bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of the Proximal Orifice Flowfield Under Pulsatile Flow Conditions and Confining Wall Geometry
Authors: ANAYIOTOS ANDREAS S. , FAN POHOEY , PERRY GILBERT J. , MYERS JERRY , ELMAHDI ABDELAZIZ M. , NANDA NAVIN C.
Published: December 2007

Hemodynamic studies of regurgitant lesions in the heart focus on identifying a reliable noninvasive method of volumetric flow calculation. In these studies the influence of blood viscosity to the flowfield under pulsatile flow conditions and constraining wall geometry has not been examined in detail. Pulsatile flow studies in straight tubes have shown that viscous effects significantly influence the periodic flowfield, especially near the wall. The purpose of this study is to investigate the significance of transient effects in the flowfield proximal to a lesion under constraining wall geometry. The proximal flowfield was analyzed with computational fluid dynamics (CFD) computer simulations and color flow Doppler mapping (CFM). Three different stroke volumes and regurgitant waveforms were investigated for upstream wall orientations that varied from ‐ 64° to + 64° (measured from the orifice plane). Results showed that for each upstream wall orientation, a single instantaneously normalized centerline velocity distribution characterized the flowfield throughout the cycle. The centerline distributions were in phase with the pressure gradient and almost identical to the corresponding steady‐state distributions. Minor deviations were observed near the wall, where viscous effects were predominant. Transient flow effects such as blunt profiles and pressure velocity phase shifts, which were observed in straight circular tubes, were not observed in regurgitant orifice flowfields. This is true even under severe confinement conditions.
Assessment of Left Atrial Appendage Structure and Function by Transesophageal Echocardiography
Authors: YAO SIU‐SUN , MEISNER JAY S. , FACTOR STEPHEN M. , FRANK CHARLES W. , STROM JOEL A. , SHIRANI JAMSHID
Published: December 2007

This article examines the transesophageal echocardiographic assessment of the left atrial appendage anatomy and function in individuals without significant structural heart disease and in those with atrial fibrillation with or without cardioembolism or mitral valve stenosis. We also summarize the available data in the usefulness of transesophageal echocardiographic studies in patients undergoing cardioversion for atrial fibrillation and percutaneous balloon valvuloplasty for mitral stenosis. Also, potential limitations and ongoing developments in the use of transesophageal echocardiography in the assessment of the left atrial appendage are outlined, and recommendations are given for the uniform reporting of quantitative data.
Transesophageal Echocardiographic Identification of Neck Veins
Authors: La MOTTE LANCE C. , NANDA NAVIN C. , THAKUR ABHASH C. , AGRAWAL GOPAL , KOLDA MICHAL
Published: December 2007

We describe the technique for identification of innominate veins, azygos vein, and left subclavian and internal jugular veins during transesophageal echocardiography. Validation was provided with contrast echocardiography.
The Sensitivity of Exercise Echocardiography Can Be Improved by Taking the Delayed Myocardial Contraction into Account
Authors: LUOTOLAHTI MATTI , SARASTE MARKKU , VOIPIO‐PULKKI LIISA‐MARIA , HARTIALA JAAKKO
Published: December 2007

The purpose of this study was to test whether the systolic myocardial wall motion abnormalities at the early stages of ischemia are applicable to the diagnosis of coronary artery disease. Forty‐four patients with suspected coronary artery disease were studied with the use of low‐level exercise echocardiography. Exercise was stopped at the onset of first cardiac symptoms, and no patient exceeded 70% of the age‐predicted maximal heart rate level. Forty patients had significant stenosis in at least one coronary artery on coronary angiography. Ten control subjects with a low probability of ischemic heart disease also were studied with exercise echocardiography. The first ischemic wall motion abnormality in systole, defined as delayed onset of the contraction (a regional delay of at least 100 milliseconds in a frame‐by‐frame analysis of echocardiograms) without any reduction in systolic movement, was regarded separately from hypokinesis (systolic wall motion excursion of less than 5 mm). When the delayed onset of the contraction also was taken into account, 37 of the 40 patients with coronary artery disease had an ischemic response after exercise. The sensitivity of the test thus was 93%. The reduction in systolic wall movement was detected in only 18 of these patients at the exercise level attained (70% or less of age‐predicted maximal heart rate). There were two false‐positive echocardiograms, but when the control group also was considered, the specificity of the test remained high at 86%. The sensitivity of exercise echocardiography can be increased by paying attention to the delayed onset of the systolic contraction, which occurs at the early stages of ischemia.
Initial Experience with an Internally Rotating Transthoracic Three‐Dimensional Echocardiographic Probe and Image Acquisition on a Conventional Echocardiogram Machine
Authors: PAPAVASSILIOU DIMITRIOS , DOELLING NANCY R. , BOWMAN MICHAEL K. , YEUNG HUBERT , ROCK JOSEPH , KLAS BERTHOLD , CHUNG KEVIN , FYFE DEREK A.
Published: December 2007

Three‐dimensional echocardiography has required motorized external scanning devices that move a standard echo transducer to obtain data sets before reconstruction. These transducer holders are susceptible to axis alignment errors and transducer movement. The use of a three‐dimensional workstation makes acquisition cumbersome. An internally rotating 5‐MHz “omniplane” transthoracic transducer, specifically designed for three‐dimensional echocardiography, and an integrated three‐dimensional acquisition software package that allows single machine acquisitions were validated in 50 pediatric patients. Children were 1 day to 16 years old and had 22 different cardiac pathological conditions imaged. Ninety‐eight of the 104 (94%) data sets collected were successfully reconstructed in three dimensions. Acquisitions took 3–6 minutes depending on the increment of internal rotation. Minimum total study time to set up and complete the acquisition was 12 minutes. The new probe and software makes three‐dimensional acquisitions and reconstructions of consistently high quality, rapid, reliable, and user friendly.
Transthoracic Echocardiographic Visualization of Calcification of the Sinotubular Ridge of the Ascending Aorta
Authors: D'CRUZ IVAN A. , CALDERON ERICK , CLARK REGENIA
Published: December 2007

Calcification of the ridge between the sinus of Valsalva and the tubular segments of the ascending aorta has been documented at autopsy, but no echocardiographic description has yet been published. We describe the two‐dimensional echocardiographic appearances in 33 men (mean age, 69 years). Sinotubular ridge calcification manifested as a dense small echo projecting into the aortic lumen, precisely at the junction of the sinus of Valsalva and tubular aortic segments. Calcification in the aortic valve cusps, mitral annulus, basal mitral leaflets, and papillary muscles also were frequently present. This previously unknown entity must be distinguished from atheromatous aortic plaques.
Influence of Cardiac Pacing Mode on Left Atrial Appendage Flow Velocity
Authors: YOSHITOMI HIROYUKI , TANABE KAZUAKI , ASANUMA TOSHIHIKO , SHIMIZU HIROMI , KOBAYASHI KANAKO , ONO MIWA , MURAKAMI YO , SANO KAZUYA , ISHIBASHI YUTAKA , SHIMADA TOSHIO
Published: December 2007

Previous studies have shown that the incidence of thromboembolism is higher in patients with single‐chamber ventricular demand (VVI) pacemakers than in patients with dual‐chamber (DDD) pacemakers. However, data on left atrial appendage flow velocity in pacing patients are limited. To investigate the influence of the pacing mode on the left atrial appendage flow velocity, we studied 19 patients with permanent DDD pacemakers and measured the left atrial appendage flow velocity by transesophageal echocardiography at baseline (during DDD pacing) and after switching to VVI pacing. The indications for pacemaker implantation were second‐ and third‐degree atrioventricular block (AVB group, n = 11) and sick sinus syndrome (SSS group, n = 8). Compared with the DDD pacing mode, there was a significant decrease in the left atrial appendage flow velocity during VVI pacing in both the SSS group (43 ± 14 vs 23 ± 7 cm / sec, P < 0.05) and the AVB group (59 ± 18 vs 41 ± 18 cm / sec, P < 0.05). In eight patients with persistent retrograde ventriculoatrial conduction during VVI pacing, the left atrial appendage flow velocity was markedly decreased (from 43 ± 16 to 25 ± 9 cm / sec, P < 0.05). In five (63%) of the eight patients, left atrial appendage flow velocity was less than 25 cm/sec. A reduction in left atrial appendage flow velocity when switching from DDD to VVI pacing may account for an increased risk of thrombus formation in the left atrial appendage (an increased thromboembolic risk in patients in sinus rhythm with VVI pacemakers).
Silent Pulmonary Embolism of a Large Right Atrial Thrombus
Authors: TSOUKAS ATHANASIOS , ATHANASOPOULOS GEORGE , KOLIANDRIS IOANNIS , KOUTELOU MARIA , RITSOU MARINA , CHRISTAKOS STAMATIOS , COKKINOS DENNIS V.
Published: December 2007

We report the case of a patient who was admitted to the hospital with acute pulmonary embolism 2 weeks after a complicated pelvis fracture. Echocardiography revealed a large, long, and mobile thrombus in the right atrium. The patient was scheduled to undergo urgent surgical thrombectomy. Preoperative echocardiography did not detect any thrombi in the right heart and pulmonary artery. The obvious embolism of this large thrombus in the pulmonary circulation was silent as the patient remained asymptomatic and hemodynamically stable. We discuss the contribution of echocardiography to the appropriate therapeutic management of right atrial thrombi and particularly to the cancellation of urgent operative thrombectomy.
Intraoperative Transgastric Echo Assessment During Left Ventricular Outflow Tract Surgery
Authors: FROMMELT PETER C. , LEWIS DAVID A. , PELECH ANDREW N.
Published: December 2007

Standard transesophageal echocardiography (TEE) views of the left ventricular outflow tract (LVOT) are limited by poor Doppler beam alignment with the peak velocity of flow. Transgastric imaging allows well‐aligned continuous‐wave Doppler interrogation of the LVOT and was attempted during intraoperative TEE in all children undergoing LVOT surgery at Children's Hospital of Wisconsin. Thirty‐eight patients, ranging in age from 2 days to 18 years (median, 5.2 years) and in weight from 2.9 to 100 kg (median, 16.7 kg), had TEE during surgery to resect membranous or fibromuscular subaortic obstruction (20 patients), valvuloplasty for aortic stenosis/insufficiency (13 patients), aortoplasty for supravalvar stenosis (one patient), or repair/replacement for aortic insufficiency (four patients). In four patients, transgastric images of the LVOT could not be obtained. Intraoperative Doppler gradients identified severe residual obstruction (mean, 67 ± 13.5 mmHg) after surgery in seven patients; six of these patients underwent immediate repeat operation with subsequent adequate relief, and one patient required later aortoventriculoplasty for persistent annular/valvar obstruction. All other patients had successful LVOT reconstruction with intraoperative Doppler gradients ranging from 0 to 46 mmHg, and none required early repeat operation. Good correlation was found between the intraoperative transgastric gradient (mean, 25.8 ± 17.7 mmHg) and the early postoperative transthoracic echo gradient (mean, 21.8 ± 21.4 mmHg). In addition, there was consistent agreement in the assessment of aortic insufficiency between the transesophageal and transthoracic studies. We conclude that transgastric Doppler assessment of the LVOT is a critical component of intraoperative monitoring during LVOT surgery and is a reliable predictor of residual obstruction.
Long‐Term Follow‐Up and Dobutamine Stress Echocardiography of 19‐mm Prosthetic Heart Valves
Authors: HUNZIKER PATRICK R. , SPÖNDLIN BERNHARD , HEDIGER STEPHAN , BURCKHARDT DIETER , BRETT WOLFGANG , BUSER PETER
Published: December 2007

Background: In patients with a small aortic root, the use of 19‐mm valve prostheses for valve replacement is controversial because of the small orifice area of these valves. Methods: To assess stress hemodynamics in patients with 19‐mm valve prostheses, to find predictors of unfavorable hemodynamics, and to document the long‐term follow‐up, we examined 30 patients (age, 64 ± 19 years; 27 women and 3 men; follow‐up, 38 ± 50 months) clinically and with the use of dobutamine stress echocardiography. A history was taken, and a physical examination was performed. At rest and during dobutamine stress, Doppler echocardiography was performed. Results: At rest, transprosthetic gradients were moderately elevated with mean and peak gradients of 15 ± 7 and 32 ± 14 mmHg, and effective orifice areas were small (0.91 ± 0.31 cm2). Gradients rose markedly during stress (mean, 37 ± 14 mmHg; peak, 83 ± 41 mmHg). Predictors of high transprosthetic gradients were larger body surface area, younger age, and valve type. Mean and peak gradients were lower with St. Jude Medical Hemodynamic Plus valves than with standard St. Jude Medical (P < 0.05) and other valves, and the effective orifice area was highest (1.07 ± 0.29 cm2; P < 0.05 versus standard St. Jude Medical) in this valve model. Sixty percent of patients developed significant dynamic subvalvular or intraventricular gradients (84 ± 41 mmHg) during dobutamine stress. Conclusions: After aortic valve replacement with 19‐mm prostheses in patients with a small aortic root, dobutamine stress leads to high transvalvular gradients, which are dependent on valve model, age, and body surface area. In addition, 60% of patients develop significant dynamic outflow obstructions. These findings and the persistence of some degree of exercise‐induced symptoms in 70% of patients suggest that alternative surgical techniques should be considered if the size of the aortic annulus demands a 19‐mm valve, especially if the patient seeks physical activity, is young, or is of larger body size.
Echocardiography of the Inferior Vena Cava, Superior Vena Cava, and Coronary Sinus in Right Heart Failure
Authors: SHALA M. BASHAR A. , D'CRUZ IVAN A. , JOHNS CAMEILA , KAISER JACKIE , CLARK REGENIA
Published: December 2007

Echocardiographic evaluation of the three major systemic venous channels that drain directly into the right atrium has hitherto received less attention than it deserves. Attention had been paid initially to inferior vena cava dilatation and lack of collapsibility (plethora) as signs of systemic venous congestion. Superior vena cava imaging has not been part of routine echographic evaluation; however, our recent observations on superior vena cava appearance by the right supraclavicular approach provide evidence that dilatation of superior vena cava correlates with that of inferior vena cava as a marker for venous congestion. The coronary sinus caliber, which has been virtually ignored, may also provide echographic signs of systemic congestion, namely, dilatation and lack of normal narrowing during atrial contraction.
Myocardial Velocity Gradient Assessed by a Tissue Doppler Imaging Technique
Authors: UEMATSU MASAAKI , MIYATAKE KUNIO
Published: December 2007

Although tissue Doppler imaging (TDI) is a promising technique for quantitative regional left ventricular wall motion analysis, Doppler angle of incidence and translational motion of the heart influence the velocity measurement by TDI because, in principle, TDI detects the velocity against the transducer. Myocardial velocity gradient (MVG) is derived from TDI as the slope of the regression line for a transmural velocity profile across the myocardial wall, which reflects regional wall thickening and thinning dynamics. Thus, regional diastolic and systolic function may be quantified by using MVG. MVG is also validated to be independent of the translational motion both theoretically and clinically. MVG may therefore be used as an indicator of regional wall motion even under such a condition that the translational motion of the heart cannot be neglected. Our preliminary experience suggests that the quantitative and objective nature of MVG enhances the diagnostic power of stress echocardiography. Further development of the automated, real time processing system and the algorithm for the apical approaches should be awaited for the practical approaches of MVG to be applied to daily clinical practice.
Changing Patterns of Transesophageal Echocardiography Use in the Intensive Care Unit
Authors: HARRIS KEVIN M. , PETROVIC OLIVERA , DÁVILA‐ROMÁN VICTOR G. , YUSEN ROGER D. , LITTENBERG BENJAMIN , BARZILAI BENICO
Published: December 2007

Since its advent, the use of transesophageal echocardiography (TEE) has grown rapidly. In patients undergoing TEE in the intensive care unit over two time periods (4 years apart), we evaluated whether TEE led to new/unsuspected findings or changes in patient management. Results showed that the indications for which patients underwent TEE changed considerably between the two time periods. Hemodynamic instability was an indication for TEE in 41% of the patients in the first interval and 56% of the patients in the second interval. TEE frequently established a new diagnosis (41%) and led to significant management changes (28%) in both time periods. These changes occurred despite the use of a pulmonary artery catheter in nearly 2/3 of the patients studied. Therefore, despite increasing and changing use, TEE frequently establishes unsuspected diagnosis and directly influences patient management when used in intensive care patients.
Transesophageal Echocardiographic Diagnosis of Coronary Stenosis in a Stroke Patient
Authors: NANDA NAVIN C. , GOMEZ CAMILO , LIU MING , TERRY JOHN B. , TULYAPRONCHOTE ROEKCHAI , SAMAL ADITYA K. , THAKUR ABHASH C. , KUMAR NARAYAN VIRENJAN , YU LEE TAO , OCAK OZLEM , JINDAL AJAY
Published: December 2007

This study represents another example of the usefulness of transesophageal echocardiography in the assessment of stenosis involving the proximal, mid, and distal coronary arteries in stroke patients referred for exclusion of a cardiac source of embolism.
The Role of Transesophageal Echocardiography During Port‐Access Minimally Invasive Cardiac Surgery
Authors: APPLEBAUM ROBERT M. , COLVIN STEPHEN B. , GALLOWAY AUBREY C. , RIBAKOVE GREG H. , GROSSI EUGENE A. , TUNICK PAUL A. , KRONZON ITZHAK
Published: December 2007

The recent development of endovascular catheters that are placed via the femoral artery and vein has enabled patients to be placed on cardiopulmonary bypass without the need for direct visualization of the heart or great vessels via sternotomy. This has allowed cardiac surgery to be performed through smaller, thoracotomy incisions. Placement of these catheters initially was performed under fluoroscopic guidance, which has major imaging limitations. Now, transesophageal echocardiography (TEE) has replaced fluoroscopy as the primary imaging technique to assist in the placement of endovascular catheters during minimally invasive, port‐access cardiac surgery. In our institution, 449 port‐access procedures have been performed from May 1996 through July 1998. We found that TEE is able to adequately visualize the cardiac structures and assist in the placement of the endovascular catheters in all patients. Fluoroscopy is helpful only as an aid to the use of TEE for placement of the coronary sinus catheter.
Transcatheter, Endovascular Repair of Abdominal Aortic Aneurysm: Feasibility, Noninvasive Diagnosis, Problems, and Follow‐Up
Authors: KRONZON ITZHAK , VARKEY MATHEW , TUNICK PAUL A. , RILES THOMAS , ROSEN ROBERT
Published: December 2007

Until recently, the repair of an abdominal aortic aneurysm (AAA) required major surgery. Recently, the transcatheter technique has allowed minimally invasive endovascular stenting of infrarenal AAAs. This procedure is less traumatic and is associated with a shorter hospital stay than conservative surgery. With the stent placement, the effective aortic lumen diameter decreases and the aneurysmal space is excluded from the circulation. Ultrasonographic studies have allowed imaging of the abdominal aorta, its main branches, and the endovascular stent. The aortic blood flow after the repair is ideally limited to the stent lumen. Follow‐up studies have permitted reevaluation of the aorta and the stent, with special emphasis on the aortic expansion and blood flow within the excluded space. These studies have correlated well with other imaging techniques such as intravascular ultrasound, computed tomography scanning, and aortography.
Echocardiographic Evaluation of Patients with Primary Pulmonary Hypertension Before and After Atrial Septostomy
Authors: ESPINOLA‐ZAVALETA NILDA , VARGAS‐BARRÓN JESUS , ISAAC TAZAR JORGE , MIGUEL CASANOVA JOSÉ , KEIRNS CANDACE , ROMERO CÁRDENAS ANGEL , GASPAR JORGE , SANDOVAL JULIO
Published: December 2007

Objectives: To characterize the early changes in right ventricular [right ventricle (RV)] geometry and function, as assessed by two‐dimensional (2‐D) and Doppler echocardiography, after balloon‐dilation atrial septostomy (BDAS) in patients with severe primary pulmonary hypertension (PPH). Background. Survival in PPH is to a great extent dependent on the functional status of the RV. BDAS recently has been shown to improve functional class and hemodynamics in patients with PPH nonresponsive to conventional vasodilator treatment. Methods: Ten patients with severe PPH who underwent BDAS were studied with transthoracic and transesophageal 2‐D and Doppler echocardiography. RV dimensions were measured in the apical four‐chamber view. Continuous‐wave Doppler echocardiography was used to obtain peak velocity of tricuspid regurgitation. Transesophageal echocardiography (TEE) primarily was used for the follow‐up of the atrial septal defects (ASDs). Results: In the early post‐BDAS studies, right atrial and ventricular dimensions significantly decreased in all patients (P < 0.05). Global right ventricular wall motion (RVWM) also improved. RV percent change in area after septostomy inversely correlated with the changes in RV systolic area (r =–0.75; P < 0.05) and also with the baseline (preprocedure) values of RV percent change in area (r =–0.77; P < 0.05). Neither RV wall thickness nor the degree of tricuspid regurgitation were modified significantly after the procedure. Conclusions: BDAS in the setting of severe PPH results in moderate and salutary changes in geometry and function of the RV as assessed by 2‐D echocardiography. These changes mainly appear to be the result of the decompression effect of atrial septostomy.
Fistulous Connection of a Greatly Dilated Tortuous Right Coronary Artery to the Coronary Sinus
Authors: KOUVOUSIS NICOLAOS , FOUKARAKIS MANOLIS , LAZAROS GEORGE , MATSAKAS EVANGELOS , DEFTEREOS SPIROS , LAKOUMENTAS JOHN , ZACHAROULIS APOSTOLOS
Published: December 2007

Congenital coronary artery fistulas (CAFs) constitute an unusual cardiovascular anomaly. The aneurysmal appearance of CAFs is not uncommon and depends on the shunt size. However, few cases of ectatic coronary arteries (type III according to Markis et al. classification‐diffuse ectasia in one vessel) supplying the fistulas have been reported. Below, we report the case of a 65‐year‐old woman, who referred to our department because of worsening exertional dyspnea. Echocardiographic evaluation, both transthoracic and transesophageal, performed after admission disclosed a giant tortuous ectatic right coronary artery with a fistulous connection to the coronary sinus. The presence of the CAF was confirmed by cardiac catheterization. In addition, we discuss the pathophysiology of the above congenital anomaly, as well as its management.
Stress Echocardiography in Aortic Stenosis
Authors: BERMEJO JAVIER , GARCÍA‐FERNÁNDEZ MIGUEL A. , CARLOS ANTORANZ J. , MAR MORENO M. , LUIS DELCAN JUAN
Published: December 2007

Stress interventions have been classically combined with cardiac catheterization recordings to understand the hemodynamic principles of valvular stenosis. Indices of aortic stenosis such as pressure gradient and valve area were based on simple hydraulic principles and have proved to be clinically useful for patient management during a number of decades. With the advent of Doppler echocardiography, these hemodynamic indices can be readily obtained noninvasively. Abundant evidence obtained using exercise and pharmacological stress echocardiography has demonstrated that the assumptions of classic hemodynamic models of aortic stenosis were wrong. Consequently, it is recognized that conventional indices may be misleading indicators of aortic stenosis significance in particular clinical situations. To improve diagnostic accuracy, several alternative hemodynamic models have been developed in the past‐few years, including valve resistance and left ventricular stroke work loss, among others. Nevertheless, these more‐accurate indices should be obtainable noninvasively and need to demonstrate greater diagnostic and prognostic power than conventional indices; preliminary data suggest such superiority. Stress echocardiography is well established as the tool of choice for testing hypothesis and physical models of cardiac valve function. Although the final role of alternative indices is not yet well established, the new insights into valvular hemodynamics provided by this technique may change the clinical assessment of aortic stenosis.
Three‐Dimensional Echocardiographic Evaluation of Aortic and Mitral Valve Stenosis
Authors: MOHR‐KAHALY SUSANNE , MENZEL THOMAS , KUPFERWASSER IRI , SCHLOSSER ALEXANDER , VON BARDELEBEN STEPHAN
Published: December 2007

Dynamic volume rendered three‐dimensional echocardiography allows the spatial recognition of anatomy and function of the aortic and mitral valves with acceptable image quality. The aortic valve can be best visualized in a view from the ascending aorta down to the valve level, thus allowing an overview of the aortic aspect of the valve in a surgeon's perspective in ∼ 80% of patients. Planimetric measurement of the aortic valve area was possible in 88% of patients, and there is no systematic overestimation or underestimation of aortic valve area compared with two‐dimensional echocardiography and catheterization. The entire valvular circumference of the mitral valve can be assessed from both a left atrial and a left ventricular perspective. Advantages of the three‐dimensional transesophageal echocardiography mitral valve area determination compared with transthoracic two‐dimensional planimetry and Doppler‐derived pressure half‐time method are present in patients with severely calcified mitral valves and in those with combined aortic regurgitation.
Myocardial Hematoma Documented by Transthoracic Echocardiography After Sequential Coronary Artery Stenting
Authors: BANERJEE DEEPAK , VENEZIA MICHELE , LÓPEZ‐CANDALES ANGEL
Published: December 2007

We report the case of a patient who deteriorated suddenly while undergoing endoluminal coronary artery reconstruction with multiple stents to the left anterior descending coronary artery. With the aid of transthoracic echocardiography, a pericardial effusion was noted; however, dissection of the ventricular wall due to a large myocardial hematoma was also identified. Emergency exploration with evacuation of the pericardial blood with coronary artery bypass graft surgery was successfully accomplished. We discuss the possible factors that could have been associated with this unforeseen complication and the potential benefit of transthoracic echocardiography in early recognition.
Contrast‐Enhanced Doppler Ultrasound of Renal Artery Stenosis
Authors: LENCIONI RICCARDO , PINTO STEFANIA , CIONI DANIA , BARTOLOZZI CARLO
Published: December 2007

Over the past few years, there has been extensive research for a reliable, noninvasive, and nonionizing imaging method to screen for renal artery stenosis (RAS). Doppler ultrasound (US) is one of many modalities that have been evaluated for the detection of RAS. The lack of standardization in examination protocols and diagnostic criteria, as well as the wide differences in reported accuracy among different laboratories, however, have prevented universal acceptance of this technique as a reliable screening test for RAS. Recently, the introduction of US contrast agents has substantially expanded the potentials of color Doppler US. The use of microbubble echo enhancers in combination with harmonic Doppler imaging has been shown to improve diagnostic confidence by improving the operator's ability to visualize the renal arteries, and to significantly reduce the number of equivocal examinations. In addition, contrast‐enhanced harmonic Doppler US can currently provide objective functional assessment of RAS through analysis of time‐intensity renal enhancement curve. State‐of‐the‐art contrast‐enhanced Doppler US seems to have the potential to become a useful screening test for patients at risk from renovascular hypertension and a tool for follow‐up of patients who undergo revascularization procedures.
Online Quantification of Left Ventricular Function: Correlation with Various Imaging Modalities
Authors: PÉREZ JULIO E.
Published: December 2007

The need for more objectively quantifiable evaluation of the left ventricular function, obtainable on line with echocardiography, was fulfilled through modifications of integrated backscatter imaging to permit real‐time differentiation of the endocardium and the blood pool area in every image frame. Operator‐guided study of individual cardiac chambers permitted instantaneous measurement of chamber areas in either the systole or diastole, with resulting physiologically meaningful recordings that relate to cardiac function. Validation studies by various approaches suggest that the methodology is clinically relevant, and further improvements in design will sharpen its applicability in the future.
Online Quantification of Cardiovascular Function in Children
Authors: KIMBALL THOMAS R.
Published: December 2007

Echocardiography is the most valuable diagnostic tool in evaluating congenital anatomic pathology. Improvements in transducer resolution and development of color Doppler echocardiography have resulted in the ability to delineate cardiac anatomy in detail. Online quantification of cardiovascular function represents a similar advance in terms of evaluating physiology. Performing an online quantification examination requires attention to technical factors such as avoiding chamber foreshortening, optimizing endocardial tracking, ensuring patient cooperation, and accounting for the effects of respiration. A typical examination consists of performing acoustic quantification on the left ventricle in both short‐axis and apical four‐chamber views and on the left atrium from the apical four‐chamber view. From these views, ventricular systolic and diastolic function, as well as atrial systolic function, can be assessed. As in adult patients, acoustic quantification indices in children correlate well with similar indices measured off line. Acoustic quantification data in children show that, unlike adults, the left ventricular filling is almost exclusively dependent on passive filling, with minimal atrial contribution. Acoustic quantification indices have also been useful in monitoring left ventricular function in intensive care and emergency department settings to evaluate the acute effects of a clinical manipulation. Acoustic quantification can also be used to assess the function of ventricles of unusual geometry such as in hypoplastic left and right heart, double‐inlet single ventricle, and unbalanced atrial ventricular septal defect. In these types of ventricles, systolic and diastolic systemic ventricular function has been shown to be markedly altered compared with a normal left ventricle. Acoustic quantification can also be used to assess diastolic function in a variety of pediatric diseases, such as transplant rejection and insulin‐dependent diabetes mellitus. In summary, online quantification of cardiovascular function represents a significant advance in the ability to understand cardiovascular physiology in children.
Acoustic Quantification Today and Its Future Horizons
Authors: MOR‐AVI VICTOR , SPENCER KIRK T. , LANG ROBERTO M.
Published: December 2007

We briefly review previously published work based on the uses of acoustic quantification (AQ) or validation of this technology. We also discuss the limitations of AQ in a critical review of the literature, including operator dependency, signal noise, and low temporal resolution. We describe some enhancements made to AQ software to address these limitations and improve the accuracy of this technique, including digital beam processing, harmonic imaging, and signal averaging. Several anticipated applications are also briefly described for those interested in the future development of this technology. These future applications include noninvasive long‐term monitoring of ventricular function and objective assessment of regional ventricular wall motion in two and three dimensions.
Clinical Use of Ischemic Markers and Echocardiography in the Emergency Department
Authors: MUTTREJA MANOJ R. , MOHLER EMILE R.
Published: December 2007

We searched the medical literature for articles containing markers of cardiac ischemia and echocardiography in the evaluation of patients presenting to the emergency department to determine their combined clinical use. Several published articles indicate two‐dimensional echocardiography is a useful and cost‐effective imaging technique for the evaluation of patients with chest pain in the emergency department. New studies are emerging that evaluate ischemic markers in combination with echocardiography to assess patients presenting to the emergency department with chest pain. We searched the MEDLINE Database for English‐language articles published from December 1980 to August 1998 using the key words troponin, echocardiography, myocardial infarction, and emergency. These key words were crossed referenced to determine publications in this area. Pertinent trials and reviews were selected from the database. There were six articles evaluating biochemical markers of ischemia and echocardiography to assess patients presenting with acute coronary syndromes in the emergency department. Very few studies combined the information obtained from novel ischemic markers and echocardiogram analysis to help delineate potential cardiac etiologies of acute coronary syndromes. However, the limited studies available indicate that echocardiography is both sensitive and specific for detecting acute myocardial infarction. The presence of regional wall motion abnormalities increases the chance of in‐hospital complications and likelihood of developing congestive heart failure after admission for unstable angina. The combined use of troponin T levels and echocardiographic imaging was a more powerful predictor of adverse events than were isolated results. Myocardial scarring with ventricular wall thinning or aneurysm may allow for rapid diagnosis of‘occult’coronary artery disease in a patient presenting with chest pain who does not have a previous history of a cardiovascular event. Echocardiography may also help identify other cardiovascular causes of chest pain, such as aortic dissection, aortic stenosis, cardiac tamponade, pericarditis, and hypertrophic cardiomyopathy. The clinical use of combining ischemic markers of disease with echocardiographic imaging seems justified given their unique clinical advantages. Future clinical trials are needed to determine whether the combination of novel ischemic markers and echocardiography can provide for a more expedient and accurate diagnosis, resulting in improved patient care and a safe reduction in unnecessary hospitalization.
Role of Echocardiography in the Emergency Department for Identifying Patients with Myocardial Infarction and Ischemia
Authors: KONTOS MICHAEL C.
Published: December 2007

Echocardiography is a valuable, noninvasive diagnostic tool that can provide information on systolic function and valvular abnormalities and can provide alternative explanations for causes of chest pain. Experimental as well as clinical studies have shown that wall motion abnormalities have a high sensitivity for predicting myocardial infarction. More recent studies, performed in the emergency department on patients evaluated for myocardial ischemia, have reported similar results. An important aspect is that necrosis is not necessary to cause wall motion abnormalities; therefore, echocardiography can also be used to identify patients with ischemia without infarction. Importantly, sensitivity is significantly higher than that for electrocardiography and is comparable to that for myocardial perfusion imaging. Newer developments, such as digital transmission over telephone lines, may lead to more widespread routine use in the emergency department. Acute emergency department echocardiography appears to be a promising tool when used in the evaluation of patients with chest pain.
Pericardial Effusion as a Consequence of Acute Myocardial Infarction
Authors: GREGOR PAVEL , WIDIMSKÝ PETR
Published: December 2007

Pericarditis is a common complication of acute myocardial infarction (MI). Its incidence during the first few days after acute MI is 24%–43% when echocardiographic criteria are used, whereas the frequency of clinical pericarditis is much less (from 5% for all acute MIs to 21% for anterior Q wave MIs). Clinical, electrocardiographic findings are discussed. Effusions are mostly small, and the resolution is frequently slow, lasting 1–18 months. Tamponade is extremely rare in the absence of cardiac rupture. Q wave MIs (especially anterior) are more frequently accompanied by pericardial effusion. The prognostic significance of echocardiographically proved pericarditis is questionable.
Rapid Three‐Dimensional Myocardial Contrast Echocardiography: Volumetric Quantitation of Nonperfused Myocardium After Intravenous Contrast Administration
Authors: BAE RICHARD Y. , BELOHLAVEK MAREK , TANABE KAZUAKI , GREENLEAF JAMES F. , SEWARD JAMES B.
Published: December 2007

Current acquisition methods for quantitative three‐dimensional myocardial contrast echocardiography require long acquisition times and therefore require the invasive administration of deposit contrast agents administered intra‐arterially or into the left atrium. This study addressed the feasibility of obtaining accurate and precise quantitative volumetric measurements of nonperfused myocardium after an intravenous bolus of echocardiographic contrast agent using a rapid three‐dimensional myocardial contrast echocardiographic acquisition technique. An open‐chest pig model of acute left anterior descending coronary artery (LAD) occlusion was used. After LAD ligature, an intravenous bolus of contrast agent was given and images were obtained over a 12‐second period using a continuously rotating transducer placed at the apical position. There was no significant microbubble destruction during the rotational acquisition period as measured by differences in mean gray scale values of apical, mid, and basal myocardial regions between the first and last image frames of acquisition. Calculated volumes of nonperfused myocardium demonstrated significant agreement and correlation (mean difference ± SD =–0.30 ± 1.71 cm3; r = 0.89; P < 0.01; y = 1.06x – 1.08) with anatomic specimens. When expressed as percent of total LV volume being nonperfused, the mean difference ± SD was 2.1 ± 3.6%, r = 0.94, P < 0.01, and y = 1.33x – 4.08. We conclude that accurate and precise measurements of nonperfused myocardium after an acute LAD coronary artery occlusion can be obtained after the intravenous bolus administration of a contrast material when a rapid 12‐second acquisition with a continuously rotating transducer is used.
An Unusual Case of Embolic Stroke: A Permanent Ventricular Pacemaker Lead Entirely Within the Arterial System Documented by Transthoracic and Transesophageal Echocardiography
Authors: ASLAM AHMAD ADNAN , McILWAIN ELIZABETH F. , TALANO JAMES V. , FERGUSON T. BRUCE , McKINNIE JAMES , KERUT EDMUND KENNETH
Published: December 2007

A pacemaker lead in the left ventricle is a rare complication of implantation. Recognition of this complication is important because thromboembolic events are associated. We report the first case, to our knowledge, of a patient who had a permanent pacemaker implanted via the left subclavian artery to the left ventricle, which is documented by electrocardiography, chest radiography, thoracic echocardiography, and transesophageal echocardiography.
Role of Dobutamine Stress Echocardiography for Preoperative Cardiac Risk Assessment Before Major Vascular Surgery: A Diagnostic Tool Comes of Age
Authors: POLDERMANS DON , BAX JEROEN J. , THOMSON IAN R. , BOERSMA ERIC , MEER PETER VAN DER , FIORETTI PAOLO M. , ELHENDY ABDOU , VEN LOUIS M.M. VAN DE , ROELANDT JOS R.T.C. , URK HERO VAN
Published: December 2007

Background: Cardiac complications are a major cause for perioperative mortality and morbidity Also, the presence and severity of underlying coronary artery disease (CAD) determine long‐ten prognosis after successful surgery. Aim: This overview evaluates the additional value ofdobutamir, stress echocardiography (DSE) to common clinical cardiac risk factors and other noninvasii cardiac imaging modalities for perioperative and late cardiac prognosis. Results: DSE provides tl attending physician with preoperative prognostic information for perioperative and long‐ten prognosis for cardiac events. It also enables the selection of high risk patients for evaluation i cardiac risk reduction therapies. Conclusions: DSE is a useful tool for preoperative cardiac ris evaluation in addition to common clinical cardiac risk factors. (ECHOCARDIOGRAPHY, Vo ume 17, January 2000)
Diagnostic Catheterization and Balloon Sizing of Atrial Septal Defects by Echocardiography Guidance Without Fluoroscopy
Authors: EWERT PETER , BERGER FELIX , DAEHNERT INGO , KRINGS GREGOR , DITTRICH SVEN , LANGE PETER. E
Published: December 2007

To avoid x‐ray exposure prior to interventional closure of atrial septal defects (ASDs), we recently developed a technique for diagnostic catheterization and balloon sizing of the defect by echocardiography guidance without fluoroscopy. We report on our first experiences with this technique. Fourteen patients with atrial septal perforations (mean age, 23 years; range, 1–66 years) underwent diagnostic catheterization and balloon sizing prior to possible interventional defect closure. Mean size of the defects was 16 mm (7–29 mm). Mean left‐to‐right shunt was Qp/Qs =2.0 (range, 1.0–4.0). Without fluoroscopy, the procedures were performed in two children by transthoracic echocardiography (TTE) and in 12 patients by both TTE and transesophageal echocardiography (TEE). Mean procedure time was 59 minutes (range, 35–90 minutes). We conclude that oxymetry, pressure recordings, and the estimation of the balloon‐stretched size of atrial septal perforations can be performed safely by echocardiographic guidance without fluoroscopy. The x‐ray exposure for patient selection prior to a transcatheter closure of an ASD can be avoided with this technique.
Cardiogenic Shock Secondary to Myocardial Rupture Contained by a Thrombus with Left Atrial and Pulmonary Venous Compression
Authors: SHARMA NAGARAJA D. , FARHA AMJAD , ALAM MOHSIN
Published: December 2007

myocardial rupture, transesophageal echocardiography, intrinsic left atrial compression, intrinsic pulmonary vein compression, acute myocardial infarction
Does the Lack of Hyperkinesis During Dobutamine Stress Echocardiography Predict the Functional Significance of Coronary Arterial Stenosis?
Authors: YAMASHITA KAZUHITO , TAKEUCHI MASAAKI , TSUDA YUKI , SONODA SHINJOU , MIURA YASUSHI , ISHINO YOUICHIROU , NAKASHIMA YASUHIDE
Published: December 2007

The clinical implication of the lack of hyperkinesis during dobutamine stress echocardiography (DSE) has not been determined. We hypothesized that a lack of hyperkinesis during graded doses of dobutamine infusion would reflect the severity of coronary flow abnormality distal to the stenosis and provide the functional significance of coronary arterial stenosis. The aim of the present study was to investigate the prevalence of the lack of hyperkinesis inpatients with normal coronary arteries and to determine its value in patients with single‐vessel disease. A total of 63 consecutive patients who subsequently revealed angiographically normal coronary arteries underwent DSE. Thirty‐one consecutive patients with angina and single‐vessel disease also underwent both DSE and exercise thallium single‐photon emission computed tomography (SPECT). According to the response of wall motion during low and peak doses of dobutamine infusion, patients were divided into three groups (group A, hyperkinesis was present during both low dose and peak stress; group B, hyperkinesis was present only during low dose; group C, no hyperkinesis). SPECT images were divided into 16 segments, and thallium uptake at each segment was scored from 0 (normal) to 3 (severe defect). Thallium uptake score index (TSI) was calculated as total thallium score divided by 16 at stress and delayed image. The prevalence of group A, B and C was 56 (89%), 3 (5%), and 4 (6%) inpatients with normal coronary arteries. The corresponding values were 11 (35%), 8 (26%), and 12 (39%) in patients with single‐vessel disease (P < 0.0001). In patients with single‐vessel disease, there was no significant difference in percent diameter stenosis (group A, 59%± 8%; group B, 69%± 16%; group C, 67%± 13%) and the prevalence of proximal stenosis (45%, 25%, and 42%) among three groups. However, TSI at stress image was significantly lower in group A (0.21 ±0.14) than in group B (0.45 ± 0.20, P < 0.05) and group C (0.53 ± 0.27, P < 0.01). TSI at delayed image was also significantly lower in group A (0.07 ±0.11) than in group C (0.18 ± 0.15, P < 0.05). Because the lack of hyperkinesis during DSE was observed in 11% of patients with normal coronary arteries, it does not always predict the presence of significant coronary artery stenosis. However, this finding related to the severity of perfusion abnormality by exercise thallium SPECT in patients with single‐vessel disease. These results suggest that the lack of hyperkinesis during dobutamine infusion would predict functional significance of coronary arterial stenosis and provide myocardial perfusion status distal to the stenosis in patients with single‐vessel disease.
Delayed Left Atrial Wall Dissection After Mitral Valve Replacement
Authors: IDIR MESSAOUD , DEVTLLE CLAUDE , ROUDAUT RAYMOND
Published: December 2007

We report two unusual cases of left atrial wall dissection creating a left atrial pseudoaneurysm associated with regurgitation a few months after mitral valve replacement. We emphasize the important role of transesophageal echocardiography in the diagnosis. The two patients successfully underwent surgery.
Large Right Atrial Thrombus with Pulmonary Embolism
Authors: HUNG MING‐JUI , WANG CHAO‐HUNG , KUO LI‐TANG , CHERNG WEN‐JIN
Published: December 2007

We present the cases of two patients, aged 67 and 77 years, who were admitted for the evaluation of rapidly progressive dyspnea and syncope, respectively. Both patients developed large right atrial thrombi with pulmonary embolism. The first patient received recombinant tissue plasminogen activator and survived with an uneventful result, whereas the second patient received operative thrombectomy followed by intravenous heparin and died 15 days later of pulmonary infarction with pulseless electrical activity. Data from these limited experiences suggest that thrombolytic therapy might be considered in patients withright heart thrombi with pulmonary embolism.