Initial clinical experience using the EchoNavigator®-system during structural heart disease interventions

Digital health in cardiovascular medicine: An overview of key applications and clinical impact by the Portuguese Society of Cardiology Study Group on Digital Health

Digital health interventions including telehealth, mobile health, artificial intelligence, big data, robotics, extended reality, computational and high-fidelity bench simulations are an integral part of the path toward precision medicine. Current applications encompass risk factor modification, chronic disease management, clinical decision support, diagnostics interpretation, preprocedural planning, evidence generation, education, and training. Despite the acknowledged potential, their development and implementation have faced several challenges and constraints, meaning few digital health tools have reached daily clinical practice. As a result, the Portuguese Society of Cardiology Study Group on Digital Health set out to outline the main digital health applications, address some of the roadblocks hampering large-scale deployment, and discuss future directions in support of cardiovascular health at large.

Artificial Intelligence, Computational Simulations, and Extended Reality in Cardiovascular Interventions

Artificial intelligence, computational simulations, and extended reality, among other 21st century computational technologies, are changing the health care system. To collectively highlight the most recent advances and benefits of artificial intelligence, computational simulations, and extended reality in cardiovascular therapies, we coined the abbreviation AISER. The review particularly focuses on the following applications of AISER: 1) preprocedural planning and clinical decision making; 2) virtual clinical trials, and cardiovascular device research, development, and regulatory approval; and 3) education and training of interventional health care professionals and medical technology innovators. We also discuss the obstacles and constraints associated with the application of AISER technologies, as well as the proposed solutions. Interventional health care professionals, computer scientists, biomedical engineers, experts in bioinformatics and visualization, the device industry, ethics committees, and regulatory agencies are expected to streamline the use of AISER technologies in cardiovascular interventions and medicine in general.

Advances in TEE-Centric Intraprocedural Multimodal Image Guidance for Congenital and Structural Heart Disease

Percutaneous interventions are gaining rapid acceptance in cardiology and revolutionizing the treatment of structural heart disease (SHD). As new percutaneous procedures of SHD are being developed, their associated complexity and anatomical variability demand a high-resolution special understanding for intraprocedural image guidance. During the last decade, three-dimensional (3D) transesophageal echocardiography (TEE) has become one of the most accessed imaging methods for structural interventions. Although 3D-TEE can assess cardiac structures and functions in real-time, its limitations (e.g., limited field of view, image quality at a large depth, etc.) must be addressed for its universal adaptation, as well as to improve the quality of its imaging and interventions. This review aims to present the role of TEE in the intraprocedural guidance of percutaneous structural interventions. We also focus on the current and future developments required in a multimodal image integration process when using TEE to enhance the management of congenital and SHD treatments.

Pre-cath Laboratory Planning for Left Atrial Appendage Occlusion - Optional or Essential?

In the wake of rapid advancement in cardiovascular procedural technologies, physician-led preprocedural planning utilizing multi-modality imaging training is increasingly recognized as invaluable for procedural accuracy. Left atrial appendage occlusion (LAAO) is one such procedure in which complications such as device leak, cardiac injury, and device embolization can be decreased substantially with incorporation of physician driven imaging and digital tools. We discuss the benefits of cardiac CT and 3D printing in preprocedural planning for the Heart Team, as well as novel applications by physicians of intraprocedural 3D angiography and dynamic fusion imaging. Furthermore, incorporation of computational modeling and artificial intelligence (AI) may yield promise. For optimal patient-centric procedural success, we advocate for standardized preprocedural imaging planning by physicians within the Heart Team as an essential part of LAAO.

Pre-cath Laboratory Planning for Left Atrial Appendage Occlusion - Optional or Essential?

In the wake of rapid advancement in cardiovascular procedural technologies, physician-led preprocedural planning utilizing multi-modality imaging training is increasingly recognized as invaluable for procedural accuracy. Left atrial appendage occlusion (LAAO) is one such procedure in which complications such as device leak, cardiac injury, and device embolization can be decreased substantially with incorporation of physician driven imaging and digital tools. We discuss the benefits of cardiac CT and 3D printing in preprocedural planning for the Heart Team, as well as novel applications by physicians of intraprocedural 3D angiography and dynamic fusion imaging. Furthermore, incorporation of computational modeling and artificial intelligence (AI) may yield promise. For optimal patient-centric procedural success, we advocate for standardized preprocedural imaging planning by physicians within the Heart Team as an essential part of LAAO.

Technical Recommendations for Real-Time Echocardiography and Fluoroscopy Imaging Fusion in Catheter-Based Mitral Valve Paravalvular Leak and Other Procedures

Widespread catheter-based interventions for structural heart disease have overtaken the treatment of paravalvular leaks (PVL). Multimodality imaging techniques play a crucial role in accurate diagnosis, procedure planning and performance. However, PVL closure is often technically challenging due to the complex anatomy of the defects and their relation to surrounding anatomical structures. The application of echocardiography and fluoroscopy imaging fusion (EFF) may simplify challenging imaginative three-dimensional reconstruction of the intracardiac anatomy and facilitate the procedure. To master new technology, personnel must make cognitive changes, overcome a learning curve, and obtain adequate theoretical knowledge. Main aim of this manuscript is to present basic recommendations for EFF application in practice, alongside, each scenario is supported by technically challenging clinical examples. We may conclude that our manuscript may provide useful information for physicians on EEF application in clinical practice.

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.

EchoNavigator® technology facilitates transapical mitral paravalvular leak closure: a case report

Background

Catheter-based closure has emerged as a less invasive alternative to surgery in high-risk patients with paravalvular leak (PVL) and clinically significant regurgitation with feasibility and efficacy demonstrated in multiple studies.

Case summary

A 72-year-old female with a past history of long-standing rheumatic heart disease underwent mechanical mitral valve replacement in 2008. Ten years later, redo surgery was performed due to a worsening mitral PVL and the leakage was closed by direct pledget-supported sutures, preserving the mechanical valve. She was recently admitted again for haemolytic anaemia and congestive heart failure (New York Heart Association Classes III-IV) due to a recurrent mitral PVL. We report our initial clinical experience using a novel software solution (EchoNavigator^®-system) for intuitive guidance during a catheter-based transapical mitral PVL closure.

Discussion

Transapical mitral PVL closure with a specifically designed device demonstrated in our case to be a better option than redo surgery. Recently introduced fusion imaging modalities enhanced visualization of soft tissue anatomy and device location improving enormously the results of this challenging intervention.

Real-time intraoperative co-registration of transesophageal echocardiography with fluoroscopy facilitates transcatheter mitral valve-in-valve implantation in cases of invisible degenerated bioprosthetic valves

OBJECTIVES

Transcatheter mitral valve-in-valve (TMViV) implantation is an alternative treatment to surgery for high-risk patients with degenerated bioprosthetic mitral valves. Some types of bioprostheses are fluoroscopically translucent, resulting in an 'invisible' target deployment area. In this study, we describe the feasibility and outcomes of this procedure using intraoperative fusion of transoesophageal echocardiography (TEE) and live fluoroscopy to facilitate valve deployment in cases of invisible bioprosthetic valves.

METHODS

We reviewed all TMViV implantations at our centre from July 2014 to July 2019. Patient, procedure and outcome details were compared between those with a visible bioprosthesis (N = 22) to those with an invisible one (N = 12). Intra-operative TEE and live Fluoroscopy co-registration were used for real-time guidance for all invisible targets.

RESULTS

All valve implantations were completed successfully in both groups without cardiovascular injury, valve migration or left ventricular outflow-tract obstruction. Technical success was 100% in both groups. One-year survival was 83% [95% confidence interval (CI) 70-96] for the entire cohort, with 79% (95% CI 63-100) survival for the visible group and 92% (95% CI 77-100) for the invisible group. Probability of 1-year survival free from mitral valve reintervention, significant valve dysfunction, stroke or myocardial infraction was 78% (95% CI 63-93) for all patients whereby the probability was 72% (95% CI 54-97) in the visible group and 80% (95% CI 59-100) for the invisible group.

CONCLUSIONS

The use of intraoperative TEE and live fluoroscopy image fusion facilitates accurate TMViV among patients with a fluoroscopically invisible target-landing zone.

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

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

3D-XGuide: open-source X-ray navigation guidance system

PURPOSE

With the growing availability and variety of imaging modalities, new methods of intraoperative support have become available for all kinds of interventions. The basic principles of image fusion and image guidance have been widely adopted and are commercialized through a number of platforms. Although multimodal systems have been found to be useful for guiding interventional procedures, they all have their limitations. The integration of more advanced guidance techniques into the product functionality is, however, not easy due to the proprietary solutions of the vendors. Therefore, the purpose of this work is to introduce a software system for image fusion, real-time navigation, and working points documentation during transcatheter interventions performed under X-ray (XR) guidance.

METHODS

An interactive software system for cross-modal registration and image fusion of XR fluoroscopy with CT or MRI-derived anatomic 3D models is implemented using Qt application framework and VTK visualization pipeline. DICOM data can be imported in retrospective mode. Live XR data input is realized by a video capture card application interface.

RESULTS

The actual software release offers a graphical user interface with basic functionality including data import and handling, calculation of projection geometry and transformations between related coordinate systems, rigid 3D-3D registration, and template matching-based tracking and motion compensation algorithms in 2D and 3D. The link to the actual software release on GitHub including source code and executable is provided to support independent research and development in the field of intervention guidance.

CONCLUSION

The introduced system provides a common foundation for the rapid prototyping of new approaches in the field of XR fluoroscopic guidance. As a pure software solution, the developed system is potentially vendor-independent and can be easily extended to be used with the XR systems of different manufacturers.

Fusion imaging in interventional cardiology

The number and complexity of percutaneous interventions for the treatment of structural heart disease has increased in clinical practice in parallel with the development of new imaging technologies, in order to render these interventions safer and more accurate. Complementary imaging modalities are commonly used, but they require additional mental reconstruction and effort by the interventional team. The concept of fusion imaging, where two different modalities are fused in real time and on a single monitor, aims to solve these limitations. This is an important tool to guide percutaneous interventions, enabling a good visualization of catheters, guidewires and devices employed, with enhanced spatial resolution and anatomical definition. It also allows the marking of anatomical reference points of interest for the procedure. Some studies show decreased procedural time and total radiation dose with fusion imaging; however, there is a need to obtain data with more robust scientific methodology to assess the impact of this technology in clinical practice. The aim of this review is to describe the concept and basic principles of fusion imaging, its main clinical applications and some considerations about the promising future of this imaging technology.

Novel Use of Echo Fusion and Cardiac Computed Tomographic Imaging Guidance for Percutaneous Paravalvular Leak Closure

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Echo fusion overlays echocardiographic cardiac structures over fluoroscopy.

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Echo fusion provides “real-time” feedback during complicated percutaneous procedures.

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Echo fusion and 3D TEE imaging can be used to localize PVLs and guide intervention.

TAVR-related echocardiographic assessment - status quo, challenges and perspectives

Transcatheter aortic valve replacement (TAVR) is an emerging and a well-established procedure for high-risk and inoperable patients worldwide. Recent studies revealed furthermore that TAVR is equal or even superior to surgical valve replacement in intermediate risk patients. Therefore, a successful procedure is not only dependent on precise preprocedural patient selection but also on careful intraprocedural multimodal imaging guidance and adequate postprocedural follow-up. Up to date, 2D/3D transthoracic and/or transoesophageal echocardiography is an easy and goal-oriented tool for periprocedural TAVR-assessment regarding annulus measurements, cardiac function and concomitant valve diseases. Further procedural success is directly related to prevention of severe early and late complications. Thus, a careful intra- and postprocedural echocardiographic guidance is crucial to evaluate prosthetic function, position and its haemodynamic implication and changes in the integrity of the left ventricle during intra- and postprocedural management. We explored the role of echocardiography for pre-, intra- and postprocedural TAVR-assessment, illustrated by cases and possible algorithms, in a comprehensive literature review. Furthermore, we describe the role of fusion imaging, that is, real-time fusion of transoesophageal echocardiography and fluoroscopy (EchoNavigator Release System^® I and II) during TAVR.

Applications of three-dimensional transesophageal echocardiography in congenital heart disease

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

A new low-cost method of virtual cardiac dissection of computed tomographic datasets

Computed tomography has an established role in the evaluation of a variety of cardiac disorders, including congenital heart diseases. The current generation of high-speed scanners produces volumetric data at low doses of radiation. The interpretation of cardiac anatomy, however, is generally limited to multiplanar assessment of two-dimensional images. The volume rendering technique provides an excellent three-dimensional demonstration of external morphology but offers little information about the intracardiac anatomy. The alternative approach of virtual cardiac dissection, which is a modification of volume rendering, on the other hand, provides crucial insights regarding the intracardiac anatomy. At present, virtual cardiac dissection requires expensive software packages. These software packages are not available in all countries, thus limiting its use in routine clinical care. We present here the details of a newly developed technique that permits virtual cardiac dissection using a personal computer and open-source software. Our technique involves no additional cost and can be achieved in the comfort of the office or operating room of the cardiologist, radiologist, or cardiac surgeon. This enhanced three-dimensional visualization of intracardiac anatomy will surely improve the understanding of the morphological details of both normal and malformed hearts. In addition, by permitting assessment in projections with which modern-day cardiologists and cardiac surgeons are conversant, it is likely to improve clinical decision-making. We illustrate here its potential utility in the morphologic assessment of the atrial septum and its deficiencies, along with malformations of the ventricular outflow tracts, including common arterial trunk.

Innovative interventional catheterization techniques for congenital heart disease

Since 1929, when the first cardiac catheterization was safely performed in a human by Dr. Werner Forssmann (on himself), there has been a rapid progression of cardiac catheterization techniques and technologies. Today, these advances allow us to treat a wide variety of patients with congenital heart disease using minimally invasive techniques; from fetus to infants to adults, and from simple to complex congenital cardiac lesions. In this article, we will explore some of the exciting advances in cardiac catheterization for the treatment of congenital heart disease, including transcatheter valve implantation, hybrid procedures, biodegradable technologies, and magnetic resonance imaging (MRI)-guided catheterization. Additionally, we will discuss innovations in imaging in the catheterization laboratory, including 3D rotational angiography (3DRA), fusion imaging, and 3D printing, which help to make innovative interventional approaches possible.

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.

Innovation in 3D Echocardiographic Imaging

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

Adjuncts to transcatheter aortic valve implantation

INTRODUCTION

The appreciable rise in percutaneous valve procedures has been pursued by a wave of development in advanced technology to help guide straightforward, streamlined and safe intervention. This review article aims to highlight the adjunctive devices, tools and techniques currently used in transcatheter aortic valve implantation procedures to avoid potential pitfalls. Areas covered: The software and devices featured here are at the forefront of technological advances, most of which are not yet in widespread use. These products have been discussed in national and international structural intervention conferences and the authors felt it important to showcase particularly well designed adjuncts that improve procedural efficacy and safety. Whilst vascular pre-closure systems are used routinely and are an integral part of these complex cardiovascular procedures, these have been well summarised elsewhere and are beyond the scope of this article. Expert commentary: The rising volume of patients with aortic stenosis who are treatable with TAVI means that this exponential increase in procedures must be accompanied by a steady decline in procedural complications. This section provides an overview of our current perspective, and what we feel the direction of travel will be.

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.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Hybrid Imaging in the Catheter Laboratory: Real-time Fusion of Echocardiography and Fluoroscopy During Percutaneous Structural Heart Disease Interventions

Percutaneous catheter-based techniques for the treatment of structural heart disease are becoming more complex, and current imaging techniques have limitations: while fluoroscopy gives poor visualisation of cardiac anatomical structures, echocardiography is limited in its ability to detect the position of catheters and devices. The EchoNavigator® (Philips) live image guidance tool is a novel system that integrates real-time echocardiography with fluoroscopic X-ray imaging, optimising the guidance and positioning of devices. Use of the EchoNavigator system facilitates improved understanding of anatomical structures while showing enhanced visualisation of catheter and device movements. Early clinical experience suggests that the technology is feasible and safe, and provides enhanced understanding of the relationship between soft tissue anatomy and catheter devices in structural heart disease. The use of the EchoNavigator system can improve the confidence of interventional cardiologists in the targeting and positioning of devices in percutaneous interventions in structural heart disease, and has the potential to reduce procedural time, reduce the dosage of contrast and radiation and increase safety in the performance of procedural steps.

The Changing Paradigm in the Treatment of Structural Heart Disease and the Need for the Interventional Imaging Specialist

Percutaneous interventions in structural heart diseases are emerging rapidly. The variety of novel percutaneous treatment approaches and the increasing complexity of interventional procedures are associated with new challenges and demands on the imaging specialist. Standard catheterisation laboratory imaging modalities such as fluoroscopy and contrast ventriculography provide inadequate visualisation of the soft tissue or three-dimensional delineation of the heart. Consequently, additional advanced imaging technology is needed to diagnose and precisely identify structural heart diseases, to properly select patients for specific interventions and to support fluoroscopy in guiding procedures. As imaging expertise constitutes a key factor in the decision-making process and in the management of patients with structural heart disease, the sub-speciality of interventional imaging will likely develop out of an increased need for high-quality imaging.