Intraoperative Transesophageal Echocardiography Monitoring Research Articles

Use of Transesophageal Echocardiography for Enhanced Safety During Bar Removal Procedures After Minimally Invasive Repair of Pectus Excavatum.

Background: Minimally invasive repair of pectus excavatum involves placement of retrosternal support (Nuss) bars. Hardware removal has been rarely associated with life-threatening hemorrhage from the heart, aorta, internal mammary arteries, and/or lung. There is no accepted standard intraoperative monitoring technique used during removal. We hypothesized that the use of transesophageal echocardiography (TEE) during Nuss bar removal would enhance safety of the procedure and be cost-effective. Methods: IRB-approved retrospective review of patients who underwent Nuss bar removal with intraoperative TEE monitoring over a 4-year period, from March 2013 to May 2017, was completed. Bar removal procedures were performed supine, under general anesthesia. TEE images were monitored and any distortion of the cardiac silhouette, new pericardial effusion, and/or cardiac arrhythmias would be considered evidence of possible bar adherence, triggering possible conversion to sternotomy or thoracotomy. Results: In total, 87 consecutive patients, mean age of 20 years, were identified. Bars had been in place for a mean of 30 months. Average procedure time was 67 minutes. No patients experienced arrhythmias, cardiac injury, or significant hemorrhage during removal. TEE gave excellent visualization of the cardiac silhouette and pericardium in all cases. No patient required insertion of an arterial line, a postoperative chest X-ray, or overnight hospitalization. Patients were discharged from the recovery room an average of 89 minutes postprocedure. Conclusion: TEE offers a minimally invasive safe way to visualize the pericardium and its contents during Nuss bar removal. Significant cardiac/mediastinal injuries should be immediately visible. The use of TEE is cost-effective and allows safe discharge the day of surgery.

Abstract P3012: Routine Monitoring For Intracardiac Thrombosis And Pulmonary Embolism With Intraoperative Transesophageal Echocardiography In Orthotopic Liver Transplantation

Background: Intracardiac thrombosis (ICT) and pulmonary embolism (PE) are significant intraoperative complications during orthotopic liver transplantation (OLT). Despite the high mortality associated with these events, current monitoring practices are inadequate at detecting these complications during OLT. Transesophageal echocardiography (TEE) allows continuous monitoring of myocardial function and detection of ICT/PE. In this study, we aim to report the incidence of ICT/PE during OLT at our center and to advocate for the use of intraoperative TEE as a standard monitoring tool. We also propose a medical management algorithm stratified by the severity of RV dysfunction and pulmonary artery pressure (PAP) in cases of ICT with/without PE. Methods: We conducted a single-center retrospective chart review of OLT patients with intraoperative TEE monitoring from March 13, 2019 - March 13, 2023. Intraoperative data of interest included hemodynamics, RV dysfunction, PAP, presence of ICT and/or PE as identified on TEE and associated medical management. RV dysfunction was graded as mild, moderate, or severe reduction in cardiac contractility. Secondary outcome was mortality during index hospitalization. Results: We identified 99 patients at our center who had intraoperative TEE monitoring during OLT. Prevalence of ICT in this population was 9.09% (n=9), of which 44.4% (n=4) developed hemodynamically significant PE. ICT patients who remained hemodynamically stable were observed without intervention (33%, n=3). Heparin was administered to prevent thrombus enlargement in patients with an increase in PAP but no significant RV dysfunction detected on TEE (22%, n=2). Those showing signs of hemodynamically significant PE with moderate or severe RV failure were given tissue plasminogen activator (tPA) for thrombolysis (44%, n=4). Perioperative mortality among all ICT patients was 44.4% (n=4) due to hemorrhagic shock secondary to coagulopathy and heart failure. Conclusion: The results of this study show the utility of routine TEE use in intraoperative monitoring for identifying ICT and PE in OLT patients, given the high mortality associated with these complications. TEE also allows for a stepwise approach to medical management based on RV function and PAP.

Intraoperative Transesophageal Echocardiography in Tricuspid Valve Surgery

Imaging the tricuspid valve (TV) using transesophageal echocardiography (TEE) seems more difficult than imaging other cardiac valves due to not only the complex valvular structure but also the anterior, far-field distance from the probe. The focus of the TEE during the surgery would not be much different from that of preoperative TEE. However, the anesthesia-induced changes of ventricular contractility, filling status, and vascular resistance should be considered when interpreting the images. Here, we thoroughly reviewed the major issues in the preand post-cardiopulmonary bypass intraoperative TEE in the TV surgery. Ultimately, a real-time intraoperative TEE monitoring should involve a simple or less time-consuming analysis which gives quick on-site information regarding the cardiac or hemodynamic status, communicating with the surgeon to lead to an optimal process. Keywords: Intraoperative; Echocardiography, Transesophageal; Tricuspid valve

Benefit of transesophageal echocardiography monitoring during cesarean section in a patient with complete atrioventricular canal defect

Anesthesia is a challenge in patients with congenital heart disease, especially during pregnancy and surgical delivery. A 23-year-old with a 34-week gestation, primigravida with atrioventricular (AV) canal defect was scheduled for a cesarean section. Preoperative transthoracic echocardiography (TTE) revealed a complete AV canal defect (Rastelli type II) with left-to-right shunt. Ventricular functions were normal. The patient was administered general anesthesia with endotracheal intubation, and a transesophageal echocardiography (TEE) probe was placed to monitor cardiac functions. The volume status of the parturient and the shunt fraction were continuously monitored with the echocardiography probe during the surgery. Minimal shunting at ventricular septal defect (VSD) was observed, as it was covered by the AV valve leaflets. The patient tolerated the procedure well and the trachea was extubated once she fulfilled the extubation criteria. Intraoperative TEE monitoring was a useful tool to understand and manage hemodynamic variations during cesarean section in the parturient with a complex cardiac lesion.

McGRATH MAC video laryngoscope for insertion of a transoesophageal echocardiography probe: A randomised controlled trial.

BACKGROUNDTransoesophageal echocardiography (TOE) probe insertion in anaesthetised patients can cause pharyngeal and oesophageal injuries. Kim et al. have shown that insertion assisted by a Macintosh laryngoscope can reduce such complications but it may sometimes be difficult to observe the passage of a TOE probe. The McGRATH MAC (McGRATH) has been shown to provide a better view of the glottis, piriform fossa and oesophageal inlet during tracheal intubation than the Macintosh.OBJECTIVEWe hypothesised that the McGRATH provided better visualisation of the oesophageal inlet and was useful as an aid to TOE probe placement, possibly reducing the incidence of pharyngeal injury related to insertion, compared with the Macintosh.DESIGNA randomised controlled trial.SETTINGThe study was conducted in a university hospital from February to December 2014.PATIENTSOne hundred patients undergoing elective surgery under intraoperative TOE monitoring were randomised to either a Macintosh group or a McGRATH group.INTERVENTIONSMacintosh and McGRATH were used to visualise the passage of the TOE probe and guide its insertion.MAIN OUTCOME MEASURESVisibility of the oesophageal inlet, the number of TOE insertion attempts and incidence of pharyngeal mucosal injury after the TOE probe had been removed were assessed.RESULTSThe percentage of patients in whom the oesophageal inlet was visible was higher in the McGRATH group (88%) than in the Macintosh group (41%) (P < 0.01). The number of TOE probe insertion attempts was significantly smaller in the McGRATH group than in the Macintosh group (P = 0.039). The incidence of pharyngeal mucosal injury was significantly smaller in the McGRATH group (4%) than in the Macintosh group (16%; P = 0.042).CONCLUSIONThe McGRATH provided a better view of the oesophageal inlet and was useful as an aid to TOE probe placement, possibly reducing the incidence of pharyngeal injury related to its insertion.TRIAL REGISTRATIONUniversity Hospital Medical Information Network in Japan (UMIN) 000012970.

Clinical research on the application of trans-esophageal echocardiography in monitoring Nuss surgery

To investigate the validity and safety of trans-esophageal echocardiography (TEE) in monitoring of Nuss surgery. A total of 140 patients with pectus excavatum from Sichuan Provincial People's Hospital underwent Nuss surgery from August, 2011 to Aμgust, 2013. Among them, 72 patients received TEE monitoring while 68 patients didn't. The injury of heart and large vessels by the introducer and Nuss steel bar was observed by intraoperative TEE monitoring under middle-esophageal four chamber view and middle-esophageal aortic short axis view. The operation in all patients had been performed successfully without any severe complications. Satisfactory TEE images were obtained in all patients. The procedure of inserting the inducer and Nuss steel bar behind sternum and steel bar overturn could be seen clearly. No injury in heart and large vessels was detected. Local streak-like hemorrhage in 3 patients was observed under intra-operative TEE screen, but no further new bleeding was found in postoperative TEE examination. The blood was absorbed and couldn't see under trans-thoracic echocardiography in 1 month after the operation. The TEE is a non-invasive monitoring method. It is sensitive to detect the status of the heart and large vessels and can prevent the severe complications due to Nuss surgery.

Transesophageal Echocardiography During Orthotopic Liver Transplantation in Patients with Esophago-Gastric Varices

Background: Hemodynamic monitoring using transesophageal echocardiography (TEE) in patients with signs of portal hypertension undergoing orthotopic liver transplantation (OLT) carries potential risk of esophageal and gastric variceal hemorrhage. The aim of our retrospective analysis was to evaluate the safety of intraoperative TEE monitoring during OLT in patients with esophago-gastric varices. Patients and methods: Retrospective analysis of 396 liver transplant recipients at the Medical University of Vienna monitored by TEE during OLT between 2003 and 2010. Results: Varices were documented by esophagogastroduodenoscopy in 287 (72.5 %) of 396 analyzed patients: 130 (32.8 %) varices grade I (< 5mm under insufflation) and 157 (39.6 %) varices grade II (> 5mm under insufflation). Red spot signs were identified in 40 patients (10.1 %). The majority of varices (82.2 %) were documented in the esophagus, 4.2 % in the stomach and 13.6 % in both (esophagus and stomach). In only one case of one patient with an esophageal varix one major bleeding occurred and was treated with balloon tamponade during OLT. Although patients with varices had a significantly longer prothrombin time and lower platelet count, there was no significant difference in the requirement for blood products among patients with and without varices. Conclusions: TEE is a relatively safe method for monitoring of cardiac performance with a low incidence of major hemorrhagic complications in patients with documented esophago-gastric varices undergoing OLT.

Transesophageal Echocardiography During Orthotopic Liver Transplantation in Patients With Esophagoastric Varices

Hemodynamic monitoring using transesophageal echocardiography (TEE) in patients with signs of portal hypertension undergoing orthotopic liver transplantation (OLT) carries potential risk of esophageal and gastric variceal hemorrhage. The aim of our retrospective analysis was to evaluate the safety of intraoperative TEE monitoring during OLT in patients with esophagogastric varices. A retrospective analysis of 396 liver transplant recipients was performed at the Medical University of Vienna monitored by TEE during OLT between 2003 and 2010. Varices were documented by esophagogastroduodenoscopy in 287 (72.5%) of 396 analyzed patients: 130 (32.8%) varices grade I (<5 mm under insufflation) and 157 (39.6%) varices grade II (>5 mm under insufflation). Red spot signs were identified in 40 patients (10.1%). Most varices (82.2%) were documented in the esophagus, 4.2% in the stomach, and 13.6% in both (esophagus and stomach). Only one major bleeding occurred, and it was only in a case of one patient with an esophageal varix, which was treated with a balloon tamponade during OLT. Although patients with varices demonstrated a significantly longer prothrombin time and lower platelet count, there was no significant difference in the requirement for blood products among patients with and without varices. TEE is a relatively safe method for monitoring cardiac performance with a low incidence of major hemorrhagic complications in patients with documented esophagogastric varices undergoing OLT.

TEVAR for Ruptured Mycotic Aneurysm in a Patient With a Left Ventricular Assist Device

To report endovascular treatment of a ruptured mycotic aneurysm in a patient with previous cardiac surgery, a cardioverter-defibrillator, and an intrathoracic left ventricular assist device (LVAD). A 75-year-old man was admitted for a syncopal episode and severe back pain. The patient had a past history of postischemic dilatative cardiomyopathy for which a cardioverter-defibrillator was implanted. An LVAD and bioprosthetic aortic valve were subsequently placed due to severe cardiogenic shock. The postoperative course was complicated by methicillin-resistant Staphylococcus aureus mediastinitis and acute renal failure requiring temporary dialysis. At the current admission 4 months later, urgent computed tomography (CT) showed a ruptured aneurysm in the middle third of the descending thoracic aorta; blood cultures were positive for Candida sp . The patient was hemodynamically stable, so he was placed in intensive care and given targeted antimicrobial therapy while an endovascular treatment was planned. At surgery, a rifampicin-soaked Relay Plus 30-mm×95-cm stent-graft was deployed through a right common femoral cutdown to seal the aortic rupture. Successful aneurysm exclusion was confirmed by intraoperative transesophageal echocardiography (TEE). At the 6-month follow-up, the patient was without recurrent pathology or graft infection as demonstrated by CT. Thoracic endovascular aortic repair in patients with LVAD is peculiar for several aspects: accurate planning is necessary to adequately visualize the aortic lesion despite the presence of many radiopaque devices and the femoral arteries are pulseless. Moreover, extremely slow washout of contrast from the aortic rupture prevents correct assessment of final sac exclusion with angiography; intraoperative TEE monitoring proved extremely useful.

Cost-effectiveness of intraoperative transesophageal echocardiography in cardiac valve surgery.

Being a unique diagnostic technique, transesophageal echocardiography (TEE) has influenced many different aspects of cardiac surgery including valve repair surgery. The cost-effectiveness of this method however is questioned considering the conditions of every region and country. In this study we aimed at answering the question if utilizing TEE throughout valve repair surgery could be cost-effective. Twenty four patients were studied within two groups of case "valve repair operation plus intra-operative TEE (IO-TEE)" and control "valve replacement operation". Variables including age, gender, left ventricle ejection fraction (LVEF), re-operation, intensive care unit (ICU) stay, hospital stay and cost were studied and compared. There was no significant difference regarding age, gender and LVEF between two groups (p=0.559, p=0.413, and p=0.408, respectively). ICU stay in repair group was less than replacement group (p=0.009). Hospital stay difference however was not statistically significant (p=0.928). The cost of valve repair under IO-TEE monitoring was significantly less than valve replacement (p=0.001). IO-TEE not only would assist surgeons by increasing their interest toward valve repair operation instead of replacing impaired cardiac valves but also consequently decrease hospital costs. It is also advised for the cardiac anesthesiologists to use IO-TEE routinely in the valve repair operations provided that there are no contraindications.

Incidental intracardiac thromboemboli during liver transplantation: Incidence, risk factors, and management

Even though numerous cases of massive thromboemboli have been reported in the literature, intracardiac thromboemboli (ICTs) incidentally found during orthotopic liver transplantation (OLT) have not been examined. In this study, we retrospectively examined the incidence, risk factors, and management of incidental ICTs during OLT. After institutional review board approval, adult patients who underwent OLT between January 2004 and December 2008 at our center were reviewed. ICTs were identified and confirmed by the examination of OLT datasheets, anesthesia records, and recorded transesophageal echocardiography (TEE) clips. The clinical presentation, management, and outcomes of the patients with ICTs were reviewed. Risk factors were analyzed by multivariate logistic regression. During the study period, 426 of the 936 adult OLT patients (45.5%) underwent intraoperative TEE monitoring. Incidental ICTs were identified in 8 of these 426 patients (1.9%). Two ICTs occurred before reperfusion, and 6 ICTs occurred after reperfusion. The treatment was at the discretion of the treating physicians; however, none of the patients received an anticoagulant or thrombolytics. Multivariate analysis identified 2 independent risk factors for intraoperative incidental ICTs: the presence of symptomatic or surgically treated portal hypertension (a history of gastrointestinal bleeding, a transjugular intrahepatic portosystemic shunt procedure, or portocaval shunt surgery) before OLT and intraoperative hemodialysis (odds ratios of 4.05 and 7.29, respectively; P < 0.05 for both). In conclusion, incidental ICTs during OLT occurred at a rate of 1.9% and were associated with several preoperative and intraoperative risk factors. The use of TEE allows early identification, which may be important. Our management for incidental ICTs is described; however, no conclusions can be made about the optimal therapy.

Impact of intraoperative transesophageal echocardiography in cardiac and thoracic aortic surgery: Experience in 1011 cases

Although intraoperative transesophageal echocardiography (IOTEE) has been widely used in cardiovascular surgery, the exact incidence of abnormalities detected by IOTEE in each type of surgical procedure is still unclear. The aim of this study was to review our experiences of IOTEE, in patients who underwent different types of cardiovascular surgery and to evaluate the clinical usefulness of IOTEE. Our database of 1011 consecutive patients, who underwent cardiovascular surgery and IOTEE monitoring was reviewed. The incidence of abnormal findings was 115 of 1011 patients (11.4%), and the highest incidence was the appearance of new wall motion abnormalities after cardiopulmonary bypass. These findings influenced surgical decision-making in 59 of the evaluated 1011 patients (5.8%). IOTEE provides important intraoperative and postoperative information that may influence surgical decision-making in various cardiovascular surgeries.

Three-dimensional Transesophageal Echocardiography for Mitral Valve Repair Surgery - A case report -

Although several reports have showed the application of 3-dimensional (3D) echocardiography, it is hard to find a report regarding the intraoperative use of real time 3D transesophageal echocardiography (TEE) in mitral valve repair surgery. In the present case, real time 3D TEE the one from the one TEE probe position as well as their rotated and cropped images showed detailed spatial images enough for immediate assessment of the mitral valve deformity and the characteristics of mitral regurgitation flow. Under cardiopulmonary bypass (CPB) employing moderate hypothermia, the prolapsed mital leaflet was excised, the ruptured cord was repaired and an annuloplasty ring was inserted to reinforce the mitral valve and to close up the defect. The 2D and 3D TEE images after CPB showed effective repair providing complete closure of the mitral leaflets and absence of residual regurgitation flow. Considering that the conventional 2D TEE requires examiner's ability to gather the various 2D TEE images and experience essential for intergrating the 2D images for full understanding of spatial structure of valvular deformity and dysfunction, 3D TEE's ability for making a comprehensive spatial image from a limited number of 2D images seems to have an additional clinical efficacy in intraoperative TEE monitoring for cardiac value surgery. (Korean J Anesthesiol 2008; 54: 685~8)

The safe use of intraoperative transesophageal echocardiography in the management of total anomalous pulmonary venous connection in newborns and infants: a case series

Intraoperative transesophageal echocardiography (TEE) is useful in evaluating the repair of lesions in patients with congenital heart disease. But the use of TEE in infants with total anomalous pulmonary venous connection (TAPVC) remains unclear. We reviewed the safety and efficacy of intraoperative TEE during TAPVC repair. Twenty-eight consecutive 1 day to 7 month-old infants with TAPVC (14 supracardiac, six intracardiac and eight infracardiac type) had surgical repair with intraoperative TEE monitoring. Four patients received immediate surgical revision after primary surgery for residual anastomotic stenosis diagnosed by TEE. In addition, two unsuspected ventricular septal defects and three persistent ductus arteriosus were detected before surgery. Eight infants (29%) had hypotension and hypoxemia associated with TEE probe insertion before surgery, but this hemodynamic disturbance returned to baseline value after withdrawing the TEE probe from the esophagus. However, these eight patients had uneventful TEE probe insertion following sternotomy. The mechanism was probably because of the reduction of intrathoracic pressure when the chest was opened. TEE probe insertion in TAPVC patients may pose a potential risk of compression of pulmonary venous confluence resulting in hemodynamic instability. Therefore, we suggest that the use of TEE in such TAPVC patients appears to be safer after sternotomy.

Intraoperative Myocardial Ischemia Recognized by Transesophageal Echocardiography Monitoring in the Pediatric Population: A Report of 3 Cases

We used continuous intraoperative transesophageal echocardiography (TEE) monitoring to detect intraoperative myocardial ischemia in children after they had been weaned from cardiopulmonary bypass for cardiac surgery. Three pediatric patients are described here to illustrate the usefulness of such TEE monitoring in surgical procedures involving coronary arteries. The indications for intraoperative TEE monitoring and a simplified scheme for immediate qualitative interpretation are discussed. (J Am Soc Echocardiogr 2000;13:615-8.)

Recurrent laryngeal nerve palsy after cardiovascular surgery: Relationship to the placement of a transesophageal echocardiographic probe

Objective: To examine the relationship between the incidence of recurrent laryngeal nerve palsy after cardiovascular surgery and the placement of a transesophageal echocardiographic probe. Design: A prospective clinical study. Setting: A single-institutional study in a university hospital. Participants: One hundred sixteen patients undergoing cardiovascular surgery. Interventions: All patients were assigned into one of two groups: 64 patients in whom transesophageal echocardiography (TEE) was performed and 52 patients in whom TEE was not performed during surgery. The incidence of recurrent laryngeal nerve palsy was examined and compared between the two groups. Measurements and Main Results: Five of 64 patients (7.8%) in whom TEE was monitored and 3 of 52 patients (5.8%) in whom TEE was not monitored were diagnosed with recurrent laryngeal nerve palsy postoperatively. There was no statistically significant difference between the incidence of recurrent laryngeal nerve palsy in patients with intraoperative TEE monitoring, and patients without it. The durations of surgery, anesthesia, and cardiopulmonary bypass were significantly longer in patients with nerve palsy than those without it. Conclusion: These results suggest that placement of the transesophageal echocardiographic probe is not responsible for postoperative recurrent laryngeal nerve palsy. It seems likely that surgical manipulation itself and the durations of surgery, cardiopulmonary bypass, and tracheal intubation are related to the incidence of laryngeal nerve palsy.

Transesophageal echocardiography and orthotopic liver transplantation: general concepts.

T ransthoracic echocardiography is used extensively in the preoperative evaluation of patients undergoing liver transplantation and provides information about global cardiac function, valvular function, and presence of pericardial effusion. Dobutamine stress echocardiography and contrast-enhanced echocardiography are evolving into essential tools in the screening and/or evaluation of patients with possible coronary artery disease,1,2 pulmonary hypertension, or hepatopulmonary syndrome. Because of the potential for damage to esophageal varices with subsequent severe bleeding, transesophageal echocardiography (TEE) initially was used very reluctantly, but luckily this complication seems to be very uncommon, and, if it occurs, it is mild and self-limiting. Today, TEE is used more commonly in patients undergoing liver transplantation and has been helpful in the diagnosis and management of many conditions and complications.3 Patients with severe liver disease have a hyperdynamic hemodynamic system; most anesthesiologists believe high cardiac output has to be maintained perioperatively to maintain adequate perfusion of the tissues in the presence of peripheral shunting. Maintaining this high cardiac output can only be accomplished by maintaining preload. However, liver transplantation is associated with major changes in cardiac preload and afterload. Blood loss can be very significant, requiring the infusion of large amounts of fluids and blood products, potentially resulting in citrate toxicity. Graft reperfusion may lead to severe hypotension, usually the result of dramatic vasodilation, but in some patients, contractility changes are suspected to occur.4-6 Echogenic contrast material is seen entering the heart from the inferior vena cava on reperfusion in every patient,4 but clinically significant air embolism after reperfusion is uncommon. Although the interpretation of TEE remains mostly subjective, TEE has been helpful by providing additional information regarding preload and contractility. Filling pressures are not always reflective of preload because of significant changes in compliance.7 TEE may also help in the identification of the exact hemodynamic changes during postreperfusion syndrome.8,9 In addition, TEE has been used in the diagnosis and management of intraoperative complications, such as air embolism,10 thromboembolism,4,11,12 and the management of patients with unrelated cardiopulmonary disease, such as coronary artery disease, valvular pathological states, or idiopathic hypertrophic subaortic stenosis.13-15 Other patients with alcoholinduced cardiomyopathy, hemochromatosis, amyloidosis, or Wilson’s disease may benefit from intraoperative TEE monitoring. Pulmonary hypertension occurs more frequently in patients with severe liver disease; if it is decided to proceed with liver transplantation, TEE has proven to be an essential monitoring tool.16,17 TEE also allows the intraoperative diagnosis of hepatopulmonary syndrome in patients in whom the diagnosis was missed preoperatively.18-21 TEE has shown the presence of direct communications between portal vein and pulmonary veins.22 Finally, TEE allows for the intraoperative evaluation of the major vessels, including the suprahepatic inferior vena cava anastomosis; patients with previous LeVeen shunts may have narrowing or occlusion of the superior vena cava.23,24

Detection of aortic emboli by transesophageal echocardiography during coronary artery bypass surgery

The purpose of this study was to determine whether emboli can be detected within the aortic lumen in patients undergoing coronary artery bypass surgery (CABG) and to relate the appearance of emboli to specific operative events. Twenty patients were prospectively studied intra-operatively. Subjects were inpatients in an academic medical center. All participants were scheduled for elective, isolated CABG. Patients were continuously monitored using transesophageal echocardiography (TEE) from aortic cannulation to bypass discontinuation. After completion of the aortic examination, the probe was focused at the level of the aortic arch, just before the takeoff of the left subclavian artery. Emboli were defined as echogenic intraluminal signals not present in the same position on consecutive cross-sectional frames. Intraluminal emboli were detected in all subjects, with a mean number of 535 and range of 8 to 1,885. Embolization was unevenly distributed through the procedure. A mean of 224 (42%) of 535 were detected within 4 minutes of aortic cross-clamp release and another 140 (24%) appeared after partial occlusion clamp release. Together, clamp placement and release represented 84% of all emboli. Emboli detected after clamp release were large, echodense particles easily distinguishable from the small, indistinct, poorly echogenic signals observed at bypass initiation. Emboli can be visualized within the aortic lumen during CABG. Confirming previous reports, the majority of emboli detected are related to manipulation of aortic clamps. The composition and clinical significance of embolic material are unclear. The value of intraoperative TEE monitoring in predicting neurologic outcome remains to be determined.

Detection of residual flow by transesophageal echocardiography during video-assisted thoracoscopic patent ductus arteriosus interruption.

The purpose of this study is to examine prospectively the efficacy of intraoperative transesophageal echocardiography (TEE) monitoring in reducing the incidence of residual ductal flow during video-assisted thoracoscopic (VATS) patent ductus arteriosus (PDA) interruption. Thirty consecutive patients undergoing PDA interruption via the VATS procedure were monitored with an appropriately sized Hewlett-Packard color-Doppler TEE probe. All examinations were performed by the same individual and interpreted with a cardiologist. Real time TEE monitoring was used, but the results were not disclosed to the surgeon until he was prepared to close the wound. The mean age was 2.4 yr and the average weight 11.2 kg. Two patients had residual flow after placement of the vascular clip. One patient had residual flow detected intraoperatively after placement of the vascular clip and residual flow was quickly abolished by the placement of a second clip, thus avoiding a reintervention. A follow-up transthoracic echocardiography was performed on 18 patients 1 mo postoperatively. Three patients presented residual ductal flow. This study using a novel application of TEE, demonstrates that TEE monitoring during PDA interruption may improve the surgical result, thus avoiding reintervention and the complications associated with residual ductal flow. However, late recurrence due to recanalization may occur and may not be detected by intraoperative TEE monitoring.

Transesophageal echocardiographic monitoring during coronary artery bypass surgery.

To demonstrate serial changes of left ventricular (LV) function during coronary artery bypass grafting surgery, transesophageal echocardiography (TEE) was used in 17 patients. The cross-sectional image of the left ventricle at the level of the papillary muscles was monitored, and was analyzed immediately in the operating room using a computer-assisted cine-memory function. Global LV function was evaluated by measuring LV end-diastolic and end-systolic area and computing the fractional area change (FAC). Segmental wall motion abnormalities (SWMA) were graded according to a scoring system. During the operative procedure before sternal closure, 5 patients showed SWMA with a simultaneous decrease in FAC to under 40%, and 9 patients showed SWMA without FAC depression. Two-thirds of new SWMA improved after myocardial revascularization. All 17 patients showed a change of interventricular septal movement at the end of the operation. FAC improved from a mean value (+/- SD) after intubation of 47.6 +/- 10.7% to a mean value after revascularization of 58.5 +/- 13.0% (p less than 0.05) and to a mean value at the end of the operation of 55.9 +/- 12.2% (p less than 0.05). Thus: 1) global and regional LV function improved immediately after myocardial revascularization with administration of inotropic agents; 2) a significant change of interventricular septal movement occurred after sternal closure; and 3) intraoperative TEE monitoring is a safe, simple, and effective method for evaluating LV global and regional function.