Live 3-Dimensional Transesophageal Echocardiography

Transesophageal echocardiography: A bibliometric analysis from 1979 to 2022

OBJECTIVE

Heart disease poses a significant global health challenge. Transesophageal echocardiography (TEE) has gained prominence in clinical practice because of advancements in visual medicine. The present bibliometric analysis provides an overview of TEE research, identifies trends, and highlights emerging topics.

METHODS

A comprehensive search of TEE-related literature from the establishment of the Web of Science Core Collection (WOSCC) until 2022 was conducted. Utilizing the CiteSpace software, we performed an in-depth analysis of the literature data encompassing disciplines, publication years, countries, institutions, authors, journals, cited references, and keywords.

RESULTS

A total of 17 032 TEE-related articles were included in this study. The most active disciplines in TEE research were Cardiac & Cardiovascular Systems, Anesthesiology, and Respiratory System. The number of publications displayed a consistent upward trajectory over the years. Notably, research contributions predominantly originated from developed countries, mainly Europe and North America, with the United States, Germany, Italy, and Japan leading the way. Analysis of institutions, authors, and journals revealed the United States' significant role in TEE research. Furthermore, the analysis of cited references and keywords identified the treatment of patent foramen ovale and its association with stroke as emerging hot topics in recent years.

CONCLUSIONS

This study highlights that TEE remains a research hotspot, with the United States at the forefront. Future research should investigate the relationship between heart disease and brain function.

Three-dimensional transoesophageal echocardiography: how to use and when to use-a clinical consensus statement from the European Association of Cardiovascular Imaging of the European Society of Cardiology

Three-dimensional transoesophageal echocardiography (3D TOE) has been rapidly developed in the last 15 years. Currently, 3D TOE is particularly useful as an additional imaging modality for the cardiac echocardiographers in the echo-lab, for cardiac interventionalists as a tool to guide complex catheter-based procedures cardiac, for surgeons to plan surgical strategies, and for cardiac anaesthesiologists and/or cardiologists, to assess intra-operative results. The authors of this document believe that acquiring 3D data set should become a 'standard part' of the TOE examination. This document provides (i) a basic understanding of the physic of 3D TOE technology which enables the echocardiographer to obtain new skills necessary to acquire, manipulate, and interpret 3D data sets, (ii) a description of valvular pathologies, and (iii) a description of non-valvular pathologies in which 3D TOE has shown to be a diagnostic tool particularly valuable. This document has a new format: instead of figures randomly positioned through the text, it has been organized in tables which include figures. We believe that this arrangement makes easier the lecture by clinical cardiologists and practising echocardiographers.

Transcatheter tricuspid valve intervention: to repair or to replace?

PURPOSE OF REVIEW

The burden of tricuspid regurgitation (TR) is high in the aging population, almost 4% in the age group over 75 have moderate or more TR. This carries a poor prognosis and an increased incidence of mortality, prolonged hospitalization, and rehospitalization in symptomatic patients with severe TR is observed. Percutaneous tricuspid valve intervention has emerged as a viable therapeutic option, with an increasingly large toolbox of both tricuspid repair and replacement devices. The optimal strategy, timing and patient selection for transcatheter intervention are yet to be determined. This review focuses on the current strengths and limitations of transcatheter tricuspid repair vs. replacement, drawing on lessons learned from surgery.

RECENT FINDINGS

Early outcome studies have been published in the last 2 years for many of the new percutaneous tricuspid valve devices. We have summarized these results and compared them to surgical tricuspid valve repair and replacement. We found that surgical data shows a tendency to better outcome with tricuspid valve repair compared to replacement. For transcatheter interventions studies comparing repair and replacement are lacking but both interventions show good procedural success rates and are efficient in reducing the grade of tricuspid regurgitation.

SUMMARY

Transcatheter tricuspid valve interventions offer a safe and effective alternative to tricuspid surgery or medical therapy. The decision between valve replacement and repair should be based on patient anatomy, operator experience and device availability until head-to-head comparison of different devices are available.

A concise history of echocardiography: timeline, pioneers, and landmark publications

Echocardiography is less than 70 years old, and many major advances have occurred within living memory, but already some pioneering contributions may be overlooked. In order to consider what circumstances have been common to the most successful innovations, we have studied and here provide a timeline and summary of the most important developments in transthoracic and transoesophageal ultrasound imaging and Doppler techniques, as well as in intravascular ultrasound and imaging in paediatric cardiology. The entries are linked to a comprehensive list of first publications and to a collection of first-hand historical accounts published by early investigators. Review of the original manuscripts highlights that it is difficult to establish unequivocal precedence for many new imaging methods, since engineers were often working independently but simultaneously on similar problems. Many individuals who are prominently linked with particular developments were not the first in their field. Developments in echocardiography have been highly dependent on technological advances, and most likely to be successful when engineers and clinicians were able to collaborate with open exchange between centres and disciplines. As with many other new medical technologies, initial responses were sceptical and introduction into clinical practice required persistence and substantial energy from the first adopters. Current developments involve advances in software as much as in equipment, and progress will depend on continuing collaborations between engineers and clinical scientists, for example to identify unmet needs and to investigate the clinical impact of particular imaging approaches.

[Rheumatic mitral aggression. Usefulness of 3d transesophageal echocardiography]

Rheumatic heart disease is the leading cause of cardiovascular disease in children under 25 years of age worldwide, with the highest prevalence in low-income countries. The usual and distinctive finding of rheumatic aggression is mitral stenosis, which leads to serious cardiovascular consequences. International guidelines establish transthoracic echocardiography (TTE) as the diagnostic test for rheumatic heart disease; however, it has limitations in the measurement of planimetry and those inherent to Doppler. Transesophageal 3D echocardiography (TTE-3D) is a new modality that shows realistic images of the mitral valve and has the added value of accurately locating the plane of maximum stenosis and better determining commissural involvement.

Role of 3D Transesophageal Echocardiography for Transcatheter Mitral Valve Repair—A Mini Review

Edge-to-edge transcatheter mitral valve repair (TMVr) using MitraClip has been evolving rapidly in patients with severe mitral regurgitation (MR) at high surgical risk or having contraindications for surgery. Three-dimensional (3D) echocardiography plays an important role in the management of severe MR. In particular, 3D transesophageal echocardiography (TEE) imaging allows the evaluation of MV geometry and quantification of MR severity with dedicated software. Real-time 3D TEE is also commonly used to guide TMVr and facilitate the procedure. Further development of 3D echocardiography may help achieve safer and more beneficial results. The following article summarizes the current knowledge and the future perspectives of 3D TEE in TMVr.

The Role of Intracardiac Echocardiography in Percutaneous Tricuspid Intervention: A New ICE Age

The prevalence of severe tricuspid regurgitation in older patients is high, and the clinical relevance is perceived more and more in recent years. Many of these patients are not suitable for surgery because of their age and comorbidities. Therefore, a variety of percutaneous interventions have been developed to address this unmet need. Procedural success strongly depends on adequate imaging during the intervention. Although transesophageal echocardiography is the standard of care, imaging may be limited due to anatomic factors and adverse acoustic shadowing. In this review, we discuss the current and future role of intracardiac echocardiography in tricuspid valve interventions.

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.

Analysis of mitral valve morphology in dogs undergoing mitral valve repair with three-dimensional transesophageal echocardiography

INTRODUCTION

Information about real-time three-dimensional (3D) transesophageal echocardiography (TEE) for the evaluation of canine mitral valve morphology is lacking in veterinary medicine.

OBJECTIVES

To evaluate the feasibility of 3D TEE for the evaluation of canine mitral valves and whether there was a difference in mitral valve morphology between American College of Veterinary Internal Medicine (ACVIM) stages.

ANIMALS

Thirty-one dogs were evaluated, including nine dogs classified as ACVIM stage B2, 15 as stage C, and seven as stage D.

MATERIALS AND METHODS

Three-dimensional TEE was performed after anesthetic induction for mitral valve surgery, and the 3D geometry of the mitral valve apparatus was measured.

RESULTS

The intraclass correlation coefficient was good in both inter- and intraobserver analyses of the 3D measurements of mitral valve annulus geometry and excellent in both inter- and intraobserver analyses in the 3D measurements of mitral valve annular and leaflet sizes. Annulus height to commissural width ratio of stage D dogs showed significantly lower values than B2 dogs (B2: 14.2% [9.1-20.5%]; C: 10.6% [6.5-24.1%]; D: 9.5% [4.7-13.8%]). The aortic-mitral angle of stages C and D were significantly flatter than stage B2 (B2: 122.32 ± 9.39; C: 133.66 ± 8.43; D: 140.70 ± 10.70).

CONCLUSIONS

Real-time 3D echocardiography using TEE is a feasible method to evaluate the morphology of the mitral valve in dogs. The saddle shape of the mitral annulus and aortic-mitral angle were flatter in stage D. Further studies are required to understand the pathology of mitral valve disease in dogs.

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.

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.

Temporal Views of Flattened Mitral Valve Geometries

The mitral valve, one of the four valves in the human heart, controls the bloodflow between the left atrium and ventricle and may suffer from various pathologies. Malfunctioning valves can be treated by reconstructive surgeries, which have to be carefully planned and evaluated. While current research focuses on the modeling and segmentation of the valve, we base our work on existing segmentations of patient-specific mitral valves, that are also time-resolved ( 3D+t) over the cardiac cycle. The interpretation of the data can be ambiguous, due to the complex surface of the valve and multiple time steps. We therefore propose a software prototype to analyze such 3D+t data, by extracting pathophysiological parameters and presenting them via dimensionally reduced visualizations. For this, we rely on an existing algorithm to unroll the convoluted valve surface towards a flattened 2D representation. In this paper, we show that the 3D+t data can be transferred to 3D or 2D representations in a way that allows the domain expert to faithfully grasp important aspects of the cardiac cycle. In this course, we not only consider common pathophysiological parameters, but also introduce new observations that are derived from landmarks within the segmentation model. Our analysis techniques were developed in collaboration with domain experts and a survey showed that the insights have the potential to support mitral valve diagnosis and the comparison of the pre- and post-operative condition of a patient.

The Ideal Cardiac Mapping System

Cardiac mapping has witnessed significant and unprecedented progress over more than a century. At present, several mapping/imaging technologies are commercially available, alone or in combination. This article briefly discusses the advantages and limitations (disadvantages) of each technique.

Role of Intraoperative Transesophageal Echocardiography in Cardiac Surgery: an Observational Study

AIM:

This study is based on the hypothesis that the routine use of transesophageal echocardiography in cardiac surgery will influence the surgical decision taken by the surgeon intra-operatively in Kasr-Alainy hospitals.

METHODS:

Patients were examined with intraoperative transesophageal echocardiography (TEE) before and after cardiopulmonary bypass. Complete and comprehensive intraoperative TEE examinations will be performed by TEE certified cardiac anesthesiologists. Data that will be collected from the intraoperative examination and will be compared with preoperative transthoracic echocardiography, and the surgical decision that was taken preoperatively will be revised again with the cardiothoracic surgeon before the start of surgery. Also, TEE will be used again after weaning from bypass for revision and assessment of our decision.

RESULTS:

We examined the utility of TEE in 100 patients undergoing different types of cardiac procedures in Kasr Al-Ainy hospital. This prospective clinical investigation found that the pre- and post-CPB TEE examinations influenced surgical decision making in 10% of all evaluated patients.

CONCLUSION:

Intraoperative TEE has the potential to influence clinical decision making for cardiac surgical patients significantly. It is useful in surgical planning, guiding various hemodynamic interventions, and assessing the immediate results of surgery. Thus, IOTEE should be used routinely in all patients undergoing all types of cardiac surgeries.

Level of agreement in three-dimensional planimetric measurement of mitral valve area between transthoracic and transesophageal echocardiography

BACKGROUND

Echocardiographic measurement of mitral valve area (MVA) is critical prior to percutaneous transmitral commissurotomy (PTMC). This study aimed to compare the agreement between transthoracic (TTE) and transesophageal echocardiography (TEE) in three-dimensional (3D) planimetric measurement of the MVA among patients with severe mitral stenosis.

METHODS

MVA was measured with planimetry in 105 patients before undergoing PTMC. 3D reconstruction was applied to both TTE and TEE examinations. The MVA values from four different methods of 3D reconstruction were compared to the average values of 3D methods in TEE as the gold standard measurement method for the MVA in this study. The agreement levels between the two examinations were evaluated and analyzed for various reconstruction methods.

RESULTS

The mean age was 49 ± 12 years for 28 men and 77 women who were enrolled. The image quality was graded as "excellent" in 57% of 3D images obtained by TTE, while it was graded as "excellent" in 81% of 3D images obtained by TEE. The ventricular zooming method in TTE with a bias of -0.006 ± 0.065 cm² (P < 0.0001) had the highest agreement with the 3D-MVA in TEE. While 2D-TTE and 3D-TEE measurements of the MVA (R = 0.91; P < 0.0001) were significantly correlated, 2D-TTE overestimated the MVA by 0.19 cm² .

CONCLUSION

Although the quality of 3D images was significantly better in TEE than those in TTE, a good agreement existed between the measured 3D-TTE and 3D-TEE studies. We also demonstrated that 2D-TTE overestimated the MVA compare to 3D-TEE.

Simultaneous transmission and reception on all elements of an array: binary code excitation

Pulse-echo arrays are used in radar, sonar, seismic, medical and non-destructive evaluation. There is a trend to produce arrays with an ever-increasing number of elements. This trend presents two major challenges: (i) often the size of the elements is reduced resulting in a lower signal-to-noise ratio (SNR) and (ii) the time required to record all of the signals that correspond to every transmit-receive path increases. Coded sequences with good autocorrelation properties can increase the SNR while orthogonal sets can be used to simultaneously acquire all of the signals that correspond to every transmit-receive path. However, a central problem of conventional coded sequences is that they cannot achieve good autocorrelation and orthogonality properties simultaneously due to their length being limited by the location of the closest reflectors. In this paper, a solution to this problem is presented by using coded sequences that have receive intervals. The proposed approach can be more than one order of magnitude faster than conventional methods. In addition, binary excitation and quantization can be employed, which reduces the data throughput by roughly an order of magnitude and allows for higher sampling rates. While this concept is generally applicable to any field, a 16-element system was built to experimentally demonstrate this principle for the first time using a conventional medical ultrasound probe.

Three Dimensional (3D) Echocardiography as a Tool of Left Ventricular Assessment in Children with Dilated Cardiomyopathy: Comparison to Cardiac MRI

BACKGROUND:

Left ventricular (LV) volumes and ejection fraction (EF) is Strong prognostic indicators for DCM. Cardiac MRI (CMRI) is a preferred technique for LV volumes and EF assessment due to high spatial resolution and complete volumetric datasets. Three-dimensional echocardiography is a promising new technique under investigations.

AIM:

Evaluate 3D echocardiography as a tool in LV assessment in DCM children about CMRI.

PATIENTS AND METHODS:

A group of 20 DCM children (LVdiastolic diameter < 2 Z score, LVEF < 35%) at Children s Hospital, Ain-Shams University (gp1) (mean age 6.6 years) were compared to 20 age and sex-matched children as controls (gp2). Patients were subjected to: clinical examination, conventional echocardiography, automated 3D LV quantification, 3D speckle tracking echocardiography (3D-STE) (VIVID E9 Vingmed, Norway) and CMRI (Philips Achieva Nova, 1.5 Tesla scanner) for LV end systolic volume (LVESV), LVend diastolic volume (LVEDV) that were indexed to body surface area, EF% and wall motion abnormalities assessment.

RESUTS:

No statistically significant difference was found between automated 3D LV quantification echocardiography, 3D-STE, and CMRI in ESV/BSA and EDV/BSA assessment (p = 1, 0.99 respectively), between automated LV quantification echocardiography and CMRI in EF% assessment (p = 0.99) and between CMRI and 3D-STE in LV Global hypokinesia detection (P = 0.255). As for segmental hypokinesia CMRI was more sensitive [45% of patients vs. 40%, (P = 0,036), basal septal hypokinesia 85% vs. 75%, (p = 0.045), mid septal hypokinesia 80% vs. 65%, (p = 0.012) and lateral wall hypokinesia 75% vs. 65%, (p = 0.028)].

CONCLUSION:

Automated 3D LV quantification echocardiography and 3D-STE are reliable tools in LV volumetric and systolic function assessment about CMRIas a standard method. 3D speckle echocardiography is comparable to CMRI in global wall hypokinesia detection but less sensitive in segmental wall hypokinesia which mandates further studies.

Quantitative analysis of mitral valve morphology in atrial functional mitral regurgitation using real-time 3-dimensional echocardiography atrial functional mitral regurgitation

Background

Atrial fibrillation (AF) can result in atrial functional mitral regurgitation (MR), but the mechanism remains controversial. Few data about the relationship between the 3-dimensional morphology of the MV and the degree of MR in AF exist.

Methods

Real-time 3-dimensional transesophageal echocardiography (3D-TEE) of the MV was acquired in 168 patients with AF (57.7% persistent AF), including 25 (14.9%) patients with moderate to severe MR (the MR+ group) and 25 patients without AF as controls. The 3-dimensional geometry of the MV apparatus was acquired using dedicated quantification software.

Results

Compared with the group of patients with no or mild MR (the MR- group) and the controls, the MR+ group had a larger left atrium (LA), a more dilated mitral annulus (MA), a reduced annular height to commissural width ratio (AHCWR), indicating flattening of the annular saddle shape, and greater leaflet surfaces and tethering. MR severity was correlated with the MA area (r² = 0.43, P < 0.01) and the annulus circumference (r² = 0.38, P < 0.01). A logistic regression analysis indicated that the MA area (OR: 1.02, 95% CI: 1.01–1.03, P < 0.01), AHCWR (OR: 0.24, 95% CI: 0.14–0.35, P = 0.04) and MV tenting volume (OR: 3.24, 95% CI: 1.16–9.08, P = 0.03) were independent predictors of MR severity in AF patients.

Conclusions

The mechanisms of “atrial functional MR” are complex and include dilation of the MA, flattening of the annular saddle shape and greater leaflet tethering.

Which Cardiac Structure Lies Nearby? Revisiting Two-Dimensional Cross-Sectional Anatomy

Two-dimensional (2D) transthoracic echocardiography is one of the most used diagnostic tools in clinical cardiology. Similarly, 2D transesophageal echocardiography is considered an indispensable tool for cardiologists and cardiac anesthesiologists worldwide. However, because of their tomographic nature, both techniques display only thin cut planes of a given area of the heart, which are far from representing the "anatomic reality." It is widely accepted that experienced echocardiographers are able to reconstruct mentally a three-dimensional image of any cardiac structure on the basis of their interpretation of multiple tomographic slices. However, this may not be the case with less experienced echocardiographers. In particular, the authors noticed that less experienced echocardiographers are almost totally unaware of which structures lie "nearby" a given 2D tomographic plane, that is, what is adjacent in the elevation plane. In this article, the authors report the use of three-dimensional transesophageal echocardiographic images to discover which structures are located nearby (i.e., "behind" and "in front") the corresponding 2D cross-sections. The authors believe that this novel use of three-dimensional echocardiography is a unique aid to disclose what cannot be seen in a given 2D cross-section, thereby expanding our understanding of 2D echocardiographic anatomy. This may be an effective method to encourage all to "think" in three dimensions, even when they use 2D echocardiography.

Relation of mitral valve morphology to surgical repair results in patients with mitral valve prolapse: A three-dimensional transesophageal echocardiography study

BACKGROUND

The identification of predictors of mitral valve (MV) repair results is important for quality improvement in cardiac surgery. The aim of this study was to evaluate the relationship between MV morphological quantification by three-dimensional (3D) transesophageal echocardiography and mitral repair results.

METHODS

Fifty-four patients with MV prolapse who were submitted to surgical repair were divided into 2 groups according to their postoperative mitral regurgitation (MR) degree (group 1, grade 0-I MR; group 2, ≥grade II MR). Morphological parameters related to the mitral ring, dimension of leaflets and prolapse, coaptation line, distance from papillary muscles to the leaflet border and valve angles were analyzed by 3D MV quantification. Cardiac remodeling and MR quantitative parameters were also evaluated.

RESULTS

There was no correlation between 3D MV quantification and surgical results; a multivariate analysis did not show an association between morphological parameters and surgical outcome. The distance from the posteromedial papillary muscle to the leaflet border was higher (P = .038) in patients with ≥grade II postoperative MR. The left atrial diameter, left ventricular end-systolic diameter, left ventricular end-diastolic and end-systolic volumes were larger in patients with a significant residual MR (P < .05).

CONCLUSION

Three-dimensional MV quantification did not predict the postoperative MR grade; however, the distance from the posteromedial papillary muscles to the leaflet border may be related to suboptimal repair results. Furthermore, excessive cardiac remodeling was related to postoperative MR ≥ grade II, what could suggest a potential benefit of early surgical treatment.

Assessment of the mitral valve coaptation zone with 2D and 3D transesophageal echocardiography before and after mitral valve repair

Background

Mitral valve (MV) coaptation is very important in MV repair patients. But accurate quantitation of the degree of MV coaptation remains challenging. This study aimed to evaluate the utility of two-dimensional (2D) and three-dimensional (3D) transesophageal echocardiography (TEE) to assess MV coaptation before and after MV repair.

Methods

Forty-eight patients [(age: 52.23±13.31 years; 26 men (54.17%)] undergoing MV repair for mitral regurgitation (MR) were studied. We assessed the utility of 2D and 3D TEE to assess MV coaptation before and after MV repair. Complete conventional 2D and 3D TEE studies were performed, and the degree of the MV coaptation defect before and after surgery was assessed by measuring the MV coaptation length (CL) and length index (CLI) with 2D TEE, and the coaptation area (CA) and coaptation area index (CAI) with 3D TEE.

Results

CL and CLI were measured successfully in 46 (95.83%) patients and CA and CAI in 39 (81.25%). Compared with preoperatively, postoperative CL, CLI, CA, and CAI were significantly increased (CL: 4.99±0.79 to 9.66±1.09 mm, P<0.05; CLI: 9.30%±2.66% to 38.24%±3.82%, P<0.05; CA: 158.49±64.17 to 371.33±143.57 mm², P<0.05; CAI: 9.71%±2.76% to 36.24%±7.26%, P<0.05). Spearman's rank correlation analysis revealed that the CLI and CAI had a significant negative correlation with the degree of MR (r=-0.97, P<0.01; r=-0.92, P<0.01, respectively). Furthermore, Pearson's correlation analysis revealed that the CLI was significantly correlated with the CAI both preoperatively (r=-0.66, P<0.01) and postoperatively (r=-0.67, P<0.01).

Conclusions

The coaptation variables increased significantly in patients undergoing MV repair. The CLI and CAI significantly correlated with MR severity. The CL and CLI determined with 2D TEE are more feasible than the CA and CAI determined with 3D TEE. Both 2D and 3D variables may complement each other for aiding MV repair. 2D CLI is an alternative to 3D CAI due to its simplicity.

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.

Three-dimensional Echocardiography in Congenital Heart Disease: An Expert Consensus Document from the European Association of Cardiovascular Imaging and the American Society of Echocardiography

Three-dimensional echocardiography (3DE) has become important in the management of patients with congenital heart disease (CHD), particularly with pre-surgical planning, guidance of catheter intervention, and functional assessment of the heart. 3DE is increasingly used in children because of good acoustic windows and the non-invasive nature of the technique. The aim of this paper is to provide a review of the optimal application of 3DE in CHD including technical considerations, image orientation, application to different lesions, procedural guidance, and functional assessment.

Ultrasound in cardiac trauma

In the perioperative period, the emergency department or the intensive care unit accurate assessment of variable chest pain requires meticulous knowledge, diagnostic skills, and suitable usage of various diagnostic modalities. In addition, in polytrauma patients, cardiac injury including aortic dissection, pulmonary embolism, acute myocardial infarction, and pericardial effusion should be immediately revealed and treated. In these patients, arrhythmias, mainly tachycardia, cardiac murmurs, or hypotension must alert physicians to suspect cardiovascular trauma, which would potentially be life threatening. Ultrasound of the heart using transthoracic and transesophageal echocardiography are valuable diagnostic tools that can be used interchangeably in conjunction with other modalities such as the electrocardiogram and computed tomography for the diagnosis of cardiovascular abnormalities in trauma patients. Although ultrasound of the heart is often underused in the setting of trauma, it does have the advantages of being easily accessible, noninvasive, and rapid bedside assessment tool. This review article aims to analyze the potential cardiac injuries in trauma patients, and to provide an elaborate description of the role of echocardiography for their accurate diagnosis.

Direct Digital Demultiplexing of Analog TDM Signals for Cable Reduction in Ultrasound Imaging Catheters

In real-time catheter-based 3-D ultrasound imaging applications, gathering data from the transducer arrays is difficult, as there is a restriction on cable count due to the diameter of the catheter. Although area and power hungry multiplexing circuits integrated at the catheter tip are used in some applications, these are unsuitable for use in small sized catheters for applications, such as intracardiac imaging. Furthermore, the length requirement for catheters and limited power available to on-chip cable drivers leads to limited signal strength at the receiver end. In this paper, an alternative approach using analog time-division multiplexing (TDM) is presented, which addresses the cable restrictions of ultrasound catheters. A novel digital demultiplexing technique is also described, which allows for a reduction in the number of analog signal processing stages required. The TDM and digital demultiplexing schemes are demonstrated for an intracardiac imaging system that would operate in the 4- to 11-MHz range. A TDM integrated circuit (IC) with an 8:1 multiplexer is interfaced with a fast analog-to-digital converter (ADC) through a microcoaxial catheter cable bundle, and processed with a field-programmable gate array register-transfer level simulation. Input signals to the TDM IC are recovered with -40-dB crosstalk between the channels on the same microcoax, showing the feasibility of this system for ultrasound imaging applications.

Automated Assessment of Right Ventricular Volumes and Function Using Three-Dimensional Transesophageal Echocardiography

Assessment of right ventricular (RV) function is known to be of diagnostic value in patients with RV dysfunction. Because of its complex anatomic shape, automated determination of the RV volume is difficult and strong reliance on geometric assumptions is not desired. A method for automated RV assessment was developed using three-dimensional (3-D) echocardiography without relying on a priori knowledge of the cardiac anatomy. A 3-D adaptive filtering technique that optimizes the discrimination between blood and myocardium was applied to facilitate endocardial border detection. Filtered image data were incorporated in a segmentation model to automatically detect the endocardial RV border. End-systolic and end-diastolic RV volumes, as well as ejection fraction, were computed from the automatically segmented endocardial surfaces and compared against reference volumes manually delineated by two expert cardiologists. The results reported good performance in terms of correlation and agreement with the results from the reference volumes.

Incidental echocardiographic findings of a quadricuspid aortic valve associated with aortic regurgitation in a cat

Case summary

A 10-month-old male domestic shorthair cat was brought to Kitanomori Animal Hospital for routine castration. Preoperative thoracic radiography revealed a mildly enlarged heart silhouette, and transthoracic echocardiography (ECHO) suggested a quadricuspid aortic valve associated with central aortic regurgitation (regurgitant fraction 31%). After sedation with intramuscular medetomidine and midazolam for castration, heart rate decreased from 193 to 76 beats per minute. ECHO under sedation revealed two equally small and two equally large aortic valve cusps, suggesting a type C quadricuspid aortic valve. The findings were confirmed by real-time three-dimensional ECHO.

Relevance and novel information

This case reveals the echocardiographic features of a feline quadricuspid aortic valve and shows that transthoracic ECHO is useful to examine aortic valve morphology in cats. It also suggests that echocardiographic screening may be beneficial for detecting congenital cardiac anomalies in apparently healthy cats.

[Application fields of intraoperative transesophageal 3D echocardiography]

Intraoperative transesophageal echocardiography (TEE) is an established diagnostic tool and has to be regarded as the standard of care for intraoperative monitoring and cardiac surgical decision-making. Furthermore, intraoperative TEE is also used for monitoring and assessment of hemodynamic changes and the detection of previously unknown pathologies. In the past few years 3D-TEE has extended the spectrum of 2D-TEE by allowing pathomorphological features to be more easily and intuitively linked to the anatomy of the heart and the great vessels. Thus, a comprehensive 2D-TEE examination is favorably complemented by focused 3D-TEE. Especially during mitral valve surgery, 3D-TEE has proven its superiority in the diagnosis of the underlying pathology as demonstrated by a large number of studies in this field. This review presents the available data about the role of intraoperative 3D-TEE echocardiography and introduces practical fields of application.

Structure and function of the tricuspid and bicuspid regurgitant aortic valve: an echocardiographic study

OBJECTIVES

The emerging new treatment options for aortic valve disease call for more sophisticated diagnostics. We aimed to describe the echocardiographic pathophysiology and characteristics of the purely regurgitant aortic valve in detail.

METHODS

Twenty-nine men, with chronic aortic regurgitation without concomitant heart disease referred for aortic valve intervention, underwent 2D transoesophageal echocardiographic (TEE) examination prior to surgery according to a previously published matrix. Measurements of the aortic valve apparatus in long and short axis view were made in systole and diastole and analysed off-line. The aortic valves were grouped as tricuspid (TAV) or bicuspid (BAV), and classified by regurgitation mechanism.

RESULTS

Twenty-four examinations were eligible for analysis of which 13 presented TAV and 11 BAV. The regurgitation mechanism was classified as dilatation of the aorta in 6 cases, as prolapse in 11 cases and as poor cusp tissue quality or quantity in 7 cases. The ventriculo-aortic junction (VAJ) and valve opening were closely related (TAV r = 0.5, BAV r = 0.73) but no correlation was found between the VAJ and the maximal sinus diameter (maxSiD) or the sinotubular junction (STJ). However, the STJ and maxSiD were significantly related (TAV vs BAV: systole r = 0.9, r = 0.8; diastole r = 0.9, r = 0.7), forming an entity. The conjoined BAV cusps were shorter than the anterior cusps when closed (P = 0.002); the inter-commissural distances of the cusps in the BAV group were significantly different (P = 0.001 resp. 0.03) in both systole and diastole.

CONCLUSIONS

The VAJ was independent of other aortic dimensions and should thereby be considered as a separate entity with influence on valve opening. The detailed 2D TEE measurements of this study add further important information to our knowledge about the function and echocardiographic anatomy of the pathological aortic valve and root either as a stand-alone examination or as a benchmark and complement to 3D echocardiography. This may have an impact on decisions regarding repairability of the native aortic valve.

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.

Role of modern 3D echocardiography in valvular heart disease

Three-dimensional (3D) echocardiography has been conceived as one of the most promising methods for the diagnosis of valvular heart disease, and recently has become an integral clinical tool thanks to the development of high quality real-time transesophageal echocardiography (TEE). In particular, for mitral valve diseases, this new approach has proven to be the most unique, powerful, and convincing method for understanding the complicated anatomy of the mitral valve and its dynamism. The method has been useful for surgical management, including robotic mitral valve repair. Moreover, this method has become indispensable for nonsurgical mitral procedures such as edge to edge mitral repair and transcatheter closure of paravaluvular leaks. In addition, color Doppler 3D echo has been valuable to identify the location of the regurgitant orifice and the severity of the mitral regurgitation. For aortic and tricuspid valve diseases, this method may not be quite as valuable as for the mitral valve. However, the necessity of 3D echo is recognized for certain situations even for these valves, such as for evaluating the aortic annulus for transcatheter aortic valve implantation. It is now clear that this method, especially with the continued development of real-time 3D TEE technology, will enhance the diagnosis and management of patients with these valvular heart diseases.

Real time three-dimensional transesophageal echocardiographic evaluation of aortic valve perforation

OBJECTIVES

This study evaluated the feasibility of real time three-dimensional transesophageal echocardiography (RT3DTEE) in the diagnosis and localization of aortic valve perforation.

METHODS

Aortic valve perforation was diagnosed in 12 patients by multiplane two-dimensional transesophageal echocardiography (2DTEE). We studied the feasibility of RT3DTEE using en face view in detection and precise localization of the aortic valve perforation. The artifactual dropout on RT3D images of aortic valve can mimic perforation and lead to a false positive diagnosis. We defined a true perforation as the hole with thicker margin and its visibility in both systole and diastole. We combined the RT3D images from 10 subjects with relatively normal aortic valve without perforation (test group) with the 12 with perforation for a blind review by an experienced echocardiographer.

RESULTS

There were 14 perforations in 12 patients. The perforation was located in the left coronary cusp in 1, the noncoronary cusp in 7, and the right coronary cusp in 6 patients. In the subgroup of 9 patients with 11 perforations, all were confirmed at surgery. In test group the artifact mimicking perforation was frequently encountered (7/10 or 70%). However, they did not meet the criteria for true perforation except in 1 (1 false positive). All true perforations were correctly recognized.

CONCLUSIONS

En face imaging with RT3DTEE can be used to confirm aortic valve perforation and its spatial location. However, RT3D should be used as an extension to comprehensive 2DTEE and color flow imaging.

Calcific extension towards the mitral valve causes non-rheumatic mitral stenosis in degenerative aortic stenosis: real-time 3D transoesophageal echocardiography study

Objective

Mitral annular/leaflet calcification (MALC) is frequently observed in patients with degenerative aortic stenosis (AS). However, the impact of MALC on mitral valve function has not been established. We aimed to investigate whether MALC reduces mitral annular area and restricts leaflet opening, resulting in non-rheumatic mitral stenosis.

Methods

Real-time three-dimensional transoesophageal images of the mitral valve were acquired in 101 patients with degenerative AS and 26 control participants. The outer and inner borders of the mitral annular area (MAA) and the maximal leaflet opening angle were measured at early diastole. The mitral valve area (MVA) was calculated as the left ventricular stroke volume divided by the velocity time integral of the transmitral flow velocity.

Results

Although the outer MAA was significantly larger in patients with AS compared to control participants (8.2±1.3 vs 7.3±0.9 cm², p<0.001), the inner MAA was significantly smaller (4.5±1.1 vs 5.9±0.9 cm², p<0.001), resulting in an average decrease of 45% in the effective MAA. The maximal anterior and posterior leaflet opening angle was also significantly smaller in patients with AS (64±10 vs 72±8°, p<0.001, 71±12 vs 87±7°, p<0.001). Thus, MVA was significantly smaller in patients with AS (2.5±1.0 vs 3.8±0.8 cm², p<0.001). Twenty-four (24%) patients with AS showed MVA <1.5 cm². Multivariate regression analysis including parameters for mitral valve geometry revealed that a decrease in effective MAA and a reduced posterior leaflet opening angle were independent predictors for MVA.

Conclusions

Calcific extension to the mitral valve in patients with AS reduced effective MAA and the leaflet opening, resulting in a significant non-rheumatic mitral stenosis in one-fourth of the patients.

Update on Perioperative Right Heart Assessment Using Transesophageal Echocardiography

Purpose of the review. This review aims to summarize recent findings relevant for perioperative 2- and 3-dimensional imaging of the right heart with transesophageal echocardiography. Special attention is given to developments that are likely to affect future approaches for prevention and therapy of perioperative right heart failure. Recent findings. Three-dimensional transesophageal echocardiography techniques are becoming more common for the evaluation of anatomy, volumes, and functional indices. Summary. Right heart failure continues to contribute to morbidity and mortality in the context of cardiothoracic surgery. The advent and widespread clinical use of innovative tools permitting more accurate echocardiographic assessment of the right heart will open the door to renewed interest in novel therapeutic strategies.

3-dimensional echocardiography and its role in preoperative mitral valve evaluation

Echocardiography plays a key role in the preoperative evaluation of mitral valve disease. 3-dimensional echocardiography is a relatively new development that is being used more and more frequently in the evaluation of these patients. This article reviews the available literature comparing the use of this new technology to classic techniques in the assessment of mitral valve pathology. The authors also review some of the novel insights learned from 3-dimensional echocardiography and how they may be used in surgical decision making and planning.