bluuebunny/crossref_metadata_2025 huggingface dataset:
Late Results with Bioprosthetic Valves in the Elderly
Authors: Helft Gérard , Tabone Xavier , Georges Jean L. , Lomama Eale , Lepailleur Claude , Feuvre Claude Le , Metzger Jean Ph. , Heulin André , Vacheron André
Published: August 2007

Abstract Aim: We report the long‐term outcome of aortic and mitral bioprostheses in patients over 65 years of age at the time of implantation. The aim was to determine actuarial patient survival, causes of death, and the rate of documented primary structural deterioration. Methods: One hundred ten patients 65 years of age (mean, 73.4; range, 65–82) underwent successful bioprosthetic valve replacement (aortic, n = 71; mitral, n = 32; both, n = 7) from 1979 to 1985. The valve was pericardial in 39 cases and porcine in 78. The mean follow‐up was 8.5 years (101.9 months‐total; 934 patient‐years; range, 2 months to 15 years). Results: Actuarial patient survival was 79.6% (71–86) at 5 years and 62.4% (52–71) at 10 years. Forty‐four patients died, 21 from valve‐related causes and 23 from other causes. Thirteen patients (11.8%) had reoperation for valve‐related complications: 10 structural deteriorations, 2 paravalvular leaks, and 1 case of endocarditis. One surgical death occurred (7.7%). Twenty‐six percent of the patients were receiving anticoagulants because of atrial fibrillation, and 6.4% developed severe bleeding (2.9% patient‐years). Conclusions: Long‐term follow‐up of these patients > 65 years of age, undergoing bioprosthetic value replacement surgery revealed a low rate of documented primary structural deterioration (0.95% per patient‐year), a low mortality rate on reoperation (7.7%), and a high mortality rate due to non‐value‐related causes (52.3%). (J Card Surg 1999; 74:252–258)
Mid‐Term Outcome of Surgical Coronary Ostial Plasty: Our Experience
Authors: Bonacchi Massimo , Prifti Edvin , Giunti Gabriele , Leacche Marzia , Ballo Emerico , Furci Barbara , Salica Andrea , Miraldi Fabio , Mazzesi Giuseppe , Toscano Michele
Published: August 2007

Abstract The conventional coronary artery bypass procedure that uses venous or arterial conduit for isolated critical stenosis of the left main coronary artery (LMCA) restores a less physiological perfusion of the myocardium and uses an appreciable length of bypass material, Coronary ostial plasty has been described as an alternative surgical technique in proximal obstructive coronary artery disease without calcifications. Here we report 23 patients (15 males and 8 females aged 37–78 years; mean age 57 years) who underwent surgical ostial plasty. Ostial reconstruction with fresh pericardial patch was performed in all patients: 15 patients with LMCA stenosis, 6 patients with right coronary (RC) ostial stenosis. and 2 patients with both RC artery and LMCA stenosis. In seven cases, coronary artery bypass grafting was added for contralateral distal stenosis with a total of five arterial conduits and six venous grafts. One patient died; the ostial plasty and grafts were patent at necropsy. Thal‐lium‐201 myocardial scintigraphy under stress at 30 days to 6 months after operation demonstrated good myocardial perfusion in 21 of 22 patients. Coronary angiography at follow‐up (49 ± 8 months) demonstrated good surgical ostial plasty results in 21 of 22 patients and good coronary flow in 19 of 22 patients; angiographic study at mid‐term follow‐up revealed only one failure of the surgical ostial plasty technique associated with venous graft obstruction. In 2 other patients CABG failure due to venous graft obstruction (1 patient) or distal stenotic lesions of the left coronary artery (1 patient) was noted. The overall successful outcome of the surgical ostial plasty was 22 of 23. We believe that surgical angioplasty of the coronary ostia may be used in the presence of proximal noncalcified obstructive lesions as an alternative technique, which offers a more physiological revascularization; it also spares grafting material and allows subsequent percutaneous transluminal angioplasty or coronary artery bypass surgery. (J Card Surg 7999; 14:294–300)
Ultrasonic Evaluation of the Carotid Bifurcation
Authors: LANGLOIS YVES E. , ROEDERER GHISLAINE O. , STRANDNESS D. EUGENE
Published: August 2007

Noninvasive tests for the detection of carotid occlusive disease have focused primarily on the indirect assessment of the internal carotid artery by the analysis of arterial pressure and flow. These tests can only detect the presence of flow‐reducing lesions and occlusions; they cannot differentiate between these two entities. Also, the assessment of bilateral disease is difficult using these techniques. The introduction of ultrasonic methods has widened the diagnostic capabilities of noninvasive testing. Analysis of the velocity waveform envelope using zero‐crossing detectors allows highly accurate identification of normal and severely diseased arteries. Used alone, however, this technique is limited in its ability to detect occlusions and provides no information on the energy content of the velocity spectrum. Furthermore, because it is often difficult to identify the sampling site with precision, the method does have limitations. The development of imaging techniques has helped to overcome this difficulty. While B‐mode scanning appears promising, reliance on the image alone may be misleading. By producing an acoustic shadow, calcification may in fact hide a lesion of interest. Also, the similar acoustic characteristics shared by soft plaques, thrombi, and blood make it difficult to identify accurately soft plaques and occlusions.

The addition of Doppler devices to ultrasonic imaging techniques has provided instruments that produce an image of the artery from which the flow information is collected. Methods involving the combination of a pulsed Doppler unit and an imaging system are particularly useful in detecting flow from discrete points within the vessel and prevent errors associated with flow disturbances near the wall. Errors associated with these techniques are usually the result of misidentification of vessels and tend to decrease as the examiner gains experience. Although auditory interpretation of the Doppler signal has produced good results, the quantitative analysis of the spectra represents a considerable improvement in diagnostic accuracy. Correct vessel identification and more precise quantification of the degree of narrowing can be achieved with this technique. In a research setting, the duplex technique provides a useful means of assessing the natural history of carotid artery disease before and after endarterectomy. Further improvements, such as the computer‐based velocity waveform pattern recognition technique, have shown great potential in the objective evaluation of carotid disease. Although a great deal of work remains to be done, such techniques should provide us with a better understanding of and a more rational approach to the management of atherosclerotic disease at the carotid bifurcation.
Doppler Echocardiography in Pulmonary Stenosis
Authors: MURPHY DANIEL J. , LUDOMIRSKY ACHI , DANFORD DAVID A. , HUHTA JAMES C.
Published: August 2007

Doppler ultrasound has dramatically improved the accuracy of noninvasive detection of pulmonary stenosis. Combined with careful two‐dimensional imaging, the site and severity of obstruction to pulmonary flow can be detected and quantified. Although there are some limitations to the technique, interpretive errors are avoidable with an understanding of the method and careful attention to detail during the performance of the examination. Doppler echocardiography has become a valuable adjunct to the nonsurgical treatment of valvular pulmonary stenosis and promises to provide more information for developing new management schemes in congenital heart disease.
Ultrasonic Duplex Scanning in the Evaluation of Arterial Grafts and Dilatations
Authors: BANDYK DENNIS F.
Published: August 2007

The progressive decline in patency of arterial bypasses and dilatations with time mandates a protocol of noninvasive testing for surveillance. The majority of patients requiring revision are asymptomatic and, therefore, screening with angiography is not warranted. With the development of the duplex scanner, a method is available that provides both anatomical and physiological information of arterial reconstructions. The technique permits a quantitative evaluation of the velocity waveform in arterial grafts and dilatations. Flow velocity in grafts can be calculated and used as a prognostic indicator of patency. A low graft flow velocity (peak systoloic velocity &< 45 cm/sec) indicates that graft patency is threatened and should prompt a complete evaluation. The ability to image the arterial system from the abdominal aorta to the tibial arteries permits precise localization of disease, detection of correctable graft lesions, and better selection of patients for arteriography. Approximately 5% of patent lower limb bypasses per year will be identified to have a hemodynamic abnormality that warrants correction. Duplex scanning is also ideally suited for the evaluation of transluminal angioplasty sites. Vessel patency and stenosis severity can be assessed based on the velocity spectra. Careful surveillance of arterial grafts and dilatations is rewarded by improved patency and the continued relief of limb ischemia.
Exercise Doppler Echocardiography
Authors: Wann L. Samuel , Sagar Kiran B.
Published: August 2007

Doppler echocardiography is a promising technique for evaluating left ventricular performance during exercise. The method is inexpensive and relatively simple to perform and analyze. Studies of reasonable quality can be performed even at high workloads. Peak velocity of blood flow, acceleration, and stroke volume are parameters clearly related to the function of the left ventricle and can be used to show changes due to ischemia induced by exercise.

A number of potential problems exist in applying Doppler echo to the assessment of left ventricular function. It is assumed that the interrogating beam of ultrasound is parallel to flow, and that the flow profile is relatively flat. Neither of these assumptions may be true, however, and the orientation of the ultrasound beam and flow could change during exercise. Problems exist in measuring aortic area. Deterioration of signal quality during exercise may make determination of the onset and termination of flow difficult, and outlining the flow velocity integral may be inaccurate. Despite these potential limitations, the method appears to work remarkably well. The ability to accurately detect changes in function as opposed to absolute function may be the best way to apply this method.

Further work needs to be done to establish the precise determinates of ascending aortic blood flow and their relationship to preload, afterload, and contractility. Just as ejection fraction is not a pure indicator of left ventricular contractility, neither is aortic blood flow. In particular, afterload appears to have a major influence on blood flow velocity. Further study is clearly warranted to place the results of exercise Doppler measurements of ascending aortic blood flow into clinical perspective.
Evaluation of Coronary Artery Fistula by Color‐Flow Doppler Echocardiography
Authors: LUDOMIRSKY ACHI , DANFORD DAVID A. , GLASOW PATRICK F. , BLUMENSCHEIN SARAH D. , MURPHY DANIEL J. , HUHTA JAMES C.
Published: August 2007

An asymptomatic newborn infant with a left coronary artery to right ventricular apex fistula was evaluated using color‐flow Doppler techniques. Color flow mapping during diastole showed a prominent turbulent flow signal that could be traced from the proximal left coronary artery, along the interventricular septum, to the right ventricular apex. Color flow Doppler is an important complement to two‐dimensional imaging for the identification and location of coronary artery fistulas.
Ultrasonic Tissue Characterization of Normal and Ischemic Myocardium
Authors: SAGAR KIRAN B. , PELC LORIE R. , SAEIAN KOOROUSH , RHYNE THEODORE L. , WANN L. SAMUEL , WARLTIER DAVID C.
Published: August 2007

Cardiac ultrasonic tissue characterization is designed to use the alterations in acoustic signals from the myocardium to differentiate normal from ischemic or infarcted tissue due to their characteristic backscatter attenuation. Various approaches such as use of a gray scale, color display, or quantitative image analysis has been used for tissue characterization, but all depend on subjective assessments and are not necessarily reproducible. The most promising method has been the use of “raw” radiofrequency signals and measure changes in the ultrasonic attenuation with an index of backscatter to distinguish normal from abnormal myocardium called “integrated backscatter” (IB). Various studies have demonstrated the changes in the ultrasonic backscatter with ischemia or infarction. In this review we summarize our experience with a research prototype instrument in tissue characterization and differentiation of normal, ischemic, infarcted, and post ischemic reperfused myocardium in anesthetized open chest dogs. Currently we are investigating the role of ultrasonic tissue characterization to estimate infarct size and plan to apply these observations to patients in order to detect viable myocardium and quantitate infarct size.
Evaluation of a Technique for Avoiding Inadvertent Myocardial Laceration in an Experimental Canine Model: Expansion of the Role of Two‐Dimensional Echocardiography
Authors: REEVES WILLIAM C. , JOLLY STANLEY R. , CHRISTENSEN CARL W.
Published: August 2007

An experimental animal model was utilized to evaluate the role of simultaneous two‐dimensional echocardiography combined with a modified electrocardiographic monitoring techinque for improving the safety of pericardiocentesis. This technique avoids the hazards of placing the sharp pericardiocentesis needle against the heart in order to determine its location against the epicardial surface. This technique was evaluated in eight dogs in over 100 aspiration attempts. Cardiac trauma occurred only in a single incidence with the use of a 20‐gauge cannula. A detailed description of this procedure is provided in the text.
A Reappraisal of the Mitral B‐Bump (B‐Inflection): Its Relationship to Left Ventricular Dysfunction
Authors: D'CRUZ IVAN A. , KLEINMAN DANIEL , ABOULATTA HUSSEIN , ORANDER PATRICIA , HAND R. CHRIS
Published: August 2007

A prolonged AC interval, decreased PR ‐ AC interval, and a B‐inflection (“bump” or “notch”) on the mitral AC slope, have been widely regarded as evidence of abnormally high LVEDP for the last 16 years. However, several groups have questioned the reliability of these signs as predictors of high LVEDP. In 50 patients subjected to LV catheterization, we found no correlation between LVEDP and the AC interval or PR ‐ AC interval. A better correlation was obtained between the presence of a B‐inflection and diminished LV ejection fraction on angiocardiography. In our series, the B‐inflection was noted in 1/19 patients with LVEDP < 15 mmHg as well as LV ejection fraction > 55%, but it was present in 7/10 patients with LVEDP over 15 mmHg, as well as LV ejection fraction < 55%. When properly recorded, the presence of a B‐inflection is a useful sign of significant LV dysfunction.
Impact of Transesophageal Color Flow Doppler Echocardiography in Current Cardiology Practice
Authors: CHANDRASEKARAN KRISHNASWAMY , BANSAL RAMESH C. , MINTZ GARY S. , ROSS JOHN J. , SHAH PRAVIN M.
Published: August 2007

Of 3,480 patients who were referred for cardiac ultrasound evaluation, 230 patients (6.6%) underwent transesophageal echocardiography because the transthoracic study was not feasible, technically inadequate, or provided insufficient diagnostic information for optimal patient management. There were 149 inpatients and 81 outpatients. The majority (182 patients, 79%) had aortic or mitral disorders. In 166 patients (72%), transesophageal echocardiography played a significant role in patient management. Transesophageal echocardiography was most useful in evaluating diseases of the aorta (dissection, root abscess, or aneurysm), mitral prosthesis, complications of endocarditis, left atrial appendage thrombi, and in determining the cause of mitral insufficiency. Transesophageal echocardiography was useful in the evaluation of critically ill patients and those with severe lung disease.
Partial Endocardial Cushion Defect with Aneurysm of the Anterior Mitral Leaflet in a 70‐Year‐Old
Authors: LETCHER JOHN , CHANDRASEKARAN KRISHNASWAMY , GOEL INDER , PENNOCK RONALD , ROSS JOHN , MINTZ GARY S.
Published: August 2007

Mitral valve abnormalities are commonly associated with partial endocardial cushion defect. Aneurysm of the cleft leaflet has not been described in association with partial endocardial cushion defect. This case describes the aneurysmal deformity of the cleft leaflet in a 70‐year‐old woman diagnosed by transesophageal echocardiography imaging.
Screening Tests for Intrauterine Growth Retardation: A Comparison of Umbilical Artery Doppler to Real‐Time Ultrasound
Authors: LOWERY CURTIS L. , GOLDENBERG ROBERT L. , BAKER RACHEL C. , MEHTA RAJENDRA , WAN JIM , DAVIS RICHARD O. , BRUMFIELD CYNTHIA G. , HOFFMAN HOWARD J.
Published: August 2007

In a study designed to compare Doppler umbilical artery velocimetry to ultrasound morphometric measurements in the prediction of intrauterine growth retardation, 636 paired ultrasound and Doppler umbilical artery examinations were performed between 24 and 40 weeks gestational age. Intrauterine growth retardation was defined as birth weight less than the tenth percentile per gestational age and 25 (9.2%) of the infants born in our study met this criteria. In general, when the gestational age was limited to <30 weeks, none of the tests were highly predictive of intrauterine growth retardation. Doppler umbilical artery systolic‐to‐diastolic ratios of >3 had the highest sensitivity. However, due to inclusion of a large number of false‐positives, it was considered a poor test. After 30 weeks, fetal abdominal circumference less than the tenth percentile had a greater sensitivity (45%) and positive predictive value (28%) than Doppler systolic‐to‐diastolic ratios >3 (36% and 18%, respectively). Doppler ultrasound umbilical artery systolic‐to‐diastolic ratios are not more predictive of intrauterine growth retardation than ultrasound morphometric measurements.
Intraoperative Echocardiography in Cardiac Emergencies
Authors: MOHL WERNER , SIMON PAUL , NEUMANN FRIEDERIKE
Published: August 2007

Echocardiography has brought about a new modality of surgical decision making in open heart surgery. Especially in urgent and emergency surgery, echocardiography can provide decisive insight into the underlying pathophysiological processes, improved monitoring of cardiac function, as well as immediate quality control after the procedure. The importance of intraoperative echocardiography for the cardiac surgeon is illustrated in a number of selected case reports.
Intraoperative Evaluation of Valvular Regurgitation: Comparison of Echocardiographic Techniques
Authors: GOLDMAN MARTIN E. , GUARINO THERESA , MINDICH BRUCE P.
Published: August 2007

Intraoperative echocardiography provides information on cardiac structure and function that is unobtainable from routine monitoring modalities. Intraoperative imaging can be performed from the epicardial and/or transesophageal approach, and with the addition of contrast and/or color flow Doppler mapping, blood flow characteristics within the cardiac chambers can be visualized. The relative severity of regurgitation can be assessed before and after valvular surgery, and before the patient leaves the operating room, thereby facilitating successful valve repair or replacement. Surgeon preference, equipment availability, and valvular pathology will determine which technique will be utilized.
Intraoperative Echocardiography in Mitral and Tricuspid Valve Repair
Authors: CZER LAWRENCE S.C. , MAURER GERALD
Published: August 2007

Echocardiography with Doppler color flow mapping is a very useful intraoperative technique in patients undergoing mitral or tricuspid valve repair. In the patient who is a repair candidate, this technique can be used intraoperatively to answer important clinical questions: the severity of the regurgitation; the morphological basis of the regurgitant lesion; and the feasibility of repair. Other important issues such as the impact of physiological interventions on regurgitation severity, the presence of associated lesions, and the state of ventricular function can also be addressed. In the patient who has undergone a valve repair, this technique can be used intraoperatively prior to chest closure to assess the adequacy of the repair procedure and to detect associated complications such as outflow tract obstruction.
Transvascular and Intracardiac Two‐Dimensional Echocardiography
Authors: SEWARD JAMES B. , KHANDHERIA BIJOY K. , MCGREGOR C.G.A. , LOCKE T.J. , TAJIK A. JAMIL
Published: August 2007

Recent developments in transesophageal and catheter‐based ultrasound instrumentation have allowed invasive ultrasound imaging. This experimental study presents a new application of invasive ultrasound, transvascular and intracardiac ultrasound imaging. In six pigs, we introduced a 7‐mm, 5‐MHz esophageal ultrasound probe into both the abdominal aorta and inferior vena cava and explored the imaging potential of this approach. Transvascular imaging from the aorta allowed visualization of the various cardiac structures, the neural canal and interspaces, and peritoneal anatomy. Advancement of the transducer to the level of the aortic valve or into the left ventricle yielded images of the cardiac valves and chambers. With transvascular imaging from the inferior and superior vena cava, the aorta, neural canal, pancreas, and liver were well visualized. Intracardiac imaging from the inferior venae cavae and various regions of the right heart, the left heart structures could be visualized. This in vivo feasibility study demonstrates the potential application of transducer‐tipped catheters for transvascular and intracardiac imaging.
Intravascular Ultrasound Imaging and Three‐Dimensional Modeling of Arteries
Authors: BURRELL C.J. , KITNEY R.I. , ROTHMAN M.T.
Published: August 2007

In this article, we describe the reconstruction of arterial structures using solid modeling. The alternative approaches to three‐dimensional modeling are discussed and the voxel space system we use for intra‐arterial imaging, based on ultrasonic data, is described. The complete three‐dimensional ultrasonic imaging system comprising a purpose‐built, catheter‐mounted ultrasound probe, ultrasonic transceiver, and computer system is presented. This system has been used to recreate three‐dimensional computer models of arterial sections in vitro and in vivo. Examples to illustrate the power and flexibility of voxel space modeling in terms of postprocessing and software manipulation are given. Preliminary work on tissue differentiation, using arterial models and color coding of the image, and three‐dimensional presentation of flow data is included.
Percutaneous Coronary Angioscopy: Methods, Findings, and Therapeutic Implications
Authors: WHITE CHRISTOPHER J. , RAMEE STEPHEN R.
Published: August 2007

The development and clinical implementation of percutaneous coronary angioscopy represents an engineering triumph, blending the newest technologies and materials in the field of fiberoptics with the most advanced techniques of balloon angioplasty catheter materials and construction. Current devices provide a safe method for acquiring excellent quality images of the coronary arteries. This is due to major advances in catheter alignment techniques allowing coaxial positioning of the angioscope in the relatively tortuous coronary arteries. Additional development is needed to further refine the degree of operator control over the field of view, which would also reduce procedure duration. The percutaneous coronary angioscope is currently a functional device for investigators attempting to correlate the morphology of atherosclerotic lesions and clinical coronary artery disease. Confirmation of the value of the angioscope as a clinically useful device for routine application in the diagnosis and management of cardiovascular disease will depend upon the results of further studies.
Echocardiographic Identification of Type I Truncus Arteriosus in an Adult
Authors: BROOKS S. ROLAND , NANDA NAVIN C. , CHANG LEANG‐KAI , COPELAND ROBERT B.
Published: August 2007

The right parasternal view and recognition of flow acceleration and convergence are important aspects of routine two‐dimensional color Doppler echocardiography. This case illustrates their importance in the echocardiographic identification of Type I truncus arteriosus in one of the oldest reported living adults with this congenital abnormality.
Utility of Doppler Echocardiography in the Evaluation of Aortic Homograft Valved Conduit Function in Children: Need for Segmental Conduit Interrogation
Authors: MARCUS BARRY , LEWIS ALAN B.
Published: August 2007

To assess the utility of Doppler echocardiography in evaluation of aortic homograft valved conduit function, 10 consecutive pediatric patients had Doppler examination of aortic homograft valved conduits associated with follow‐up cardiac catheterization. General correlation was found between the Doppler‐derived peak systolic pressure gradient across the aortic homograft valved conduit and cardiac catheterization (r = 0.65, P < 0.05, SEE = 20.5). One patient with multilevel obstruction had significant underestimation of gradient by Doppler due to incomplete segmental interrogation of the aortic homograft valved conduit. For the other nine patients with complete segmental conduit interrogation, correlation between Doppler and cardiac catheterization was excellent (r = 0.93, P < 0.01, SEE = 10). Conduit insufficiency in nine out of ten patients was graded qualitatively using Doppler color flow mapping with excellent correlation between color flow mapping and cardiac catheterization (rS= 0.98) Aortic homograft valved conduit function can be accurately noninvasively assessed by Doppler but proximal, valve, and distal conduit segmental interrogation is necessary to localize site of obstruction if present, rule out multilevel obstruction, and avoid underestimation of systolic gradient.
Intravascular Ultrasound Evaluation of Iliac Stents One Year Following Laser‐Assisted Angioplasty
Authors: DIETHRICH EDWARD B. , FERRAZ DA CUNHA E SA DIOGO IVENS
Published: August 2007

With the proliferation of sophisticated endovascular interventions, the need for more definitive assessment of preprocedural and postprocedural pathology and long‐term outcome is acute. A new technique, intravascular ultrasound imaging, was used to provide a 1‐year evaluation of iliac artery stents in a patient whose renal insufficiency contraindicated protocol‐mandated arteriography. The sonogram provided adequate visualization of the functional status of the stents through cross‐sectional measurements and the intimal response to the devices. This represents the first use of intravascular ultrasound imaging for long‐term evaluation of iliac stents.
Doppler Velocimetry of the Umbilical and Uteroplacental Circulation: A Critical Review
Authors: SCHULMAN HAROLD
Published: August 2007

During the past 8 years, there have been more than 300 articles published describing Doppler studies in the field of obstetrics. This review will analyze the data dealing with the umbilical and uteroplacental circulation. This is being done with the goal of formulating an opinion of the role of Doppler in the practice of clinical obstetrics. We have concluded from prospective studies that there is no clear definition of abnormal umbilical flow velocity before 30 weeks, except for absent end‐diastolic velocity after the 20th week. Most of the prospective studies on the uteroplacental circulation have suffered from a lack of knowledge of the umbilical circulation, or only one uterine artery was studied. Most investigations until now have focused on demonstrating the pathophysiological correlations with Doppler studies. With the exception of a few dissenting voices, most have demonstrated strong correlations at probability levels of < 0.01. A few studies have emerged that have attempted to evaluate Doppler as a screening or surveillance tool. The results have not been encouraging. In populations with a low perinatal mortality, it will be difficult to prove that Doppler will reduce perinatal mortality. Studies of Doppler efficacy will have to be designed to show improved usage and efficacy of fetal surveillance. Since Doppler uniquely identifies the fetus at risk for hypoxia before term, it could replace our current risking system for the detection of fetal disease. This implies a reduction in the need for serial nonstress test, contraction stress test, and ultrasounds for amniotic fluid volume in those pregnancies with normal uterine and umbilical flow velocity.
Study by Doppler Ultrasonography of the Effect of Smoking on the Fetal and Maternal Circulations
Authors: EXOJO L. FITE , PONS P. J. TORRES I , VERET A. RODRIGUEZ , BRU C. , MERLO J. GONZALEZ
Published: August 2007

Forty healthy pregnant women with a normal pregnancy between 24 and 36 weeks of gestation and who were habitual smokers were studied. The changes produced by cigarette smoking on fetal‐maternal circulation were observed using Doppler ultrasonography (Duplex scanning). Twenty minutes after smoking the resistance index in different vascular territories and the fetal and maternal heart rates were measured. Statistically significant increases in heart rates as well as in the resistance index of the umbilical and anterior cerebral arteries were obtained; these could be due to an increase in the vascular resistance of the placenta (umbilical arteries) or to a vasoconstriction in these vessels (umbilical and cerebral). No increase in the resistance index in the uterine artery suggesting vasoconstriction with decreased utero‐placental flow was observed.
Umbilical Artery Flow Velocimetry after 40 Weeks of Amenorrhea
Authors: de ROCHAMBEAU B. , RUDIGOZ R.C. , MELLIER G. , DARGENT D.
Published: August 2007

This study involved 80 single, uncomplicated pregnancies, with term exactly confirmed by sonogram before 17 weeks of amenorrhea. All delivery data was recorded, and the neonates were examined by a pediatrician. All the umbilical resistance indices from day 280 to day 300 of gestation were constant and equal to R = 0.52 ± 0.041 (mean ± standard deviation), the rates of perinatal distress and postmaturity increased with the prolongation of gestation. All of the postmature neonates, acidotic neonates, and 12 out of 14 fetal heart rate anomalies observed in the study occurred above R = 0.54. Our results suggest that assessment by umbilical artery flow velocimetry of postdates fetuses is more efficient than the nonstress test, and simpler than the contractions stress test and biophysical profile.
Umbilical Arterial Doppler Indices in Acute Uteroplacental Flow Occlusion
Authors: MAULIK DEV , DOWNING GREGORY J. , YARLAGADDA PRASAD
Published: August 2007

This study was undertaken to investigate in an acute model the effects of acute transient occlusion of the uterine blood flow on the umbilical arterial Doppler indices. Transient uteroplacental circulatory insufficiency was produced in five pregnant ewes (gestational age 115–120 days) by reversible mechanical occlusion of the common hypogastric artery for 20 seconds. The Doppler indices measured were the systolic‐diastolic ratio, the pulsatility index and the resistance index. The duration of the cardiac cycle and its systolic and diastolic times were approximated from the Doppler waveform. The occlusion produced transient increases in the Doppler indices and cardiac cycle time. The uteroplacental circulatory insufficiency induced increases (P < 0.005) in the Doppler indices disappeared (P > 0.05) when the latter were corrected for the changes in the cardiac cycle time. Furthermore, diastolic time was the main component of the changes in the cardiac cycle time, and the Doppler indices demonstrated a higher correlation with diastolic time than with systolic time. The results verified that changes in the duration of the fetal cardiac cycle play an important role in shaping the umbilical arterial Doppler waveform and hence need to be taken into account in estimating the Doppler indices.
Long‐Term Doppler Ultrasound Measurement Through the Anterior Fontanel in Neonates: Choice of Parameter for Computer Supported Analysis
Authors: KALJU KERSTI , KIRSCH WERNER , BRESSER BERTRAM , GROHS BERND
Published: August 2007

There is no easy comparison of the Doppler spectra. Therefore, determining parameters is necessary for long‐term measurements. A manual analysis is laborious, limits the number of possible examinations, and considerations are restricted to the envelope curve (maximal cerebral blood flow velocity). The applied ultrasonic apparatus (a modified HP 77020AC) determines three waveforms besides the Doppler spectrum: Vmax as maximal, V mean as average, and V mode as the most frequently measured velocity. These data are directly transferred to a PC. Using low Doppler intensity Vmax resulted in values up to 39% lower than determined by manual analysis because of the apparatus' algorithm. By use of higher Doppler intensity this difference was reduced to 19%. Regarding clinical validity, the Vs mean seemed to be the best parameter for further processing. Determining peak systolic velocity (V mean), end‐diastolic velocity (Vd mean), and mean velocity over time (V̄ mean) were selected for standard analysis. The Pourcelot index was not taken into account, first for lack of definition for V mean and secondly for not missing simultaneous changes of the peak systolic and the end‐diastolic velocity.
Does Pulsed‐Doppler Ultrasound Have Mutagenic Effects? Application of the Ames Mutagenicity Assay to Test Pulsed‐Doppler Equipment
Authors: MEYENBURG MICHAEL , LANG RAINER , SALING ERICH , WEGNER ROLF‐DIETER
Published: August 2007

Measurement of fetal blood flow has been accepted using pulsed‐Doppler ultrasound. Until recently, there has been a lack of investigations concerning the potential risks of this method. The possible mutagenic effect of a pulsed‐Doppler system was examined in vitro by applying the Ames test. Tester strains of Salmonella typhimurium indicating point mutations were irradiated (TA 98, TA 100, TA 102, TA 1535, TA 1537, TA 1538). A commercially available duplex system was applied in the experiments emitting an ultrasound beam with a spatial‐peak temporal‐average of 5.2 mW/cm2 and a spatial‐peak temporal‐peak of 117 mW/cm2 at a frequency of 2 MHz. The tester strains were sonicated up to 60 minutes, the bacterial suspension being in direct contact with the transducer surface. The ultrasound‐exposed bacterial suspensions were compared with nonexposed samples. Reference mutagens were used for checking the sensitivity of the system. The results do not indicate any mutagenic effects.
Use of the Smaller Pediatric Transesophageal Echocardiographic Probe in Adults
Authors: HELMCKE FREDERICK , III EDWARD F. MAHAN , NANDA NAVIN C. , COOPER JOHN W. , SANYAL RAJATSUBHRA
Published: August 2007

Transesophageal echocardiography in the adult uses a relatively large diameter probe, which may be poorly tolerated by certain patients. The use of a smaller probe designed for pediatric patients was studied in 50 adults (21 males and 29 females), and concomitant transesophageal echocardiography studies were performed using the regular adult‐sized probe in 28 of these patients. The smaller pediatric transesophageal echocardiography probe was easier to pass, better tolerated, caused a smaller heart rate increase (13 ± 3 vs 20 ± 4 beats/min, P = 0.0029), and required no sedation in more patients than the adult transducer. The resolution of the two‐dimensional and color Doppler images in the mid and near fields of the smaller probe were comparable to the larger probe, as were the maximal area of mitral regurgitation and the ratio of the maximal proximal width of the aortic insufficiency jet to the left ventricular outflow tract diameter in patients with these lesions. However, the image resolution was noticeably inferior to the adult probe in the far field, such as when imaging the distal left ventricle or imaging structures transgastrically. Therefore, the smaller probe designed for pediatric use allows satisfactory near‐ and mid‐field two‐dimensional and color Doppler flow imaging in comparison to the adult probe and would be expected to be beneficial in adult patients in whom superior quality imaging of the far‐field is not required clinically, those who tolerate poorly the adult probe, relatively high‐risk patients in whom no sedation is desirable, and in those patients in whom passage of the larger probe is unsuccessful.
Problems and Pitfalls in the Performance and Interpretation of Color Doppler Flow Imaging:
Authors: RAO SUNDER RAM , RICHARDSON S. GEOFFREY , SIMONETTI JANET , KATZ SARAH E. , CALDEIRA MARJORY , PANDIAN NATESA G.
Published: August 2007

Color Doppler flow imaging has become an integral part of the echocardiographic examination. By providing real‐time, two‐dimensional spatial maps of normal and abnormal cardiac blood flows, this technique provides important information that may be used to guide patient management. The acquisition and display of color Doppler flow information may be influenced by technical factors, by the physiological condition of the patient, by abnormalities of cardiac morphology, and, on occasion, by artifact. In this article, the results of a study performed to evaluate the influence of technical factors on the color Doppler assessment of mitral regurgitation are reported. Mitral regurgitation jet area size changed significantly with variation in the control settings for color gain, color process, color map, color image resolution, and sector width. A review of those factors that influence the performance and interpretation of the color Doppler flow examination is provided and their significance discussed.
Real‐Time, Intracardiac, Two‐Dimensional Echocardiography
Authors: PANDIAN NATESA G. , KUMAR ROHIT , KATZ SARAH E. , TUTOR ALI , SCHWARTZ STEVEN L. , WEINTRAUB ANDREW R. , GILLAM LINDA D. , McKAY RAYMOND G. , KONSTAM MARVIN A. , SALEM DEEB N. , ARONOVITZ MARK
Published: August 2007

Advances in catheter‐based ultrasound imaging technology allow for a unique opportunity to develop two‐dimensional intracardiac echocardiography, an imaging method that could have significant clinical applications. In this study, we evaluated the potential of a new, percutaneous, 9‐Fr prototype intracardiac echocardiographic catheter with a 12.5‐MHz rotating crystal in 13 dogs. In all dogs, we were able to easily advance the intracardiac echocardiographic catheter into the right and left hearts percutaneously and obtain dynamic images of cardiac structures in various imaging planes. With the intracardiac echocardiographic catheter in the right atrium, the whole chamber could be visualized. Minor manipulation allowed visualization of the right atrium, right ventricle, and tricuspid valve in a two‐chamber view; further maneuvering yielded four‐chamber views. With advancement of the catheter into the right ventricle and pulmonary artery, the right ventricular cavity, right ventricular outflow tract, and pulmonary artery could be imaged. The intracardiac echocardiographic catheter in the aortic root allowed visualization of the pulmonary artery and its bifurcation, superior portions of the atria, interatrial septum, aortic valve, and the proximal left coronary artery. With the intracardiac echocardiographic catheter in the left ventricle, short‐axis images of the whole left ventricle were obtained. Manipulating the catheter tip within the left ventricle, we could visualize the left ventricle, left atrium (LA), and the mitral valve in the long axis. We were also able to visualize and identify experimentally‐induced ischemic regional left ventricular dyskinesis (four out of five dogs), aortic valvular tear (five out of five dogs), and pericardial effusion with right atrial collapse (two out of two dogs). Intracardiac echocardiography was not associated with any complications. We conclude that percutaneous, low‐frequency intracardiac echocardiography with a 12.5‐MHz, 9‐Fr catheter yields cardiac images in many imaging planes with a good depth of field, allows identification of valvular, myocardial, and pericardial abnormalities, and has excellent clinical potential in the assessment of many cardiovascular disorders. (ECHOCARDIOGRAPHY, Volume 8, July 1991)
Color Flow Doppler Observations on Mitral Valve Flow in Tamponade
Authors: SAXENA RISHI K. , D'CRUZ IVAN A. , LITAKER MARK
Published: August 2007

We studied the M‐mode and two‐dimensional imaging of color Doppler mitral flow in eight patients with pericardial effusion and tamponade, and in ten control subjects. Pulsed‐Doppler recordings of mitral flow were also obtained in all. Marked phasic changes (presumably respiratory) were consistently recorded in all patients with tamponade with respect to brightness, hue, width (duration), and length of the M‐mode Doppler color stream; in these patients, phasic changes were noted in width, length, and color of the mitral flow stream on the two‐dimensionalechocardiographic recording, with reciprocal changes in tricuspid flow. In the normal subjects, only minimal fluctuations in these color Doppler characteristics were present. Phasic differences in flow velocity of mitral flow by pulsed Doppler were found between the tamponade and the control groups. Large phasic fluctuations in various characteristics of color Doppler mitral flow on M‐mode and two‐dimensional imaging may constitute yet another echocardiographic sign of tamponade. (ECHOCARDIOGRAPHY, Volume 8, September 1991)
The Physiology of Congenital Heart Disease: Assessment by Doppler Color Flow Mapping
Authors: SOMMER ROBERT J. , RITTER SAMUEL B.
Published: August 2007

The use of Doppler echocardiography is a routine part of the noninvasive assessment of the patient with heart disease. In children with congenital heart disease, pulsed‐ and continuous‐wave Doppler echocardiography techniques provide accurate, reproducible hemodynamic data relative to structural defects. Doppler color flow imaging, however, allows for qualitative assessment of blood flow patterns, which may give important insights into the changing physiology of the newborn infant or that of a patient in the medical or surgical intensive care settings. Ten cases are presented in which this flow information is instructive in understanding the physiological sequelae of congenital heart disease. (ECHOCARDIOGRAPHY, Volume 8, September 1991)
Quantification of Mitral Regurgitation: Comparison Between Transthoracic and Transesophageal Color Doppler Flow Mapping
Authors: MIMO RENATA , SPARACINO LINA , NICOLOSI GIAN L. , D'ANGELO GIOVANNI , DALL'AGLIO VITTORIO , LESTUZZI CHIARA , PAVAN DANIELA , CERVESATO EUGENIO , ZANUTTINI DOMENICO
Published: August 2007

We reviewed transthoracic (TTE) and transesophageal (TEE) echocardiograms of 100 consecutive patients: 63 male, 37 female, mean age 50 years (range 16–83 years), 32 with neoplastic disease, 18 aortic disease, 28 mitral valve disease, and 22 with other diseases. Absence or presence of mitral regurgitation (defined as mild, moderate, or severe) was assessed. TEE showed mild mitral regurgitation in 26 patients where TTE was negative. The overall estimate of regurgitant lesion severity was concordant at TEE and TTE in 64% of cases. The overall estimate of regurgitant lesion severity was also greater by one grade in 1% of cases at TTE, and in 35% of cases at TEE. Maximal digitized jet areas were 3.60 ± 6.35 cm2at TTE and 3.04 ± 3.79 cm2at TEE (P = NS). Correlation was r= 0.69 (TEE = 0.41 TTE + 1.55; P< 0.001). TEE yielded a higher prevalence of mitral regurgitation than TTE with a trend toward greater overall estimate of mitral regurgitation at the semi‐quantitative analysis. TTE and TEE showed similar mean results at the quantitative assessment of maximal jet areas. However, a highly significant random variability was observed in quantifying mitral regurgitation at TEE. (ECHOCARDIOGRAPHY, Volume 8, November 1991)
Panoramic Transesophageal Echocardiography
Authors: HSU TSUI‐LIEH , WEINTRAUB ANDREW R. , RITTER SAMUEL B. , PANDIAN NATESA G.
Published: August 2007

Panoramic transesophageal echocardiography is a new development in transesophageal echocardio‐graphic (TEE) technology, which yields a wide‐angle imaging field for real‐time two‐dimensional and color flow imaging. We report our early experience in patients with the use of an annular‐array TEE probe that provides a wide, 270° angle imaging field for two‐dimensional echocardiography imaging. The field of view can, however, be narrowed to 15°. The field of view for color flow imaging can be varied from 180° to 10°. Pulsed‐Doppler recordings of flow velocity are also possible. This TEE system provides a panoramic vision of cardiac and paracardiac structures from the esophagus and stomach. Besides cardiovascular structures, other thoracic and upper abdominal organs can be visualized. The wide field of view allows a better comprehension of the cardiac anatomy and its relationship with adjacent structures. The initial experience suggests that this method, besides providing the usually required diagnostic information, may have a number of additional applications. Its clinical potential and directions for future developments are reviewed. (ECHOCARDIOGRAPHY, Volume 8, November 1991)
Evaluation of Mitral Regurgitation by Doppler E chocar diogr aphy
Authors: CASTELLO RAMON , LABOVITZ ARTHUR J.
Published: August 2007

The diagnosis and assessment of mitral regurgitation has been one of the main challenges for cardiac ultrasound. Imaging techniques (M‐mode and two‐dimensional echocardiography) provide direct morphologic and etiologic information of the evaluation of patients with suspected mitral regurgitation. The advent of cardiac Doppler increased tremendously the ability to evaluate mitral regurgitation noninvasively. Continuous‐wave and pulsed Doppler have been found to be sensitive and specific in the detection of mitral regurgitation. The introduction of color flow Doppler simplified enormously the assessment of patients with suspected mitral regurgitation. The maximal regurgitant area and maximal regurgitant area corrected for left atrial size have become the most commonly used parameters to evaluate mitral regurgitation by color flow Doppler in the clinical setting. However, the color regurgitant jet area is highly dependent on anatomical, hemodynamic, and equipment factors. A new method, based on the proximal isovelocity surface area, is being evaluated and appears to be relatively independent of equipment factors. Transesophageal echocardiography has been shown to be exquisitely sensitive in the detection of mitral regurgitation. Quantitation of mitral regurgitation by transesophageal echocardiography is currently based on the maximal regurgitant area and this parameter appears to correlate closely with the angiographic degree of mitral regurgitation. Pulmonary venous flow analysis had been used in conjunction with color flow mapping for the evaluation of mitral regurgitation by transesophageal echocardiography. The presence of reversed systolic flow has been shown to be sensitive and specific for the diagnosis of severe mitral regurgitation. Patients with clinically difficult surface studies, flail mitral valve leaflets, and prosthetic mitral valve are best evaluated by the transesophageal approach with interrogation of pulmonary venous flow. (ECHOCARDIOGRAPHY, Volume 8, November 1991)
Future Technical Prospects in Biplane Transesophageal Echocardiography: Use of Adult and Pediatric Biplane Matrix Probes
Authors: OMOTO RYOZO , KYO SHUNEI , MATSUMURA MAKOTO , MARUYAMA MASANOBU , YOKOTE YUJI
Published: August 2007

This study evaluates the feasibility of the combined use of an adult matrix probe with a real‐time biplane imaging system, and also describes the performance of a newly developed pediatric matrix probe. (ECHOCARDIOGRAPHY, Volume 8, November 1991)