Mitral Annular Disjunction in the Context of Mitral Valve Prolapse: Identifying the At-Risk Patient.

Mitral annular disjunction (MAD), a separation between the left atrium/mitral valve annulus and the left ventricular myocardium, is frequently seen in patients with arrhythmic mitral valve prolapse. Although an association exists between MAD and ventricular arrhythmias, little is known regarding the identification of individuals at high risk. Multimodality imaging including echocardiography, computed tomography, cardiac magnetic resonance, and positron emission tomography can play an important role in both the diagnosis and risk stratification of MAD. Due to a paucity of data, clinical decision making in a patient with MAD is challenging and remains largely empirical. Although MAD itself can be corrected surgically, the prevention and treatment of associated arrhythmias may require medical therapy, catheter ablation, and an implantable cardioverter-defibrillator. Prospective data are required to define the role of implantable cardioverter-defibrillators, targeted catheter ablation, and surgical correction in selected, at-risk patients.

Epidemiology, pathophysiology, diagnosis and management of chronic right-sided heart failure and tricuspid regurgitation. A clinical consensus statement of the Heart Failure Association (HFA) and the European Association of Percutaneous Cardiovascular Interventions (EAPCI) of the ESC.

Right-sided heart failure and tricuspid regurgitation are common and strongly associated with poor quality of life and an increased risk of heart failure hospitalizations and death. While medical therapy for right-sided heart failure is limited, treatment options for tricuspid regurgitation include surgery and, based on recent developments, several transcatheter interventions. However, the patients who might benefit from tricuspid valve interventions are yet unknown, as is the ideal time for these treatments given the paucity of clinical evidence. In this context, it is crucial to elucidate aetiology and pathophysiological mechanisms leading to right-sided heart failure and tricuspid regurgitation in order to recognize when tricuspid regurgitation is a mere bystander and when it can cause or contribute to heart failure progression. Notably, early identification of right heart failure and tricuspid regurgitation may be crucial and optimal management requires knowledge about the different mechanisms and causes, clinical course and presentation, as well as possible treatment options. The aim of this clinical consensus statement is to summarize current knowledge about epidemiology, pathophysiology and treatment of tricuspid regurgitation in right-sided heart failure providing practical suggestions for patient identification and management.

Multimodality Imaging Evaluation to Detect Subtle Right Ventricular Involvement in Patients with Acute Myocarditis and Preserved Left Ventricular Ejection Fraction.

Background: Evaluation of the right ventricle (RV) in patients with acute myocarditis (MY) remains challenging with both 2D transthoracic echocardiography (TTE) and cardiovascular magnetic resonance (CMR). We examined the incremental diagnostic value of CMR feature tracking (FT) to evaluate RV involvement in patients with myocarditis. Methods: We enrolled 54 patients with myocarditis and preserved left ventricle (LV) ejection fraction (EF). The CMR protocol included T2-weighted images for edema detection and late gadolinium enhancement (LGE) images. Global longitudinal strain (GLS) of the left ventricle (LV) and RV free wall strain (CMR-FWS) were obtained with CMR-FT. We identified 34 patients (62%) with inferior and lateral segment (IL-MY) involvement and 20 (38%) noIL-MY in case of any other myocardial segment involved. Here, 20 individuals who underwent CMR for suspected cardiac disease, which was not confirmed thereafter, were considered as the control population. Results: TTE and CMR showed normal RV function in all patients without visible RV involvement at the LGE or T2-weighted sequences. At CMR, LV-GLS values were significantly lower in patients with MY compared to the control group (median -19.0% vs. -21.0%, p = 0.029). Overall, CMR RV-FWS was no different between MY patients and controls (median -21.2% vs. -23.2 %, p = 0.201) while a significant difference was found between RV FWS in IL-MY and noIL-MY (median -18.17% vs. -24.2%, p = 0.004). Conclusions: CMR-FT has the potential to unravel subclinical RV involvement in patients with acute myocarditis, specifically in those with inferior and lateral injuries that exhibit lower RV-FWS values. In this setting, RV deformation analysis at CMR may be effectively implemented for a comprehensive functional assessment.

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.

Imaging assessment of the right atrium: anatomy and function.

The right atrium (RA) is the cardiac chamber that has been least well studied. Due to recent advances in interventional cardiology, the need for greater understanding of the RA anatomy and physiology has garnered significant attention. In this article, we review how a comprehensive assessment of RA dimensions and function using either echocardiography, cardiac computed tomography, and magnetic resonance imaging may be used as a first step towards a better understanding of RA pathophysiology. The recently published normative data on RA size and function will likely shed light on RA atrial remodelling in atrial fibrillation (AF), which is a complex phenomenon that occurs in both atria but has only been studied in depth in the left atrium. Changes in RA structure and function have prognostic implications in pulmonary hypertension (PH), where the increased right ventricular (RV) afterload first induces RV remodelling, predominantly characterized by hypertrophy. As PH progresses, RV dysfunction and dilatation may begin and eventually lead to RV failure. Thereafter, RV overload and increased RV stiffness may lead to a proportional increase in RA pressure. This manuscript provides an in-depth review of RA anatomy, function, and haemodynamics with particular emphasis on the changes in structure and function that occur in AF, tricuspid regurgitation, and PH.

Morphology of Mitral Annular Disjunction in Mitral Valve Prolapse.

Mitral annular disjunction (MAD) is an abnormal insertion of the hinge line of the posterior mitral leaflet on the atrial wall: the mitral annulus shows a separation or "disjunction" between the leaflet-atrial wall junction and the crest of the left ventricle myocardium. This anomaly is often observed in patients with myxomatous mitral valve prolapse. The anatomical substrate of MAD remains unclear for the following reasons: (1) most studies are focused on the association between MAD and arrhythmias, rather than on pathomorphological aspects of MAD; and (2) the complex anatomic architecture of the posterior mitral annulus is often simply described as the posterior segment of a fibrous ring. The aims of this paper are to review the pertinent normal anatomy of the mitral valve and to propose new hypotheses on the morphological nature of MAD.

Multimodality Imaging of the Anatomy of the Aortic Root.

The aortic root has long been considered an inert unidirectional conduit between the left ventricle and the ascending aorta. In the classical definition, the aortic valve leaflets (similar to what is perceived for the atrioventricular valves) have also been considered inactive structures, and their motion was thought to be entirely passive-just driven by the fluctuations of ventricular-aortic gradients. It was not until the advent of aortic valve-sparing surgery and of transcatheter aortic valve implantation that the interest on the anatomy of the aortic root again took momentum. These new procedures require a systematic and thorough analysis of the fine anatomical details of the components of the so-called aortic valve apparatus. Although holding and dissecting cadaveric heart specimens remains an excellent method to appreciate the complex "three-dimensional" nature of the aortic root, nowadays, echocardiography, computed tomography, and cardiac magnetic resonance provide excellent images of cardiac anatomy both in two- and three-dimensional format. Indeed, modern imaging techniques depict the aortic root as it is properly situated within the thorax in an attitudinally correct cardiac orientation, showing a sort of "dynamic anatomy", which admirably joins structure and function. Finally, they are extensively used before, during, and after percutaneous structural heart disease interventions. This review focuses on the anatomy of the aortic root as revealed by non-invasive imaging techniques.

Transcatheter mitral valve interventions: pre-procedural planning and intra-procedural guidance.

Mitral regurgitation is the most prevalent valve disease worldwide. Percutaneous mitral valve interventions are emerging as alternative options for high-risk patients with severe mitral regurgitation not eligible for conventional surgery. Accurate patient selection is based on a detailed pre-procedural multimodality imaging evaluation. Morphology and functional anatomy of the mitral valve should be evaluated to determine the feasibility of treatments and to identify the best therapeutic approach. The procedures are guided by fluoroscopy, transesophageal echocardiography and fusion imaging, ensuring a continuous communication between the interventionalist and the imaging specialist. The present review will cover the pre-procedural planning and the intra-procedural guidance of the most used transcatheter approaches in the setting of native mitral valve regurgitation: edge to edge repair, percutaneous direct and indirect annuloplasty, transapical beating-heart chordal implantation and transcatheter mitral valve replacement.

Imaging for Patient's Selection and Guidance of LAA and ASD Percutaneous and Surgical Closure.

This review comprises 2 main subjects: the percutaneous and surgical closure of the left atrial appendage (LAA) and atrial septal defect (ASD). The aim of the authors was to provide a detailed description of: 1) anatomy of LAA, normal interatrial septum, and the various types of ASD as revealed by noninvasive imaging techniques; 2) preprocedure planning of secundum ASD and LAA percutaneous closure; 3) key steps of the procedural guidance emphasizing the role of 2-dimensional/3-dimensional transesophageal echocardiography; and 4) surgical closure of LAA and ASD.

Anatomy of Mitral Valve Complex as Revealed by Non-Invasive Imaging: Pathological, Surgical and Interventional Implications.

Knowledge of mitral valve (MV) anatomy has been accrued from anatomic specimens derived by cadavers, or from direct inspection during open heart surgery. However, today two-dimensional and three-dimensional transthoracic (2D/3D TTE) and transesophageal echocardiography (2D/3D TEE), computed tomography (CT) and cardiac magnetic resonance (CMR) provide images of the beating heart of unprecedented quality in both two and three-dimensional format. Indeed, over the last few years these non-invasive imaging techniques have been used for describing dynamic cardiac anatomy. Differently from the "dead" anatomy of anatomic specimens and the "static" anatomy observed during surgery, they have the unique ability of showing "dynamic" images from beating hearts. The "dynamic" anatomy gives us a better awareness, as any single anatomic arrangement corresponds perfectly to a specific function. Understanding normal anatomical aspects of MV apparatus is of a paramount importance for a correct interpretation of the wide spectrum of patho-morphological MV diseases. This review illustrates the anatomy of MV as revealed by non-invasive imaging describing physiological, pathological, surgical and interventional implications related to specific anatomical features of the MV complex.

The Intrusive Nature of Epicardial Adipose Tissue as Revealed by Cardiac Magnetic Resonance.

The epicardial adipose tissue (EAT) refers to the deposition of adipose tissue fully enclosed by the pericardial sac. EAT has a complex mixture of adipocytes, nervous tissue, as well as inflammatory, stromal and immune cells secreting bioactive molecules. This heterogeneous composition reveals that it is not a simply fat storage depot, but rather a biologically active organ that appears playing a "dichotomous" role, either protective or proinflammatory and proatherogenic. The cardiac magnetic resonance (CMR) allows a clear visualization of EAT using a specific pulse sequence called steady-state free precession. When abundant, the EAT assumes a pervasive presence not only covering the entire epicardial surface but also invading spaces that usually are almost virtual and separating walls that usually are so close each other to resemble a single wall. To the best of our knowledge, this aspect of cardiac anatomy has never been described before. In this pictorial review, we therefore focus our attention on certain cardiac areas in which EAT, when abundant, is particularly intrusive. In particular, we describe the presence of EAT into: (a) the interatrial groove, the atrioventricular septum, and the inferior pyramidal space, (b) the left lateral ridge, (c) the atrioventricular grooves, and (d) the transverse pericardial sinus. To confirm the reliability in depicting the EAT distribution, we present CMR images side-by-side with corresponding anatomic specimens.

Anatomy of mitral annulus insights from non-invasive imaging techniques.

The mitral annulus (MA) is not a continuous ring of connective tissue from which are suspended mitral leaflets. Instead, it is a much more complex structure made up of a mix of fibrous, muscular, and adipose tissues. MA is a key structure in any type of mitral valve repair and recently it has been targeted for transcutaneous devices. Thus, a deep understanding of MA anatomy has never been more important. Traditionally, cardiac anatomy has been described using anatomic specimens. Currently, sophisticated non-invasive techniques allow imaging of MA with a richness of anatomical details unimaginable only two decades ago. The aim of this review is to provide a better understanding of the peculiar aspects of MA as they are revealed through these imaging techniques and discuss clinical implications related to this complex structure.

3-Dimensional Echocardiography in Imaging the Tricuspid Valve.

Tricuspid regurgitation (TR) is an independent predictor of death. Lately, emerging technologies for the treatment of TR have increased the interest of physicians. Due to the complex 3-dimensional (3D) geometry of the tricuspid valve (TV) and its anterior position in the mediastinum, conventional 2D echocardiography is unsuitable to study the anatomy and pathophysiologic mechanisms of the regurgitant TV. 3D echocardiography has emerged as a very cost-effective imaging modality with which to: 1) visualize the TV anatomy; 2) define the mechanism of TR; 3) measure the size and geometry of the tricuspid annulus; 4) analyze the anatomic relationships between TV apparatus and surrounding cardiac structures; 5) assess volumes and function of the right atrium and ventricle; and 6) plan surgical repair or guide and monitor transcatheter interventional procedures.

Revisiting Anatomy of the Interatrial Septum and its Adjoining Atrioventricular Junction Using Noninvasive Imaging Techniques.

Interest in the anatomy of the interatrial septum (IAS) and its adjoining atrioventricular (AV) junction has risen enormously in the past two decades with the simultaneous evolution of left-sided percutaneous structural heart disease and complex electrophysiologic procedures. These procedures require, in fact, a direct route to the left atrium through the IAS. Thus, a thorough understanding of the complex anatomy of the IAS and AV junction is essential for performing a safe and effective transseptal puncture. There is a large amount of literature carefully describing the anatomy of the IAS and AV junction. These studies are based almost exclusively on anatomic specimens. Conversely, in this review the authors emphasize the role of noninvasive imaging techniques, in particular cardiac magnetic resonance, two- and three-dimensional transesophageal echocardiography, and computed tomography in visualizing specific aspects of the normal IAS and AV junction. Where appropriate, the authors present images side by side, with corresponding anatomic specimens.

Imaging-based tricuspid valve anatomy by computed tomography, magnetic resonance imaging, two and three-dimensional echocardiography: correlation with anatomic specimen.

Interest on tricuspid valve (TV) (and hence in TV anatomy) has increased in the last two decades with the awareness that functional tricuspid regurgitation (FTR) is an insidious disease progressively leading to untreatable right heart failure and eventually to death. Medical therapy may alleviate symptoms, while surgical therapy may improve outcome but it is associated with high mortality and recurrence of significant regurgitation. Nowadays, an increasing number of left valve diseases are successfully treated through a percutaneous transcatheter approach. The negative impact that the untreated FTR may have in these patients has highlighted the necessity of developing transcatheter solutions also for FTR and numerous catheter devices for treating FTR are currently under evaluation. The essential pre-requisite for an effective and safe surgical or transcatheter therapy is a deep knowledge of the normal TV anatomy. In this review, we describe the anatomy of TV and surrounding structures as revealed by computed tomography, cardiac magnetic resonance, 2D/3D transthoracic echocardiography, and 2D/3D transoesophageal echocardiography emphasizing strengths and weaknesses of each of these imaging tools. To confirm the anatomical fidelity of these imaging modalities, where appropriate, the non-invasive images where presented, side-by-side, with corresponding images from anatomic specimens.

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.