Pro: intraoperative transesophageal echocardiography is a cost-effective strategy for cardiac surgical procedures

TEE is an expensive but useful intraoperative diagnostic strategy for cardiac surgical procedures. It can alter surgical management with tremendous potential benefits to the patient. It also has the potential to avoid unnecessary surgery and reduce the risk of complications such as reoperation, thromboembolism, and stroke. As with any new technology, the indications for its use must be evaluated on the basis of cost, benefits, and efficacy to determine the true value and cost-effectiveness in a particular application. Based on the information presented in this report, it can be concluded that TEE is a cost-effective strategy for valvular and congenital heart repairs. Current data are very convincing that TEE has the potential to be cost-effective in reducing the risk of stroke in selected populations of cardiac surgical patients. As experience with the use of TEE in its various applications increases and the technology itself continues to improve, it will undoubtedly become a more valuable and cost-effective strategy for cardiac surgery.     

Preoperative diagnosis of a patent foramen ovale: rational use of transthoracic and transesophageal contrast echocardiography

BACKGROUND: The detection or ruling out of a patent foramen ovale (PFO) can be determined noninvasively by contrast echocardiography (CE). The transesophageal technique is superior to the transthoracic technique regarding sensitivity, whereas the specificity of both methods is equally high. This prospective study shows the rational use of transesophageal CE for the detection of a PFO, in patients without cardiovascular disorders. METHODS: 165 patients (92 female, 73 male, age 48 +/- 18 years) with planned neuro-surgery in a sitting position, underwent CE to rule out a PFO. If the CE was positive, an alternative position was selected in order to avoid a paradoxical air embolism. RESULTS: Initially, a transthoracic CE was performed in all patients resulting in 21 patients (13%) being positive and 39 patients (24%) being negative by sufficient image quality. A transesophageal CE was performed in 96 of the remaining 105 patients (63%). Here, further 25 patients showed a positive CE in the sense of a PFO. The combined use of transthoracic and transesophageal CE revealed a PFO in 46 of 165 patients (28%). CONCLUSION: The use of both, transthoracic and transesophageal CE is an efficient approach to the preoperative detection of a PFO in the sense of quality and economics. Depending upon the image quality, the use of a transesophageal examination could be avoided in one third of the cases.     

The comparative value of transesophageal and transthoracic echocardiography before and after percutaneous mitral balloon valvotomy: a prospective study

Transthoracic (TTE) and transesophageal echocardiography (TEE) were performed prospectively on 53 consecutive patients (mean age 59 +/- 14 years) immediately before and within 24 hours of mitral balloon valvotomy to compare the relative value of the two techniques. Biplane TEE was used in 38 patients and single-plane imaging was done in 11. All patients underwent left and right cardiac catheterization, left ventriculography, and coronary angiography. While TEE provided excellent images of the mitral valve in all patients, imaging planes were more limited than by TTE. Mitral valve morphology could be assessed satisfactorily by either technique. Echo scores derived from each showed good correlation (r = 0.90, p < 0.001). TEE transgastric longitudinal scanning provided superior detail of the subvalvar apparatus but only in 20 (53%) of 38 patients. Patients with good transgastric views had significantly smaller left atrial volumes than those without (58 +/- 22 vs 106 +/- 41 cm3, p < 0.001). Mitral valve orifice and the commissures were better assessed by TTE. Before valvotomy, mitral regurgitation (MR) graded by TEE and TTE color flow mapping was concordant with angiography in 80% and 81%, respectively. After valvotomy, TTE color flow mapping failed to detect MR in two of the three patients who developed severe MR. Two of these patients were examined by TEE, which demonstrated both the MR jets as well as leaflet tears. Thrombus was diagnosed in the left atrium in eight patients by TEE and in only one patient by TTE. Biplane TEE was required for accurate thrombus localization and for assessing its size and extent. Five patients with thrombus underwent balloon valvotomy without complications. Left-to-right atrial shunting was detected by TEE and TTE in 95% and 48% of patients, respectively. Flow convergence regions, from which quantitative flow information can be derived, were imaged by TEE only. TTE and TEE have complementary roles. However, TEE is essential for excluding thrombus in the left atrium before balloon valvotomy. After the procedure, TEE is recommended for the evaluation of patients with severe mitral regurgitation.     

Transnasal transesophageal echocardiography: a modified application mode for cardiac examination in ventilated patients

In 42 endotracheally intubated patients, we examined the utility of a miniaturized monoplane probe for transnasal transesophageal echocardiography (TEE). Transnasal TEE was prospectively evaluated in 26 deeply and 16 mildly sedated patients receiving topical anesthesia with lidocaine jelly 2%. The patients with deep sedation were additionally examined with transoral monoplane and multiplane TEE. Transnasal esophageal insertion of the TEE probe was successfully performed in 90% of patients. Endotracheal malpositioning was corrected in two patients. Nasal bleeding required treatment in another patient. Topical anesthesia was adequate in 82% of mildly sedated patients. Left ventricular short- and four-chamber long-axis views of good quality were obtained with transnasal (transoral) monoplane TEE in 76% (81%) and 92% (96%) of patients (differences not significant). Compared with conventional multiplane TEE, transnasal monoplane TEE missed diagnoses in 19% of patients. The relative error (mean +/- SEM) of quantification with transnasal TEE was <9% +/- 2% for ventricular diameters and <7% +/- 2% for cross-sectional area measurements, with a bias of 0.5 +/- 3.8 cm2 and 0.1 +/- 2.4 cm2 (mean +/- 2 SD) for left ventricular end-diastolic and end-systolic short-axis areas. The relative error in measuring intracardiac flow velocities was >40%, but systolic to diastolic peak velocity ratios at the valvular site were determined with an error <4% +/- 3%. Transnasal monoplane TEE can be performed even in mildly sedated patients with an endotracheal tube without further need for analgesia or sedation. The technique is as useful as conventional transoral TEE to image standard tomographic planes for quantification, but it is less suited for comprehensive echocardiographic diagnosing. Implications: Transnasal insertion of a miniaturized monoplane transesophageal echocardiography (TEE) probe was studied in endotracheally intubated patients. Nasal passage was well tolerated even by patients with only mild sedation. Imaging quality was similar to conventional transoral monoplane TEE with larger transducers, but technical restraints cause a deficit in complete cardiac diagnosing obtained with multiplane TEE.     

Myocardial ischaemia un-masked by transesophageal atrial pacing combined with two-dimensional transthoracic echocardiography in a pediatric patient: a case report

The effect of growth hormone (GH) on subclinical disease activity in a 15-year-old boy with previously quiescent lupus nephritis and chronic renal failure is described. Institution of supraphysiological doses of GH resulted in a rise in erythrocyte sedimentation rate, decrease in serum complement, rise in anti-DNA antibody titers, and increase in T-cell activation markers, all of which improved following cessation of GH treatment.     

Determination of pretest probability for detection of a cardiovascular source of emboli by transesophageal echocardiography using clinical and transthoracic echocardiographic data

Transesophageal echocardiographic findings and their effect on disease management were evaluated in 216 patients with suspected cardiovascular source of emboli. Clinical and transesophageal echocardiographic findings were useful in defining pretest probability for finding a probable cardiovascular source of emboli on transesophageal echocardiography.     

Right ventricular dysfunction in low output syndrome after cardiac operations: assessment by transesophageal echocardiography

BACKGROUND: Low output syndrome after cardiac operations is associated with high morbidity and mortality rates. The contribution of right ventricular dysfunction to this syndrome has not been fully characterized. The purpose of this study was to evaluate the utility of transesophageal echocardiography to identify the frequency and the in-hospital mortality from right ventricular dysfunction in patients with this syndrome. METHODS: Seventy-five consecutive patients undergoing transesophageal echocardiography for low output syndrome early after cardiac operations were evaluated. The findings from transesophageal echocardiography were correlated with the type of surgical procedure, cross-clamp time, right heart hemodynamics, and coronary angiography. RESULTS: Right ventricular systolic dysfunction occurred in 36 patients (42%); in 17 patients it was isolated and in 19 patients it occurred in combination with left ventricular dysfunction. Postoperative right ventricular dysfunction was not uniformly associated with important right coronary artery disease or with prolonged ischemic time during cardiopulmonary bypass. Hemodynamic data were not useful to distinguish the group with postoperative right ventricular dysfunction. Patients with right ventricular dysfunction had a high (44%) in-hospital mortality rate. CONCLUSIONS: Right ventricular dysfunction occurs frequently in patients with low output syndrome after cardiac operations and is associated with a high in-hospital mortality rate. Better understanding of the mechanisms causing postoperative right ventricular dysfunction may provide insight for preventing this complication.     

Value and limitations of transesophageal echocardiography in infective endocarditis

Echocardiography has contributed considerably to the evolution in the management of patients with infective endocarditis. There is a clear hierarchy with respect to sensitivity of the different methods is superior when compared to 2-D and M-mode echocardiography in identifying both vegetations and perivalvular complications e.g. abscess formation, aneurysms, mural endocardial lesions. For patients with suspected endocarditis, in whom vegetations can not be clearly identified or in whom abscess formation is suspected with transthoracic echocardiography (TTE), transesophageal echocardiography (TEE) with mono- or multiplane scans has become the standard diagnostic procedure. For the examination of prosthetic valves it is the method of choice. It has even been suggested that it is employed as routine measure in all patients with suspected infective endocarditis. TEE is a safe semi-invasive technique with an extremely low complication rate and high sensitivity. Its specificity depends largely on the patient group which is examined. In patients with indicative clinical symptoms the specificity and the predictive value of vegetations are high. When used as screening method to assess echodense formations at cardiac valves particularly in the elderly, in whom degenerative changes prevail, its specificity and positive predictive value of vegetation-like structures are much lower. The negative predictive value of a negative transesophageal echocardiogram remains high, however. Valve abscesses are detected rarely by transthoracic echocardiography. It is the domain of TEE to assess them particularly in the aortic and mitral valve area. For them the specificity and positive predictive value of TEE in the diagnosis of infective endocarditis is high again. Of further importance was the observation that patients with vegetations of > 10 mm were more likely to suffer embolic complications. It should be noted, however, that infective endocarditis remains a clinical diagnosis: neither is the demonstration of a vegetation already the equivalent of endocarditis, nor does missing vegetations completely rule out the possibility of it. But without doubt, the presence of vegetations, of abscess formation or a concomitant pericardial effusion add valuable information to clinical diagnosis of infective endocarditis, which still needs a "high index of suspicion".     

Usefulness of transesophageal echocardiography in predicting mortality and morbidity in stroke patients without clinically known cardiac sources of embolus

Shoulder pain is encountered commonly in older people. Most of the conditions are amenable to nonoperative treatment, but a clear understanding of the anatomy and those conditions encountered most commonly is essential. A careful history and physical examination, as well as limited diagnostic tests, point to a clear diagnosis in the majority of patients. Most often, conservative measures are effective. Steroid injections are often helpful for both diagnostic and therapeutic reasons. A small percentage of patients do not respond to conservative management and require operative intervention.     

Severe right ventricular contusion mimicking cardiac tamponade: the value of transesophageal echocardiography in blunt chest trauma

Clinically, severe right ventricular contusion may mimic cardiac tamponade. We report two cases of suspected cardiac tamponade after blunt chest trauma in which the diagnosis of severe right ventricular contusion was made only by transesophageal echocardiography, avoiding unnecessary and hazardous pericardiocentesis. These cases illustrate the value of transesophageal echocardiography in diagnosing blunt chest trauma.     

Intraoperative transesophageal echocardiography for detection of myocardial ischemia

Preoperative myocardial ischemia seems to be a predictor of poor outcome when detected by electrocardiography, pulmonary capillary wedge/pressure measurement and echocardiography. It could be demonstrated, that regional wall motion abnormalities appear earlier and are more sensitive signs of myocardial ischemia than the ECG. Using intraoperative epicardial and transesophageal echocardiography, high quality 2-d echocardiographic images of the heart can be recorded. For monitoring of left ventricular function and wall motion the transesophageal approach is most often used. By the transesophageal approach the left ventricle can be scanned in the long axis and by the transgastric approach in cross sections. They correspond to the apical four-chamber and left parasternal cross sectional imaging of the heart. Using the transgastric approach in the papillary short axis view all segments representing the three coronary arteries can be imaged. Recording in this position have been found to be highly reproducible. Only localized ischemia of the apex of the ventricle may be missed. Methologically the rotation and translocation of the heart remain a problem using the cross section images of the heart. But the left ventricular papillary muscles and the septal-right ventricular boarders can be used as land marks. Wall motion is scored in five grades. In addition to the semiquantitative analysis also a quantitative calculation using computers is possible. Using the midd papillary short axis view in nearly 120 intraoperative transesophageal echocardiograms since 1989 analysis of the systolic wall thickening was possible in 73% of the patients. According to the literature review 87% of the patients undergoing coronary bypass surgery or non-cardiac surgery have signs of preoperative ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)     

Chest trauma: the role of transesophageal echocardiography

Aortic and cardiac injury is commonly seen with severe chest trauma and contributes to the morbidity and mortality of automobile accidents. Transesophageal echocardiography is emerging as an important diagnostic tool for the evaluation of cardiovascular injury in the setting of acute chest trauma, and anesthesiologists should be familiar with the echocardiographic features of these traumatic lesions.     

Comparison of vena contracta width by multiplane transesophageal echocardiography with quantitative Doppler assessment of mitral regurgitation

OBJECTIVE: To compare prostacyclin with an analogue, iloprost, in treatment of severe pulmonary hypertension. PATIENTS: Eight patients with severe pulmonary hypertension: primary in five, thromboembolic pulmonary hypertension in three. METHODS: All patients underwent right heart catheterisation. Mean (SEM) right atrial pressure was 9.9 (2.2) mm Hg, mean pulmonary artery pressure 67.4 (3.0) mm Hg, cardiac index 1.75 (0.13) l/min/m2 and mixed venous oxygen saturation 59.1(3.1)%. Continuous intravenous epoprostenol (prostacyclin, PGI2) or iloprost was given for phase I (three to six weeks); the patients were then crossed over to receive the alternate drug in an equivalent phase II. MAIN OUTCOME MEASURES: Exercise tolerance was measured at baseline and at the end of phase I and II with a 12 minute walk; distance covered, rest period, percentage drop in arterial oxygen saturation (delta Sao2%) and percentage rise in heart rate (delta HR%). RESULTS: Walking distance covered rose from (mean (SEM)) 407.5 (73) to 591 (46) m with PGI2 (p = 0.004) and to 602.5 (60) m while on iloprost (p = 0.008). Rest period decreased from 192 (73) seconds at baseline to 16 (16) seconds with PGI2 (p = 0.01) and to 58 (34) seconds with iloprost (p = 0.008). Delta HR% was 37.5(6)% at baseline, 35(3)% on PGI2, and 24(6)% on iloprost (p = 0.04). CONCLUSIONS: Both intravenous PGI2 and iloprost caused significant improvement in exercise tolerance. Iloprost offers an alternative to PGI2 treatment of severe pulmonary hypertension.     

Who uses transesophageal echocardiography in the operating room?

A survey was made of 155 anesthesiology residency programs in the United States to determine the patterns of use, responsibility for interpretation, and training of those responsible for intraoperative transesophageal echocardiography (TEE). Survey questions included numbers and types of cases for which TEE is used, who interprets TEE data and how they are trained, the extent of resident training in TEE, and beliefs about the utility of TEE. One hundred eight completed surveys were returned (70% response). Of those responding, 98 (91%) use intraoperative TEE. In 53 of those 98 institutions (54%), an anesthesiologist was primarily responsible for the interpretation of TEE data, whereas a cardiologist was responsible in the remainder. Approximately 35% of anesthesiologists using TEE had training in its use during residency or fellowship; the remainder were trained after finishing residency or fellowship. Forty-two percent of anesthesiologists who use TEE leave a formal interpretation on the chart apart from the anesthesia record, and 43% bill specifically for performing TEE. Although 69% of those responding thought that formal credentials should be required for anesthesiologists to use intraoperative TEE, only 32% reported that their institutions actually mandated this. 38% of those responding stated that they offer a dedicated TEE rotation to their residents, and 13% thought that their graduating residents were trained well enough to use TEE on their own. Among academic institutions responding, the use of intraoperative TEE is nearly universal, responsibility for its interpretation is split almost evenly between cardiologists and anesthesiologists, and there is a disparity between opinions and reality with regard to TEE credentialing for anesthesiologists.