bluuebunny/crossref_metadata_2025 huggingface dataset:
Diagnostic Performance of Two‐Dimensional Versus Three‐Dimensional Transesophageal Echocardiography Images of Selected Pathologies Evaluated by Receiver Operating Characteristic Analysis
Authors: BELOHLAVEK MAREK , FOLEY DAVID A. , SEWARD JAMES B. , GREENLEAF JAMES F.
Published: August 2007

The sensitivity and specificity of 2‐D and 3‐D echocardiographic images for the detection of selected morphological abnormalities were compared using receiver operating characteristic (ROC) analysis. Five experienced clinical echocardiographers blinded to the patients' diagnoses evaluated the 20 original static 2‐D image sets and 20 corresponding 3‐D reconstructions using a five point categorical scale that ranged from definitely abnormal to definitely normal. The ROC curve for the 3‐D images was significantly (P lt; 0.05) closer to the ideal discrimination function than was the ROC curve for the 2‐D transesophageal images (i.e., the sensitivity of the 3‐D images was higher than that of the 2‐D sequential images at the same specificity). In conclusion: 3‐D transesophageal images provided better visual clues for the identification of morphological abnormalities than did serial 2‐D echocardiographic images despite the same input information in both image formats. The use of ROC analysis assisted in the comparison of these two imaging techniques.
Color Doppler of Diastolic Flow Converging Into Coronary Ostia by Transthoracic Ultrasound
Authors: GIESLER MARTIN , STAUCH MARTIN , HOMBACH VINZENZ
Published: August 2007

The flow convergence method is a recently described color Doppler method for determination of flow rate across orifices in patients with valve leaks and ventricular septal defects. For a given geometry, the flow net of the flow convergence region is predictable, which allows one to derive flow rate from the local velocity at given points within the field of convective acceleration proximal to the orifice. This underlying fluid dynamic principle should also apply to coronary ostia. Therefore, we looked to see if the flow convergence region proximal to the coronary ostia can be imaged by color Doppler. In 16 healthy adults we imaged the aortic root by transthoracic color Doppler echocardiography in the parasternal short axis. A low velocity setup was used (PRF 450–2000 Hz, wall filter 50–200 Hz). Eighty‐four percent of the coronary ostia was seen (left 15/16; right 12/16). A color signal of the coronary flow convergence region was displayed in 88% of coronary ostia (left 15/16; right 13/16). By quantitative analysis of these color maps the velocity profile across the flow convergence was determined. This always resulted in a steady increase in velocity when approaching the ostium. Within 2 to 18 mm proximal to the orifice, the absolute velocities ranged from 1.2 to 16 cm I sec. The coronary flow convergence region can be imaged by color Doppler. However, the potential estimation of instantaneous diastolic coronary flow rate from these images needs further evaluation.
Three‐Layer Appearance of the Arterial Wall in Intravascular Ultrasound Imaging:
Authors: FINET G. , MAURINCOMME E. , DOUEK Ph. , TABIB A. , AMIEL M. , BEAUNE J.
Published: August 2007

A three‐layer appearance of the arterial wall in intravascular ultrasound imaging has been described, but its correspondence with a characteristic histologic structure is still controversial. Some studies emphasize the imprecision of vessel‐wall measurements carried out on the intravascular ultrasound image, while other studies cast doubt upon the reality of the three‐layer appearance and its correspondence with a characteristic histologic structure. The consequences of this disputed point are important with respect to the interpretation of such images. We performed an in vitro study using phantoms and heighty postnecroptic arteries to determine the relations existing between histology, acoustic properties of arterial wall tissue, and intravascular ultrasound image formation. Measurements carried out on phantoms showed a significant overestimation of wall thickness, equal to axial resolution and due to the radial impulse response of the imaging system. Measurements performed on normal arterial walls of muscular arteries with a three‐layer appearance or normal arterial walls of elastic arteries with a single‐layer appearance showed very clearly that there was no correlation with histologic measurements of the thickness of intima and media taken individually. However, measurements (n = 53), which include the intima plus the media, exhibit excellent correlation with histologic measurements: r = 0.95 ± 0.03, y = 1.02 + 11.2. The shiny internal ring of the muscular artery wall on the image corresponded always to the internal elastic lamina (IEL). Thus, the three‐layer appearance is not an artifact. However, specific alterations, which this appearance may undergo during image formation such as beam incidence angle, lateral and radial impulse responses, and the effects of proximity of the transducer to the arterial wall, modified the shape and sizes characterizing the IEL on intravascular ultrasound images. The description and understanding of such image alterations are necessary for both interpreting them and determining which are the only reliable measurements that can be performed.
Quantification of Images Obtained During Myocardial Contrast Echocardiography
Authors: JAYAWEERA ANANDA R. , SKLENAR JIRI , KAUL SANJIV
Published: August 2007

This article describes currently used quantitative methods for analysis of data obtained during myocardial contrast echocardiography. The specific issues addressed are: obtaining time‐intensity curves from the myocardium in order to derive transit rates of microbubbles through the myocardium; defining spatial distribution of flow within a myocardial segment; and color‐coding algorithms used to define the extent and magnitude of hypoperfusion within a cross‐section of the heart. These methods are being adopted by several companies dealing with acquisition and analysis of echocardiographic data and should become available soon for clinical use.
Three‐Dimensional Echocardiography for Quantitative Left Ventricular Wall Motion Analysis:
Authors: MÆHLE JØRGEN , BJOERNSTAD KNUT , AAKHUS SVEND , TORP HANS G. , ANGELSEN BJØRN A.J.
Published: August 2007

A method for quantitative LV wall motion analysis based on 3‐D reconstruction of the LV endocardial surface is presented. The reconstruction is based on a minimum of three transthoracic apical 2‐D cineloops of the LV, digitally transferred from the ultrasound scanner to a computer. Images are obtained by rotating the transducer around the LV long axis. Endocardial borders are traced with an automatic edge detection algorithm with manual correction. These borders are used with a specially designed computer algorithm for reconstruction of LV cavity 3‐D shape, and LV volumes, ejection fraction, and endocardial surface area can be determined. The end‐diastolic and end‐systolic endocardial surfaces are compared for analysis of regional wall motion. A threshold value is selected to discriminate between normal and abnormal wall motion. Regional wall motion abnormalities are displayed in a bull's eye plot, and the corresponding endocardial surface area is expressed in percent of the total endocardial area. Phase analysis is performed from reconstruction of the endocardial surface throughout the cardiac cycle, and displays regions with abnormal wall motion as being out of phase with LV volume variation. Thus, LV 3‐D reconstruction performed by this method can be used for quantitative analysis of wall motion in several clinical situations, and due to the simplicity of processing the data, can be useful outside the research laboratory.
Effect of a Stabilized Microbubble Echo Contrast Agent on Hemolysis of Human Erythrocytes Exposed to High Intensity Pulsed Ultrasound
Authors: BRAYMAN A.A. , AZADNIV M. , MAKIN I.R.S. , MILLER M. W. , CARSTENSEN E. L. , CHILD S. Z. , RAEMAN C. H. , MELTZER R. S. , EVERBACH E. C.
Published: August 2007

Microbubble contrast agents have been shown to enhance ultrasonic cell lysis in vitro when exposed to continuous‐wave ultrasound having spatial peak temporal average (SPTA) intensities of a few W/cm2. The response is strongly dependent upon the hematocrit (HCT) of the cell sample; detectable cell lysis essentially disappears as the HCT approaches 5%‐10%. This study was conducted to determine whether high intensity pulsedsound is an effective lytic agent in the presence of preexisting potential cavitation nuclei (Albunex® contrast agent). Human erythrocytes weresuspended in autologous plasma to HCTs ranging from 1%–40%. Suspensions were exposed or sham exposed for 60 seconds to focused, pulsed ultrasound. The pulse duration was 1 msec, and the pulse repetition frequency was 20 Hz. The pressure amplitudes, spatial peak pulse average (SPPA) intensity, and SPTA intensity were 4.7 MPa peak positive pressure, ‐2.7 MPa peak negative pressure, 420 W/cm2, and 8.5 /cm2, respectively. Samples were exposed to ultrasound in a dialysis membrane exposure vessel rotating at 200 rpm. When included in the erythrocyte samples, the Albunex concentration was 35 μL/mL suspension. Significant ultrasound‐induced hemolysis in the absence of Albunex was observed only at the lowest HCT value tested (1%). In the presence of Albunex significant cell lysis was observed at all tested HCT values. The relative fraction of cells lysed by the combination of ultrasound exposure and Albunex diminished with increasing HCT, but the number of cells lysed per sample was nearly constant over the range of 5%–40% HCT. The ultrasound exposure parameters used in this study differ substantially from those associated with diagnostic imaging equipment; it is not valid to infer from the present results that the use of Albunex in diagnostic applications will induce or enhance hemolysis in vivo.
Echocardiography in Patients With Constrictive Pericarditis Before and After Pericardiectomy
Authors: TOKGÖZOǦLU S. LALE , KES SIRRI , ORAM AYSEL , DEMIRCIN METIN , PAŚOǦGLU İLHAN , UǦRLU ŞEVKET
Published: August 2007

Fifteen patients with constrictive pericarditis were prospectively evaluated with echocardiography and Doppler recordings during respiratory monitoring. Eleven who agreed to surgery also underwent right heart catheterization and a repeat echocardiography with Doppler 10 days after pericardiectomy. Preoperatively, there was a significant inspiratory decrease in the mitral E wave (P < 0.05) and increase in the tricuspid E wave velocities (P < 0.05), which both normalized after pericardiectomy. The mitral deceleration times increased from 110 ± 40 to 149 ± 46 msec (P < 0.05) postoperatively. The preoperative hepatic vein velocities showed an accentuated systolic flow pattern. The systolic to diastolic ratio of the hepatic vein velocities was higher in patients who improved with surgery (1.42 ± 0.31 vs 0.65 ± 0.13) (P < 0.05). Postoperatively the diastolic flow became more pronounced. There was a 100% expiratory diastolic flow reversal in eight patients preoperatively, which normalized after pericardiectomy. Clinically these patients improved significantly postoperatively. Left atrial size, ejection fraction, and mitral and tricuspid filling velocities during respiratory monitoring could not predict surgical outcome. Pericardiectomy improved Doppler filling dynamics in all patients although this was not parallel to clinical improvement.
Evaluation of Left Ventricular Mechanical Efficiency in the Human Heart by Echocardiography
Authors: LIU XING , WANG JIN RUI , LI JI RU
Published: August 2007

It has been proved that ventricular systolic wall stress and myocardial mass are two major determinants of myocardial oxygen consumption (MVO2) in the intact human heart. The product of stress and mass, which we named the stress‐mass‐index (SMI), has the correct unit for work (cm X dyns/cm = dyns x cm), and is very similar to the pressure‐volume work of the heart. To examine whether SMI might be used as a predictor of MVO2, left ventricular mean systolic wall stress (Mσc,Mσm), left ventricular wall mass (Mm), and stroke work (SW) were measured by echocardiography in normal and diseased human hearts. The area bounded by the end‐diastolic and end‐systolic pressure‐volume lines, and the systolic segment of the pressure‐volume loop (PVA) were also measured in each subject. It has been proved repeatedly in the past that PVA correlates significantly with MVO2. Our results showed that there was a close correlation between PVA and SMI in every group (r − 0.76‐0.91, P < 0.001 all), which proved indirectly that SMI may reflect MVO2. On this basis, left ventricular efficiency (Eff) was estimated as SW/SMI × 100%. Effin 30 patients with essential hypertension (17.1%± 1.6%) was normal compared to the control subjects (19.9%± 2.4%). However, Eff of 22 hypertensive patients with mild left ventricular dysfunction (13.3%± 2.1%), 33 coronary artery heart disease patients (10.8%± 1.8%), and 11 chronic congestive heart failure patients (6.6%± 2.1%) was significantly decreased compared to the control. These changes in Eff were in agreement with clinical findings and left ventricular ejection fractions (EF). For the first time, we have measured Eff noninvasively; the results are very close to those evaluated invasively in human hearts by others. This reflects the fact that it is possible to calculate Eff noninvasively. We conclude that the product of left ventricular systolic wall stress could reflect the change in MVO2 at rest. SW/SMI may be a useful method in evaluating Eff and ventricular function.
Transesophageal Echocardiographic Diagnosis of a Congenital Circumflex Coronary Artery to Coronary Sinus Fistula in an Adult
Authors: MORENO JUAN B. GONZÁLEZ , BELTRAN ALVARO , PIZZANO NELSON
Published: August 2007

We report a congenital circumflex coronary artery to coronary sinus arteriovenous fistula diagnosed by transesophageal echocardiography in a 38‐year‐old asymptomatic male. The coronary arteriovenous fistula was suggested by two‐dimensional transthoracic color Doppler. A first nondiagnostic angiography was performed, and it was during the second one, that the fistula could finally be visualized after a special dye technique was used. The high fistula flow rate prevented us from seeing it with regular dye concentration. Transesophageal echocardiography was precise in the anatomical and hemodynamic evaluation and it was essential in guiding the angiographic examination and surgical repair.
Acoustic Quantification of Left Ventricular Volumes and Function in Children With Congenital and Acquired Heart Disease
Authors: HIJAZI ZIYAD M. , CAO QI‐LING , GEGGEL ROBERT , SCHWARTZ STEVEN L. , MARX GERALD R. , RHODES JONATHAN , FULTON DAVID R. , PANDIAN NATESA
Published: August 2007

Automated acoustic quantification (AQ) technique for left ventricular (LV) volume and function has been validated in vitro and in adults. Its reliability and applicability in children has not been validated. Therefore, 30 children with different forms of congenital and acquired heart disease underwent cineangiography followed by AQ for LV volumes and ejection fraction measurements. Their median age was 3.6 years and median weight was 14 kg. In all patients, AQ was obtained without difficulty; the quality was adequate in all but the largest patient. The mean LV end‐diastolic volume by cineangiography was 66 mL compared with 47 mL by AQ; there was good correlation between the two techniques with an r = 0.92, P < 0.001. The mean LV end‐systolic volume was 24 mL by cineangiography compared to 19 mL by AQ, with good correlation, r = 0.94, P < 0.001. The median ejection fraction by cineangiography was 63% compared to 63.5% by AQ. However, the correlation was not strong, r = 0.52, most likely due to lack of wide range of ejection fractions. In conclusion, AQ yielded quantitative measurements of size and function in normal and abnormal shaped ventricles as reliable as cineangiography and could be used to follow LV quantitatively in patients in whom accurate assessment is essential.
Multiplane Transesophageal Echocardiographic Detection of Sinus Venosus Atrial Septal Defect
Authors: MAXTED WILLIAM , FINCH ANA , NANDA NAVIN C. , KIM KEE SIK , SANYAL RAJATSUBHRA
Published: August 2007

We present two case reports of diagnosis and evaluation of sinus venosus atrial septal defects by multiplane transesophageal echocardiography.
On Echocardiography and Medical Economics
Authors: GAL RAMI A.
Published: August 2007

Echocardiography has established itself as an important tool for imaging the heart and great vessels. Its advantages include portability, a variety of optional approaches and views, interpretation of images in real time, no exposure to radiation, and virtually no complications‐all at a cost significantly lower than that of comparable imaging methods. Research in the field continues to flourish and diversify to new frontiers (e.g., intracoronary ultrsound, three‐dimensional imaging, etc.). It is easy to see why physicians increasingly rely on echocardiography for diagnosis, management, prediction of outcome, and, in some cases, screening for cardiovascular disease.
Cost‐Effectiveness of Echocardiography for Evaluation of Children with Murmurs
Authors: DANFORD DAVID A.
Published: August 2007

Echocardiography is widely accepted as an accurate diagnostic test to evaluate heart murmurs in children, however its costs, and the ubiquity of murmurs in children, discourage its universal application. The purpose of this article is to identify some clinical circumstances in which the cost of echocardiography is justified for the evaluation of heart murmurs in infants and children. Eight common clinical problems were selected in which a heart murmur is present and a diagnosis is called for. Effectiveness of echocardiography and less costly clinical diagnostic methods in these settings were compared. In some circumstances, echocardiography is worth the cost, because clinical evaluation is unacceptably insensitive to important disease (the premature infant with a murmur which might represent a patent ductus arteriosus, the infant with a dysmorphic syndrome and a murmur). In others, the expert clinical examination is highly accurate (the asymptomatic child with a heart murmur) and is preferred over the echocardiogram as the initial diagnostic approach on the grounds of cost. When the expert clinical examination suggests minor structural heart disease, a continuum of echocardiographic cost‐effectiveness relative to the expert clinical examination exists between these extremes depending on the working diagnosis. A threshold has not yet been defined at any point on this continuum above which the public will demand the greater diagnostic detail available echocardiographically, and below which the public will refuse to accept its greater cost. Quantitative formal cost‐effectiveness analysis of echocardiography for evaluation of heart murmur in infants and children is not yet feasible because the benefits of echocardiography are indirect, dependent upon the as yet unmeasured benefits of correct management of congenital heart defects. To go beyond simple comparison of efficacy of echocardiography with less costly methods, further work is required in outcomes research in congenital heart disease.
Fee‐For‐Service Versus Capitation‐Based Reimbursement
Authors: GAL RAMI A. , VOLKERT PAUL , MALIK IJAZ , SCHMIDT DONALD H. , KUBOTA JAMES , SARNOSKI JOSEPH
Published: August 2007

Historically, health insurance carriers (HIC) have reimbursed physicians on a fee‐for‐service basis for echocardiographic studies. With the emergence of managed care, the HIC now may have the option of paying on a capitation basis. To determine whether the method of reimbursement had any bearing on the types of patients referred for echocardiographic services, we conducted a two‐phase (retrospective) study. In Phase One, we assessed two groups of ambulatory patients with regard to patient characteristics, medical reason for referral, and echocardiographic results. Group A (4,066 patients) had insurance plans that stipulated reimbursement for echocardiographic services as part of capitation for cardiology services. Group B (3,061 patients) had plans that reimbursed for echocardiographic services on a fee‐for‐service basis. In Phase Two, we assessed a total of 5,947 patients (3,833 from Group A and 2,114 from Group B) over a period of 40 months to determine the frequency of referral for a second echocardiogram within 2 years of a normal one and the repeat normalcy rate. The results showed that the capitation reimbursement group included younger, predominately female patients who were referred more often for a more benign reason and who more frequently were diagnosed echocardiographically with less severe disease, higher rates of normalcy, and repeat normalcy. These findings suggest that in our geographic area the capitation method of reimbursement permitted more liberal utilization of echocardiographic services. In this era of cost awareness, the study suggests the need for better screening of patients referred for echocardiographic services.
Correlation of Echocardiographic Fractional Area Change with Radionuclide Left Ventricular Ejection Fraction
Authors: DOMANSKI MICHAEL J. , COLLERAN JOHN A. , CUNNION ROBERT E. , NANDA NAVIN C.
Published: August 2007

Fractional area change of the left ventricle during systole, measured in the parasternal short‐axis view, is an easily calculated index of systolic function. We assessed the correlation of echocardio‐graphic left ventricular fractional area change with radionuclide ventriculography derived left ventricular ejection fraction. Forty patients who had both echocardiography and radionuclide ventriculography were studied. Nonuniformity of left ventricular function was present in 38%. For the group as a whole the correlation coefficient for fractional area change and ejection fraction was 0.82 (P < 0.001). For patients with uniform systolic function the correlation coefficient was 0.79 (P < 0.001). For those with regional differences, the correlation coefficient was 0.72 (P < 0.005). We conclude that echocardiographically derived fractional area change, measured in the parasternal short‐axis view, is an excellent measure of left ventricular function even in patients with heterogeneity of regional function.
Transesophageal Echocardiographic Diagnosis of Periaortic Abscess Extending into Interatrial Septum
Authors: ESPINOLA‐ZAVALETA NILDA , VARGAS‐BARRON JESUS , ROMERO‐CARDENAS ANGEL , RIJLAARSDAM MARIA , DIAZ‐MONCADA SAMUEL , KEIRNS CANDACE
Published: August 2007

A case of native aortic valve endocarditis is presented in which a vegetation originated a supra‐annular abscess with extension into the inferior portion of the atrial septum. This was diagnosed in vivo by transesophageal echocardiography and confirmed at surgery.
Noninvasive Visualization of an Apparent Patent Intracoronary Stent by Transesophageal Echocardiography
Authors: NIXDORFF UWE , ERBEL RAIMUND , RUPPRECHT HANS‐JÜRGEN , KEARNEY PETER , TRAUTMANN STEFFEN , MEYER JÜRGEN
Published: August 2007

In the area of increasing interventional techniques there is a need for noninvasive imaging modalities to provide postinterventional follow‐up. We were able to visualize the apparent patency and measure the dimensions of an intracoronary Palmaz‐Schatz stent in the left circumflex coronary artery using transesophageal two‐dimensional echocardiography. This report indicates the potential of echocardiography to directly assess coronary stents.
Transesophageal Echocardiographic Findings of a Dehisced Duran Mitral Annuloplasty Ring
Authors: OSMAN KHIDIR , WILLMAN BERT , NANDA NAVIN C. , KIM KEE‐SIK , PACIFICO ALBERT D.
Published: August 2007

We describe multiplane transesophageal echocardiographic findings in a patient with severe mitral regurgitation secondary to dehiscence of a Duran ring.
Echocardiographic Appearances of Direct Drainage of Hepatic Vein into Right Atrium in Adults
Authors: D'CRUZ IVAN A. , SMITH KENNETH A.
Published: August 2007

Anomalous hepatic venous drainage directly into the right atrium is known to occur in infants or children with atrial isomerism, abdominal heterotaxy, and absence of the inferior vena cava (IVC), but we could find no previous reports of partial anomalous hepatic venous drainage in adults, in the echocardiographic literature. We describe two adults in whom the two‐dimensional and color flow Doppler findings indicated drainage of a hepatic vein directly into the right atrium. I n both, a normal IVC entered the right atrium at its normal location, and a unique abnormal tongue like structure—an “extra Eustachian valve”—was attached to the right atrial wall near the entry of the anomalous directly draining hepatic vein. We speculate that the hepatic venous anomaly and the “extra Eustachian valve” both result from aberrant development of the embryonic sinus venosus.
Transesophageal Echocardiographic Diagnosis of Aortic Graft Dehiscense at Coronary Anastomoses and Pseudonaneurysm Rupture into Right Atrium
Authors: ROYCHOUDHURY DEBASISH , NANDA NAVIN C. , KIM KEE SIK , ZORN GEORGE L. , KOPPANG JOYCE
Published: August 2007

We describe a case of aortic graft dehiscence at coronary anastomoses with rupture into the right atrium of the pseudoaneurysm complicating aortic graft replacement. These were diagnosed by intraoperative transesophageal echocardiography.
Transesophageal Echocardiographic Findings of a Patient with Hypertrophic Cardiomyopathy, Mitral Valve Prolapse, and Coronary Artery Disease
Authors: BARÓN ALBERTO , ROYCHOUDHURY DEBASISH , KIM KEE‐SIK , NANDA NAVIN C.
Published: August 2007

The coexistence of hypertrophic cardiomyopathy and mitral valve prolapse has been previously described, but it is not a common finding. We describe the transesophageal echocardiographic findings of a patient with hypertrophic obstructive cardiomyopathy, mitral valve prolapse, and coronary artery disease.
The Assessment of Left Ventricular Filling Dynamics Using an Online Automatic Border Detection Algorithm
Authors: SAPIN PETER M. , KWAN OI LING , XIE GONG‐YUAN , SMITH MIKEL D. , DEMARIA ANTHONY N.
Published: August 2007

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.
False Aneurysm of the Aortic Root and Right Ventricular Outflow Obstruction
Authors: FALCON‐EICHER SYLVIE , EICHER JEAN‐CHRISTOPHE. , MORVAN YANN , TATOU ETIENNE , CHAVANET PASCAL , DAVID MICHEL , BRUNOTTE FRANCOIS , WOLF JEAN‐ERIC
Published: August 2007

Aortic root abscess often complicates the course of aortic valve endocarditis. In severe cases, left ventricular‐aortic discontinuity may occur, providing challenging technical problems for the surgeon. Moreover, surgical intervention sometimes takes place in a semi‐emergency context, and the patches and prosthesis are sutured into friable tissues and subjected to high systemic pressures. Subsequently, paravalvular leaks and prosthesis dehiscence are not uncommon; postoperative false aneurysm of the aortic root is a much more unusual complication. We report one case of right ventricular outflow obstruction that occurred after surgical treatment of an aortic root abscess. Echocardiographic data were useful, but magnetic resonance imaging provided valuable information about the anatomic extent of the cavity.
Magnetic Resonance Imaging of the Thoracic Aorta
Authors: ROFSKY NEIL M.
Published: August 2007

Magnetic resonance imaging (MRI) is well‐suited for imaging the vascular system and is of particular value in assessing the anatomy and pathologies of the thoracic aorta. The intrinsic contrast between the blood pool and the vascular structures allows excellent depiction of intra‐ and extravascular anatomy and eliminates the need for intravenous contrast agents. A large field of view provides a complete evaluation of the mediastinum and chest. Both qualitative and quantitative techniques are available, which can yield physiological data in addition to anatomical information. The multiplanar capability offers images in any plane, allowing an accurate assessment of the longitudinal extent of disease and providing images perpendicular to vessels, even when tortuous. MRI currently represents an essential component of the imaging strategies available to assess the thoracic aorta and may come to function as a gold standard for certain conditions. As the technology continues its rapid evolution, MRI will most likely be able to serve as an effective noninvasive evaluation to provide all of the anatomical, pathological, and physiological information required of a comprehensive examination of the thoracic aorta.
Significance of “Strands” on Mitral Mechanical Prostheses During Late Follow‐Up After Surgery
Authors: ROBERT FRÉDÉRIC , ROUDAUT RAYMOND , PEPIN CHRISTOPHE , GARRIGUE STÉPHANE , LABBE THIERRY , BONNET JACQUES
Published: August 2007

The presence of “strands” on mitral mechanical prostheses (MMP) has been described, although their significance has yet to be established. The aim of this study was to determine the incidence and clinical implications of “strands” on MMP in late follow‐up by a retrospective analysis of 320 consecutive patients who had undergone a transesophageal echocardiographic (TEE) examination under standardized conditions 7 ± 6 years after mitral surgery. Twenty patients (6.25%) with “strands,” defined as highly mobile linear echogenic densities, were identified. This group was compared with a control group of 38 patients, matched for age, sex, and interval between surgery and TEE study, selected at random from this population. Patients with MMP dysfunction were excluded. Type of prosthesis, echographic characteristics (left atrial diameter, spontaneous echo contrast, ejection fraction), and anticoagulant status were not found to bear any relationship to the presence of strands. However, the prevalence of previous embolic events was significantly higher in the “strand” group (10/20 [50%]) than in the control group (7/38 [18.4%]) (P > 0.05). The “strand” group also contained more patients with a prior history of mitral prosthesis thrombosis (7/20 [35%] vs 1/30 [2.6%]; P > 0.05). However, long‐term follow‐up (1‐4 years) was uneventful. These results suggest that: (1) in late follow‐up, strands are rare in patients with MMP (6%); and (2) strands were related to previous thromboembolic episodes.
Echocardiographic Features of Ventricular Septal Rupture with Right Ventricular Aneurysm After Acute Myocardial Infarction
Authors: PARRO ADELINO , da SILVEIRA LUIS CARLOS , FRANCISCHETTI ALOÍSIO , de ALMEIDA GOMES DOMINGOS ANTONIO , ANTÔNIO GUBOLINO LUÍS , VITO ARDITO ROBERTO , CARLOS NICOLAU JOSÉ
Published: August 2007

Postinfarction ventricular septal defect is a life‐threatening disorder that may be adequately treated if the diagnosis is obtained promptly. Two‐dimensional color Doppler echocardiography is a reliable tool for this diagnosis and gives additional information regarding its location, size, and shape. The authors emphasize the feasibility of this method to depict a particular form of postinfarction interventricular septal rupture, which developed an aneurysm inside the right ventricular cavity. Its characteristics were completely defined by color Doppler echocardiography and confirmed at surgery.
Aortic Stenosis or Atresia with Associated Hypoplasia of the Left Ventricle
Authors: RYCHIK JACK
Published: August 2007

Aortic atresia or stenosis, when associated with hypoplasia of the left ventricle, presents the cardiac surgeon with a challenging reconstruction. Many preoperative and intraoperative decisions are now made on the basis of ultrasound data. Furthermore, echocardiography provides the most convenient way to time the stages of the reconstructive sequence and assess the hemodynamic result.
Impact of Beta Blockers on Dobutamine‐Atropine Stress Echocardiography
Authors: ROMÁN José Alberto San , VILACOSTA ISIDRE , ROLLÁN MARÍA JESÚS , CASTILLO JUAN ANTONIO , SÁNCHEZ‐HARGUINDEY LUIS , AVILÉS FRANCISCO FERNÁNDEZ
Published: August 2007

Dobutamine increases oxygen demand in the myocardium and is used in conjunction with echocardiography to detect coronary artery disease. Beta blockers (BB) are partial antagonists of dobutamine and, therefore, offset dobutamine effects. Still, the impact of BB therapy on dobutamine stress echocardiography is not clear. One hundred forty‐one dobutamine‐atropine echocardiographic studies have retrospectively been analyzed: 27 patients were on BB (19%; group I); and 114 off BB (81%; group II). Coronary angiography was performed in a similar percentage of patients (97% and 85%, respectively; P = NS). No differences in clinical and angiographic profile were found between the groups. Sensitivity (83% vs 71%; P = NS) and specificity (100% vs 95%; P = NS) for coronary artery disease were similar in both groups. Atropine was infused more frequently to patients from group I (67% vs 46%; P = 0.04). Limiting side effects and prolonged ischemia presented with the same frequency in both groups. When the dobutamine test was positive, severe extent of ischemia appeared more often in patients from group I than in patients from group II (66% vs 33%; P = 0.03). The majority of patients from group I (55%) with severe extent of ischemia and only 12% from group II received atropine (P = 0.02). No differences were found in dobutamine time and extent of ischemia in patients from group I who had a positive response to dobutamine. On the contrary, patients from group II with one vessel disease had a dobutamine time longer (10.5 ± 3.8 vs 7.8 ± 3.7 min; P < 0.05) and extent of ischemia smaller (1.8 ± 0.4 vs 2.6 ± 0.5 segments; P < 0.05) than patients from group II with multivessel disease. We conclude that: 1) sensitivity of dobutamine‐atropine echocardiography for diagnosis of coronary artery disease remains even if patients are on BB; 2) patients with significant coronary artery disease who are taking BB often develop severe myocardial ischemia during dobutamine‐atropine stress echocardiography; and 3) BB therapy precludes stratification of a positive echocardiographic response. These conclusions should be confirmed in a prospective study to be considered as definitive.
Myocardial Stunning and Unique ECG Changes Associated with Dobutamine Stress Echocardiography
Authors: VILACOSTA ISIDRE , ROMÁN José Alberto San , CASTILLO JUAN ANTONIO , ROLLÁN MARÍA JESU , PERAL VICENTE
Published: August 2007

The clinical, electrocardiographic, and echocardiographic changes associated with myocardial stunning during dobutamine stress echocardiography in a patient with severe left main coronary artery disease are presented.
Antibiotic Prophylaxis for Endocarditis Prevention During Transesophageal Echocardiography
Authors: EICHELBERGER JAMES P.
Published: August 2007

A survey was conducted in order to gain a better understanding of actual practice policies followed by academically affiliated institutions regarding the use of prophylactic antibiotics during transesophageal echocardiography. Results revealed that 10 of the 20 centers routinely used intravenous antibiotic prophylaxis for high risk transesophageal echocardiography. However, 5 of the 20 centers did not use any prophylactic antibiotics routinely, and the remaining 5 centers used primarily oral prophylactic regimens. In addition, the type of patient that was considered high risk for which antibiotic prophylaxis was used differed among institutions. Practice guidelines in 4 of the 20 institutions have changed in the last 5 years. These findings demonstrate a wide variation in the actual practice policies of different institutions, probably reflecting, in part, the lack of convincing evidence that prophylactic antibiotics benefit this subgroup of patients.
Validation of Automated Border Detection in Intravascular Ultrasound Images
Authors: HAUSMANN DIRK , FRIEDRICH GUY , SONI BOBBY , DANIEL WERNER G. , FITZGERALD PETER J. , YOCK PAUL G.
Published: August 2007

Intravascular ultrasound (IVUS) imaging provides cross‐sectional views of the vessel lumen; however, lumen measurements still rely on operator‐dependent border delineation and time‐consuming lumen tracings. We tested a new system for automated lumen border detection in IVUS images based on acoustic quantification of blood and vessel wall. In 10 rabbits, 29 segments of the aorta were imaged in vivo using a 2.9‐Fr IVUS catheter. IVUS images were obtained during motorized pullbacks of aortic segments of 18 mm length. Automated measurements of lumen dimensions were compared to automated measurements of a second pullback through the same segment, lumen measurements derived from visual border tracings in IVUS images, and to quantitative angiography. The automated system showed good reproducibility: Correlations for repeated measurements of lumen area, maximal and minimal lumen diameters were r = 0.97, r = 0.91, and r = 0.93, respectively. Automated measurements also correlated well to visual image analysis (lumen area, r = 0.97; maximal lumen diameter, r = 0.89; minimal lumen diameter, r = 0.89) and to angiographic measurements (lumen area, r = 0.93; lumen diameter, r = 0.95). In 12% of the images, the automated system overestimated lumen dimensions because of weak wall signals in the presence of echolucent structures next to the wall. Signal artifacts from the IVUS catheter itself or strong blood backscatter resulted in lumen underestimation in 6% of the images. Over‐and underestimation of lumen by the border detection system were often associated with eccentric catheter position. Thus, lumen measurements in vivo IVUS images can be performed using an automated border detection system based on acoustic quantification of blood and vessel wall. The system allows reproducible and accurate measurements of lumen area and diameters.
Acquired Intercostal Arteriovenous Fistulas
Authors: SUBAHI SAAD A. , AL‐DAMEGH SALEH , AKHTAR MOHAMMED JAWAID , ARAFAH MOHAMMED R. , MOHAMMED ELGAMRI E.
Published: August 2007

Acquired intercostal arteriovenous fistulas are recognized complications of traumatic injuries. In this article, transesophageal Doppler echocardiographic findings in a patient with posttraumatic acquired intercostal arteriovenous fistulas are presented. The findings have been confirmed by angiography. The demonstration of intercostal arteriovenous fistulas by transesophageal Doppler echocardiography has not been reported before.
Multiplane Transesophageal Echocardiographic Evaluation of Defects of the Atrioventricular Septum
Authors: DHAR PRADIP K. , FYFE DEREK A. , SHARMA SHIVA
Published: August 2007

The availability of multiplane transesophageal probes has dramatically facilitated visualization of complex cardiac anatomy, with full dynamic tracking of anatomic contiguity. This report describes the unique applicability of multiplane transesophageal echocardiography (TEE) for visualization and assessment of a spectrum of congenital cardiac defects involving the cardiac crux, including the atrioventricular septum, inlet muscular septum, and the atrioventricular valves. With further evolution and progressive miniaturization of these probes, the use of this echocardiographic modality will hopefully encroach into the young infant age range, permitting enhanced preoperative and perioperative depiction of complex congenital cardiac anatomy.
Differences in Mexican American and Non‐Hispanic White Veterans' Homocysteine Levels
Authors: Baldwin Carol M. , Bell Iris R. , Giuliano Anna , Mays Mary Z. , Arambula Pete , Alexandrov Andrei
Published: August 2007

Purpose

: To compare homocysteine (Hcy) levels and possible modulatory factors, such as nutrient or supplement intake, between Mexican American and Non‐Hispanic White (NHW) male military veterans scoring at high‐ versus low‐risk for stroke.

Design

: A cross‐sectional survey with a high and low stroke risk biomarkers substudy.

Methods

: Voluntary participants were Mexican American (n=109) and NHW (n=120) veteran outpatients 54 to 85 years of age at a Southwestern Veterans Administration (VA) medical center. Measures included food frequency, health history, and stroke risk scale derived from the Framingham Study. Biomarker subgroups, 30 Mexican American and 30 NHW, half of each group scoring high or low on stroke risk, who were tested for morning fasting blood levels of Hcy, B12, and folate.

Findings

: In the cross‐sectional study (n=229), nutrient intake was comparable between ethnic groups. In the substudy, Mexican Americans (n=30) with high or low stroke risk scores and NHW (n=30) with high stroke risk scores had elevated Hcy levels (12.5; 11.9; 11.4 μmol/L respectively) compared to NHW veterans with low stroke risk scores (7.8 μmol/L) even after controlling for age, education, folate, diabetes, and smoking pack‐years (p=.001). Mexican Americans compared to NHW were significantly more likely to be in the preclinical (17% versus 3% >10 μmol/L) and clinical ranges (69% versus 35% >15 μmol/L) for Hcy.

Conclusions

: Mexican Americans showed higher levels of Hcy whether they scored high or low for stroke, and greater representation in clinical and preclinical Hcy ranges compared to NHW veterans. The Framingham‐derived, predominantly NHW population‐based stroke risk measure might require ethnically relevant stroke risk factors for Mexican Americans.
Orientation Control in Sol–Gel‐Derived BiScO3–PbTiO3 Thin Films
Authors: Wen Hai , Wang Xiaohui , Li Longtu
Published: August 2007

BiScO3–PbTiO3 (BSPT) thin films were fabricated via a sol–gel method on Pt(111)/Ti/SiO2/Si(111) substrates. The effects of different factors on the orientation of the sol–gel‐derived BSPT thin films were investigated. The results showed that a higher lead excess concentration, longer drying time, higher pyrolysis temperature, longer pyrolysis time, higher crystallization temperature, and longer crystallization time could enhance the (100) orientation of the BSPT thin films. Based on the experimental results, a mechanism for the orientation evolution in the sol–gel‐derived BSPT thin films was proposed. The production of the (100) orientation was attributed to the (100)‐oriented PbO nanocrystals forming during the pyrolysis process due to the lattice match.
Dispersion Behavior of ZrB2 Powder in Aqueous Solution
Authors: Lee Sea‐Hoon , Sakka Yoshio , Kagawa Yutaka
Published: August 2007

Dispersion conditions of ZrB2 powder in water were investigated using poly(ethyleneimine) (PEI) as a dispersant. Pulverization of ZrB2 powder to submicrometer size was difficult and a substantial amount of large particles remained after an intensive planatery milling for 72 h. The isoelectric point (IEP) of ZrB2 powder was measured to be pH 5.8 by electrophoresis, which shifted to pH 6.2 after milling. The application of PEI changed the IEP of the boride slurry to ∼pH 11. Well‐dispersed aqueous ZrB2 slurries with a high solid loading (up to 45 vol%) were fabricated at pH 6.5–7.5 by the application of 1.5 wt% PEI.
New Na0.5Bi0.5TiO3–NaTaO3‐Based Perovskite Ceramics
Authors: König Jakob , Jančar Boštjan , Suvorov Danilo
Published: August 2007

X‐ray diffraction analyses and scanning electron microscopy revealed that Na0.5Bi0.5TiO3 (NBT) and NaTaO3 (NTa) form solid solutions across the whole concentration range. With increasing NTa content the symmetry of the solid solutions gradually changed from rhombohedral, on the NBT‐rich side, to orthorhombic, on the NTa‐rich side. No morphotropic phase boundary was found between these phases. With increasing NTa content, the perovskite lattice parameter (ap) and the sintering temperature increase, whereas the grain size decreases. In the case of pure NTa, ceramics with a secondary phase were obtained, identified as Na2Ta8O21, which was formed during the sintering process. A study of the dielectric properties showed that with an increasing concentration of NTa, there was a reduction and broadening of the permittivity maximum, a reduction of the temperatures of the dielectric anomalies, and a reduction of the dielectric losses.
Importance of bicarbonate transport for ischaemia‐induced apoptosis of coronary endothelial cells
Authors: Kumar Sanjeev , Kasseckert Sascha , Kostin Sawa , Abdallah Yaser , Piper Hans Michael , Steinhoff Gustav , Reusch H. Peter , Ladilov Yury
Published: August 2007

Bicarbonate transport (BT) has been previously shown to participate in apoptosis induced by various stress factors. However, the precise role of BT in ischaemia‐induced apoptosis is still unknown. To investigate this subject, rat coronary endothelial cells (EC) were exposed to simulated ischaemia (glucose free anoxia at Ph 6.4) for 2 hrs and cells undergoing apoptosis were visualized by nuclear staining or by determination of cas‐pase‐ 3 activity. To inhibit BT, EC were either treated with the inhibitor of BT 4,4′‐diisothiocyanostilbene‐2,2′‐disulfonic acid (DIDS, 300 μmol/l) or exposed to ischaemia in bicarbonate free, 4‐(2‐hydroxyethyl)‐I‐piperazi‐neethanesulphonic acid (HEPES)‐buffered medium. Simulated ischaemia in bicarbonate‐buffered medium (Bic) increased caspase‐3 activity and the number of apoptotic cell (23.7 + 1.4%versus 5.1 + 1.2% in control). Omission of bicarbonate during ischaemia further significantly increased caspase‐3 activity and the number of apoptotic cells (36.7 1.7%). Similar proapoptotic effect was produced by DIDS treatment during ischaemia in Bic, whereas DIDS had no effect when applied in bicarbonate‐free, HEPES‐buffered medium (Hep). Inhibition of BT was without influence on cytosolic acidification during ischaemia and slightly reduced cytosolic Ca2+ accumulation. Initial characterization of the underlying mechanism leading to apoptosis induced by BT inhibition revealed activation of the mitochondrial pathway of apoptosis, i.e., increase of cytochrome C release, depolarization of mitochondria and translocation of Bax protein to mitochondria. In contrast, no activation of death receptor‐dependent pathway (caspase‐8 cleavage) and endoplasmic reticulum‐ dependent pathway (caspase‐12 cleavage) was detected. In conclusion, BT plays an important role in ischaemia‐induced apoptosis of coronary EC by suppression of mitochondria‐dependent apoptotic pathway.