Embolic events in patients with atrial fibrillation and effective anticoagulation: value of transesophageal echocardiography to guide direct-current cardioversion. Final results of the Ludwigshafen Observational Cardioversion Study

OBJECTIVES: The primary objective was to evaluate the usefulness of transesophageal echocardiography (TEE)-guided cardioversion to prevent thromboembolic complications in patients with atrial fibrillation (AF) and effective anticoagulation (International Normalized Ratio of 2 or 3) at least three weeks before cardioversion. BACKGROUND: Transesophageal echocardiography has been proposed as a method of screening patients for left atrial thrombi before direct-current cardioversion of AF. The usefulness of TEE as a screening tool has always been evaluated in patients without long-term anticoagulation before cardioversion. METHODS: This prospective, single-center, observational study, performed on an intention-to-cardiovert basis, comprised 1,076 consecutive, unselected patients with AF. The initial two years were designed to be the control phase, during which the conventional approach was used. After that, cardioversion guided by TEE was performed in consecutive patients. RESULTS: The prevalence of left atrial thrombi was 7.7% in patients with persistent AF and effective anticoagulation. During the first four weeks after electrical cardioversion, six thromboembolic complications were observed in patients in whom the TEE-guided approach was employed (6 [0.8%] of 719 patients), compared with three thromboembolic complications in patients in whom the conventional approach was used (3 [0.8%] of 357 patients). None of the patients in whom electrical cardioversion was not performed experienced an embolic event. CONCLUSIONS: There were no differences in the rate of embolic events between the two treatment groups. In patients with AF and effective anticoagulation, TEE-guided electrical cardioversion does not reduce the embolic risk. However, TEE revealed left atrial thrombi in 7.7% of patients with AF and effective anticoagulation, before direct-current cardioversion.     

Intracardiac echocardiography guided device closure of atrial septal defects

OBJECTIVES: This study was designed to determine the feasibility and accuracy of intracardiac echocardiography (ICE) in guiding percutaneous closure of atrial septal defects (ASD). BACKGROUND: Intracardiac echocardiography is a novel imaging technique that might be used to guide interventional procedures. The sensitivity and specificity of ICE, compared to standard imaging techniques, in detecting potentially adverse procedural events and guiding remedial action will be an important consideration in its use. METHODS: In a prospective study, 24 patients underwent device closure of ASD using ICE as the primary echocardiographic imaging modality. Feasibility was expressed as proportion of cases in which complete diagnostic ICE imaging was achieved. Accuracy was expressed as the percent agreement between ICE and simultaneously performed transesophageal echocardiography (TEE). RESULTS: High-quality ICE images were acquired in all patients, though images were limited in two patients with aneurysmal septa. Intracardiac echocardiography successfully guided closure of 24 out of 25 ASDs (96%) in 23 patients. There was close agreement between ICE and TEE in their assessment of device position and the adequacy of septal capture before device release (98%) and in identifying the presence of significant residual shunts. Intracardiac echocardiography detected all potentially adverse events, including four malpositions, and guided appropriate remedial action. CONCLUSIONS: Intracardiac echocardiography guided device closure of secundum ASDs is feasible in the majority of patients and provides diagnostic data comparable to TEE. These data indicate that ICE may be used to guide routine closure of ASDs in adults without the need for TEE and general anesthesia.     

A comparison of pulmonary vein ostial anatomy by computerized tomography, echocardiography, and venography in patients with atrial fibrillation having radiofrequency catheter ablation

Accurate assessment of pulmonary vein anatomy is important to procedures that isolate these structures in patients with atrial fibrillation. Various modalities of pulmonary vein (PV) imaging are employed in clinical practice; however, the consistency of findings among the different modalities is unknown. The purpose of this study is to compare PV ostial anatomy by 4 common imaging techniques. Twenty-four patients undergoing catheter-based PV isolation procedures for atrial fibrillation had their PV ostial anatomy determined by cardiac computerized tomography (CT) and transesophageal echocardiography (TEE) before ablation and by intracardiac echocardiography (ICE) and venography during the ablation procedure. The number and maximal dimension of the PV ostia were determined by each imaging modality. In the 24 patients, 98 PV ostia were visualized by CT, 93 by ICE, 81 by TEE, and 71 by venography. The average ostial diameters were similar between CT (1.45 +/- 0.29 cm) and ICE (1.51 +/- 0.22 cm, p = 0.066). Compared with CT or ICE, the ostial diameters were larger with venography (1.67 +/- 0.32 cm) and smaller with TEE (1.16 +/- 0.28 cm, all p <0.001). PV ostial diameters as determined by ICE were significantly correlated with CT measurements (r = 0.57, p <0.001) and venography (r = 0.52, p <0.001). Venography measures of PV diameter were correlated with measures by CT (r = 0.33, p = 0.03). TEE measures were not correlated with any other modality (all p >/=0.43). CT identifies the greatest number of PV ostia followed by ICE. Venography overestimates and TEE underestimates ostial diameters compared with CT or ICE. The PV ostial dimensions obtained by ICE, CT, and venography are all significantly correlated.     

Transesophageal Echocardiography during Pulmonary Vein Cryoballoon Ablation for Atrial Fibrillation

We describe our first 20 cases of cryoablation of atrial fibrillation (AF) using transesophageal echocardiography (TEE). Continuous procedural monitoring with TEE by a cardiologist and senior sonographer assists the electrophysiologist in performance of the cryoballoon procedure of AF. Previously using intracardiac echocardiography (ICE) we have found TEE to have better overall procedural imaging, and monitoring for pericardial effusion or thrombus formation. We have found TEE monitoring to be helpful with positioning for interatrial septal (IAS) puncture, catheter tip avoidance of the left atrial appendage (LAA), and guidance of the balloon catheter into each pulmonary vein (PV), with proper positioning within each PV orifice, and documentation of PV occlusion for the cryoballoon procedure. Procedural equipment and the cryoballoon protocol used are presented in detail. The role of TEE imaging during the procedure and in preventing potential dangers is illustrated. It is the goal of this study to demonstrate how the electrophysiology and echocardiography laboratories work together in this cryoablation procedure.     

Role of echocardiography in percutaneous occlusion of the left atrial appendage

Percutaneous occlusion of the left atrial appendage (LAA) is a modern alternative for the treatment of patients with atrial fibrillation (AF) and with a high risk of stroke who are not eligible for long-term anticoagulation therapy. Echocardiography plays a significant role in selecting patients, guiding the procedure, and in the post-procedural follow-up. OBJECTIVES AND METHODS: To test the role of transesophageal echocardiography (TEE) and intracardiac echocardiography (ICE) in facilitating and shortening the procedure. RESULTS: ICE represents a more convenient approach in patients who are not under generally anesthesia and helps to facilitate transseptal puncture. On the other hand, TEE, having the ability to rotate the image plane, helps to better determine the position of the occluder. CONCLUSIONS: Echocardiographic guidance of this procedure is essential. Which approach will be preferred will depend on the development of these two methods.     

Cardioversion under the guidance of transesophageal echochardiograhy in persistent atrial fibrillation: results with low molecular weight heparin

BACKGROUND: Transesophageal echocardiography (TEE) guided cardioversion to restoration of sinus rhythm is a therapeutic option in patients with atrial fibrillation (AF). Anticoagulation at the time of and after cardioversion is necessary to prevent formation of new thrombus during atrial stunning period. We aimed to evaluate the efficacy and safety to TEE guided cardioversion with low molecular weight heparin (LMWH) in patients with atrial fibrillation. METHODS: We followed up 208 patients with persistent AF (mean age: 65.5+/-10.2 years) who were attempted TEE guided cardioversion. LMWH were used as an anticoagulant and warfarin therapy was continued. RESULTS: Cardioversion were performed in 183 patients. Sinus rhythm restored in 144 patients (78.7%). Mean follow up duration was 155 days. No cardiac death occurred. In the early follow up period (within 30 day) one thromboembolic event (0.54%) occurred in a patient who was cardioverted. Two patients who had not been cardioverted because of left atrial thrombus presented embolic stroke, one in early and another in late follow up period. All embolic complications occurred in patients who had been taking warfarin and whose INR level was subtherapeutic at the time of stroke. Sinus rhythm was maintained in 64% and total hemorrhagic complications occurred in 4.8% of the patients in long-term follow-up. CONCLUSION: TEE guided cardioversion with a short-term anticoagulation protocol using low molecular weight heparin is a safe and effective method in restoring and maintaining sinus rhythm and enables us to make earlier cardioversion in atrial fibrillation.     

Role of transesophageal echocardiography-guided cardioversion of patients with atrial fibrillation.

Electrical cardioversion of patients with atrial fibrillation (AF) is frequently performed to relieve symptoms and improve cardiac performance. Patients undergoing cardioversion are treated conventionally with therapeutic anticoagulation for three weeks before and four weeks after cardioversion to decrease the risk of thromboembolism. A transesophageal echocardiography (TEE)-guided strategy has been proposed as an alternative that may lower stroke and bleeding events. Patients without atrial cavity thrombus or atrial appendage thrombus by TEE are cardioverted on achievement of therapeutic anticoagulation, whereas cardioversion is delayed in higher risk patients with thrombus. The aim of this review is to discuss the issues and controversies associated with the management of patients with AF undergoing cardioversion. We provide an overview of the TEE-guided and conventional anticoagulation strategies in light of the recently completed Assessment of Cardioversion Using Transesophageal Echocardiography (ACUTE) clinical trial. The two management strategies comparably lower the patient's embolic risk when the guidelines are properly followed. The TEE-guided strategy with shorter term anticoagulation may lower the incidence of bleeding complications and safely expedite early cardioversion. The inherent advantages and disadvantages of both strategies are presented. The TEE-guided approach with short-term anticoagulation is considered to be a safe and clinically effective alternative to the conventional approach, and it is advocated in patients in whom earlier cardioversion would be clinically beneficial.     

Simultaneous transesophageal cardioversion and echocardiography: Feasibility and safety

BACKGROUND: Transesophageal echocardiography (TEE) is routinely used to exclude atrial thrombus prior to cardioversion of atrial fibrillation (AF). Because the TEE probe lies adjacent to the atria, cardioversion using an electrode attached to the TEE probe should allow for immediate low-energy transesophageal cardioversion. OBJECTIVE: The purpose of this study was to evaluate a cardioversion electrode sheath that can be affixed to conventional TEE probes for simultaneous thrombus exclusion and cardioversion of AF. METHODS: A thin electrode was integrated into a latex or polyurethane sheath covering a conventional TEE probe. TEE thrombus exclusion and biphasic transesophageal cardioversion using a step-up protocol were performed during deep sedation. Esophagoscopy was performed immediately after cardioversion and after 1 week. RESULTS: TEE was performed in 27 patients. One patient showed left atrial thrombi. Transesophageal cardioversion was successful in 25 of the remaining 26 patients. Mean atrial cardioversion threshold was 63 +/- 48 J. Transesophageal cardioversion restored sinus rhythm in two patients with unsuccessful transthoracic cardioversion. Transesophageal cardioversion in deep sedation was well tolerated. Esophagoscopy revealed slight mucosal damage in three patients at the site of shock application; two of these patients showed signs of gastroesophageal reflux disease. Mucosal damage unrelated to the site of shock delivery was noted in three patients. CONCLUSION: Atrial thrombus exclusion and transesophageal cardioversion of AF via a disposable cardioversion sheath offers the opportunity to perform transesophageal cardioversion and TEE thrombus exclusion during one sedation. It may not be suitable for use in patients with gastroesophageal reflux disease. Transesophageal cardioversion may establish sinus rhythm in selected patients refractory to transthoracic cardioversion.     

Echocardiographic Guidance of Percutaneous Patent Foramen Ovale Closure: Head‐to‐Head Comparison of Transesophageal versus Rotational Intracardiac Echocardiography

Background: Transesophageal (TEE) and intracardiac (ICE) echocardiography are commonly used to guide percutaneous patent foramen ovale (PFO) closure. The study aim was to perform a head‐to‐head comparison between TEE and rotational ICE echocardiography in the measurement of the fossa ovalis and device selection. Methods: In 45 patients with cryptogenic stroke or peripheral embolism and PFO with large right‐to‐left shunt, fossa ovalis dimensions were assessed preoperatively by TEE and intraoperatively by rotational ICE. The Amplatzer devices, deployed on the basis of ICE, were compared with those that would have been selected by TEE. Results: A good correlation between TEE and rotational ICE was observed for both longitudinal and transverse fossa ovalis dimensions (TEE four‐chamber vs. ICE four‐chamber: r = 0.75; TEE bicaval vs. ICE four‐chamber: r = 0.77; TEE aorta vs. ICE aorta: r = 0.59; P < 0.001 for all). However, no such correlation was found in 13 patients with atrial septal aneurysm (ASA) (TEE four‐chamber vs. ICE four‐chamber: r = 0.33; TEE bicaval vs. ICE four‐chamber: r = 0.49; TEE aorta vs. ICE aorta: r = 0.05; P = NS for all). At Bland‐Altman analysis, slight systematic differences with wide limits of agreement for each comparison were observed, particularly in patients with ASA, suggesting that the two imaging modalities cannot be used interchangeably. As regards device selection, a moderate agreement was found between TEE‐ and ICE‐guided device size (72%, κ= 0.53, P < 0.001), except in patients with ASA (36%, κ= 0.02, P = NS). Conclusions: Our study suggests a significant disagreement between TEE and rotational ICE in measuring fossa ovalis and selecting the device for PFO closure, particularly in patients with ASA.     

Intracardiac echocardiography: an ideal guiding tool for device closure of interatrial communications.

BACKGROUND: This study sought to evaluate safety and radiation exposure when using intracardiac echocardiography (ICE) in comparison to transesophageal echocardiography (TEE) in order to guide transcatheter closure of interatrial communications. METHODS: Eighty patients (44 males, 36 females, mean age 46, SD 13 years) undergoing device closure of atrial septal defect (n=12) or patent foramen ovale (n=68) had the procedure guided by ICE (n=50, group 1) or TEE (n=30, group 2). In group 1, all procedural stages were completely guided by ICE, including imaging of the interatrial communication during balloon sizing, device unfolding and release, and during the final check for adequate positioning. In group 2, exclusive implantation of devices was guided by use of TEE. RESULTS: Especially, the spatial relationship between device and cardiac structures (e.g. the ascending aorta, the interatrial septum and the superior vena cava) was accurately demonstrated in group 1. Image resolution provided by ICE was superior to that of TEE. No severe complications, including any related to ICE, were seen. Fluoroscopy time (FT) and procedure time (PT) were shorter in group 1 than in group 2 (FT: 5.5+/-1.5 min vs. 9.3+/-1.6 min, P<0.0001; PT: 31.9+/-4.6 min vs. 38.8+/-5.8 min, P<0.01). Neither sedation nor anesthesia was required in group 1. CONCLUSIONS: ICE is a safe tool to guide device closure of interatrial communications. For the patient, procedural stress and radiation exposure are negligible. ICE can be considered the guiding tool of choice for device closure, particularly when long or repeated echocardiographic viewing is required.     

Encerramento percutâneo de defeitos do septo interauricular guiado por ecocardiograma intracardíaco − A experiência de um centro

IntroductionDevice closure of interatrial communications has become a well-established technique to treat left-to-right shunt associated with atrial septal defect (ASD) and to prevent paradoxical embolism in patients with patent foramen ovale (PFO). Guidance by transesophageal echocardiography (TEE) is the standard practice but intracardiac echocardiography (ICE) is a feasible and safe alternative for monitoring these procedures.ObjectivesTo report our experience in the percutaneous closure of ASD and PFO guided by ICE.MethodsWe retrospectively reviewed all patients with ASD or PFO who underwent percutaneous closure guided exclusively by ICE between January 2008 and December 2010. All patients were followed clinically with regular echocardiographic evaluation (at discharge, one month, three, six and twelve months) to exclude residual shunt and device malposition.ResultsA total of 127 patients (mean age 46.6±12.2 years; 71% female) underwent transcatheter device closure of ASD or PFO during the study period. Device deployment with ICE monitoring was 100% successful, with a low rate of complications and eliminating the need for additional imaging techniques.ConclusionsICE provides anatomical detail of ASD/PFO and cardiac structures, facilitating congenital cardiac interventional procedures. It eliminates the major drawbacks associated with TEE and enables the interventional cardiologist to control all aspects of the procedure without relying on additional echocardiographic support.     

Atrial fibrillation and cardioversion: role of transesophageal echocardiography]

The most common cardiac arrhythmia is atrial fibrillation (AF). Echocardiography has been an important tool in the evaluation of patients with AF. Transesophageal echocardiography (TEE) offers excellent visualization of the atria and accurate identification or exclusion of atrial thrombi. Patients undergoing cardioversion are treated conventionally with therapeutic anticoagulation for 3 weeks before and 4 weeks after cardioversion to decrease the risk of thromboembolism. A TEE-guided strategy has been proposed as an alternative that may lower stroke and bleeding events. Patients without atrial thrombus by TEE are cardioverted on achievement of therapeutic anticoagulation, whereas cardioversion is delayed in patients with any thrombus. The two management strategies comparably lower the patient's embolic risk when the guidelines are properly followed. The TEE-guided approach offers the advantage of simplified anticoagulation management and may lower the incidence of bleeding complications.     

Use of Intracardiac Compared With Transesophageal Echocardiography for Left Atrial Appendage Occlusion in the Amulet Observational Study

ObjectivesThe aim of this study was to compare patient and procedural characteristics, clinical events, and left atrial appendage (LAA) occlusion rates among implantation procedures guided either by intracardiac echocardiography (ICE) or by transesophageal echocardiography (TEE) in the Amulet Observational Study.BackgroundTEE is standard for intraprocedural imaging during LAA occlusion. ICE is an alternative enabling local rather than general anesthesia.MethodsThe Amulet Observational Study is a prospective, multicenter, post-market study of the Amulet device in patients with atrial fibrillation at risk for thromboembolism from the LAA. Procedures were guided by ICE in the left atrium or TEE. A clinical events committee adjudicated serious adverse events. LAA closure was assessed by a core laboratory 1 to 3 months post-implantation.ResultsNine hundred fifty-five procedures were TEE guided and 130 (12%) were ICE guided. Local anesthesia was used in 93% of ICE-guided cases. Implantation success was >99% in both groups (p = 1.00). The procedure was longer (40 ± 31 min vs. 33 ± 21 min; p = 0.01) and contrast use higher (145 ± 157 ml vs. 98 ± 76 ml; p < 0.01) for ICE cases. LAA closure rate was 100% using ICE and 98% using TEE. Vascular access serious adverse events occurred in 0.8% of ICE patients and 1.5% of TEE patients (p = 0.52). Pericardial effusions or tamponade was observed at rates of 2.5% per year and 1.7% per year in ICE and TEE patients, respectively (p = 0.57). Rates of ischemic stroke (4.1% per year vs. 2.6% per year; p = 0.37) and major bleeding (8.2% per year vs. 10.6% per year; p = 0.44) did not differ significantly between ICE and TEE patients.ConclusionsAmulet LAA occlusion procedures guided by ICE and TEE resulted in comparable clinical event and LAA closure rates, without differences in procedural or vascular complications despite longer procedures and more contrast use.     

Comparative assessment of left atrial appendage by transesophageal and combined two- and three-dimensional transthoracic echocardiography

Objective: Our objective was to compare the utility of combined two‐dimensional (2D) transthoracic echocardiography (TTE) and three‐dimensional (3D) TTE versus 2D transesophageal echocardiography (TEE) in evaluation of the left atrium (LA) and LA appendage (LAA) for clot. Background: 2DTEE, usually performed to visualize the LAA, is semi‐invasive and not without risks. With improved technology the LAA has been increasingly visualized by 2DTTE and 3DTTE in many patients. Methods: We compared combined 2DTTE and 3DTTE with 2DTEE in evaluating the LA/LAA for a thrombus. Ninety‐two patients underwent 2DTTE, 3DTTE, and 2DTEE. An additional 20 patients, in whom TEE could not be performed, underwent 2DTTE and 3DTTE. Results: LA and LAA could be visualized in all patients. Of 92 patients studied, 74 had no thrombus and 7 had thrombus in the LAA by all modalities. Eleven patients, 9 with atrial fibrillation (AF), had a suspected thrombus by 2DTEE, but 3DTTE cropping clearly showed these to be prominent pectinate muscles which were seen in short axis on 2DTEE as rounded echo dense masses and therefore mimicked thrombi. These 9 patients with AF underwent successful cardioversion without any complications. Of the 20 patients in whom TEE could not be performed, 19 had no thrombus in the LA/LAA and 1 had a clot in the LAA. These 19 patients underwent successful cardioversion without complications. Conclusions: Our preliminary study suggests that combined 2DTTE and 3DTTE has comparable accuracy to TEE in evaluating the LA and LAA for thrombus. In some patients TEE, but not 3DTTE, may misdiagnose pectinate musculature as thrombus.     

Registo de encerramento percutâneo do apêndice auricular esquerdo e experiência inicial com ecografia intracardíaca

Introduction

Percutaneous closure of the left atrial appendage (LAA) is a promising therapy in patients with atrial fibrillation with high risk for stroke and contraindication for oral anticoagulation (OAC). Intracardiac echocardiography (ICE) may make this percutaneous procedure feasible in patients in whom transesophageal echocardiography (TEE) is inadvisable. Our aim was to assess the efficacy and safety of LAA closure and the feasibility of ICE compared to TEE to guide the procedure.

Use of intracardiac echocardiography to guide implantation of a left atrial appendage occlusion device (PLAATO).

BACKGROUND: Over 90% of thrombi in atrial fibrillation (AF) originate from the left atrial appendage (LAA). Patients with contraindications to anticoagulation are potential candidates for LAA occlusion using the Percutaneous Left Atrial Appendage Transcatheter Occlusion system (PLAATO, ev3 Inc., Plymouth, MN). Transesophageal echocardiography (TEE) is typically used to guide implantation. OBJECTIVE: This study sought to examine the utility of intracardiac echocardiography (ICE) in providing adequate imaging guidance as an alternative to TEE during PLAATO implantation. METHODS: The study group consisted of 10 patients who underwent PLAATO implantation with simultaneous TEE and ICE imaging guidance. ICE was used to perform the following tasks typically fulfilled by TEE: (1) verification of the absence of LAA thrombus, (2) identification of the LAA ostial dimension for device sizing, (3) guidance of transseptal puncture, (4) verification of the delivery sheath position, and (5) confirmation of location and stability of device before its irrecoverable release. The ability of ICE to perform these tasks was assessed from three separate positions: the standard right atrial (RA) position, within the coronary sinus (CS), and the right ventricular outflow tract. RESULTS: ICE imaging of the LAA was optimal from within the CS, although imaging from the proximal pulmonary artery provided better visualization of the distal LAA in cross-section. The LAA dimensions, confirmation of the absence of LAA thrombus, proper positioning of the delivery sheath, verification of location and stability of the device obtained by ICE were consistent with findings from TEE. CONCLUSION: Using nonconventional imaging planes, ICE imaging was able to perform the intraprocedural functions provided by TEE during implantation of the PLAATO left atrial appendage occlusion device.     

房间隔缺损并发心房纤颤患者应用Amplatzer伞封堵房缺后心房纤颤的电复律治疗

目的 :初步评价房间隔缺损并发心房纤颤患者应用 Am platzer伞封堵房间隔缺损后心房纤颤的电复律疗效。方法 :2例患者 （5 1～ 5 3岁 ）。在透视及食管超声心动图监视下经导管置入 Amplatzer伞封堵房间隔缺损。术后即时行超声心动图 ,术后 2 4h,和 1,3,6月 ,分别行经胸超声心动图评价房间隔缺损治疗效果。术后 6月行电复律。结果 :2例患者疗效均佳 ,房间隔未见残余分流 ,电复律成功 ,患者转为窦性心律 ,复律后无并发症及 Amplatzer伞移位。结论 :应用 Am platzer伞封堵房间隔缺损并发心房纤颤患者 ,电复律易成功 ,是一种安全有效的复律方法。     

A comparison of intracardiac and transesophageal echocardiography to detect left atrial appendage thrombus in a swine model

Purpose

Transesophageal echocardiography (TEE) is the gold standard in the evaluation for left atrial appendage (LAA) thrombus in patients with atrial fibrillation (AF) and is often performed prior to AF ablation. We routinely use intracardiac echocardiography (ICE) to assist in AF ablation; however, standard right atrial views do not provide adequate visualization of the LAA. As the incidence of thrombus in this population is relatively low, TEE incurs additional risk, cost, and patient discomfort. Novel views of the LAA with ICE may obviate the need for TEE in this population. We tested the hypothesis that due to their proximity, imaging the LAA from the pulmonary artery (PA) would provide equivalent sensitivity and specificity to TEE in detecting LAA thrombus in a swine model.

Methods

Five domestic swine were utilized. Baseline images of the LAA with TEE were obtained. An 8Fr ICE catheter was placed in the left main PA, and imaging of the LAA was repeated. After transseptal puncture, an admixture of 2 cm³ blood and 1,000 IU of thrombin was injected into the LAA, and imaging of the LAA was repeated. Two blinded, independent reviewers experienced in ICE assessed the images and adjudicated both the presence of thrombus and the subjective image quality.

Results

The presence or absence of thrombus was correctly identified in all cases by both reviewers. Both reviewers rated the subjective quality of ICE images superior to TEE.

Conclusions

ICE is equivalent to TEE in imaging LAA thrombus in a porcine model. Whether ICE can provide similar diagnostic accuracy and safety for detecting LAA thrombus in humans remains unproven.     

非瓣膜病心房颤动病人电复律前后左心房功能变化研究

目的评价经食道超声心动图(TEE)对非瓣膜病心房颤动(房颤)病人电复律前后左心房功能变化.方法选择房颤持续2周以上的非瓣膜疾病病人18例,其中原发性高血压6例,扩张型心肌病6例,脑血栓4例,缺血性心肌病2例.应用TEE确定左心房内无血栓后行电复律,转为窦性心律者测定左心耳血流最大速度及流速积分,肺静脉血流最大速度及流速积分、二尖瓣血流最大速度、流速积分及减速时间.结果左心耳排空速度于复律后显著减少,有显著性差异(P＜0.05),排空指数增加(P＞0.05),电复律后肺静脉收缩期、舒张期最大流速及其流速积分比值无显著差异(P＞0.05),收缩期最大流速积分在左、右肺静脉均有显著差异(P均＜0.05).复律前后舒张期最大流速积分在右肺静脉有显著性差异(P＜0.05),左肺静脉差异不显著(P＞0.05).二尖瓣血流E波最大速度及E波与A波比值(E/A)增加.结论适合的抗凝治疗及TEE确认心房内无附壁血栓后进行电复律治疗,安全又无并发症.TEE能评价房颤病人电复律后的左心房功能变化.电复律后心房的电活动及机械活动均微弱,能引起左心房功能不全及栓塞,所以心房功能完全恢复前均有必要进行抗凝治疗.     

Transesophageal Echocardiography to Guide Cardioversion in Patients with Atrial Fibrillation: ACUTE Trial Update

The Assessment of Cardioversion Using Transesophageal Echocardiography (ACUTE) trial was the first randomized prospective study to compare the conventional strategy of 3 weeks of anticoagulation before direct current cardioversion (DCC) for atrial fibrillation (AF) to a transesophageal echocardiography (TEE) guided approach with an expedited course of anticoagulation. This was a multicenter, international study with 70 sites enrolling 1222 patients between 1994-1999. The primary endpoint of composite embolic events and secondary endpoints including bleeding, functional status, prevalence of sinus rhythm, and death were assessed at 8 weeks following randomization.The ACUTE trial demonstrated that the TEE guided approach was safe and effective. There was no difference in the primary outcome of embolic events for the 2 strategies (0.8% TEE group vs. 0.5% conventional group, p =.50). There was a difference between the groups with respect to the number of bleeding events, with minor and major bleeding seen in 2.9% of patients in the TEE guided group and 5.5% in the conventional group (relative risk 0.53, 95% confidence interval 0.30-0.93, p = 0.03). The remaining secondary endpoints did not differ.Clinicians now have a viable alternative approach to cardioversion for patients with AF. Several factors influence the choice of strategies including (1) severity of symptoms and hemodynamic effect; (2) level and chronicity of anticoagulation; (3) risks of bleeding; (4) duration of AF and likelihood of reversion; and (5) risk and likelihood of left atrial thrombi. Future studies, such as ACUTE II are ongoing, with the aim of using low molecular weight heparin to further streamline the TEE guided approach to DCC and shorten hospital stay and costs.