Utility of Combined Two-Dimensional and Three-Dimensional Transesophageal Imaging for Catheter-Based Mitral Valve Clip Repair of Mitral Regurgitation

Transoesophageal echocardiography beyond the echo-laboratory. An expert consensus paper of the working group of echocardiography of the hellenic society of cardiology

Transoesophageal echocardiography (TOE) is a well-established and valid imaging modality, providing more accurate and of higher quality information than transthoracic echocardiography (TTE) for several specific diagnoses and recently a useful guide of an increasing number of catheter-based and surgical interventions. The present paper represents an effort by the Echocardiography Working Group (WG) of the Hellenic Society of Cardiology to state the essential steps of the TOE exam performed beyond the echo lab: a) in the operating rooms intraoperatively during either transcatheter interventions, or cardiothoracic surgery and b) in the intensive care unit for critically ill patients' monitoring. This paper includes information and tips and tricks about the pre-procedural evaluation, the procedural echocardiographic guidance, and post-procedural evaluation of the result and potential complications.

Percutaneous closure of simple congenital heart diseases under echocardiographic guidance

Congenital heart disease (CHD), birth defect with the highest incidence rates worldwide, and is mainly characterized by the abnormal internal structure of the heart or/and the anatomical structure of great vessels. In the past few decades, CHD repair surgery through standard median sternotomy incision combined with cardiopulmonary bypass (CPB) technology has been considered the gold standard for surgical correction of heart and great vessels. With the promotion and clinical application of interventional catheterization technology, transcatheter closure of CHD under radioactive radiation has gradually been recognized and applied. However, its radiation exposure and potential complications related to arteriovenous vessels still face challenges. In recent years, an increasing number of surgeons have explored new surgical procedures, for the safe and effective treatment of CHD, as far as possible to reduce surgical trauma, avoid radiation exposure, and improve the cosmetic effect. Therefore, on the premise of satisfactory exposure or guidance, how to integrate ultrasound and percutaneous interventional technology remained the focus of the exploration. This mini-review highlights and summarizes the signs of progress of ultrasound intervention in the last decade that have proven the effectiveness and operability of a well-established procedure for percutaneous closure of congenital heart diseases under echocardiographic guidance only. We discuss potential diseases that will benefit from this emerging procedure based on this progress. Owing to the crucial advantages played by this strategy in the treatment of CHD, better understanding and promotion of this less exploited field may contribute to the development of therapeutics targeting CHD, improve medical utilization rate, promote the optimization of medical resources, and ultimately achieve precise and efficient medical treatment.

Multimodality imaging for patient selection, procedural guidance, and follow-up of transcatheter interventions for structural heart disease: a consensus document of the EACVI Task Force on Interventional Cardiovascular Imaging: part 1: access routes, transcatheter aortic valve implantation, and transcatheter mitral valve interventions

Transcatheter therapies for the treatment of structural heart diseases (SHD) have expanded dramatically over the last years, thanks to the developments and improvements of devices and imaging techniques, along with the increasing expertise of operators. Imaging, in particular echocardiography, is pivotal during patient selection, procedural monitoring, and follow-up. The imaging assessment of patients undergoing transcatheter interventions places demands on imagers that differ from those of the routine evaluation of patients with SHD, and there is a need for specific expertise for those working in the cath lab. In the context of the current rapid developments and growing use of SHD therapies, this document intends to update the previous consensus document and address new advancements in interventional imaging for access routes and treatment of patients with aortic stenosis and regurgitation, and mitral stenosis and regurgitation.

Clinical Utility of Three-Dimensional Echocardiography in the Evaluation of Mitral Valve Disease: Tips and Tricks

Although real-time 3D echocardiography (RT3DE) has only been introduced in the last decades, its use still needs to be improved since it is a time-consuming and operator-dependent technique and acquiring a good quality data can be difficult. Moreover, the additive value of this important diagnostic tool still needs to be wholly appreciated in clinical practice. This review aims at explaining how, why, and when performing RT3DE is useful in clinical practice.

3D echocardiography in mitral valve prolapse

Mitral valve prolapse (MVP) is the leading cause of mitral valve surgery. Echocardiography is the principal imaging modality used to diagnose MVP, assess the mitral valve morphology and mitral annulus dynamics, and quantify mitral regurgitation. Three-dimensional (3D) echocardiographic (3DE) imaging represents a consistent innovation in cardiovascular ultrasound in the last decades, and it has been implemented in routine clinical practice for the evaluation of mitral valve diseases. The focus of this review is the role and the advantages of 3DE in the comprehensive evaluation of MVP, intraoperative and intraprocedural monitoring.

Combined MitraClip and Left Atrial Appendage Occlusion: Is It Still a Utopia?

Atrial fibrillation (AF) is the most common cardiac arrhythmia, affecting 32 million individuals worldwide, particularly the elderly. It is the main cause of ischemic strokes. Oral anticoagulation (OAC) is the gold standard strategy for stroke prevention. Still, there is a not negligible share of patients who have contraindications to this therapy, more frequently due to an increased risk of bleeding. AF is often associated with moderate-severe mitral regurgitation (MR), the second most frequent valvular disease in elderly patients. Data from the literature reported that more than half of patients with severe mitral regurgitation are not suitable candidates for cardiac surgery. Given the progressive aging of the population and the simultaneous increase in the number of patients with comorbidities, the advent of new therapeutic strategies, such as the combined approach of Left Atrial Appendage Occlusion (LAAO) and MitraClip procedure, is acquiring great interest. At present, the category of patients who may benefit from combined percutaneous therapies and the long-term risks and benefits might not have been identified. Despite the efforts of researchers, the correct selection of patients is a very important clinical need that has not yet been met to avoid committing human and financial resources to interventions that may be unnecessary. It is conceivable that the most modern and recent innovations in cardiovascular imaging, particularly three-dimensional echocardiography and new methods of volume imaging, could improve our ability to select patients appropriately. Since data in the literature are scarce, future studies will be needed to evaluate the efficacy and safety of combined MitraClip and LAA occlusion.

Advances in Procedural Echocardiographic Imaging in Transcatheter Edge-to-Edge Repair for Mitral Regurgitation

Transcatheter edge-to-edge repair (TEER) therapy is recommended by the American College of Cardiology/American Heart Association (ACC/AHA) guidelines for selected patients with symptomatic severe or moderate-severe mitral regurgitation (MR). Echocardiography, in particular transesophageal echocardiography (TEE), plays a critical role in procedural planning and guidance for TEER. Recent innovations and advances in TEE techniques including three-dimensional (3D) imaging, unlimited x-plane imaging, live 3D multiplanar reconstruction, as well as transillumination imaging with color Doppler and transparency rendering have further enhanced procedural imaging for TEER, especially for complex diseases including commissural defects, clefts, and multi-segment pathologies. This review discusses the technology of these advanced procedural imaging techniques and provides a "step-by-step" guide on how to apply them during the TEER procedure with a focus on their added values in treatment of complex valve lesions.

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.

Transesophageal echocardiography simulation: A review of current technology

Transesophageal echocardiography (TEE) has experienced tremendous increase in interest and demand alongside the rapid growth of transcatheter structural cardiac interventions. TEE instruction prolongs the procedure, increasing the risk of probe malfunction from overheating and patient complications from prolonged sedation. Echocardiographic simulation programs have been developed to hone the procedural skills of novice operators in a time-unrestricted, low-pressure environment before they perform TEEs on real patients. Simulators likely benefit training in interventional TEE for the same reasons. We searched PubMed, basic Google, and Google Scholar for currently marketed TEE simulators, including foreign as well as US companies. We queried the vendors regarding features of the simulators that pertain to effective instructional design for diagnostic TEE. We also queried regarding the simulators' applicability to training in interventional TEE. The vendors' responses are reported here. In addition, we discuss the specific training needs for structural heart interventions, for which echocardiographic simulation could be a powerful educational tool. Lastly, we discuss the role of simulation for formative and summative assessment, and the advances required to improve training in complex procedures within the field of interventional echocardiography.

Adjunctive use of fluoroscopy during MitraClip implantation reduces procedural complexity: The parallax technique

BACKGROUND

During MitraClip implantation sub-valvular correction of trajectory and/or alignment may increase adverse clip or leaflet events. With systematic adjunctive use of fluoroscopy ("Parallax technique"), we aimed to assess parameters that minimize the need for corrective measures and help increase procedural efficiency.

METHODS

We retrospectively analyzed 30 patients without (Fl-) and 39 patients utilizing adjunctive fluoroscopy (Fl+) during MitraClip implantation. After establishing trajectory and supra-valvular alignment, the Parallax technique was utilized. Trajectory and alignment are maintained during advancement.

RESULTS

All patients had 3 or 4+ MR. There were no differences in baseline demographics. The average number of clips (Fl- vs Fl+) was 1.72 ± 0.8 vs 1.59 ± 0.5, p = .57. For the first clip, the need for sub-valvular alignment (80% vs. 36%, p = .0001), eversion with retraction back to left atrium (23% vs. 10%, p = .001) and the number of grasps (2.3 ± 1.2 vs 1.4 ± 0.9) was reduced. The time from transseptal puncture to first clip deployment (71 ± 21 vs 44 ± 16 min, p = .01) was reduced. Procedural success was achieved in all but one patient in the Fl- group (p = ns). There were no differences noted for in-hospital or 30-day outcomes.

CONCLUSIONS

Systematic use of a simple and easy to implement "Parallax technique" was associated with reduced need for sub-valvular manipulation and was associated with improved procedural times. Further larger scale studies are needed to assess the applicability of the technique.

Management of Valvular Disease During Pregnancy: Evolving Role of Percutaneous Treatment

Valvular heart disease (VHD) is encountered in approximately 1% of pregnancies, significantly increasing both maternal and foetal risk. Rheumatic VHD remains the most common form in non-Western countries, whereas congenital heart disease dominates in the Western world. The risk of complications varies according to the type and severity of the underlying VHD. Moreover, pregnancy is a hypercoagulable state associated with increased risk of thromboembolism. The authors review the main VHDs encountered during pregnancy, and suggest management strategies based on the 2018 European Society of Cardiology recommendations for the management of pregnant women with VHD, providing an overview of classical and new transcatheter structural therapeutic options with a special focus on radiation exposure and anticoagulation drug management.

Transesophageal echocardiography complications associated with interventional cardiology procedures

BACKGROUND

Although there have been several reports documenting complications related with transesophageal echocardiography (TEE) manipulation following cardiac surgery, there is a paucity of data regarding the safety of TEE used to guide catheter-based interventions. The aim of this study was to determine the prevalence, types and risk factors of complications associated with procedures requiring active TEE guidance.

METHODS

This study included 1249 consecutive patients undergoing either transcatheter aortic valve implantation (TAVI), Mitraclip, left atrial appendage occlusion (LAAO) or paravalvular leak closure (PVLC). Patients were divided into 2 cohorts based on the degree of probe manipulation required to guide the procedure and the risk of developing a TEE-related complication: low-risk (TAVI, n = 1037) and high-risk (Mitraclip, LAAO and PVLC, n = 212). Patients were further analyzed according to the occurrence of major and minor TEE-related complications.

RESULTS

The overall incidence of TEE-related complications was 0.9% in the TAVI group and 6.1% in the rest of the cohort (P < .001). Patients in the high-risk cohort had also a higher incidence of major-complications (2.8% vs 0.6%, P = .008), and factors associated with an increased risk were being underweight, having a prior history of gastrointestinal bleeding and the use of chronic steroids/immunosuppressive medications. Procedural time under TEE-manipulation was longer in patients exhibiting complications and was an independent predictor of major complications (OR = 1.13, 95% CI 1.01-1.25, for each 10 minutes increments in imaging time). Patients with major complications undergoing Mitraclip had the longest median time under TEE-manipulation (297 minutes) and a risk of developing a major-complication that was 10.64 times higher than the rest of the cohort (95% CI 3.30-34.29, P < .001).

CONCLUSION

The prevalence of TEE-related complications associated with interventional procedures is higher than previously reported. Undergoing a prolonged procedure, particularly in the setting of Mitraclip, was the main factor linked to TEE-related complications.

Utilization of intra-aortic balloon pump to allow MitraClip procedure in patients with non-coapting mitral valve leaflets: a case series

Background

The MitraClip (MC) procedure was designed for high-risk surgical patients with severe mitral regurgitation (MR). Some patients do not meet the required anatomical criteria due to advanced left ventricular remodelling and mitral annular dilatation leading to leaflet tethering and insufficient coaptation surface. Theoretically, ‘temporary remodelling’ of the mitral valve apparatus by pharmacological and/or mechanical support using intra-aortic balloon pump (IABP) could improve leaflets coaptation.

Case summary

We report a case series of four patients with severe MR and non-coapting leaflets who underwent MC implantation. Sufficient coaptation was achieved only after insertion of IABP. The first patient presented with worsening heart failure and severe MR after a non-reperfused posterior wall myocardial infarction (MI), underwent a successful procedure with good results. The second patient presented with worsening heart failure secondary to rheumatic MR, and underwent MC procedure with good results after the insertion of IABP. The third patient developed worsening heart failure and severe MR 2 months after an acute inferior-lateral MI, and underwent a successful procedure. The fourth patient presented with respiratory failure, the patient underwent the procedure, but unfortunately died a few days following the procedure from multiorgan failure. In each case, the insertion of the IABP decreased annular mitral diameter and increased the coaptation surface as assessed by transoesophageal echocardiography.

Discussion

For patients suffering from symptomatic severe MR who are not suitable candidates for MC procedure, IABP system enabled us to overcome mitral leaflet gap and complete the MC procedure successfully.

Percutaneous Transcatheter Edge-to-Edge MitraClip Technique: A Practical "Step-by-Step" 3-Dimensional Transesophageal Echocardiography Guide

Recent innovations and advancements in 3-dimensional (3D) echocardiography allow for better understanding of anatomic relationships and improve communication with the interventional cardiologist for guidance of catheter-based interventions. The mitral valve lends itself best for imaging with transesophageal echocardiography (TEE). Consequently, the role of 3D TEE in guiding catheter-based mitral interventions has been evolving rapidly. Although several publications have reported on the advantages and role of 3D TEE in guiding one or more of the steps involved in percutaneous mitral valve repair using the MitraClip, none offer a comprehensive and practical user-friendly guide. This review article provides the reader with practical intraprocedural tips on use of 3D TEE to guide all relevant steps involved in the procedure including how to acquire the images needed and what to look for.

Differences in Two- and Three-Dimensional Assessment of the Mitral Valve by Novices and Experts, Illustrated Using Anterior Mitral Valve Leaflet Length

OBJECTIVES

In this measurement validation study, the authors evaluated agreement between 2-dimensional (2D) and three-dimensional (3D) transesophageal echocardiography (TEE), measuring anterior mitral valve leaflet length by both novice and experienced echocardiographers.

DESIGN

This was a retrospective, observational study.

SETTING

Single university hospital.

PARTICIPANTS

Analyses on datasets from 44 patients.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Fifty datasets from 44 patients with mitral regurgitation were analyzed by 4 observers (2 novices, 2 experts). All observers measured the anterior mitral valve leaflet length from end-systolic 2D TEE images from the midesophageal longitudinal axis view and 3D software-augmented TEE images. The overall mean anterior mitral valve leaflet length was significantly shorter with 3D versus 2D TEE measurements (24.6 ± 4.5 mm v 26.2 ± 5.3 mm; p < 0.001), with novices measuring shorter leaflets than experts for both techniques (p < 0.001 and p = 0.005, respectively). Bland-Altman plots of 3D and 2D TEE measurements showed mean biases (95% limits of agreement) of -1.6 mm (-9.0 to 5.9 mm), -1.8 mm (-9.6 to 6.0 mm), and -1.3 mm (-8.4 to 5.7 mm) for all observers, novices, and experts, respectively. For 2D measurements, interobserver reliability was very strong among experts and strong among novices (Pearson's r = 0.83 v 0.66; p = 0.055). For 3D measurements, interobserver reliability was strong in experts and moderate in novices (Pearson's r = 0.69 v 0.51; p = 0.168).

CONCLUSION

For both novices and experts, 3D TEE measurements of the anterior mitral valve leaflet were significantly shorter than 2D measurements. Interobserver reliability was lowest for novices making 3D TEE measurements, indicating that reliable, quantitative evaluation of 3D TEE may require a greater amount of practice.

Echocardiography guidance of atrial septal defect closure

Transcatheter procedures offer less invasive approaches allowing rapid recovery and earlier hospital discharge. A number of international guidelines have defined the role of echocardiography spanning diagnosis, detailed anatomical assessment, device sizing and selection, peri-procedure guidance and post device surveillance. This review discusses the role of echocardiography in transcatheter atrial septal defect (ASD) closure. It describes a systematic approach to assessment including the crucial role of three dimensional echo and provides the reader with key information required during device sizing and procedure guidance.

Transcatheter Mitral Valve Repair Using the Edge-to-Edge Clip

Percutaneous intervention for mitral valve (MV) disease has been established as an alternative to open surgical MV repair in patients with prohibitive surgical risk. Multiple percutaneous approaches have been described and are in various stages of development. Edge-to-edge leaflet plication with the MitraClip (Abbott, Menlo Park, CA) is currently the only Food and Drug Administration-approved device specifically for primary or degenerative lesions. Use of the edge-to-edge clip for secondary mitral regurgitation is currently under investigation and may result in expanded indications. Echocardiography has significantly increased our understanding of the anatomy of the MV and provided us with the ability to classify and quantify the associated mitral regurgitation. For percutaneous interventions of the MV, transesophageal echocardiography imaging is used for patient screening, intraprocedural guidance, and confirmation of the result. Optimal outcomes require the echocardiographer and the proceduralist to have a thorough understanding of intra-atrial septal and MV anatomy, as well as an appreciation for the key points and potential pitfalls of each of the procedural steps. With increasing experience, more complex valvular pathology can be successfully percutaneously treated. In addition to two-dimensional echocardiography, advances in three-dimensional echocardiography and fusion imaging will continue to support the refinement of current technologies, the expansion of clinical applications, and the development of novel devices.

Interventional Echocardiography: Field of Advanced Imaging to Support Structural Heart Interventions

Multimodality imaging, particularly echocardiography, is paramount in planning and guiding structural heart disease interventions. Transesophageal echocardiography remains unique in its ability to provide real-time 2D and 3D imaging of valvular heart disease and anatomic cardiac defects, which directly impacts the strategy and outcome of these procedures. This review summarizes the role of transesophageal echocardiography in patients undergoing the most common structural heart disease interventions.

Multi-Modality Imaging in the Evaluation and Treatment of Mitral Regurgitation

OPINION STATEMENT

Mitral regurgitation (MR) is frequent and associated with increased mortality and morbidity when severe. It may be caused by intrinsic valvular disease (primary MR) or ventricular deformation (secondary MR). Imaging has a critical role to document the severity, mechanism, and impact of MR on heart function as selected patients with MR may benefit from surgery whereas other will not. In patients planned for a surgical intervention, imaging is also important to select candidates for mitral valve (MV) repair over replacement and to predict surgical success. Although standard transthoracic echocardiography is the first-line modality to evaluate MR, newer imaging modalities like three-dimensional (3D) transesophageal echocardiography, stress echocardiography, cardiac magnetic resonance (CMR), and computed tomography (CT) are emerging and complementary tools for MR assessment. While some of these modalities can provide insight into MR severity, others will help to determine its mechanism. Understanding the advantages and limitations of each imaging modality is important to appreciate their respective role for MR assessment and help to resolve eventual discrepancies between different diagnostic methods. With the increasing use of transcatheter mitral procedures (repair or replacement) for high-surgical-risk patients, multimodality imaging has now become even more important to determine eligibility, preinterventional planning, and periprocedural guidance.

MitraClip step by step; how to simplify the procedure

The MitraClip system is a device for percutaneous edge-to-edge reconstruction of the mitral valve in patients with severe mitral regurgitation who are deemed at high risk for surgery. Studies have underlined the therapeutic benefit of the MitraClip system for patients at extreme and high risk for mitral valve surgery, suffering from either degenerative or functional mitral regurgitation. The MitraClip procedure shows low peri-procedural complication rates, and a significant reduction in mitral regurgitation, as well as an improvement in functional capacity and most importantly quality of life. It hereby widens the spectrum of mitral valve repair for the Heart Team. The current review underscores the efficacy of the procedure and describes the technique to simplify the procedure.

Echocardiographic Imaging of the Mitral Valve for Transcatheter Edge-to-Edge Repair

Echocardiography continues to be the most effective imaging tool for the diagnosis and follow-up of mitral valve disease. This review addresses the use of transthoracic echocardiography and transesophageal echocardiography in the planning and guidance of transcatheter mitral valve therapies. Many of the echo-imaging guidance techniques are applicable to transcatheter intervention as a whole. However, given that the MitraClip is the only device approved for mitral regurgitation at present, specific attention is paid to this procedure, with additional focus on the guidance of noncentral repair. The imaging techniques discussed will be applicable to future devices.

Role of echocardiography for catheter-based management of valvular heart disease

Catheter-based treatment of valvular heart disease, such as transvalvular aortic valve replacement (TAVR) or mitral clip procedure, has been increasingly accepted as a treatment choice for the past several years. Such new treatment options have been changing the management of patients with valvular heart disease drastically while socio-economic factors regarding their application need to be taken into consideration. The use of echocardiography, including transesophageal echocardiography (TEE), for such catheter-based treatments is essential for the success of the procedures. Severe hypotension after TAVR is a life-threatening emergency. Rapid assessment and diagnosis in the catheterization or hybrid laboratory is essential for safety and a positive outcome. Possible diagnoses in this critical situation would include severe left ventricular dysfunction due to coronary obstruction, cardiac tamponade, aortic rupture, acute severe aortic and/or mitral valve regurgitation, and hypovolemia due to bleeding. Although new types of TAVR valves reduce para-valvular aortic regurgitation (AR) significantly, it is still important to judge the severity of para-valvular AR correctly in the laboratory. As for mitral clip procedure, TEE is vital for guiding and monitoring the entire process. Accurate identification of the location and the geometry of the regurgitant orifice is necessary for proper placement of the clip. Real-time 3D TEE provides helpful en face view of the mitral valve and clip together to this end. Residual mitral regurgitation (MR) after the first clip is not uncommon. Quick and precise imaging of the residual MR (location and severity) with TEE is extremely important for the interventionist to place the second clip and possibly third clip properly. After the completion of the clip procedure, mitral valve stenosis and also iatrogenic atrial septal defect need to be checked by TEE. Echocardiography, especially TEE, is also vital for the success of other newer trans-catheter procedures such as device closure of para-valvular MR of the artificial valve, valve in valve procedure, and native valve replacement.

Transcathether Valve Replacement and Valve Repair

Transcatheter aortic valve replacement for treatment of aortic stenosis has now become an accepted alternative to surgical valve replacement for some patients. In addition, transcatheter mitral valve repair is also routinely used in high surgical risk patients with mitral regurgitation. Other transcatheter procedures are in rapid development. The current review attempts to summarize the procedures and echocardiographic imaging used for transcatheter valve replacement or valve repair.

The use of imaging in new transcatheter interventions: an EACVI review paper

Transcatheter therapies for the treatment of valve heart diseases have expanded dramatically over the last years. The new developments and improvements in devices and techniques, along with the increasing expertise of operators, have turned the catheter-based approaches for valvular disease into an established treatment option. Various imaging techniques are used during these procedures, but echocardiography plays an essential role during patient selection, intra-procedural monitoring, and post-procedure follow-up. The echocardiographic assessment of patients undergoing transcatheter interventions places demands on echocardiographers that differ from those of the routine evaluation of patients with valve disease, and there is a need for specific expertise for those working in the cath lab. In the context of the current rapid developments and growing use of transcatheter valve therapies, this document intends to update the previous recommendations and address new advancements in imaging, particularly for those involved in any stage of the treatment of patients with valvular heart diseases.

Recent advances in echocardiography for valvular heart disease

Echocardiography is the imaging modality of choice for the assessment of patients with valvular heart disease. Echocardiographic advancements may have particular impact on the assessment and management of patients with valvular heart disease. This review will summarize the current literature on advancements, such as three-dimensional echocardiography, strain imaging, intracardiac echocardiography, and fusion imaging, in this patient population.

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.

Procedural guidance using advance imaging techniques for percutaneous edge-to-edge mitral valve repair

The complexity of structural heart disease interventions such as edge-to edge mitral valve repair requires integration of multiple highly technical imaging modalities. Real time imaging with 3-dimensional (3D) echocardiography is a relatively new technique that first, allows clear volumetric imaging of target structures such as the mitral valve for both pre-procedural diagnosis and planning in patients with degenerative or functional mitral valve regurgitation. Secondly it provides intra-procedural, real-time panoramic volumetric 3D view of structural heart disease targets that facilitates eye-hand coordination while manipulating devices within the heart. X-ray fluoroscopy and RT 3D TEE images are used in combination to display specific targets and movement of catheter based technologies in 3D space. This integration requires at least two different image display monitors and mentally fusing the individual datasets by the operator. Combined display technology such as this, allow rotation and orientation of both dataset perspectives necessary to define targets and guidance of structural disease device procedures. The inherently easy concept of direct visual feedback and eye-hand coordination allows safe and efficient completion of MitraClip procedures. This technology is now merged into a single structural heart disease guidance mode called EchoNavigator(TM) (Philips Medical Imaging Andover, MA). These advanced imaging techniques have revolutionized the field of structural heart disease interventions and this experience is exemplified by a cooperative imaging approach used for guidance of edge-to-edge mitral valve repair procedures.

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.

Asymmetric versus symmetric tethering patterns in ischemic mitral regurgitation: geometric differences from three-dimensional transesophageal echocardiography

BACKGROUND

Ischemic mitral regurgitation (IMR) results from mitral leaflet tethering from left ventricular remodeling. Heterogeneity in local or global left ventricular remodeling can result in differential tethering patterns and affect mitral valve function and the degree of mitral regurgitation. The aims of this study were to compare mitral valve geometry in asymmetric and symmetric tethering patterns using three-dimensional transesophageal echocardiography and to examine the impact of tethering pattern on IMR severity.

METHODS

Sixty-two patients with moderate or greater IMR underwent three-dimensional transesophageal echocardiography for the assessment of mitral valve geometry. Symmetric and asymmetric tethering patterns were determined by mitral regurgitation jet direction and coaptation of the mitral leaflets. The ratio of posterior to anterior leaflet tethering angle was a measure of tethering pattern (the higher the ratio, the more asymmetric the pattern). Overall tethering degree was assessed by tenting volume (TV).

RESULTS

Compared with the symmetric group, the asymmetric group had less annular dilatation, greater annular heights (10.3 ± 1.9 vs 8.5 ± 1.9 mm, P < .01), greater ratios of posterior to anterior leaflet tethering angle (3.19 ± 0.88 vs 1.95 ± 0.46, P < .01), and smaller TVs with more posterior displacement of the coaptation line. Vena contracta normalized to TV was greater in the asymmetric group (0.38 ± 0.24 vs 0.19 ± 0.13 cm/mL, P < .01). Multivariate analysis showed that both ratio of posterior to anterior leaflet tethering angle (β = 0.46, P < .001) and TV (β = 0.41, P = .001) were predictors of IMR severity.

CONCLUSIONS

Differences in mitral valve geometry are observed between asymmetric and symmetric tethering patterns in IMR. IMR degree is affected by both the pattern of tethering and the total degree of tethering. For the same degree of tethering, an asymmetric pattern is associated with increased MR severity. The pattern of mitral leaflet tethering may be considered in therapeutic decision making.

Three-Dimensional Echocardiography: Advancements in Qualitative and Quantitative Analyses of Mitral Valve Morphology in Mitral Valve Prolapse

Degenerative mitral valve disease (MVD) is the leading cause of organic mitral regurgitation (MR), one of the most common valvular heart disease in western countries. Substantial progresses in the surgical treatment of degenerative MVD have improved life expectancy of patients with significant MR. However, prognosis, surgical decision and timing of surgery strongly depend on the accurate characterization of mitral valve (MV) anatomy and pathology and on the precise quantification of MR. Three-dimensional (3D) echocardiography, a major technological breakthrough in the field of cardiovascular imaging, provides several advantages over two-dimensional (2D) imaging in the qualitative and quantitative evaluations of MV apparatus. In this review, we focus on the contribution of this new modality to the diagnosis of degenerative MVD, the quantitative assessment of MR severity, the selection and monitoring of surgical and percutaneous procedures, the evaluation of procedural outcomes. The results of a systematic and exhaustive search of the existing literature, restricted to real-time 3D echocardiography in adults, are here reported.

Echocardiographic guidance for diagnostic and therapeutic percutaneous procedures

Echocardiographic guidance has an important role in percutaneous cardiovascular procedures and vascular access. The advantages include real time imaging, portability, and availability, which make it an effective imaging modality. This article will review the role of echocardiographic guidance for diagnostic and therapeutic percutaneous procedures, specifically, transvenous and transarterial access, pericardiocentesis, endomyocardial biopsy, transcatheter pulmonary valve replacement, pulmonary valve repair, transcatheter aortic valve implantation, and percutaneous mitral valve repair. We will address the ways in which echocardiographic guidance provides these procedures with detailed information on anatomy, adjacent structures, and intraprocedural instrument position, thus resulting in improvement in procedural efficacy, safety and patient outcomes.

[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.

The evolving role of cardiac imaging in percutaneous valvular intervention

Surgical therapies have represented the primary evidence-based intervention to alter the natural history of valvular heart disease (VHD), however, the increasing incidence of patients at high surgical risk due to age and related co-morbid conditions has given rise to the need for alternative strategies. Thus, percutaneous approaches to VHD therapy have emerged as an important therapeutic option. Cardiovascular imaging plays a critical role in patient screening for percutaneous valvular interventions, during the procedure itself, and as part of follow-up for the identification of implant success/failure and complications. The technical demands on imaging in this context are highly specific. Although imaging has a significant role in the broader evaluation of valvular heart disease mechanism and severity, the purpose of this paper is to summarise the particular goals of cardiovascular imaging in the work-up for, during, and in the follow-up of percutaneous valvular intervention.

The role of echocardiography during mitral valve percutaneous interventions

Transesophageal echocardiography is routinely used to guide percutaneous interventions involving the mitral valve. Mitral balloon valvuloplasty for rheumatic mitral valve stenosis (MS) was the first percutaneous intervention to gain wide acceptance. New techniques have been developed to treat degenerative and functional mitral regurgitation (MR) as well as paravalvular mitral leak (PVML). This review describes the use of echocardiography for transcatheter treatment of MS, MR, and PVML.

Quantification of mitral valve anatomy by three-dimensional transesophageal echocardiography in mitral valve prolapse predicts surgical anatomy and the complexity of mitral valve repair

BACKGROUND

Three-dimensional (3D) transesophageal echocardiography (TEE) is more accurate than two-dimensional (2D) TEE in the qualitative assessment of mitral valve (MV) prolapse (MVP). However, the accuracy of 3D TEE in quantifying MV anatomy is less well studied, and its clinical relevance for MV repair is unknown.

METHODS

The number of prolapsed segments, leaflet heights, and annular dimensions were assessed using 2D and 3D TEE and compared with surgical measurements in 50 patients (mean age, 61 ± 11 years) who underwent MV repair for mainly advanced MVP.

RESULTS

Three-dimensional TEE was more accurate (92%-100%) than 2D TEE (80%-96%) in identifying prolapsed segments. Three-dimensional TEE and intraoperative measurements of leaflet height did not differ significantly, while 2D TEE significantly overestimated the height of the posterior segment P1 and the anterior segment A2. Three-dimensional TEE quantitative MV measurements were related to surgical technique: patients with more complex MVP (one vs two to four vs five or more prolapsed segments) showed progressive enlargement of annular anteroposterior (31 ± 5 vs 34 ± 4 vs 37 ± 6 mm, respectively, P = .02) and commissural diameters (40 ± 6 vs 44 ± 5 vs 50 ± 10 mm, respectively, P = .04) and needed increasingly complex MV repair with larger annuloplasty bands (60 ± 13 vs 67 ± 9 vs 72 ± 10 mm, P = .02) and more neochordae (7 ± 3 vs 12 ± 5 vs 26 ± 6, P < .01).

CONCLUSIONS

Measurements of MV anatomy on 3D TEE are accurate compared with surgical measurements. Quantitative MV characteristics, as assessed by 3D TEE, determined the complexity of MV repair.