating blood at the beginning of the leukapheresis. After a diminution during leukapheresis the circulating CFUc pool was restored in 2 or 3 days with an increase in the ratio of CFUc to mononuclear cells. These results indicate that CFUc entered the circulating pool during and after leukapheresis and that the population size regulation of canine-circulating CFUc is different from that of the bulk of the mononuclear leukoytes.
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Studies on the regeneration of the CFU-C population in blood and bone marrow of lethally irradiated dogs after autologous transfusion of cryopreserved mononuclear blood cells. SCANDINAVIAN JOURNAL OF HAEMATOLOGY 1977; 19:470-81. [PMID: 594662 DOI: 10.1111/j.1600-0609.1977.tb01503.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In a group of 8 lethally irradiated (1200 R) dogs, that were transfused autologously with cryopreserved mononuclear cells (MNC) derived from the peripheral blood by leucapheresis the concentration of colony-forming units in agar (CFU-C) in bone marrow and peripheral blood was estimated at regular intervals after irradiation and transfusion of MNC. The numbers of MNC transfused per kg body weight ranged from 0.32 x 10(9) to 1.63 x 10(9) with an incidence of CFU-C between 0.02 x 10(5) and 1.38 x 10(5). In 6 dogs the CFU-C levels in the bone marrow reached the normal pre-irradiation values between days 15 and 20. But in 2 dogs that had received the lowest CFU-C numbers the regeneration of the bone marrow CFU-C was markedly delayed. In general the time course of the bone marrow repopulation by CFU-C for single dogs was reflected by a corresponding regeneration pattern of the blood CFU-C. The time course of the curves for the blood CFU-C levels on the other hand was of the same kind as for the granulocyte values in the peripheral blood, thuations were seen in the blood CFU-C levels of single dogs before irradiation and after mononuclear leucocyte transfusion. Despite of such limitations the blood CFU-C content appeared to be a useful indicator of haematopoietic regeneration of the bone marrow.
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Cryopreservation of blood mononuclear leukocytes and stem cells suspended in a large fluid volume. A preclinical model for a blood stem cell bank. BLUT 1977; 35:195-202. [PMID: 912104 DOI: 10.1007/bf00999460] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
It was the purpose of this study to establish and evaluate a freezing-and-thawing method for preservation of hemopoietic stem cells from the peripheral blood. Blood leukocytes collected by means of an IBM Blood-Cell-Separator were frozen in plastic bags using 10% DMSO and controlled cooling rates. Thawing was performed rapidly, and DMSO was diluted and removed prior to the in-vitro and in-vivo assays. The mean recovery of mononuclear cells collected from 82 leukaphereses was 86%. To assess the recovery of cryopreserved hemopoietic stem cells, the soft agar culture method adapted for the dog was used. There was no significant difference in the CFUc recovery per 1 X 10(6) mononuclear cells or in per leukapheresis after different cryopreservation times (1--6 and 7--27 months). To evaluate the hemopoietic repopulation capability of cryopreserved blood stem cells, leukapheresis-derived leukocytes were transfused into 1200 R whole body x-irradiated dogs. The hemopoietic repopulation pattern at day 10 after transfusion of comparable numbers of fresh or frozen leukocytes was not significantly different, as measured in bone marrow smears and sections and by granulocyte concentration in the peripheral blood.
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A discussion: laparoscopic instrument sterilization. MEDICAL INSTRUMENTATION 1977; 11:122-3. [PMID: 140291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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The repopulation of lymph nodes of dogs after 1200 R whole-body x-irradiation and intravenous administration of mononuclear blood leukocytes. THE AMERICAN JOURNAL OF PATHOLOGY 1976; 84:259-82. [PMID: 941979 PMCID: PMC2032449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Fresh and cryopreserved autologous or allogeneic mononuclear blood cells (MBCs) intravenously injected in 1200 R total-body x-irradiated dogs repopulated lymph nodes within 10 days after tranfusion. Several parameters of the lymphopoietic regeneration were correlated with the number of cells transfused and with the number of colony-forming units contained in the cell suspension when they were cultured in agar (CFUc). Values within the normal or close to normal range were reached in the mesenteric nodes of most of the animals transfused with 10 X 10(9) MBC or more. These values were obtained when 5 X 10(5) CFUc or more were transfused. Axillary nodes showed lower values than mesenteric nodes. They were mostly under the normal range but well over those of the irradiated controls. Frozen and thawed MBCs seem to be as effective as fresh cells for lymphopoietic restoration. The mesenteric nodes of dogs transfused with allogeneic MBCs showed higher cellularity and larger cortical-paracortical areas than those of dogs tranfused with approximately the same number of autologous cells. The repopulation of lymph nodes parallels that of the marrow.
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Treatment of aplastic anemia by blood stem cell transfusion: a canine model. Haematologica 1976; 61:141-56. [PMID: 7516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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Regeneration of blood-forming organs after autologous leukocyte transfusion in lethally irradiated dogs. II. Distribution and cellularity of the marrow in irradiated and transfused animals. Blood 1976; 47:593-601. [PMID: 1260123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Dogs were given transfusions of cryopreserved autologous mononuclear blood leukocytes after 1200 roentgens (R) (midline dose) whole-body x-irradiation. Bone marrow repopulation was studied by means of histomorphological methods at days 9 and 10 after transfusion of an average of 3 X 10(9), 7 X 10(9), 13 X 10(9), and 31 X 10(9) cells. The return of marrow cellularity to normal values was related to the number of cells transfused. With low cell doses (3 X 10(9) and 7 X 10(9)), the marrow regeneration at 10 days was focal. There were groups of cells (colonies) showing either erythropoiesis, myelopoiesis, or megakaryocytopoiesis in the osteal niches of the trabecular bones. Frequently such niches were seen showing complete cellular recovery next to niches with complete aplasia. With higher cell doses, all niches showed hemopoietic regeneration, and the cellularity approached normal values. No hemopoietic regeneration was observed in those skeletal parts that do not show hemopoiesis, even under normal circumstances.
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Colony formation by canine hemopoietic cells in vitro. Inhibition by polymorphonuclear leukocytes. Acta Haematol 1976; 56:107-15. [PMID: 823755 DOI: 10.1159/000207926] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In soft agar cultures of canine blood leukocytes, an inhibition of colony formation was observed relative to the size of the inoculum. Analysis of the cellular composition of the inoculum suggested that this inhibition was associated with the number of polymorphonuclear leukocytes present. Removal of phagocytic cells by the iron ingestion method or selective destruction of granulocytes by freezing in the presence of dimethyl sulfoxide eliminated the inhibitory action on colony formation. In mixed cultures of canine bone marrow and antologous blood leukocytes, a similar inhibition of colony formation was observed. The results presented indicate that polymorphonuclear leukocytes, if present in a concentration exceeding 2.5X10(6)/ml of inoculum, inhibit in vitro granulocytic/monocytic colony formation.
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