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.

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 Tricuspid Valve.

Even though the tricuspid valve is no longer "forgotten", it still remains poorly understood. In this review, we focus on some controversial and still unclear aspects of tricuspid anatomy as illustrated by noninvasive imaging techniques. In particular, we discuss the anatomical architecture of the so-called tricuspid annulus with its two components (i.e., the mural and the septal annulus), emphasizing the absence of any fibrous "ring" around the right atrioventricular junction. Then we discussed the extreme variability in number and size of leaflets (from two to six), highlighting the peculiarities of the septal leaflet as part of the septal atrioventricular junction (crux cordis). Finally, we describe the similarities and differences between the tricuspid and mitral valve, suggesting a novel terminology for tricuspid leaflets.

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.

Better Take a Second Look: The Fameless Face of Subacute Takotsubo Syndrome.

We have recently published in the journal the case of a 66-year-old female affected by typical Takotsubo syndrome (TTS) with apical ballooning, who presented important novel apical wall thickening despite normalization of left ventricular ejection fraction at a follow-up cardiac magnetic resonance (CMR) 1 month after the acute event. In the absence of significant elevated edema-sensitive T2 values at CMR, this constellation was interpreted as apical hypertrophic cardiomyopathy, initially mimicked by TTS. However, a routine late follow-up echocardiography and CMR after 6 months showed complete resolution of apical wall thickening. "Pseudohypertrophy" caused by transient significant myocardial edema seems to be a more frequent phenotype in the subacute phase of TTS than is yet known, which may cause diagnostic confusion.

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.

Mitral annulus morphometry in degenerative mitral regurgitation phenotypes.

OBJECTIVES: Degenerative mitral regurgitation (DMR) is classified into different phenotypes based on the extent of leaflet degeneration. Our aim is to demonstrate that phenotype complexity predicts the extent of structural abnormalities of mitral annulus (MA). METHODS AND RESULTS: Seventy-five patients with DMR and severe valve regurgitation and 23 patients with normal mitral valve were studied using 3D transesophageal echocardiography. Classification of DMR was done by allocating each 3D echocardiography result under five categories: fibroelastic deficiency (FED), FED+, forme fruste, Barlow's disease Mitral annular disjunction (BD MAD)- or BD MAD+. MA was reconstructed in early systole and in end systole. We tested for a trend toward enlargement and flattening of MA in end systole and for a difference in MA dynamics from early systole to end systole with a worsening of DMR phenotype, in the whole spectrum of subjects ranging from controls to BD MAD+. A significant trend was observed toward larger anteroposterior diameter, intercommissural diameter, annulus circumference, and annulus area (P < .001). A reduction was found in annulus height to commissural width ratio (P = .003): This indicates a progressive MA flattening. Prolapse height and prolapse volume tended to be larger (P < .001). CONCLUSION: Based on the extent of leaflet degeneration, DMR is classified into different phenotypes. As the disease progresses, a related increase in MA size is found, with rounder annular shape, loss of saddle shape, and increase in height and volume of leaflet prolapse. The most pronounced alterations are found in BD MAD+.

Apical Hypertrophic Cardiomyopathy Masked by Takotsubo Syndrome.

We describe the case of a 66-year-old female presented to our emergency department (ER) with acute chest pain and diagnosed with Takotsubo syndrome that initially prevented from suspecting an apical hypertrophic cardiomyopathy at echocardiography.

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.

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.

The challenge of Takotsubo syndrome: heterogeneity of clinical features.

Takotsubo syndrome (TTS) was first described in 1991 as a rare, spontaneous and completely reversible left ventricular regional systolic dysfunction. Today the incidence of TTS is estimated at 2% in patients with an initial diagnosis of acute coronary syndrome (ACS). Notably, the incidence can be as high as 5.9 to 7.5% in female patients. TTS occurs predominantly in postmenopausal women, but both sexes may be affected, at any age. Acute chest pain or dyspnoea is a characteristic symptom of TTS, but initial presentation can also include more severe disease manifestation such as acute heart failure with pulmonary oedema or haemodynamic instability, especially in an in-hospital setting. It is now known that TTS is triggered by not only emotional, but also physical stressors, or a combination of both. Although apical ballooning is the most frequent and typical finding on imaging, different types of TTS have been described, including the midventricular, basal and focal forms. The acute phase of TTS may be complicated by cardiogenic shock, left ventricular outflow tract obstruction, severe mitral valve regurgitation, embolisation of ventricular thrombi and life-threatening ventricular arrhythmias. Furthermore, although originally thought to be a completely reversible condition, the long-term prognosis of TTS is not entirely positive, with a major adverse cardiac and cerebrovascular event (MACCE) rate of 9.9% reported in the InterTAK Registry, the largest series of patients with TTS. The exact aetiology of TTS remains unknown, there are no current treatment guidelines and differential diagnosis from the more frequent ACS entities remains particularly challenging. Overall, TTS remains a poorly understood and under-diagnosed disease, sometimes disguised in clinically atypical presentations. This review presents different TTS cases to illustrate that TTS is a heterogeneous disease.

A broken heart in a broken car.

Takotsubo syndrome (TTS) is still a relatively understudied and often undetected disease. It is usually preceded by emotional or physical triggers. We here report a case of TTS following a car accident. Typical apical ballooning with moderate reduction of left ventricular ejection fraction (LVEF) and increased level of pro-B-type natriuretic peptide (BNP) as well as slightly increased creatine kinase and troponin T values were found in this 76-year-old female patient, 6 h after a car accident. At 10 weeks follow-up, we observed a normalization of regional wall motion, LVEF, electrocardiogram and pro-BNP. TTS is an acute heart failure syndrome and an important differential diagnosis of acute coronary syndrome.

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.