Transoesophageal echocardiography in cardiac anaesthesia

Echocardiography is the most widely used minimally invasive investigation to diagnose heart disease. Transoesophageal echocardiography (TOE) was first introduced perioperatively in the 1980s and is now an important monitoring tool for patients undergoing cardiac surgery. Because of the close proximity of the oesophagus to the heart, TOE facilitates the acquisition of high-resolution images. The TOE probe is a multiplane transducer. This means that the image planes can be rotated from 0° to 180°, enabling three-dimensional (3D) assessment of the structure of interest. Intraoperative TOE has been shown to improve outcome in a variety of cardiac surgeries. The introduction of real-time 3D TOE has provided better diagnosis of the mechanism of certain valve pathologies. TOE has become an important investigation in the assessment of haemodynamic instability in the perioperative period because it allows rapid and accurate diagnosis.     

Transoesophageal echocardiography in cardiac anaesthesia

Echocardiography is the most widely used minimally invasive investigation to diagnose heart disease. Transoesophageal echocardiography (TOE) was first introduced perioperatively in the 1980s and is now an important monitoring tool for patients undergoing cardiac surgery. Because of the close proximity of the oesophagus to the heart, TOE facilitates the acquisition of high-resolution images. The TOE probe is a multiplane transducer. This means that the image planes can be rotated from 0° to 180°, enabling three-dimensional (3D) assessment of the structure of interest. Intraoperative TOE has been shown to improve outcome in a variety of cardiac surgeries. The introduction of real-time 3D TOE has provided better diagnosis of the mechanism of certain valve pathologies. TOE has become an important investigation in the assessment of haemodynamic instability in the perioperative period because it allows rapid and accurate diagnosis.     

Transoesophageal echocardiography in cardiac and vascular surgery: implications and observer variability

Transoesophageal echocardiography (TOE) has gained widespreadacceptance among cardiac anaesthetists as a tool to facilitateperi-operative decision-making. This observational study analysesthe impact of TOE and its inter-observer variability on intra-operativepatient management during cardiac and major vascular surgery.From June 1996 to December 1998, standardized reports were obtainedfrom 11 anaesthetists in 1891 adult cardiac and vascular surgerypatients undergoing routine biplane or multiplane TOE. Inter-observervariability and the difference between variables of interestwere tested using the chi-squared test or factorial analysisof variance as appropriate. TOE examinations were performedbefore and after the operation; 1673 (88.5%) patients underwentcardiopulmonary bypass (CPB), and 218 (11.5%) patients had surgerywithout CPB, including 42 (2.2%) coronary revascularizations.In 923 patients (49%), TOE provided additional information thatinfluenced the patient’s therapy. In 968 patients (51%),TOE had only minor or no impact on clinical decision-making.In two patients (0.10%) the scheduled operation was not performed,and in another two patients the TOE examination led to majorcomplications. Observer-dependent variables were: implicationsof TOE for intra-operative decision-making (P<0.0001), estimationof image quality (P<0.0001), pre-operative left ventricularfractional area change (FAC) (P=0.0026), difference betweenpre-operative FAC and post-operative FAC (P=0.033), and requestsfor supervision (P<0.0001). There was no significant differencein the case mix between observers. TOE had an important impacton intra-operative patient management. Inter-observer variabilitywas significant for several variables but not for the frequencyof additional surgical procedures. Br J Anaesth 2001; 86: 497–505     

Transoesophageal echocardiography for the detection and quantification of pleural fluid in cardiac surgical patients

Background: Transoesophageal echocardiography (TOE) can image pleural fluid.Left pleural collections may be easier to detect than right,as the thoracic aorta serves as an acoustic window. Attemptsto quantify pleural fluid using TOE are restricted to a casereport in which volume was predicted by multiplying maximalcross-sectional area (CSA_max) by axial length (AL). A computedtomography (CT) derived formula for quantifying pleural effusionsis maximal effusion depth squared (d²) multiplied by maximaleffusion length. Methods: Eight patients were studied before chest closure following coronarybypass surgery. Fifty millilitre saline aliquots were instilledinto the pleural space until detected by TOE. Saline was theninstilled up to the next 200 ml increment and further 200 mlaliquots added until it spilled from the pleural space. CSA_max,d and AL were measured for each stage and used to calculatepleural fluid volume. Results: Median detection volume (range) was 125 ml (50–200) onthe left and 225 ml (150–300) on the right (P = 0.016).Volume calculated by CSA_max x AL correlated strongly with actualvolume (r² = 0.93 left and 0.92 right) as did volume calculatedby d² x AL (r² = 0.86 left and 0.89 right). Mean differencebetween volume calculated by CSA_max x AL and actual volume was– 51 ml on the left and 45 ml on the right vs –253 ml on the left and – 212 ml on the right for volumecalculated by d² x AL. Conclusions: TOE detects small volumes of pleural fluid on both sides ofthe chest. CSA_max x AL provides a reasonably accurate measureof pleural fluid volume.     

Transoesophageal echocardiography (TOE) in the operating room

Perioperative transoesophageal echocardiography (TOE) was introducedfrom cardiology into cardiac anaesthesia in the 1980s. InitiallyTOE was used mainly as a monitor of left ventricular ischaemia,but now provides real-time dynamic information about the anatomyand physiology of the whole heart. TOE is of value in the managementof patients undergoing procedures including cardiac valvularrepair, surgery for endocarditis, surgery of the thoracic aorta,and may contribute useful information in a wide range of cardiacpathology. It is also useful in guiding therapy in haemodynamicallyunstable patients in the operating room and the intensive careunit. TOE is relatively cheap and non-invasive, but it shouldnot be used as a stand alone device but as a tool which providesdata in addition to the data acquired from other forms of monitoring.The use of TOE carries not only the benefits of a rapid andeffective investigation, but also risks associated with theprocedure itself and the burden of providing training and experiencefor practitioners. The establishment of TOE in perioperativecardiac anaesthetic care has resulted in a significant changein the role of the anaesthetist who, using TOE, can providenew information which may change the course and the outcomeof surgical procedures.     

Transoesophageal echocardiography in the critically ill

Echocardiography offers real-time bedside diagnosis and monitoring of a variety of structural and functional abnormalities of the heart. Transoesophageal echocardiography, in particular, provides information on cardiac contractility, filling status and output, valvular morphology and function and on the structure of the ascending and descending aorta in the critically ill patient. The full range of modalities of echocardiography, including M-mode, 2-D-mode, colour Doppler and spectral Doppler, is at the disposal of the intensive care specialist. In this review, the indications for and the clinical impact of transoesophageal echocardiography and Doppler are discussed.     

Effective systolic orifice area of the aortic valve: implications for Doppler echocardiographic cardiac output determinations

BACKGROUND: Substantial research using echocardiography has established that stroke volume (SV) or cardiac output (CO) can be measured non-invasively at the level of the aortic valve (AV) with high accuracy. Stroke volume is the product of the velocity time integral occurring at the sampling site and the effective systolic AV orifice area (AVOAeff). Nevertheless, a generally accepted method for the determination of AVOAeff is still lacking. METHODS: Aortic valve OAeff was measured in 228 consecutive patients scheduled for coronary artery surgery. Two widely adopted methods were applied to approximate the constantly changing orifice area of the AV: (1) the circular orifice model (AVOA-CM), and (2) the triangular orifice model (AVOA-TM). Aortic valve OA-CM assumes the shape of a circle as an appropriately time averaged geometrical model, and AVOA-TM takes the shape of an equilateral triangle for granted. RESULTS: The AV was easily imaged by echocardiography in both short- and long-axis views in all patients. Relying on AVOA-CM, AVOAeff was 3.49+/-0.77 cm2. AVOA-TM estimates were 2.80+/-0.55 cm2 (mean+/-SD). The results did not agree (bias analysis). CONCLUSIONS: The echocardiographic measurement of SV or CO at the level of the AV has to be reconsidered.     

Transoesophageal echocardiography in cardiac anaesthesia

Echocardiography is the most widely used minimally invasive investigation to diagnose heart disease. Transoesophageal echocardiography (TOE) was first introduced perioperatively in the 1980s and is now an important monitoring tool for patients undergoing cardiac surgery. Because of the close proximity of the oesophagus to the heart, TOE facilitates the acquisition of high-resolution images. The TOE probe is a multiplane transducer. This means that the image planes can be rotated from 0° to 180°, enabling three-dimensional assessment of the structure of interest. Intraoperative TOE has been shown to improve outcome in mitral valve surgery and is frequently used by the surgeon as an aid in deciding whether to repair or replace the valve. TOE has become an important investigation in the assessment of haemodynamic instability in the perioperative period because it allows rapid and accurate diagnosis.     

Transoesophageal echocardiography is unreliable for cardiac output assessment after cardiac surgery compared with thermodilution

This randomised, single-blind, double-control study compared and established prospectively the best transoesophageal echocardiography methods for determining cardiac output in patients after cardiac surgery. Thirty patients undergoing coronary artery bypass grafting were included. Measurements were taken postoperatively, after stabilisation in the intensive care unit. Cardiac output was determined by transoesophageal echocardiography in randomised order through the aortic, mitral, and pulmonary valves, right and left ventricular outflow tracts, transgastric surface areas of the left ventricle and left ventricle two-dimensional volumes (Simpson's rules). 'Eyeball guessing' was done off-line. The best results were transaortic measurements using the triangular shape assumption of valve opening, but some values deviated considerably, and none of these approaches reached the limit of agreement set at 30% when compared to thermodilution. Eyeball guessing was comparable to the best transoesophageal echocardiography measurements. We conclude that transoesophageal echocardiography is an unreliable tool for determination of cardiac output in intensive care after cardiac surgery.     

Real time 3-D echocardiography in cardiac surgery

Objective: Real time 3-D echocardiography provides real time live images of intracardiac anatomy. We evaluate its clinical application for intraoperative echocardiography. Method: The “xStream“3-D architecture designed with “xMatrix array“ using approximately 3,000 transducer elements achieves live digital volume imaging in real time 3-D echocardiography (SONOS 7500, Philips Medical Systems, Inc.). Intraoperative echocardiography was performed in mitral (n=14) and aortic valve diseases (n= 6), 4 heart anomaly, 4 aortic diseases and 15 normal anatomies. Results: Heart valves were depicted via enface view. Simultaneous movement of leaflets and subvalvular apparatus can be observed. Prolapsed leaflets are easily detected and regurgitated jets are detected as 3-D color images. The four cardiac chambers were observed in their real shape and size. Septum defects were also depicted in real shape, size and position. Precise intracardiac anatomy was observed in cardiac anomalies. Information on the endothelium, intimal flap, entry, reentry and aortic wall character was provided and allowed for planning in aortic surgery. Conclusion: Live 3-D echocardiography provides excellent depiction of any cardiac and aortic anatomy in any direction and greatly enhances efficiencies in planning appropriate surgical procedures. Read at the Fifty-sixth Annual Meeting of the Japanese Association for Thoracic Surgery, Symposium, Tokyo, November 19–21, 2003.     

Transoesophageal echocardiography in cardiac anaesthesia and intensive care

Transoesophageal echocardiography (TOE) is being increasingly used throughout the field of anaesthesia and intensive care and nowhere has its impact been greater than in cardiac practice. This article outlines the main uses for TOE in current practice and explores the different ways in which it may affect anaesthetic and surgical management. Use of TOE for diagnostic purposes includes the assessment of valvular and other pathologies as well as for the rapid diagnosis of acute hypotension. Its use as a monitor for ischaemia and haemodynamic disturbances is also discussed. The importance of training and quality assurance are examined from a user's perspective and lastly a glimpse into the future reveals the enticing prospect of real-time 3 dimensional cardiac imaging.     

经食管超声心动图在机器人心脏手术中的应用

目的探讨经食管超声心动图(transesophageal echocardiography,TEE)在机器人体外循环心脏手术中的应用价值。 方法对110例心脏病患者在机器人体外循环术中行TEE检查,体外循环转机前评估心脏病变,验证经胸超声心动图(transthoracic echocardiography,TTE)结果,根据结果协助手术医师进一步确定手术方案。建议外周体外循环过程中,TEE引导下腔静脉插管(经股静脉)、上腔静脉插管(经右侧颈内静脉)。心脏复搏后,TEE评估手术疗效、手术并发症、排气情况。将其结果进行回顾性分析。 结果本组患者全在机器人下完成手术,其中2例中转右前外侧切口。体外循环转机前TEE诊断与TTE结果有7例不相符,经术中证实TEE准确性100%。TEE引导所有下、上腔静脉插管成功,成功率100%,体外循环过程中无静脉引流不畅。心脏复搏后2例室间隔缺损有残余分流、1例二尖瓣成形后仍有中度反流、1例主动脉瓣置换术后瓣周漏,经再次阻断处理后均取得满意效果。其余患者手术疗效确切,术后再次TTE证实无手术相关并发症。 结论TEE在机器人体外循环术中能提高手术成功率及安全性,是有效的术中诊断手段。     

Transoesophageal echocardiographic monitoring during paediatric cardiac surgery: obtainable information and feasibility in 532 children

BACKGROUND: We hypothesized that transoesophageal echocardiography (TOE) performed by the anaesthesiologists would be beneficial for monitoring purposes during paediatric cardiac surgery. We present the results for the first 5 years in 532 consecutive children. METHODS: The probe was successfully inserted in 99% of cases and remained in the oesophagus for 211 min on average (range 10-555 min). RESULTS: Insignificant valve leak, single- or biventricular failure and volume depletion were the most common new findings due to TOE. Changes in inotropic strategy and volume replacement were the most frequent interventions. In 45% of the cases, new information was disclosed and, in a total of 8% of cases, decisive information was provided. Except for tracheal extubation in one child who was uneventfully reintubated, no severe complications were identified. CONCLUSIONS: These data stress the safety and ease of performing TOE in children undergoing cardiac surgery. There is evidence for benefit from TOE findings to potentially enhance the therapeutic basis.     

Ross手术的临床应用

目的　报告 6例Ross手术的临床经验和手术结果。方法　自 1998年 3月至 1999年 10月 ,6例主动脉瓣瓣膜疾病病人中男 3例 ,女 3例 ;年龄 4～ 38岁 ,平均 (14± 12 )岁。诊断为主动脉瓣二瓣化畸形伴狭窄 3例 ,其中 1例伴有室间隔缺损 ;主动脉瓣脱垂 2例 ;单纯主动脉瓣狭窄 1例。均接受了Ross手术。结果　无手术死亡 ,全部治愈出院 ,随访效果满意。结论　Ross手术安全、效果好 ,可适于某些主动脉瓣瓣膜病变 ,尤其适合于小儿及年轻病人