Targeting Atrio-Atrial Conduction in the Post-Orthotopic Heart Transplant Patient

The ICE CHIP study is a sequential Phase I and Phase II pilot study comparing the cardiac imaging capabilities of intracardiac echocardiography (ICE) with with transesophageal echocardiography (TEE) followed by a randomized comparison of ICE guided cardioversion with a conventional cardioversion strategy in patients with atrial fibrillation. It is a prospective open label randomized multi-center investigation performed in two phases designed to initially compare two distinct imaging modalities (Phase 1) and subsequently two different strategies (ICE guided Cardioversion and Conventional) in the management of AF in patients undergoing invasive cardiac procedures in whom electrical cardioversion is indicated (Phase 2). This study will examines two hypotheses in AF patients undergoing invasive cardiac procedures: (1) ICE has comparable efficacy to TEE in visualization of left atrial pathology including thrombi or interatrial septal defects. This will be evaluated during the Phase I component of the study. (2) ICE can identify low risk patients in whom immediate cardioversion during the procedure is safe and comparably effective to electrical cardioversion performed based on a conventional strategy of a minimum of 3 weeks of preceding anticoagulation therapy. Phase 1 will enroll 100 patients at 12 centers, who will undergo a clinically indicated TEE procedure and cardiac catheterization procedure. Each patient will be imaged by TEE &; ICE and a core echo laboratory will perform a blinded comparison of the two imaging modalities. In Phase 2, a total of 300 patients (3:2 randomization) will be enrolled in the study at up to 15 investigational sites in USA and Europe. The composite incidence rate of major cardiac and bleeding complications (stroke, TIA, peripheral embolism, major hemorrhagic event) will be compared between the two treatment groups over the duration of the study.     

Intracardiac echocardiography for guidance of transcatheter left atrial appendage occlusion: An expert consensus document

Transcatheter left atrial appendage occlusion (LAAO) is an increasingly used alternative to oral anticoagulation in selected patients with atrial fibrillation. Intraprocedural imaging is a crucial for a successful intervention, with transesophageal echocardiography (TEE) as the current gold standard. Since some important limitations may affect TEE use, intracardiac echocardiography (ICE) is increasingly used as an alternative to TEE for guiding LAAO. The lack of a standardized imaging protocol has slowed the adoption of ICE into clinical practice. On the basis of current research and expert consensus, this paper provides a protocol for ICE support of left atrial appendage occlusion.     

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.     

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.     

Initial clinical experience with intracardiac echocardiography in guiding transcatheter closure of perimembranous ventricular septal defects: feasibility and comparison with transesophageal echocardiography.

Over the last several years, intracardiac echocardiography (ICE) has been employed successfully in guiding transcatheter device closure of a secundum atrial septal defect (ASD) or patent foramen ovale (PFO). Nothing is known regarding the use of ICE to guide catheter device closure of a perimembranous ventricular septal defect (PMVSD). Twelve patients (seven female/five male) who had a PMVSD (among them, three patients with associated atrial communications: two with an ASD and one with a PFO) underwent attempts at transcatheter device closure using the Amplatzer membranous VSD device of their defects, using sequential transesophageal echocardiography (TEE) and ICE guidance with general endotracheal anesthesia (five patients) and using ICE alone with conscious sedation (seven patients). The mean age of patients was 16.9 +/- 3.7, and their mean weight was 42.4 +/- 6.6. Their mean left ventricular end-diastolic dimension preclosure was 45.7 +/- 2.5. The Qp/Qs ratio ranged from 1.0 to 1.8:1. During the procedure, the ICE catheter was positioned in the right atrium (RA) in all 12 patients and the ICE catheter was advanced to the left atrium to obtain a view of the ventricular septum in 3. Both TEE and ICE provided similar anatomical views of the position of the PMVSD. Furthermore, the relationship of the defect to the aortic valve and tricuspid valves, the measured size of defect, and the guidance of various stages of device deployment were comparable by TEE and ICE. There were no complications encountered during or after closure. We conclude that ICE provides unique images of the PMVSD and measurements similar to those obtained by TEE. ICE potentially could replace TEE in most patients as a guiding imaging tool for PMVSD device closure, thus eliminating the need for general endotracheal anesthesia.     

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.     

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.     

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 versus transesophageal echocardiography for left atrial appendage occlusion with watchman

Background: Left atrial appendage occlusion (LAAO) is mostly performed by transesophageal echocardiography (TEE) guidance. Intracardiac echocardiography (ICE) may be an alternative imaging modality for LAAO that precludes the need for general anesthesia or sedation. Methods and Results: All consecutive single center, single operator LAAO candidates were analyzed. Baseline clinical and procedural characteristics and in‐hospital outcomes were compared between patients in whom a Watchman was implanted with ICE vs. TEE guidance. In 76 consecutive patients the Watchman device was deployed under ICE in 32 patients (42%) and under TEE guidance in 44 patients (58%). Baseline characteristics were comparable between groups, except that patients in the TEE group were older (81 [75–85] years vs. 75 [68–80] years, P = 0.007). Total injected contrast media as well as fluoroscopy time were comparable between groups (90 ml [54–140] vs. 85 ml [80–110], P = 0.86 and 7.9 min [6.4–15.5] vs. 9.8 min [7.0–13.2], P = 0.51, for TEE vs. ICE, respectively). However, time from femoral venous puncture to transseptal puncture and to closure was longer in the ICE group (14 min [7.3–20] vs. 6 min [3.3–11], P = 0.007 and 48 min [40–60] vs. 34.5 min [27–44], P = 0.003, respectively). In the TEE group one patient suffered esophageal erosion with bleeding, which was managed conservatively and one non‐LAAO related in‐hospital mortality occurred in an 88‐year‐old patient. Device implantation success rate was 100% in both groups. No device embolization, no significant peri‐device leak, no tamponade, no stroke, and no access site bleeding occurred in any patient. Total hospital stay for stand‐alone LAAO was comparable between groups (2 days [2–2] vs. 2 days [2–3.3], P = 0.17, in ICE vs. TEE, respectively). Conclusions: ICE guidance for LAAO with the Watchman device is feasible and comparable to TEE and may become the preferred imaging modality for LAAO. © 2016 Wiley Periodicals, Inc.     

Value of trans-oesophageal echocardiography as a method of encouraging patients with chronic atrial fibrillation to use anticoagulation therapy

Background

Despite the indisputable role of anticoagulation therapy for atrial fibrillation (AF) patients at risk for stroke, anticoagulants remain under-used in everyday clinical practice. We assumed that by performing trans-oesophageal echocardiography (TEE) on patients with AF who were not on anticoagulation treatment prior to the procedure, and by explaining to them the TEE images obtained, as well as the possible consequences of these findings, we could convince patients to start anticoagulation therapy. The main objective of the study was to assess the examined patients’ adherence to warfarin therapy over a two-year period.

Methods and results

We conducted a prospective TEE study from February 2006 to December 2008 on 70 patients with chronic AF who were not on anticoagulation treatment. Mean patient age was 65.85 ± 10.02 years and 68.57% were women. Thrombus in the left atrial appendage was found in 25 (35.71%) patients. Fifty-four (77.14%) patients had thrombi or spontaneous echo contrast in at least one of their supraventricular cavities.Following the procedure and with detailed explanation to the patients of their TEE findings, we managed to start anticoagulation therapy on 60 (85.71%) patients. At the end of the follow-up period of 23.76 ± 2.8 months, 53 (75.71%) patients remained on warfarin therapy. The rest of the surviving patients settled for thrombo-prophylaxis with aspirin.

Conclusion

TEE is a valuable method that, in addition to its diagnostic possibilities, could also serve as a convincing visual method of putting atrial fibrillation patients onto an anticoagulation regimen.     

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.     

特殊类型房间隔缺损的介入治疗及远期随访观察

目的:探讨特殊类型房间隔缺损(ASD)介入治疗的适应证及注意事项,观察其术后远期疗效及安全性。方法:我院1999-12-2009-01期间经胸和(或)经食管超声心动图(TTE、TEE)行术前筛选并成功随访的特殊类型ASD患者116例,评估后应用房间隔封堵器(ASO)介入封堵,于术后远期随访观察并发症的发生,同时追踪心脏超声及心电图变化。结果:所有患者术后随访40～120(90±46)个月。111例封堵成功,技术成功率95.7%;随访中发生严重并发症4例(3.6%),其中1例封堵器脱落,1例溶血,1例脑栓塞及1例明显主动脉瓣反流;手术成功率为94.8%(110/116);9例(8.2%)术后即刻有残余分流,随访中5例分流消失,完全封闭率96.4%;ASD患者术后心脏重构较术前显著改善,尤以年龄<18岁者改善明显;术前心电图2例存在室上性心动过速,随访中未见再发作;5例心房颤动,随访中2例恢复窦性心律,未见室性心律失常,24例原有右束支传导阻滞,术后6例消失。结论:术前了解ASD解剖细节,严格掌握适应证是ASO治疗特殊类型ASD手术成功的关键,远期随访疗效肯定。     

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.

Intracardiac Versus Transesophageal Echocardiographic Guidance for Left Atrial Appendage Occlusion: The LAAO Italian Multicenter Registry

Objectives

This study sought to evaluate the feasibility, safety, and efficacy of intracardiac echocardiography (ICE)–guided versus transesophageal echocardiography (TEE)–guided left atrial appendage occlusion (LAAO) by the use of Amplatzer Cardiac Plug or Amulet devices included in a large Italian registry.

Intracardiac echocardiography to guide closure of atrial septal defects in children less than 15 kilograms.

BACKGROUND: Intracardiac echocardiography (ICE) is increasingly replacing transesophageal echocardiography (TEE) as the primary imaging technique to guide device closure of atrial septal defects (ASD). Owing to the length of the procedure, the use of TEE requires general anesthesia. Investigators have reported the usefulness of ICE in adults and children. However, little is known about the use of ICE in children whose weight is <15 kg. Therefore, this study examines the use of ICE guided secundum ASD closure in children <15 kg. METHODS: Nineteen patients with a median age of 3.1 years (range 1.8-4.8), and median weight of 13.2 kg (range 8.0-14.4) underwent transcatheter occlusion (Amplatzer occluder) of a secundum ASD using ICE guidance. ICE was performed using an Acunav catheter. The ICE catheter (10 F shaft) was introduced into an 11 F sheath in a contralateral femoral vein. Diagnostic as well as periprocedure imaging was obtained. RESULTS: Sixteen patients had single, and three had multiple defects. Median defect size as measured by ICE was 16 mm (range 2.5-25). The median balloon stretched diameter (obtained in eight patients) was 18 mm (range 10-21); the median size of the defect for these eight patients was 15 mm (range of 8-20). Both techniques for measuring the defect correlated well with r = 0.94. The ASD occluder size ranged from 7 to 26 mm with a median of 18 mm. The procedure was successful in 16 patients who had a device implanted and no residual shunt. ASD occlusion was not attempted in two patients due to deficient rims and in one patient, the attempt failed due to left atrial disk prolapse through the ASD. Four patients experienced transient complications during the catheter procedure, including supra ventricular tachycardia, sinus bradycardia, and two with complete heart block (resolving with device removal); all had subsequent successful device placement. No complications were attributed to the use of ICE and specifically, no vascular injury was noted. CONCLUSIONS: Comparable to results with larger patients, ICE provides adequate imaging (preprocedure diagnosis and periprocedure guidance) during device occlusion of secundum ASDs with no significant complications. Thus, ICE can successfully be used in the closure of ASD in smaller patients (<15 kg) and eliminate the need for endotracheal intubation.     

Low incidence of left atrial or left atrial appendage thrombus in patients with paroxysmal atrial fibrillation and normal EF who present for pulmonary vein antrum isolation procedure

Introduction: The incidence of left atrial appendage (LAA) thrombus in patients with paroxysmal atrial fibrillation (PAF) who present for pulmonary vein antrum isolation procedure (PVAI) is unknown.
Methods and Results: All consecutive patients from January 2000 to June 2004 who underwent a PVAI received a computed tomography (CT) to evaluate LAA thrombus before the procedure and 3 months post-PVAI. All patients were followed prospectively. One thousand two hundred twenty-one patients received a PVAI during the study dates. All patients received a CT pre-PVAI at 3 months, and 601 (49%) received a transesophageal echocardiography (TEE) pre-PVAI. Per protocol, all patients who had CT scans that were positive for LAA thrombus received a TEE. There were 9 patients who had LAA thrombus on CT scan, but only 3 had LAA thrombus on TEE. Using TEE as the gold standard, only 3 patients had an LAA thrombus before PVAI; of these patients, 2 had chronic AF with average ejection fraction (EF) of 48% and 1 patient had PAF with EF 25%. No patients with PAF and normal EF had LAA thrombus. Patients with LAA thrombus pre-PVAI had lower EF than patients without LAA thrombus (40% vs. 53%, P = 0.007) but had similar LA size (5.0 vs. 4.5 cm, P = 0.77). No other differences in baseline characteristics were noted.
Conclusions: In this registry of 1,221 patients, we did not observe LA thrombus in PAF patients with normal EF who present for PVAI. Prescreening CT alone is likely to be sufficient in paroxysmal AF patients with normal EF, and the use of TEE may not be needed.     

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.     

Implantation of left atrial appendage occlusion devices and complex appendage anatomy: the importance of transesophageal echocardiography

Percutaneous delivery of left atrial appendage (LAA) occluding devices represents a novel approach for stroke prevention in patients with atrial fibrillation. Transesophageal echocardiography (TEE) has a pivotal role throughout these procedures, facilitating device size selection and ensuring optimal deployment of the device. We report a case of an LAA occluding device implantation in which apparent proper positioning on fluoroscopy was determined by TEE to be malpositioning with a nonocclusive, perpendicular orientation to the plane of the LAA ostium. This problem appeared to be related to a complex, multilobed LAA anatomy and was readily resolved by repositioning of the device under TEE guidance.     

Transcatheter closure of atrial septal defects and patent foramen ovale under intracardiac echocardiographic guidance: feasibility and comparison with transesophageal echocardiography.

Transesophageal echocardiography (TEE) has been employed successfully for guiding transcatheter device closure of secundum atrial septal defect (ASD) and patent foramen ovale (PFO). However, the use of TEE for device closure requires general anesthesia. Intracardiac echocardiography (ICE) can provide similar anatomical views that might replace the use of TEE for device closure. Eleven patients (eight female/three male) with secundum ASD and PFO associated with strokes underwent attempts at transcatheter closure of their defects under sequential TEE and ICE guidance (six patients) and under ICE alone (five patients). The ages of the patients ranged from 6.6 to 74.7 yr, and their weights ranged from 23 to 124.5 kg. The sizes of the defects, as measured by TEE (six patients), ranged from 3 to 27 mm and, as measured by ICE (11 patients), from 3 to 27 mm. The balloon-stretched diameter of the ASD, as measured by TEE (six patients), ranged from 16 to 38 mm and, as measured by ICE (11 patients), from 16 to 35 mm. Both techniques correlated well for the measured two-dimensional diameter and for the balloon-stretched diameter (r = 0.97 and 0.98, respectively). Both TEE and ICE provided similar views of the defects and the various stages of device deployment. Owing to the proximity of the left atrium to the esophagus, however, the images obtained by ICE were more helpful and informative than those obtained by TEE. All patients experienced successful device placement (six patients under both TEE and ICE; five patients under ICE guidance alone); complete closure of the defects was effected in nine patients, whereas two patients had small residual shunts. There were no complications. We conclude that ICE provides unique images of the atrial communications and measurements similar to those obtained by TEE. ICE potentially could replace TEE as a guiding imaging tool for ASD and PFO device closure, thus eliminating the need for general anesthesia.     

Diagnostic accuracy of arterial phase 64-slice multidetector CT angiography for left atrial appendage thrombus in patients undergoing atrial fibrillation ablation

Introduction: Multidetector CT (MDCT) is used prior to atrial fibrillation ablation (AFA) to anatomically guide ablation procedures. Whether 64-slice MDCT also can be used to diagnose left atrial thrombus is not known.
Methods: We sought to determine the accuracy and interobserver variability of MDCT in the evaluation of left atrial thrombus prior to AFA. We enrolled 50 patients scheduled for AFA who underwent 64-slice MDCT scan and transesophageal echocardiography prior to the procedure. Three experienced observers reviewed all the MDCT images for the presence of a left atrial thrombus, and two different readers interpreted the transesophageal echocardiograms (TEE), which were used as the gold standard. All observers were blinded to clinical data and each other.
Results: Interobserver variability between the three MDCT readers was poor (highest kappa statistic 0.43, P = 0.001). Diagnostic accuracy was highly variable, with sensitivities ranging from 100% to 50% and specificities ranging from 85% to 44%. TEE reader agreement was 98%.
Conclusion: MDCT demonstrates high interobserver variability and has only modest diagnostic accuracy for the detection of left atrial thrombus in patients undergoing AFA procedure. Potential factors affecting the accuracy of MDCT include image quality and the difficulty of distinguishing clot from pectinate muscle. MDCT likely is not the optimal method to detect left atrial thrombus using current techniques and standards of interpretation.