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1.
Chest ; 114(2): 477-81, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9726733

RESUMO

OBJECTIVES: This study was designed to observe left ventricular filling by Doppler echocardiography before and after single lung transplantation in patients with severe pulmonary hypertension. BACKGROUND: Right ventricular pressure overload causes the deformation of the left ventricle by septal flattening toward its cavity, which may result in impaired left ventricular early filling. Recent studies have demonstrated the ability of single lung transplantation to restore right ventricular function in patients with severe pulmonary hypertension. However, changes in left ventricular filling after single lung transplantation have not been well studied. METHODS: We performed Doppler echocardiography in nine patients with severe pulmonary hypertension before, early (<3 months), and late (>1 year) after single lung transplantation. The study group consisted of eight female patients and one male patient with mean age of 32 years (range, 15 to 48 years). Six patients were diagnosed as having primary pulmonary hypertension and three as having secondary pulmonary hypertension. Nine age-matched normal subjects served as a control group. Doppler measurements included the following: transmitral flow early (E) and atrial (A) velocities, integrals (Ei and Ai), and left ventricular isovolumic relaxation time. The ratio of E/A and atrial filling fraction (Ai/Ei+Ai, AFF) were also determined. Left ventricular geometry was assessed from mid-short axis view with a circular shape factor (CSF). RESULTS: Early after lung transplantation, the left ventricular geometry became more circular with CSF (mean+/-SD) increasing from 0.63+/-0.09 to 0.88+/-0.05 (p<0.05). However, impaired early filling persisted in the patient group (E/A 0.7+/-0.1 vs preoperative 0.6+/-0.1, AFF 0.61+/-0.1 vs 0.64+/-0.1; both p=not significant). One year later, the left ventricular filling had returned to normal range with E/A 1.4+/-0.6 and AFF 0.35+/-0.1. CONCLUSIONS: This study observed that the impaired left ventricular early filling persisted shortly after single lung transplantation in patients with severe pulmonary hypertension, despite findings that left ventricular geometry was restored earlier after reversal of pulmonary hypertension. The abnormal filling pattern appeared to be resolved 1 year later. The findings suggest the impaired early filling may be caused by intrinsic left ventricular abnormalities other than ventricular interaction in these patients.


Assuntos
Hipertensão Pulmonar/fisiopatologia , Transplante de Pulmão , Função Ventricular Esquerda , Adolescente , Adulto , Velocidade do Fluxo Sanguíneo , Diástole , Ecocardiografia Doppler , Feminino , Seguimentos , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/cirurgia , Masculino , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem , Valva Mitral/fisiopatologia , Contração Miocárdica , Estudos Retrospectivos , Resultado do Tratamento , Pressão Ventricular
2.
Int J Card Imaging ; 14(1): 47-53, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9559378

RESUMO

The relation of transmitral flow patterns and pulmonary venous velocities was analyzed from 50 heart failure patients (28 men, 22 women; mean [+/- SD] age 61 +/- 9 years) with a left ventricular ejection fraction < 40%. Doppler echocardiography was performed in all patients. Transmitral flow measurements included early (E) and atrial (A) velocities and deceleration time of E wave (DT). Patients were assigned to two groups according to E/A ratio, DT, or both: 20 patients in the restrictive group, and 30 patients in the nonrestrictive group. Pulmonary venous flow was obtained by the transthoracic approach. Systolic (S), diastolic (D) and atrial reversal (Ar) velocities were measured. Of the study population, 13 patients had simultaneously determined pulmonary capillary wedge pressure (PCWP). The results showed a lower S (28 +/- 11 vs. 51 +/- 10 cm/sec, p < 0.01), a higher D (66 +/- 13 vs. 44 +/- 10 cm/sec, p < 0.01) and a smaller Ar (12 +/- 10 vs. 24 +/- 9 cm/sec, p < 0.01) in the restrictive group compared with those in nonrestrictive group. In the subgroup of patients undergoing invasive hemodynamic studies, there was no relationship between PCWP and atrial reversal velocity. However, a significant correlation was observed for pulmonary systolic (r = -0.70, p < 0.01) and diastolic (r = 0.76, p < 0.01) velocities to PCWP. These findings suggest a reduction in left atrial compliance and atrial systolic function and both play important roles in heart failure patients with the restrictive transmitral flow pattern.


Assuntos
Função do Átrio Esquerdo/fisiologia , Ecocardiografia Transesofagiana/métodos , Insuficiência Cardíaca/diagnóstico por imagem , Veias Pulmonares/diagnóstico por imagem , Idoso , Velocidade do Fluxo Sanguíneo , Ecocardiografia Doppler , Feminino , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Veias Pulmonares/fisiopatologia , Pressão Propulsora Pulmonar , Sensibilidade e Especificidade , Volume Sistólico
3.
J Am Coll Cardiol ; 30(3): 802-10, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9283544

RESUMO

OBJECTIVES: We sought to validate freehand three-dimensional echocardiography for measuring left ventricular mass and to compare its accuracy and variability with those of conventional echocardiographic methods. BACKGROUND: Accurate measurement of left ventricular mass is clinically important as a predictor of morbidity and mortality. Freehand three-dimensional echocardiography eliminates geometric assumptions used by conventional methods, minimizes image positioning errors using a line of intersection display and increases sampling of the ventricle. Preliminary studies have shown it to have high accuracy and low variability. METHODS: Twenty-eight patients awaiting heart transplantation were examined by conventional and freehand three-dimensional echocardiography. Left ventricular mass was determined by the M-mode ("Penn-cube") method, the two-dimensional truncated ellipsoid method and three-dimensional surface reconstruction. The ventricles of 20 explanted hearts were obtained, trimmed and weighed. Echocardiographic mass by each method was compared with true mass by linear regression. Accuracy, bias and interobserver variability were calculated. RESULTS: For three-dimensional echocardiography, the correlation coefficient, standard error of the estimate, root mean square percent error (accuracy), bias and interobserver variability were 0.992, 11.9 g, 4.8%, -4.9 g and 11.5%, respectively. For the two-dimensional truncated ellipsoid method they were 0.905, 38.5 g, 15.6%, 15.4 g and 23.3%. For the M-mode ("Penn-cube") method they were 0.721, 96.9 g, 53.0%, 109.2 g and 19.5%. CONCLUSIONS: Freehand three-dimensional echocardiography for measurement of left ventricular mass has high accuracy and low variability and is superior to conventional methods in hearts of abnormal size and geometry.


Assuntos
Ecocardiografia Tridimensional , Ventrículos do Coração/anatomia & histologia , Ventrículos do Coração/diagnóstico por imagem , Adulto , Feminino , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Tamanho do Órgão , Reprodutibilidade dos Testes
4.
J Am Soc Echocardiogr ; 10(5): 588-92, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9203503

RESUMO

A young woman without symptoms underwent repair of an ostium secundum atrial septal defect, and exertional dyspnea developed postoperatively. This was found to be due to arterial oxygen desaturation which was exaggerated in the upright position and with exercise. Contrast echocardiography confirmed a right-to-left shunt at the atrial level that was shown only with femoral venous contrast injection and not with upper extremity venous injection. Transesophageal echocardiography and subsequent surgical exploration found that the Eustachian valve had been mistaken for the inferior rim of the defect and sutured to the upper rim of the defect. This created a channel through which blood from the inferior vena cava could be partially deferred to the left atrium.


Assuntos
Ecocardiografia Transesofagiana , Comunicação Interatrial/cirurgia , Erros Médicos , Oxigênio/sangue , Complicações Pós-Operatórias , Adulto , Dispneia/etiologia , Feminino , Átrios do Coração/diagnóstico por imagem , Comunicação Interatrial/sangue , Comunicação Interatrial/diagnóstico por imagem , Humanos , Esforço Físico , Postura
6.
J Am Coll Cardiol ; 27(7): 1761-70, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8636566

RESUMO

OBJECTIVES: This study was designed to compare the accuracy of three- and two-dimensional echocardiography for quantifying the extent of abnormal wall motion in experimental acute myocardial infarction, as correlated with the pathologic determination of infarct size. BACKGROUND: Two-dimensional echocardiographic estimations of the fraction of myocardium showing abnormal wall motion are often used as an index of infarct size even though they rely on image plane positioning and geometric assumptions that may not be valid. Three-dimensional echocardiographic reconstruction of the endocardial surface eliminates the need for these assumptions and may improve echocardiographic estimates of infarct size. METHODS: Coronary ligation was performed in 14 open chest dogs, and echocardiographic imaging of the ventricle was performed 6 h later. Three-dimensional echocardiography used seven or eight spatially registered short-axis images to measure percent of endocardial surface and mass showing abnormal wall motion. Three two-dimensional echocardiographic methods using multiple, nonpatially registered images were evaluated. One method used seven or eight-axis slices and a summation of discs algorithm for computing surface area. The second method used the same images and a conical model for the left ventricle. The third used basal, middle and apical short-axis plus apical four- and two-chamber views comparing summed endocardial lengths showing abnormal wall motion with the total of the endocardial dimensions, expressed as percent. The percent of left ventricular mass and surface area infarcted was determined by staining with triphenyltetrazolium chloride. RESULTS: Three-dimensional echocardiographic measurements of endocardial surface and correlated more closely with infarct mass (r = 0.94, SEE +/- 3.6%) than did the two-dimensional method using the summation of discs algorithm (r = 0.85, SEE +/- 6.6%), he summation of conical sections algorithm (r = 0.82, SEE +/- 5.4%) or the method using summed endocardial lengths (r = 0.79, SEE +/- 7.4%). Limits of agreement analysis comparing mass showing abnormal wall motion with anatomic infarct mass surface area showing abnormal wall motion with anatomic infarct surface area showed the smallest limits for three-dimensional echocardiography. CONCLUSIONS: Three-dimensional echocardiography is a more accurate means of noninvasively estimating myocardial infarct size in this canine model than two-dimensional echocardiography.


Assuntos
Ecocardiografia/métodos , Contração Miocárdica , Infarto do Miocárdio/diagnóstico por imagem , Animais , Cães , Estudos de Avaliação como Assunto , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia
7.
Am J Hypertens ; 9(5): 467-74, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8735178

RESUMO

A three-dimensional echocardiographic system has been developed that can accurately compute left ventricular mass in vitro. This study was designed to validate the new echocardiographic system for the measurement of left ventricular mass in vivo and to compare the accuracy of three-dimensional echocardiography to the accuracy of conventional two-dimensional echocardiography for measuring left ventricular mass. Echocardiographic imaging was performed 6 h following coronary ligation in 20 open chest dogs, at which time the heart was excised and the left ventricle weighed. Three-dimensional echocardiography used multiple short axis sections and polyhedral surface reconstruction to compute myocardial volume. The two dimensional methods employed the truncated ellipsoid model and the area-length model. Myocardial volume was multiplied by 1.05 g/cc and echocardiographic mass estimates were compared to the true left ventricular weight. Three-dimensional echocardiography provided the best correlation (r = 0.96, upsilon r = 0.88 and r = 0.83 for the truncated-ellipsoid and area-length methods, respectively), and the lowest standard error of the estimate for the regression equation (+/- 5.5 g upsilon +/- 11.0 and +/- 14.6 g, respectively). Three dimensional echocardiography also had the lowest standard deviation for the echo-true mass differences (+/- 5.8 g upsilon +/- 10.7 g and +/- 14.2 g) and a lower root mean square percent error (6.8%) upsilon 12.6% and 12.7%). In this open chest canine model, three-dimensional echocardiography is more accurate than standard two-dimensional echocardiographic methods for measuring left ventricular mass.


Assuntos
Ecocardiografia , Coração/anatomia & histologia , Função Ventricular Esquerda/fisiologia , Animais , Cães , Ventrículos do Coração/anatomia & histologia , Ventrículos do Coração/diagnóstico por imagem , Análise de Regressão
8.
Echocardiography ; 12(6): 559-69, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10158100

RESUMO

An echocardiographic system has been developed that performs automatic endocardial border detection and instantaneously calculates and displays a waveform of left ventricular cavity area versus time. The purpose of this study was to compare measurements of left ventricular filling dynamics from automatic border detection echocardiography with similar measurements from cineventriculography. Thirty-three patients undergoing cardiac catheterization had automatic border detection echocardiography performed within 45 minutes of cineventriculography. Ten patients had normal catheterization findings and 23 had cardiac disease. The automatic border detection waveforms generated from two echocardiographic views were measured to determine the fraction of filling occurring during the early diastolic rapid filling phase and during the filling phase resulting from atrial contraction. Similar fractions were derived from curves generated from frame-by-frame measurements of cineangiographic volumes. Results were analyzed by correlating echocardiographic and cineventriculographic results, and by a limits of agreement analysis (limits of agreement were +/- 2 standard deviations of the mean difference between echocardiography and cineventriculography). There were significant correlations between echocardiography and cineventriculography for each of the parameters studied. The best results were obtained for the apical four-chamber view (rapid filling fraction r = 0.72, P < 0.0001, atrial filling fraction r = 0.56, P < 0.001). Differences in filling patterns between normal and abnormal patient groups detected by cineventriculography were also detected by automatic border detection echocardiography. However, broad limits of agreement were observed, that may limit the ability of the automatic border detection system to reliably predict cineventriculographic results in an individual patient. Automatic border detection echocardiography can provide information about left ventricular filling dynamics that is similar to that obtained from frame-by-frame analysis of cineventriculograms. However, the variability in the results may limit the application of the technique in individual patients.


Assuntos
Algoritmos , Volume Cardíaco/fisiologia , Dor no Peito/diagnóstico por imagem , Função Ventricular Esquerda , Adulto , Idoso , Cateterismo Cardíaco , Cinerradiografia/métodos , Ecocardiografia/métodos , Feminino , Hemodinâmica , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Função Ventricular Esquerda/fisiologia
9.
J Electrocardiol ; 28(4): 313-21, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8551174

RESUMO

The authors previously postulated that a markedly downsloping PR-segment might be a marker for exaggerated atrial repolarization waves and demonstrated PR-segment appearance to be an independent predictor of a false positive exercise test. This study was conducted to determine the sensitivity, specificity, and predictive value of markedly downsloping PR-segments for predicting false positive exercise tests. The study group consisted of 82 consecutive patients with a positive exercise test (> or = 1.0 mm horizontal ST depression) and a normal resting electrocardiogram. Tests were predicted to be false positive based on previously defined criteria: (1) markedly downsloping PR-segments in two or more of leads II, III, and aVF and (2) exercise duration 4 minutes or longer. Patients were then classified according to available clinical information (coronary angiography and radionuclide stress testing) into true positive (due to myocardial ischemia, n = 62) and false positive (n = 20) groups. The sensitivity, specificity, and predictive value of the PR-segment/exercise duration criterion for predicting a false positive test were 70, 74, and 47%, respectively. Patients with false positive tests also had higher heart rates (158 +/- 16 vs 136 +/- 20 beats/min, P < .001) and less frequent chest pain (15 vs 46%, P = .017) during the exercise test. Patients with false positive exercise tests can be recognized by the achievement of a high peak exercise heart rate, the absence of exercise-induced chest pain, and the appearance of markedly downsloping PR-segments in the inferior leads.


Assuntos
Função Atrial/fisiologia , Eletrocardiografia , Teste de Esforço , Isquemia Miocárdica/diagnóstico , Cateterismo Cardíaco , Estudos de Casos e Controles , Reações Falso-Positivas , Feminino , Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/epidemiologia , Variações Dependentes do Observador , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Radioisótopos de Tálio , Fatores de Tempo , Ventriculografia de Primeira Passagem
10.
J Am Soc Echocardiogr ; 8(5 Pt 1): 576-84, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-9417199

RESUMO

A new three-dimensional echocardiographic system creates a "line of intersection" display to allow precise and known positioning of echocardiographic images. Our purpose was to determine whether use of the line-of-intersection display will improve positioning of the apical four-chamber and apical two-chamber views and thereby improve the agreement between estimates of left ventricular volume by apical biplane echocardiography and cineventriculography. Unguided and line of intersection-guided apical biplane views were obtained in 31 patients immediately before cardiac catheterization and single-plane cineventriculography. In 15 patients the line-of-intersection display was used to measure the position of the image plane in studies of unguided and guided methods. Linear regression and limits of agreement analysis were used to assess the agreement between cineventriculographic volumes and echocardiographic volumes determined from each set of images. The Wilcoxon test was used to compare guided and unguided image positioning. The line-of-intersection display improved four-chamber and two-chamber view positioning closer to the center of the ventricle and rotation closer to orthogonal positioning. Guided-image positioning was not able to correct displacement of the ultrasound beam anterior to the ventricular apex without deterioration of image quality in most patients. Despite improvements in image plane positioning, the agreement between echocardiographic and cineventriculographic volumes was unchanged. For end-diastole views, the unguided images had an r value = 0.84, standard error of the estimate of +/- 23.0 cc, and limits of agreement of +/- 62.4 cc. Corresponding values for the guided images at end diastole were r = 0.85, standard error of the estimate of +/- 22.9 cc, and limits of agreement of +/- 60.8 cc. At end systole the unguided results were r = 0.91, standard error of the estimate of 16.8 cc, and limits of agreement of +/- 52.2 cc. The line-of-intersection guiding of image plane positioning can improve apical image positioning but does not improve the agreement between apical biplane echocardiographic and cineventriculographic left ventricular volumes. The optimal apical imaging window is frequently occluded by the rib cage, resulting in a decrease in image quality. This reduction of image quality, combined with assumptions of left ventricular geometry, limit the accuracy of estimates of left ventricular volume from apical biplane echocardiography.


Assuntos
Volume Cardíaco , Ecocardiografia/métodos , Holografia/métodos , Função Ventricular Esquerda , Adulto , Idoso , Viés , Cinerradiografia , Meios de Contraste , Apresentação de Dados , Diástole , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Aumento da Imagem/métodos , Iohexol , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica , Rotação , Sístole
11.
Circulation ; 92(4): 842-53, 1995 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-7641365

RESUMO

BACKGROUND: Reliable, serial, noninvasive quantitative estimation of left ventricular ejection fraction is essential for selecting and timing therapeutic interventions in patients with heart disease. Equilibrium radionuclide angiography is widely used for this purpose but has well-recognized limitations. Advantages of echocardiography over equilibrium radionuclide angiography include assessment of wall motion, valvular pathology, and cardiac hemodynamics, in addition to portability, lack of radiation exposure, and substantially lower cost. However, conventional echocardiographic techniques are limited by geometric assumptions, image positioning errors, and use of subjective visual methods. To overcome these limitations, a three-dimensional echocardiographic method was developed. This study compares ejection fraction by three-dimensional echocardiography, quantitative two-dimensional echocardiography, and subjective two-dimensional echocardiographic visual estimation with that by equilibrium radionuclide angiography. METHODS AND RESULTS: Fifty-one unselected patients with suspected heart disease underwent left ventricular ejection fraction determination by equilibrium radionuclide angiography and three-dimensional echocardiography using an interactive line-of-intersection display and a new algorithm, ventricular surface reconstruction, for volume computation. In 44 patients, ejection fractions were also estimated visually by experienced observers from two-dimensional echocardiography and by quantitative two-dimensional echocardiography using an apical biplane summation-of-disks algorithm. An excellent correlation was obtained between three-dimensional echocardiography and equilibrium radionuclide angiography (r = .94 to .97, SEE = 3.64% to 5.35%; limits of agreement, 10.3% to 13.3%) without significant underestimation or overestimation. SEE values and limits of agreement were twofold to threefold lower than corresponding values for all two-dimensional echocardiographic techniques. In addition, interobserver variability was significantly lower for the three-dimensional echocardiographic method (10.2%) than for the apical biplane summation-of-disks method (26.1%) and subjective visual estimation (33.3%). CONCLUSIONS: Determination of ejection fraction by three-dimensional echocardiography yields results comparable to those obtained by equilibrium radionuclide angiography and is substantially superior to all two-dimensional echocardiographic methods. Therefore, three-dimensional echocardiography may be used for accurate serial quantification of left ventricular function as an alternative to equilibrium radionuclide angiography.


Assuntos
Ecocardiografia , Coração/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Ecocardiografia/métodos , Feminino , Coração/diagnóstico por imagem , Testes de Função Cardíaca , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Angiografia Cintilográfica , Volume Sistólico , Função Ventricular Esquerda
12.
N Engl J Med ; 332(6): 356-62, 1995 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-7823997

RESUMO

BACKGROUND: Rupture of the aorta is a major cause of death after motor vehicle accidents. Survival depends on early diagnosis, and emergency aortography is the standard imaging method. Although transesophageal echocardiography is noninvasive and can provide high-resolution images of the aorta, information about its value in patients with trauma is limited. We conducted this study to assess prospectively the value of transesophageal echocardiography in the emergency evaluation of patients at risk for aortic injury. METHODS: Transesophageal echocardiography of the aorta was attempted in 101 patients admitted to the emergency room with a diagnosis of possible traumatic rupture of the aorta. Echocardiography and aortography personnel were notified simultaneously of the arrival of the patient, and the two tests were performed sequentially by operators who were blinded to the results of the other test. The sensitivity and specificity of transesophageal echocardiography were calculated on the basis of the results of aortography of the arch, surgery, or autopsy. RESULTS: Transesophageal echocardiography was attempted in 101 patients. The study was successfully performed in 93 patients but could not be completed in 8 because of lack of cooperation on the part of the patient (7 patients) or maxillofacial trauma (1 patient). Despite a high injury-severity score (mean, 29.6), transesophageal echocardiography was performed without complications, and within a mean (+/- SD) of 29 +/- 12 minutes. Eleven of the 93 studies (12 percent) demonstrated rupture of the aorta near the isthmus. The findings were confirmed in 10 of the 11 patients by aortography (9 patients), surgery (9 patients), or autopsy (1 patient), yielding a sensitivity of 100 percent and specificity of 98 percent for the detection of injury to the aorta. There was one false positive echocardiogram. CONCLUSIONS: Transesophageal echocardiography is a highly sensitive and specific method of detecting injury to the thoracic aorta. This technique can be used safely and quickly in critically injured patients with suspected traumatic rupture of the aorta and compares favorably with arch aortography.


Assuntos
Aorta Torácica/diagnóstico por imagem , Aorta Torácica/lesões , Ruptura Aórtica/diagnóstico por imagem , Ecocardiografia Transesofagiana , Doença Aguda , Adulto , Idoso , Aortografia , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Ferimentos não Penetrantes/complicações
14.
J Trauma ; 37(6): 989-95, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7996617

RESUMO

This prospective study sought to further define the role of transesophageal echocardiography (TEE) in diagnosing thoracic aortic injury. We performed TEE, aortography, or both on 160 consecutive patients suspected of having blunt thoracic aortic injury: TEE correctly identified 14 aortic injuries, of which five were confirmed by aortography, seven at thoracotomy, and two at autopsy. The TEE results were suggestive of but not diagnostic for injury in two additional patients with proven aortic injury, and TEE was otherwise 100% sensitive and specific for aortic injury. Aortograms yielded one false positive result and four false negative results, for a sensitivity of 73% and a specificity of 99%. We conclude that TEE is a rapid, safe, and accurate bedside method for evaluating the heart and thoracic aorta for blunt trauma. Negative or positive TEE results obviate the need for aortography. We recommend that aortography be used when TEE results are equivocal, when TEE is not tolerated or contraindicated, or when other suspected vascular injuries require evaluation by arteriography.


Assuntos
Aorta Torácica/lesões , Ecocardiografia Transesofagiana , Ferimentos não Penetrantes/complicações , Adulto , Idoso , Algoritmos , Aortografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
15.
J Am Coll Cardiol ; 24(4): 1054-63, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7930197

RESUMO

OBJECTIVES: We compared two- and three-dimensional echocardiography with cineventriculography for measurement of left ventricular volume in patients. BACKGROUND: Three-dimensional echocardiography has been shown to be highly accurate and superior to two-dimensional echocardiography in measuring left ventricular volume in vitro. However, there has been little comparison of the two methods in patients. METHODS: Two- and three-dimensional echocardiography were performed in 35 patients (mean age 48 years) 1 to 3 h before left ventricular cineventriculography. Three-dimensional echocardiography used an acoustic spatial locator to register image position. Volume was computed using a polyhedral surface reconstruction algorithm based on multiple nonparallel, unevenly spaced short-axis cross sections. Two-dimensional echocardiography used the apical biplane summation of disks method. Single-plane cineventriculographic volumes were calculated using the summation of disks algorithm. The methods were compared by linear regression and a limits of agreement analysis. For the latter, systematic error was assessed by the mean of the differences (cineventriculography minus echocardiography), and the limits of agreement were defined as +/- 2 SD from the mean difference. RESULTS: Three-dimensional echocardiographic volumes demonstrated excellent correlation (end-diastole r = 0.97; end-systole r = 0.98) with cineventriculography. Standard errors of the estimate were approximately half of those of two-dimensional echocardiography (end-diastole +/- 11.0 ml vs. +/- 21.5 ml; end-systole +/- 10.2 ml vs. +/- 17.0 ml). By limits of agreement analysis the end-diastolic mean differences for two- and three-dimensional echocardiography were 21.1 and 12.9 ml, respectively. The limits of agreement (+/- 2 SD) were +/- 54.0 and +/- 24.8 ml, respectively. For end-systole, comparable improvement was obtained by three-dimensional echocardiography. Results for ejection fraction by the two methods were similar. CONCLUSIONS: Three-dimensional echocardiography correlates highly with cineventriculography for estimation of ventricular volumes in patients and has approximately half the variability of two-dimensional echocardiography for these measurements. On the basis of this study, three-dimensional echocardiography is the preferred echocardiographic technique for measurement of ventricular volume. Three-dimensional echocardiography is equivalent to two-dimensional echocardiography for measuring ejection fraction.


Assuntos
Volume Cardíaco , Cineangiografia , Ecocardiografia , Ventrículos do Coração/diagnóstico por imagem , Função Ventricular Esquerda , Adulto , Idoso , Cateterismo Cardíaco , Ecocardiografia/métodos , Feminino , Cardiopatias/fisiopatologia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Análise de Regressão
16.
J Am Coll Cardiol ; 24(2): 504-13, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8034889

RESUMO

OBJECTIVES: This study aimed to validate a method for mass computation in vitro and in vivo and to compare it with conventional methods. BACKGROUND: Conventional echocardiographic methods of determining left ventricular mass are limited by assumptions of ventricular geometry and image plane positioning. To improve accuracy, we developed a three-dimensional echocardiographic method that uses nonparallel, nonintersecting short-axis planes and a polyhedral surface reconstruction algorithm for mass computation. METHODS: Eleven fixed hearts were imaged by three-dimensional echocardiography, and mass was determined in vitro by multiplying the myocardial volume by the density of each heart and comparing it with the true mass. Mass at diastole and systole by three-dimensional echocardiography and magnetic resonance imaging (MRI) was compared in vivo in 15 normal subjects. Ten subjects also underwent imaging by one- and two-dimensional echocardiography, and mass was determined by Penn convention, area-length and truncated ellipsoid algorithms. RESULTS: In vitro results were r = 0.995, SEE 2.91 g, accuracy 3.47%. In vivo interobserver variability for systole and diastole was 16.7% to 27%, 14% to 18.1% and 6.3% to 12.8%, respectively, for one-, two- and three-dimensional echocardiography and was 7.5% for MRI at end-diastole. The latter two agreed closely with regard to diastolic mass (r = 0.895, SEE 11.1 g) and systolic mass (r = 0.926, SEE 9.2 g). These results were significantly better than correlations between MRI and the Penn convention (r = 0.725, SEE 25.6 g for diastole; r = 0.788, SEE 28.7 g for systole), area-length (r = 0.694, SEE 24.2 g for diastole; r = 0.717, SEE 28.2 g for systole) and truncated ellipsoid algorithms (r = 0.687, SEE 21.8 g for diastole; r = 0.710, SEE 24.5 g for systole). CONCLUSIONS: Image plane positioning guidance and elimination of geometric assumptions by three-dimensional echocardiography achieve high accuracy for left ventricular mass determination in vitro. It is associated with higher correlations and lower standard errors than conventional methods in vivo.


Assuntos
Ecocardiografia/métodos , Ventrículos do Coração/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Adulto , Algoritmos , Feminino , Ventrículos do Coração/anatomia & histologia , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico , Processamento de Imagem Assistida por Computador , Técnicas In Vitro , Imageamento por Ressonância Magnética , Masculino , Análise de Regressão
17.
Hypertension ; 23(1 Suppl): I172-9, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8282353

RESUMO

There is a need for more accurate and reproducible serial measurement of left ventricular volume and mass in individual subjects by echocardiography. Conventional echocardiography has significant measurement variability because of its use of geometric assumptions and image plane positioning errors. Guided three-dimensional echocardiography eliminates geometric assumptions and reduces image plane positioning errors by using a "line of intersection" display. Use of three-dimensional guided imaging for a one-dimensional measurement of the left ventricle resulted in a threefold improvement of interobserver variability over conventional echocardiographic measurements. Computer-aided three-dimensional reconstruction of the ventricle for ventricular volume from a series of 8 to 10 short-axis images also achieved more than a threefold improvement of interobserver variability compared with two-dimensional echocardiography. Three-dimensional echocardiographic computation of ventricular volume and mass in healthy subjects was achieved with an accuracy comparable to magnetic resonance imaging and was superior to two-dimensional echocardiography. Three-dimensional echocardiography promises to be a more accurate method of estimating left ventricular volume and mass and may be suitable for serial study of individual subjects because of its improved accuracy and decreased interobserver variability compared with conventional echocardiographic methods.


Assuntos
Ecocardiografia Doppler/métodos , Ecocardiografia/métodos , Ventrículos do Coração/anatomia & histologia , Coração/anatomia & histologia , Diástole , Humanos , Imageamento por Ressonância Magnética/métodos , Valores de Referência , Análise de Regressão , Sístole
18.
J Am Coll Cardiol ; 22(7): 1816-20, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8245334

RESUMO

OBJECTIVES: This study was conducted to determine the diagnostic yield and risks of a symptom-limited treadmill exercise test before hospital discharge. BACKGROUND: Currently, predischarge low level and 6-week symptom-limited exercise treadmill tests are recommended for risk stratification after myocardial infarction. However, few data exist on the safety and value of a predischarge symptom-limited exercise test. METHODS: We utilized a modified Bruce protocol starting at 1.7 mph and 0 grade with 3-min stages in 150 consecutive patients 6.4 +/- 3.1 days after myocardial infarction. Each exercise test was interpreted for duration, symptoms and ST segment changes at the low level (70% of predicted heart rate) and symptom-limited end point. RESULTS: There were no complications related to the symptom-limited exercise tests. The test results were positive in only 23% of the patients at the low level end point, but were positive in 40% of the patients at the later symptom-limited end point (p < 0.001). During a mean follow-up period of 15 +/- 5 months in 138 patients (92%), 50 patients (36%) had a cardiac event. Of the patients with a cardiac event, significantly more (p < 0.001) had a positive exercise test at the symptom-limited end point (31 vs. 16 patients). Five patients with a negative and 14 patients with a nondiagnostic symptom-limited exercise test had an event. CONCLUSIONS: In patients with uncomplicated myocardial infarction, we demonstrated the safety of an early symptom-limited treadmill exercise test. Symptom-limited exercise tests will identify more patients with inducible ischemia who are at risk of future cardiac events and who may benefit from early intervention.


Assuntos
Eletrocardiografia , Teste de Esforço , Tolerância ao Exercício/fisiologia , Infarto do Miocárdio/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Valor Preditivo dos Testes , Fatores de Risco , Segurança , Fatores de Tempo
19.
J Am Coll Cardiol ; 22(5): 1530-7, 1993 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-8227815

RESUMO

OBJECTIVES: This study was designed to compare three-dimensional echocardiography, two-dimensional echocardiography and cineventriculography for the purpose of measuring left ventricular volume in vitro. BACKGROUND: Three-dimensional echocardiographic systems have been shown to be highly accurate in measuring the volumes of balloon phantoms. However, three-dimensional techniques have not been compared with standard two-dimensional echocardiography in vitro or with cineventriculography, the clinical standard for left ventricular volume measurement. METHODS: Excised porcine hearts were prepared with an internal latex sheath that could be filled and maintained with a known ("true") volume of liquid. Each heart was then imaged by cineventriculography, standard two-dimensional echocardiography and three-dimensional echocardiography. Left ventricular volumes were calculated from 15 hearts at 25 volumes ranging from 50 to 280 ml by the following methods: 1) biplane cineventriculography using the area-length method; 2) two-dimensional echocardiography by the apical biplane method using a summation of discs algorithm in 15 cases and the single-plane, four-chamber method using a summation of discs algorithm in 10 cases; and 3) three-dimensional echocardiography using a polyhedral surface reconstruction volume computation algorithm based on multiple nonparallel, nonevenly spaced short-axis cross sections. RESULTS: Results were compared with true volume, and a nonparametric analysis of variance was performed. Both measurement bias (systematic error) and imprecision (random error) were assessed. All methods tended to underestimate the true volume (two-dimensional echocardiography -6.1 +/- 17.6%, three-dimensional echocardiography -4.7 +/- 5.0% and biplane cineventriculography -3.9 +/- 8.2%), although differences were not significant. Although there was a significant correlation between the magnitude of measurement bias and the size of the volume being measured for two-dimensional echocardiography and cineventriculography, the bias of three-dimensional echocardiography was fairly constant over the range of volumes. When bias was accounted for, two-dimensional echocardiography was significantly less precise than cineventriculography and three-dimensional echocardiography in terms of percent error (15.3 +/- 11.9%, 5.6 +/- 5.7% and 3.9 +/- 3.4%, respectively). CONCLUSIONS: Three-dimensional echocardiography using a polyhedral surface reconstruction algorithm for volume computation provides accuracy comparable to that of biplane cineventriculography in this in vitro model. Standard two-dimensional echocardiographic volume computation is significantly less accurate than the other two methods.


Assuntos
Algoritmos , Cineangiografia/métodos , Ecocardiografia/métodos , Processamento de Imagem Assistida por Computador/métodos , Volume Sistólico , Função Ventricular Esquerda , Análise de Variância , Animais , Viés , Estudos de Avaliação como Assunto , Modelos Lineares , Matemática , Modelos Cardiovasculares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Suínos
20.
J Am Soc Echocardiogr ; 6(5): 467-75, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8260164

RESUMO

Two-dimensional (2D) echocardiographic methods for quantitative left ventricular volume computation have been shown to have a low predictive accuracy and reproducibility. To address the problem of geometric assumptions and image plane positioning errors inherent in 2D echocardiography, three-dimensional (3D) echocardiographic systems have been constructed that provide spatial registration and display of transducer-image position and orientation. Although 3D echocardiography has been shown to accurately measure volume in vitro and in vivo, only preliminary data exist demonstrating its superiority over standard 2D echocardiography. We calculated the volume of 30 water-filled latex balloon phantoms of varying size (40 to 200 ml) and shape using each method. Fifteen phantoms were nondistorted (ellipsoid or pear shaped); 15 were symmetrically distorted (dumbbell shaped). Although both 2D and 3D echocardiography showed an excellent correlation to the true volume (r = 0.97 and 0.99, respectively), the standard error of the estimate for 2D echocardiography was twofold larger than for 3D echocardiography (SEE = 6.7 ml and 3.52 ml, respectively). The true volume was slightly underestimated by 3D echocardiography (-2.83 ml), whereas 2D echocardiography overestimated a similar amount (+2.87 ml). The accuracy and variability for 2D echocardiography were significantly poorer (5.22% +/- 5.66% and 5.29% +/- 5.6%, p = 0.001 and 0.002, respectively) as compared with 3D echocardiography (3.7% +/- 2.65% and 2.65% +/- 1.9%, respectively). We conclude that 3D echocardiography with guided image plane positioning and a novel algorithm for volume computation (polyhedral surface reconstruction) achieves significantly more accurate and reproducible results than conventional 2D echocardiography with the modified Simpson's rule.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ecocardiografia/métodos , Volume Cardíaco , Ventrículos do Coração , Humanos , Técnicas In Vitro , Modelos Estruturais , Reprodutibilidade dos Testes
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