Use of real time three-dimensional transesophageal echocardiography in intracardiac catheter based interventions

Three-Dimensional Transesophageal Echocardiography in Percutaneous Catheter-Based Cardiac Interventions

Cardiac structural and valve interventions have remained surgical procedures for several decades. The ability to directly visualize the region of interest during surgery made imaging of these structures pre- and postsurgery a secondary tool to compliment surgical visualization. The last two decades, however, have seen rapid advances in catheter-based percutaneous structural heart interventions (SHIs). Due to the "blind" nature of these interventions, imaging plays a crucial role in the success of these procedures. Fluoroscopy is used universally in all percutaneous cardiac SHIs and helps primarily in the visualization of catheters and devices. However, success of these procedures requires visualization of intracardiac soft tissue structures. Due to its portable nature and rapid ability to show cardiac structures online, transesophageal echocardiography (TEE) has become an integral tool for guidance for all percutaneous SHI. Transcatheter aortic valve replacement-one of the earliest catheter-based procedures-while initially dependent on TEE, has largely been replaced by preprocedural cardiac CT for accurate assessment of valve sizing. Developments in echocardiography now allow live three-dimensional (3D) visualization of cardiac structures mimicking surgical anatomy during TEE. Besides showing actual 3D intracardiac structures, 3D-TEE allows visualization of the interaction of intracardiac catheters and devices with soft tissue cardiac structures, thereby becoming a "second pair of eyes" for the operator. Real-time 3D-TEE now plays an important role complementing multiplane two dimensional and biplane TEE during such interventions. In this review, we discuss the incremental role of 3D-TEE during various SHIs performed today.

Complications Associated With Transesophageal Echocardiography in Transcatheter Structural Cardiac Interventions

BACKGROUND

Transesophageal echocardiograms (TEEs) performed during transcatheter structural cardiac interventions may result in greater complications than those performed in the nonoperative setting or even those performed during cardiac surgery. However, there are limited data on complications associated with TEE during these procedures. We evaluated the prevalence of major complications among these patients in the United States.

METHODS

A retrospective cohort study was conducted using an electronic health record database (TriNetX Research Network) from large academic medical centers across the United States for patients undergoing TEE during transcatheter structural interventions from January 2012 to January 2022. Using the American Society of Echocardiography-endorsed International Statistical Classification of Diseases and Related Health Problems Clinical Modifications (10th edition) codes, patients undergoing TEE during a transcatheter structural cardiac intervention, including transaortic, mitral or tricuspid valve repair, left atrial appendage occlusion, atrial septal defect closure, patent foramen ovale closure, and paravalvular leak repair, were identified. The primary outcome was major complications within 72 hours of the procedure (composite of bleeding and esophageal and upper respiratory tract injury). The secondary aim was the frequency of major complications, death, or cardiac arrest within 72 hours in patients who completed intraoperative TEE during surgical valve replacement.

RESULTS

Among 12,043 adult patients (mean age, 74 years old; 42% female) undergoing TEE for transcatheter structural cardiac interventions, 429 (3.6%) patients had a major complication. Complication frequency was higher in patients on anticoagulation or antiplatelet therapy compared with those not on therapy (3.9% vs 0.5%; risk ratio [RR] = 8.09, P < .001). Compared with those patients <65 years of age, patients ≥65 years of age had a higher frequency of major complications (3.9% vs 2.2%; RR = 1.75, P < .001). Complication frequency was similar among male and female patients (3.5% vs 3.7%; RR = 0.96, P = .67). Among 28,848 patients who completed surgical valve replacement with TEE guidance, 728 (2.5%) experienced a major complication.

CONCLUSIONS

This study found that more than 3% of patients undergoing TEE during transcatheter structural cardiac interventions have a major complication, which is more common among those on anticoagulant or antiplatelet therapy or who are elderly. With a shift of poor surgical candidates to less invasive percutaneous procedures, the future of TEE-guided procedures relies on comprehensive risk discussion and updating practices beyond conventional methods to minimize risk for TEE-related complications.

Intracardiac Echocardiogram: Feasibility, Efficacy, and Safety for Guidance of Transcatheter Multiple Atrial Septal Defects Closure

We aimed to determine the feasibility, efficacy, success, and safety of intracardiac echocardiography (ICE) in transcatheter multiple atrial septal defect (ASD) closure. Of 185 patients with multiple ASDs who underwent transcatheter closure, 140 (76%) patients who weighed <30kg with a narrow distance between defects or in whom single device closure was anticipated were guided by ICE and 45 patients were guided by three-dimensional (3D) transesophageal echocardiography (TEE) with or without ICE. Patients in the ICE group were relatively younger and weighed less than those in the 3D TEE group (p < 0.0001). The ratio of the distance between defects >7 mm was high, and more cases required ≥2 devices in the 3D TEE group than those in the ICE group (p < 0.0001). All patients in the 3D TEE group and seven patients (5%) in the ICE group were operated on under general anesthesia (p < 0.0001). The fluoroscopic time was shorter in the ICE group (13.98 ± 6.24 min vs. 24.86 ± 16.47 min, p = 0.0005). No difference in the complete closure rate and complications was observed. ICE-guided transcatheter and 3D TEE were feasible, safe, and effective in successful multiple ASD device closures, especially for young children and patients at high risk under general anesthesia.

Mitral valve paravalvular leaks: Comprehensive review of literature

BACKGROUND

Mitral paravalvular leaks (mPVL) are a recognized complication for patients with mitral valve prostheses. Although clinically insignificant for many patients, it may pose life-threatening haemolysis and regurgitation-induced heart failure, and so clinicians should have a high index of suspicion in the presence of new symptoms.

AIMS

This review discusses the pathogenesis, clinical features, diagnosis, imaging and treatment of mPVLs.

METHODS

A comprehensive literature search was performed using PubMed, EMBASE, Cochrane database, Google Scholar and Ovid. Search terms used included "mitral valve paravalvular leak," "transthoracic echocardiography," "2D transoesophageal echocardiography," "3D transoesophageal echocardiography," "cardiac computed tomography," (CT) "cardiac magnetic resonance imaging," "intracardiac echocardiography," "cinefluoroscopy," "fluoroscopy," and "percutaneous closure."

RESULTS

All patients with mPVLs should undergo regular full evaluation, including patient history, physical examination, laboratory work-up, imaging, and referral, if necessary. Echocardiography is fundamental to the diagnosis, and is augmented with cardiac magnetic resonance imaging, cardiac computerized tomography and fluoroscopy for further characterization and procedural planning amongst the structural heart team.

CONCLUSION

The prevalence of mPVL is expected to increase proportionally to the growing number of surgical and transcatheter valve replacements conducted in the ageing population. Multimodal imaging is instrumental in guiding diagnostic and therapeutic strategies when managing mPVLs. Advances in imaging and capabilities of transcather devices will prompt growing uptake of percutaneous treatment over conventional, higher-risk surgery for mPVL management.

Head to Head Comparison between Different 3-Dimensional Echocardiographic Rendering Tools in the Imaging of Percutaneous Edge-to-Edge Mitral Valve Repair

MitraClip (MC) is the most common percutaneous treatment for severe mitral regurgitation (MR). An accurate two-dimensional and three-dimensional echocardiographic (3DTEE) imaging is mandatory for the optimal procedural result. Recently transillumination 3DTEE rendering (3DTr) has been introduced integrating a virtual light source into the dataset and with the addition of glass effect (3DGl) allows to adjust tissue transparency improving depth perception and anatomical structure delineation in comparison with the standard 3DTEE (3DSt). The aim of this retrospective study in 30 patients undergoing MC, was to compare 3DSt, 3DTr, and 3DGl in mitral valve (MV) evaluation and procedural result assessment. 3DTEE acquisitions obtained before and after MC were processed with 3DSt, 3DTr, and 3DGl rendering. Each reconstruction was scored for quality and for ability to recognize MV anatomy, MR origin, clip position, dimension and grasping. Imaging quality was judged good or optimal in 52%, 76%, and 96% in 3DSt, 3DTr, and 3DGl reconstructions respectively. In 26/30 patients a diagnostic incremental value was found with 3DTr vs. 3DSt and in 15/26 with 3DGl vs. 3DTr and 3DSt. Only 3DGl with perpendicular cropping of the clip allowed to visualize and measure the grasped portion of each mitral leaflets. 3DTEE imaging during MC may be improved by 3DTr and 3DGl providing a better evaluation of MV, of leaflet grasping and of residual MR jets after MC.

Integration of three-dimensional echocardiography into the modern-day echo laboratory

Three-dimensional echocardiography (3DE) has emerged in recent decades from a conceptual, research tool to an important, useful imaging technique that can informatively impact daily clinical practice. However, its adoption into the modern-day echo laboratory requires the acknowledgment of its value, coupled with proper leadership, education, and resources to implement and integrate its use with conventional echo techniques. 3DE integration involves important updates regarding equipment and patient selection, assimilation of 3D protocols into current clinical routine, laboratory workflow adaptation, storage, and reporting. This review will provide a practical blueprint and key points of how to integrate 3DE into today's echo laboratory, necessary resources to implement 3D workflow, logistical challenges that remain, and future directions to further improve assimilation of this relevant echo technique into the laboratory.

A comprehensive review of the diagnosis and management of mitral paravalvular leakage

Mitral paravalvular leaks (PVLs) commonly occur in patients with prosthetic valves. Paravalvular defects may be clinically inconsequential and may aggravate hemolysis or cause heart failure through regurgitation. Accordingly, patients may eventually require intervention such as redo surgery or a transcatheter closure of the defects. The introduction of purpose-specific closure devices and new steerable catheters has opened a new frontier for the transcatheter PVL closure. This mode of treatment is an initial therapy in most centers with experienced structural heart team. However, head-to-head data comparing two treatment modalities (surgery and transcatheter closure) are limited, and the world-wide experience is based on nonrandomized studies. Multimodality imaging, including three-dimensional transesophageal echocardiography, facilitates the delineation of mitral PVLs and provides essential data that aids the communication between the members of the structural heart team. In the near future, the success of interventional therapies will most probably increase in patients with mitral PVLs with the introduction of hybrid imaging modalities (echocardiography, cardiac computed tomography, and fluoroscopy). In conclusion, this paper summarizes the etiopathogenesis, clinical characteristics, diagnosis, and treatment of mitral PVLs. (Anatol J Cardiol 2020; 24: 350-60)

Value of echocardiography for mini-invasive per-atrial closure of perimembranous ventricular septal defect

The purpose of this study was to assess the value of echocardiography for intraoperative guidance during closure of perimembranous ventricular septal defects (pmVSD) and to assess outcomes of these patients. We identified and assessed 78 patients who underwent 2- and 3-dimensional echocardiography-guided mini-invasive per-atrial closure of pmVSD in the cardiac surgery department of our institution, from February 2016 to August 2018, and 76 patients who underwent transcatheter closure of VSD guided by fluoroscopy at the pediatric department (percutaneous control group). All the patients underwent echocardiography. Their clinical data were retrospectively reviewed and analyzed. All patients were followed up using transthoracic echocardiography (TTE) for a maximum of 24 months after the closure. All patients underwent successful device implantation. Echocardiography showed that the major immediate complications included residual shunt, pericardial effusion, and tricuspid regurgitation in the per-atrial group. During the mid-term follow-up period, TTE revealed that the most common complication was tricuspid regurgitation (non-preexisting). There were no cases of VSD recurrence, device displacement, valvular injury, malignant arrhythmias, hemolysis, or death. Moreover, according to the TTE data, the intracardiac structure of the patients were improved. Compared to the control group, the intracardiac manipulation time was shorter and the number of patients with residual shunts, redeployment of devices, or immediate new tricuspid regurgitations was fewer when using 2- and 3-dimensional echocardiography. However, the procedure time in the per-atrial group was slightly longer than that in the control group. Two- and 3-dimensional echocardiography are feasible monitoring tools during mini-invasive per-atrial VSD closure. The short- and mid-term follow-up showed satisfactory results compared to fluoroscopy.

Applications of three-dimensional transesophageal echocardiography in congenital heart disease

Three-dimensional echocardiography allows for presurgical planning for congenital heart disease, reduces radiation using fusion imaging in catheter interventions, and provides guidance during catheter interventions and lead placements or extractions. The purpose of this review is to detail applications of three-dimensional transesophageal echocardiography in presurgical planning of congenital heart disease, guidance of catheter interventions such as fusion imaging, and guidance in electrophysiology lead extractions or placements.

Feasibility and accuracy of real-time three-dimensional echocardiography in evaluating the aortic valve in children

Background

Aortic valve assessment by 2D transthoracic echocardiography is a relatively complex task owing to the unique anatomical features of the left ventricular outflow tract and its dynamic nature. We aimed to evaluate the accuracy of 3D transthoracic echocardiography [3D TTE] in assessing the aortic valve in children.

Results

The first group included 11 males and six females, with a mean age of 5.76 ± 6.39 years. All of these patients had aortic valve disease with a bicuspid variant. The second group included seven males and seven females, with a mean age of 4.4 ± 4.05 years. All of these patients had normal aortic valve morphology and had another congenital cardiac anomaly. The aortic valve annulus was assessed using the three modalities; 2D, 3D echocardiography in the vertical and horizontal diameters, and angiography. The aortic valve area was measured by 2D and 3D echocardiography using multiplane reformatted mode. The results of the analysis were then compared. They revealed that 3D echocardiographic measurement of the aortic annulus (horizontal diameter) correlated better with angiography than 2D and 3D (vertical diameter) echocardiographic measurements. There was a significant difference between the aortic valve area measured by 2D echocardiography and that measured by 3D echocardiography among the two groups, 2D echocardiography seems to underestimate the true aortic valve area.

Conclusion

The study concluded that 3D TTE with multiplane reformatted mode allows a more accurate assessment of the aortic valve when compared to 2D echocardiography and this correlates better with the angiographic findings.

Percutaneous devices for left atrial appendage occlusion: A contemporary review

Patient with atrial fibrillation (AF) are at risk of developing stroke with the left atrial appendage (LAA) being the most common site for thrombus formation. If left untreated, AF is associated with 4 to 5 folds increase in the risk of ischemic stroke in all age groups. About 5% to 15% of AF patients have atrial thrombi on transesophageal echocardiography, and 91% of those thrombi are located in the LAA in patient with nonrheumatic AF. Although oral anticoagulants are the gold-standard treatment for stroke prevention in patients with non-valvular AF, some patients are at high risk of bleeding and deemed not candidates for anticoagulation. Therefore, LAA occlusion (LAAO) has emerged as alternative approach for stroke prevention in those patients. Surgical LAAO is associated with high rate of unsuccessful closure and recommended only in patients with AF and undergoing cardiac surgery. Percutaneous LAAO uses transvenous access with trans-septal puncture and was first tested using the PLAATO device. Watchman is the most common and only Food and Drug Administration (FDA) approved device for LAAO. LAAO using Watchman device is non-inferior to warfarin therapy in preventing ischemic stroke/systemic thromboembolism. However, it is associated with lower rates of hemorrhagic stroke, bleeding and death. Amplatzer is another successful LAAO device that has CE mark and is waiting for FDA approval. Optimal antithrombotic therapy post LAAO is still under debate and highly patient-specific. The aim of this paper is to systematically review the current literature to evaluate the efficacy and safety of different LAAO devices.

Role of real time-three dimensional transesophageal echocardiography in left atrial appendage closure with LACBES® devices

Catheter-based left atrial appendage closure (LAAC) has recently become an innovative strategy for preventing embolic events in patients with nonvalvular atrial fibrillation (AF). There is limited information on optimal sizing for LAAC with the recently developed LACBES^® device. The aim of the present study was to assess the role of real time-three dimensional transesophageal echocardiography (RT-3D TEE) for LACBES^® device selection during LAAC. A total of 22 patients with nonvalvular AF and indications for LAAC were enrolled in the study. All patients underwent LAAC with LACBES^® devices. TEE was performed in all patients 3 days prior to the procedure, during the procedure, and 3 months and 1 year following the procedure. Interatrial septal puncture, exchange of the sheath and release of the device were performed under the guidance of RT-3D TEE. The LAA ostium and landing zone dimensions measured by RT-3D TEE were better correlated with the device size used for occlusion (r=0.60, P=0.003) than those measured with two dimensional TEE or LAA contrast angiography. There were no clinically significant residual shunts, pericardial effusion or tamponade following occlusion. All patients had the device well-seated and presented no evidence of closure-associated complications during the follow-up. No cases of peri-procedural stroke or mortality were observed during a mean follow-up period of 12 months. In conclusion, RT-3D TEE is a reliable and effective imaging modality to guide LAAC using LACBES^® devices in patients with nonvalvular AF at high risk of cardioembolic events.

Strategy for Monitoring Cardiac Interventions with an Intelligent Robotic Ultrasound Device

In recent years, 3D trans-oesophageal echocardiography (TOE) has become widely used for monitoring cardiac interventions. The control of the TOE probe during the procedure is a manual task which is tedious and harmful for the operator when exposed to radiation. To improve this technique, an add-on robotic system has been developed for holding and manipulating a commercial TOE probe. This paper focuses on the probe adjustment strategy in order to accurately monitor the moving intra-operative catheters. The positioning strategy is divided into an initialization step based on a pre-planning method, and a localized adjustment step based on the robotic differential kinematics. A series of experiments was performed to evaluate the initialization and the localized adjustment steps. The results indicate a mean error less than 10 mm from the phantom experiments for the initialization step, and a median error less than 1.5 mm from the computer-based simulation experiments for the localized adjustment step. Compared to the much bigger image volume, it is concluded that the proposed methods are feasible for this application. Future work will focus on evaluating the method in a more realistic TOE scanning scenario.

Innovation in 3D Echocardiographic Imaging

PURPOSE OF REVIEW

The purpose of this review is to detail three-dimensional echocardiographic (3DE) innovations in pre-surgical planning of congenital heart disease, guidance of catheter interventions such as fusion imaging, and functional assessment of patients with congenital heart disease.

RECENT FINDINGS

Innovations in 3DE have helped us delineate the details of atrioventricular valve function and understand the mechanism of atrioventricular valve failure in patients with atrioventricular septal defect and single ventricle post repair. Advancement in holographic display of 3D datasets allows for better manipulation of 3D images in three dimensions and better understanding of anatomic relationships. 3DE with fusion imaging reduces radiation in catheter interventions and provides presentations of 3DE images in the similar fashion as the fluoroscopic images to improve communication between cardiologists. Lastly, 3DE allows for quantitative ventricular volumetric and functional assessment. Recent innovations in 3DE allow for pre-surgical planning for congenital heart disease, reduce radiation using fusion imaging in catheter interventions, and enable accurate assessment of ventricular volume and function without geometric assumptions.

3D and 4D Ultrasound: Current Progress and Future Perspectives

PURPOSE OF REVIEW

Three-dimensional (3D) echocardiography (3DE) and 4-dimensional echocardiography (4DE), also known as real-time (RT) 3DE (RT3DE), are rapidly emerging technologies which have made significant impact in the clinical arena over the years. This review will discuss the recent applications of 3DE in diagnosing and treating different types of cardiovascular disease.

RECENT FINDINGS

Recent studies using 3DE expanded on prior findings and introduced additional applications to different cardiac conditions. Some studies have used 3D parameters to prognosticate long-term outcomes. Numerous innovative software designs including fully automated algorithms have been introduced to better evaluate valvular heart disease and cardiac function.

SUMMARY

With further evolution of 3DE technologies, this imaging modality will emerge as a powerful tool and likely become the imaging modality of choice in the diagnosis and management of various cardiac disorders.

Role of 3D Echocardiography in Cardiac Surgery: Strengths and Limitations

PURPOSE OF REVIEW

This review aims to highlight the general and specific strengths and limitations of intraoperative 3D echocardiography. This article explains the value of real-time three-dimensional transesophageal echocardiography (RT 3D TEE) during cardiac surgery and cardiac interventions.

RECENT FINDINGS

Recently published recommendations and guidelines include the use of RT 3D TEE. RT 3 D TEE provides additional value particularly for guidance during cardiac interventions (i.e., transcatheter mitral valve repair, left atrial appendix and atrial septal defect closures), assessment of the mitral valve in surgical repair, measurement of left ventricular outflow tract area for transcatheter valvular replacements, and estimating right and left ventricular volumes and function. The exact localization of paravalvular leakage is another strength of RT 3D TEE. The major limitation is the reduced temporal resolution compared to 2D TEE.

SUMMARY

Three-dimensional echocardiography is a powerful tool that improves communication and accurate measurements of cardiac structures.

Three-dimensional echocardiography in adult congenital heart disease

Congenital heart disease (CHD) is now more common in adults than in children due to improvements in fetal echo, neonatal and pediatric care, and surgical techniques leading to dramatically increased survivability into adulthood. Adult patients with CHD, regardless of prior cardiac surgery, experience further cardiac problems or therapeutic challenges; therefore, a non-invasive, easily accessible echocardiographic examination is an essential follow-up tool. Among echocardiographic modalities, three-dimensional (3D) echocardiography provides better delineation of spatial relationships in complex cardiac geometries and more accurate volumetric information without geometric assumptions. For atrial septal defects, an en face view of the tissue defect allows better decisions on device closure. For tricuspid valve malformations, an en face view provides diagnostic information that is difficult to obtain from routine 2D tomography. In repaired tetralogy of fallot with pulmonary regurgitation, preoperative 3D echocardiography- based right ventricular volume may be used to determine the timing of a pulmonary valve replacement in conjunction with cardiovascular magnetic imaging. For optimal adult CHD care, 3D echocardiography is an important complement to routine 2D echocardiography.

Three-dimensional transesophageal echocardiography: Principles and clinical applications

A basic understanding of evolving 3D technology enables the echocardiographer to master the new skills necessary to acquire, manipulate, and interpret 3D datasets. Single button activation of specific 3D imaging modes for both TEE and transthoracic echocardiography (TTE) matrix array probes include (a) live, (b) zoom, (c) full volume (FV), and (d) color Doppler FV. Evaluation of regional LV wall motion by RT 3D TEE is based on a change in LV chamber subvolume over time from altered segmental myocardial contractility. Unlike standard 2D TEE, there is no direct measurement of myocardial thickening or displacement of individual segments.

Effects of postural change on transesophageal echocardiography views and parameters in healthy dogs

The purpose of the present study is to investigate the effect of postural change on transesophageal echocardiography (TEE) views and parameters of interest anesthesia monitoring in healthy dogs. Twelve Beagle dogs were anesthetized and randomly positioned in one of four postures: right lateral-recumbency, left lateral-recumbency, supine position and prone position. After examinations in one posture, the same examination was demonstrated in another posture and repeated in all postures. In each posture, several standard TEE views were demonstrated: longitudinal cranial-esophageal aorta long-axis-view, transverse middle-esophageal mitral valve long-axis-view and transgastric middle short-axis-view. Additionally, echocardiographic parameters were attempted to measure, and direct blood pressure monitoring was performed in each view. As a result, oriented views, except for transgastric middle short-axis-view, could be obtained in all postures. Stroke volume and peak early diastolic velocity of mitral inflow were lower in supine position compared with those in right and left lateral-recumbency. Heart rate (HR) and systemic vascular resistance were higher in supine position compared with those in right and left lateral-recumbency. Left ventricular pre-ejection period/left ventricular ejection time corrected and uncorrected by HR were higher in supine position compared with those in right and left lateral-recumbency. In conclusion, longitudinal cranial-esophageal aorta long-axis-view and transverse middle-esophageal mitral valve long-axis-view provide useful information of interest anesthesia monitoring, because of their views enable to certainly obtain TEE parameters in various postures. Furthermore, TEE parameters allow to detect the changes of preload, afterload and HR that occur in supine position dogs.

Roles of real-time three-dimensional transesophageal echocardiography in peri-operation of transcatheter left atrial appendage closure

Left atrial appendage (LAA) closure is a new treatment option for the prevention of stroke in patients with nonvalvular atrial fibrillation (AF). Conventional 2-dimensional transesophageal echocardiography (2D TEE) has some limitations in the imaging assessment of LAA closure. Real-time 3-dimensional transesophageal echocardiography (RT-3D TEE) allows for detailed morphologic assessment of the LAA. In this study, we aim to determine the clinical values of RT-3D TEE in the periprocedure of LAA closure.Thirty-eight persistent or paroxysmal AF patients with indications for LAA closure were enrolled in this study. RT-3D TEE full volume data of the LAA were recorded before operation to evaluate the anatomic feature, the landing zone dimension, and the depth of the LAA. On this basis, selection of LAA closure device was carried out. During the procedure, RT-3D TEE was applied to guide the interatrial septal puncture, device operation, and evaluate the occlusion effects. The patients were follow-up 1 month and 3 months postclosure.Twenty-eight (73.7%) patients with AF received placement of LAA occlusion device under RT-3D TEE. Eleven cases with single-lobe LAAs were identified using RT-3D TEE, among which 4 showed limited depth. Seventeen cases showed bilobed or multilobed LAA. Seven cases received LAA closure using Lefort and 21 using LAmbre based on the 3D TEE and radiography. The landing zone dimension of the LAA measured by RT-3D TEE Flexi Slice mode was better correlated with the device size used for occlusion (r = 0.90) than 2D TEE (r = 0.88). The interatial septal puncture, the exchange of the sheath, as well as the release of the device were executed under the guidance of RT-3D TEE during the procedure. The average number of closure devices utilized for optimal plugging was (1.11 ± 0.31). There were no clinically unacceptable residual shunts, pericardial effusion, or tamponade right after occlusion. All the patients had the device well-seated and no evidence of closure related complications in the follow-up.Assessment of LAA morphology by RT-3D TEE contributes to the decision of device selection for the closure. 3D TEE is a reliable imaging modality to guide device operation and assess on-site closure.

4-D ICE: A 2-D Array Transducer With Integrated ASIC in a 10-Fr Catheter for Real-Time 3-D Intracardiac Echocardiography

We developed a 2.5 ×6.6 mm ² 2 -D array transducer with integrated transmit/receive application-specific integrated circuit (ASIC) for real-time 3-D intracardiac echocardiography (4-D ICE) applications. The ASIC and transducer design were optimized so that the high-voltage transmit, low-voltage time-gain control and preamp, subaperture beamformer, and digital control circuits for each transducer element all fit within the 0.019-mm ² area of the element. The transducer assembly was deployed in a 10-Fr (3.3-mm diameter) catheter, integrated with a GE Vivid E9 ultrasound imaging system, and evaluated in three preclinical studies. The 2-D image quality and imaging modes were comparable to commercial 2-D ICE catheters. The 4-D field of view was at least 90 ^° ×60 ^° ×8 cm and could be imaged at 30 vol/s, sufficient to visualize cardiac anatomy and other diagnostic and therapy catheters. 4-D ICE should significantly reduce X-ray fluoroscopy use and dose during electrophysiology ablation procedures. 4-D ICE may be able to replace transesophageal echocardiography (TEE), and the associated risks and costs of general anesthesia, for guidance of some structural heart procedures.

Feasibility and Safety of Using a Fused Echocardiography/Fluoroscopy Imaging System in Patients with Congenital Heart Disease

BACKGROUND

Fused real-time three-dimensional transesophageal echocardiography and fluoroscopy has been used in adult patients during percutaneous mitral valve and aortic valve procedures. The use of fused echocardiographic/x-ray fluoroscopic imaging (FEX) in pediatric patients undergoing congenital heart disease catheterization has not been evaluated for feasibility and safety. The aims of this study were to assess the feasibility and safety of FEX for interventional guidance and to perform a comparison of atrial septal defect (ASD) device closure using this technology with traditional guidance methods.

METHODS

Prospective evaluation of FEX in congenital cardiac interventions was conducted. A subset of patients with ASD closures were compared with patients with historical ASD closures with and without FEX. The interventionalist and echocardiographer rated the anatomic quality of the fusion imaging as (1) excellent, (2) good, or (3) poor. In addition, the utility of FEX procedural guidance was graded as (1) superior, (2) no added benefit, or (3) inferior to that of standard guidance by fluoroscopy and transesophageal echocardiography.

RESULTS

FEX was successfully used in 26 procedures on 25 patients with congenital heart disease from January 2013 to February 2015. The median age was 9 years (range, 3-26 years), and the median weight was 29 kg (range, 16-77 kg). Twenty-six procedures were performed, including ASD closure, Fontan fenestration closure, and transcatheter valve placement in the tricuspid valve position. There was reduced fluoroscopy time and radiation dose in patients with ASDs who underwent imaging using this new technology (P < .001 and P < .03, respectively). There were no statistically significant differences in procedural times between the two groups. Anatomic definition was rated as excellent in 20 of 26 procedures, with the remaining six rated was good. Twenty-one of 26 procedures were graded as superior (81%), and five of 26 (19%) were graded as providing no added benefit. There were no complications in any of the procedures.

CONCLUSIONS

In this early experience, FEX is feasible and safe in patients undergoing congenital heart disease catheterization and provides useful guidance in the majority of interventional procedures. There were relative reductions in fluoroscopy time and radiation dose with the use of FEX for ASD closure.

Echogenic mobile images in intraprocedural three-dimensional transesophageal echocardiographic monitoring during percutaneous aortic valve implantation: Incidence, characteristics and clinical implications

INTRODUCTION AND OBJECTIVES

To investigate the incidence and clinical relevance of the presence of mobile echogenic images (MEI) during transesophageal echocardiography (TEE) for monitoring of transcatheter aortic valve implantation (TAVI).

METHODS

Consecutive patients referred to our center for transfemoral or transapical TAVI were included. The procedure was monitored by three-dimensional (3D) TEE and images were analyzed by two independent experts. In-hospital follow-up was carried out and correlated with imaging findings.

RESULTS

A total of 104 patients were included. MEI were visualized in 11 patients during the procedure (11%) and in over 50% of cases were identified as thrombi, however no differences in periprocedural stroke were found in follow-up.

CONCLUSIONS

Visualization of MEI during 3D TEE monitoring of TAVI is relatively common (11%) and in over 50% of cases they are identified as thrombi. The clinical implications of this finding are uncertain, as despite their frequency, the incidence of clinical stroke in this patient population was no higher. 3D TEE is a useful tool for diagnosis of MEI and can alert the operator to their presence.

Utility of Real-Time 3-Dimensional Transesophageal Echocardiography in the Assessment of Mitral Paravalvular Leak

BACKGROUND

Mitral paravalvular leak (PVL) is a potential complication of surgical valve replacement procedures. Real-time 3D transesophageal echocardiography (RT-3DTEE) has emerged as an efficient tool for providing essential information about the anatomy of mitral PVLs compared with 2DTEE findings. The purpose of this study was to evaluate the utility of RT-3DTEE in the assessment of mitral PVLs.

METHODS AND RESULTS

The 3D characteristics of PVLs were recorded and compared with 2D findings. We included 34 consecutive patients with clinical suspicion of mitral PVL in the study. Mitral PVLs were detected in 26 patients (76%); 26 PVLs were identified by 2DTEE and 37 by RT-3DTEE. Moderate or severe mitral regurgitation was present in 23 patients (88%). The most common PVL locations were the septal and posterior regions. The median PVL size measured by RT-3DTEE was 7 mm long×4 mm wide. The median vena contracta of defect measured by 2DTEE and RT-3DTEE was 5 mm and 4 mm, respectively. The median effective regurgitant orifice area of defect measured by RT-3DTEE was 0.36 cm(2). The defect types were "oval" (54%), "round" (35%), "crescentic" (8%) and highly irregular (3%).

CONCLUSIONS

Compared with 2DTEE, RT-3DTEE provided detailed descriptions of the number, location, size and morphology of PVLs, which is essential for planning and guiding the potential corrective techniques. (Circ J 2016; 80: 738-744).

Percutaneous interventions for left atrial appendage exclusion: options, assessment, and imaging using 2D and 3D echocardiography

Percutaneous left atrial appendage (LAA) exclusion is an evolving treatment to prevent embolic events in patients with nonvalvular atrial fibrillation. In the past few years multiple percutaneous devices have been developed to exclude the LAA from the body of the left atrium and thus from the systemic circulation. Two- and 3-dimensional transesophageal echocardiography (TEE) is used to assess the LAA anatomy and its suitability for percutaneous closure to select the type and size of the closure device and to guide the device implantation procedure in conjunction with fluoroscopy. In addition, 2- and 3-dimensional TEE is also used to assess the effectiveness of device implantation acutely and on subsequent follow-up examination. Knowledge of the implantation options that are currently available along with their specific characteristics is essential for choosing the appropriate device for a given patient with a specific LAA anatomy. We present the currently available LAA exclusion devices and the echocardiographic imaging approaches for evaluation of the LAA before, during, and after LAA occlusion.

Three-dimensional transesophageal echocardiography in degenerative mitral regurgitation

The morphology of mitral valve (MV) prolapse and flail may be extremely variable, with dominant and secondary dynamic lesions. Any pathologic valve appears unique and different from any other. Three-dimensional (3D) transesophageal echocardiography is a powerful tool to evaluate the geometry, dynamics, and function of the MV apparatus and may be of enormous value in helping surgeons perform valve repair procedures. Indeed, in contrast to the surgical view, 3D transesophageal echocardiography can visualize MV prolapse and flail in motion and from different perspectives. The purpose of this special article is not to provide a comprehensive review of degenerative MV disease but rather to illustrate different types of mitral prolapse and flail as they appear from multiple 3D transesophageal echocardiographic perspectives using a series of clinical scenarios. Because in everyday practice, 3D transesophageal echocardiographic images of MV prolapse and flail are usually observed in motion, each scenario is accompanied by several videos. Finally, the authors provide for each scenario a brief description of the surgical techniques that are usually performed at their institution.

3D TEE during catheter-based interventions

Guidance of catheter-based procedures is performed using fluoroscopy and 2-dimensional transesophageal echocardiography (TEE). Both of these imaging modalities have significant limitations. Because of its 3-dimensional (3D) nature, 3D TEE allows visualizing the entire scenario in which catheter-based procedures take place (including long segments of catheters, tips, and the devices) in a single 3D view. Despite these undeniable advantages, 3D TEE has not yet gained wide acceptance among most interventional cardiologists and echocardiographists. One reason for this reluctance is probably the absence of standardized approaches for obtaining 3D perspectives that provide the most comprehensive information for any single step of any specific procedure. Therefore, the purpose of this review is to describe what we believe to be the most useful 3D perspectives in the following catheter-based percutaneous interventions: transseptal puncture; patent foramen ovale/atrial septal defect closure; left atrial appendage occlusion; mitral valve repair; and closure of paravalvular leaks.

Clinical application of three-dimensional echocardiography

Echocardiography is one of the most valuable diagnostic tools in cardiology. Technological advances in ultrasound, computer and electronics enables three-dimensional (3-D) imaging to be a clinically viable modality which has significant impact on diagnosis, management and interventional procedures. Since the inception of 3D fully-sampled matrix transthoracic and transesophageal technology it has enabled easier acquisition, immediate on-line display, and availability of on-line analysis for the left ventricle, right ventricle and mitral valve. The use of 3D TTE has mainly focused on mitral valve disease, left and right ventricular volume and functional analysis. As structural heart disease procedures become more prevalent, 3D TEE has become a requirement for preparation of the procedure, intra-procedural guidance as well as monitoring for complications and device function. We anticipate that there will be further software development, improvement in image quality and workflow.

Role of Transesophageal Echocardiography in Left Atrial Appendage Device Closure

Left atrial appendage (LAA) occlusion or ligation by percutaneously implanted devices is increasingly an alternative management option for atrial fibrillation, particularly for patients who are intolerant or have contraindications for anticoagulation. Echocardiography plays an important part in screening, guidance of implantation, and after-device assessment. Assessment of LAA anatomy suitable for device implantation, thrombus exclusion, guidance of transseptal puncture, localization of catheter, guidance of device deployment, and after-device assessment are all important functions of echocardiography. This article reviews the role of echocardiography in device-based LAA occlusion or ligation.

Acoustic radiation force impulse imaging (ARFI) on an IVUS circular array

Our long-term goal is the detection and characterization of vulnerable plaque in the coronary arteries of the heart using intravascular ultrasound (IVUS) catheters. Vulnerable plaque, characterized by a thin fibrous cap and a soft, lipid-rich necrotic core is a precursor to heart attack and stroke. Early detection of such plaques may potentially alter the course of treatment of the patient to prevent ischemic events. We have previously described the characterization of carotid plaques using external linear arrays operating at 9 MHz. In addition, we previously modified circular array IVUS catheters by short-circuiting several neighboring elements to produce fixed beamwidths for intravascular hyperthermia applications. In this paper, we modified Volcano Visions 8.2 French, 9 MHz catheters and Volcano Platinum 3.5 French, 20 MHz catheters by short-circuiting portions of the array for acoustic radiation force impulse imaging (ARFI) applications. The catheters had an effective transmit aperture size of 2 mm and 1.5 mm, respectively. The catheters were connected to a Verasonics scanner and driven with pushing pulses of 180 V p-p to acquire ARFI data from a soft gel phantom with a Young's modulus of 2.9 kPa. The dynamic response of the tissue-mimicking material demonstrates a typical ARFI motion of 1 to 2 microns as the gel phantom displaces away and recovers back to its normal position. The hardware modifications applied to our IVUS catheters mimic potential beamforming modifications that could be implemented on IVUS scanners. Our results demonstrate that the generation of radiation force from IVUS catheters and the development of intravascular ARFI may be feasible.

Artifacts in three-dimensional transesophageal echocardiography

Three-dimensional (3D) transesophageal echocardiography (TEE) is subject to the same types of artifacts encountered on two-dimensional TEE. However, when displayed in a 3D format, some of the artifacts appear more "realistic," whereas others are unique to image acquisition and postprocessing. Three-dimensional TEE is increasingly used in the setting of percutaneous catheter-based interventions and ablation procedures, and 3D artifacts caused by the metallic components of catheters and devices are particularly frequent. Knowledge of these artifacts is of paramount relevance to avoid misinterpretation of 3D images. Although artifacts and pitfalls on two-dimensional echocardiography are well described and classified, a systematic description of artifacts in 3D transesophageal echocardiographic images and how they affect 3D imaging is still absent. The aim of this review is to describe the most relevant artifacts on 3D TEE, with particular emphasis on those occurring during percutaneous interventions for structural heart disease and ablation procedures.

Transoesophageal echocardiography in the dog

Transoesophageal echocardiography (TEE) allows imaging of the heart through the oesophagus using a special transducer mounted on a modified endoscope. The proximity to the heart and minimal intervening structures enables the acquisition of high-resolution images that are consistently superior to routine transthoracic echocardiography and optimal imaging of the heart base anatomy and related structures. TEE provides high-quality real-time imaging free of ionizing radiation, making it an ideal instrument not only for diagnostic purposes, but also for monitoring surgical or minimally invasive cardiac procedures, non-cardiac procedures and critical cases in the intensive care unit. In human medicine, TEE is routinely used in these settings. In veterinary medicine, TEE is increasingly used in referral centres, especially for perioperative assessment and guidance of catheter-based cardiovascular procedures, such as patent ductus arteriosus, balloon valvuloplasty, and atrial and ventricular septal defect occlusion with vascular devices. TEE can also aid in heartworm retrieval procedures. The purpose of this paper is to review the current uses of TEE in veterinary medicine, focusing on technique, indications and complications.

[Echocardiography during transcatheter interventions. New developments]

Interventional techniques for percutaneous treatment of structural heart disease have become an important option for patients ineligible for conventional operating procedures in cardiovascular medicine. Echocardiography plays an essential role not only for patient selection but also for guiding transcatheter interventions in order to safely accomplish the procedure. Echocardiographic 2D and 3D techniques next to conventional fluoroscopy have therefore become an integral part for monitoring interventional procedures in the catheter laboratory. This review aims to describe new developments for the application of echocardiography during transcatheter interventions in the context of the current literature and current recommendations.

Can we talk? Reflections on effective communication between imager and interventionalist in congenital heart disease

The rapid proliferation of catheter-mediated treatments for congenital heart defects has brought with it a critical need for cooperation and communication among the numerous physicians supporting these new and complex procedures. New interdependencies between physicians in specialties including cardiac imaging, interventional cardiology, pediatric cardiology, anesthesia, cardiothoracic surgery, and radiology have become apparent, as centers have strived to develop the best systems to foster success. Best practices for congenital heart disease interventions mandate confident and timely input from an individual with excellent adjunctive imaging skills and a thorough understanding of the devices and procedures being used. The imager and interventionalist must share an understanding of what each offers for the procedure, use a common terminology and spatial orientation system, and convey concise and accurate information about what is needed, what is seen, and what cannot be seen. The goal of this article is to review how the cardiovascular imaging specialists and interventionalists can work together effectively to plan and execute catheter interventions for congenital heart disease.

Clinical advantage of real-time three-dimensional transesophageal echocardiography for transcatheter closure of multiple atrial septal defects

This study sought to evaluate the usefulness of real-time three-dimensional (3D) transesophageal echocardiography (TEE) to guide the repair of multiple atrial septal defects (ASDs). Of 212 consecutive patients with secundum ASD who were scheduled for transcatheter closure of their ASDs, 27 had multiple ASDs. These patients underwent two-dimensional (2D) transthoracic echocardiography, 2D TEE, and 3D TEE. Overall, 18 patients had two defects, and 9 patients had three or more defects. The latter group included three patients with multi-fenestrated defects. Optimal 3D images were obtained in 93 % of the patients. In patients with two defects, information on the positional relation of the defects was obtained using 2D TEE and 3D TEE in 71 and 94 % of patients, respectively (P = 0.22). The positional relations of the defects could not be evaluated with 2D TEE in patients with three or more defects, whereas it could be evaluated with 3D TEE in all of these patients (0 vs. 100 %, P = 0.008). In all patients, 3D TEE proved superior to 2D TEE for providing sufficient information (96 vs. 48 %, P = 0.002). Procedural success was obtained in 26 patients (96.3 %), without complications. Transcatheter closure of multiple ASDs under 3D TEE guidance is effective and safe. Real-time 3D TEE can provide useful information regarding complex ASD morphology. It can thus contribute to developing a successful treatment strategy, especially in patients with three or more defects.