Atrial secondary tricuspid regurgitation: pathophysiology, definition, diagnosis, and treatment.

Atrial secondary tricuspid regurgitation (A-STR) is a distinct phenotype of secondary tricuspid regurgitation with predominant dilation of the right atrium and normal right and left ventricular function. Atrial secondary tricuspid regurgitation occurs most commonly in elderly women with atrial fibrillation and in heart failure with preserved ejection fraction in sinus rhythm. In A-STR, the main mechanism of leaflet malcoaptation is related to the presence of a significant dilation of the tricuspid annulus secondary to right atrial enlargement. In addition, there is an insufficient adaptive growth of tricuspid valve leaflets that become unable to cover the enlarged annular area. As opposed to the ventricular phenotype, in A-STR, the tricuspid valve leaflet tethering is typically trivial. The A-STR phenotype accounts for 10%-15% of clinically relevant tricuspid regurgitation and has better outcomes compared with the more prevalent ventricular phenotype. Recent data suggest that patients with A-STR may benefit from more aggressive rhythm control and timely valve interventions. However, little is mentioned in current guidelines on how to identify, evaluate, and manage these patients due to the lack of consistent evidence and variable definitions of this entity in recent investigations. This interdisciplinary expert opinion document focusing on A-STR is intended to help physicians understand this complex and rapidly evolving topic by reviewing its distinct pathophysiology, diagnosis, and multi-modality imaging characteristics. It first defines A-STR by proposing specific quantitative criteria for defining the atrial phenotype and for discriminating it from the ventricular phenotype, in order to facilitate standardization and consistency in research.

How to Image and Manage Prosthesis-Related Complications After Transcatheter Aortic Valve Replacement.

PURPOSE OF REVIEW: In this review, we provide an overview of potential prosthesis - related complications after transcatheter aortic valve replacement, their incidences, the imaging modalities best suited for detection, and possible strategies to manage these complications. RECENT FINDINGS: Therapy for severe aortic valve stenosis requiring intervention has increasingly evolved toward transcatheter aortic valve replacement over the past decade, and the number of procedures performed has increased steadily in recent years. As more and more centers favor a minimalistic approach and largely dispense with general anesthesia and intra-procedural imaging by transesophageal echocardiography, post-procedural imaging is becoming increasingly important to promptly detect dysfunction of the transcatheter valve and potential complications. Complications after transcatheter aortic valve replacement must be detected immediately in order to initiate adequate therapeutic measures, which require a profound knowledge of possible complications that may occur after transcatheter aortic valve replacement, the imaging modalities best suited for detection, and available treatment options.

State of the Art: Transcatheter Edge-to-Edge Repair for Complex Mitral Regurgitation.

Transcatheter edge-to-edge mitral valve repair has revolutionized the treatment of primary and secondary mitral regurgitation. The landmark EVEREST (Endovascular Valve Edge-to-Edge Repair Study) and COAPT (Clinical Outcomes Assessment of the MitraClip Percutaneous Therapy for High Surgical Risk Patients) trials included only clinically stable patients with favorable mitral valve anatomy for edge-to-edge repair. However, since its initial commercial approval in the United States, growing operator experience, device iterations, and improvements in intraprocedural imaging have led to an expansion in the use of transcatheter edge-to-edge repair to more complex mitral valve pathologies and clinical scenarios, many of which were previously considered contraindications for the procedure. Because patients with prohibitive surgical risk are often older and present with complex mitral valve disease, knowledge of the potential effectiveness, versatility, and technical approach to a broad range of anatomy is clinically relevant. In this review the authors examine the current experience with mitral valve transcatheter edge-to-edge repair in various pathologies and scenarios that go well beyond the EVEREST II trial inclusion criteria.

State-of-the-Art Review: Anatomical and Imaging Considerations During Transcatheter Tricuspid Valve Repair Using an Annuloplasty Approach.

Transcatheter techniques for the treatment of tricuspid regurgitation (TR) are being more frequently used and several new devices are in development. Since 90% of patients with TR have secondary TR, catheter based systems which reduce the dilated tricuspid annulus area are of particular interest. In order to perform an annuloplasty procedure effectively and safely, knowledge about the anatomy of the tricuspid valve apparatus and especially of the annulus in relation to the important neighboring structures such as the aortic root, the RCA, the electrical pathways and the CS is fundamental. In addition, comprehensive understanding of the device itself, the delivery system, its maneuverability and the individual procedural steps is required. Furthermore, the use of multi-modality imaging is important. For each step of the procedure the appropriate imaging modality as well as the optimal; imaging planes are crucial to provide the necessary information to best guide the individual procedural step.

Myxomatous Mitral Valve Disease with Mitral Valve Prolapse and Mitral Annular Disjunction: Clinical and Functional Significance of the Coincidence.

The morphological changes that occur in myxomatous mitral valve disease (MMVD) involve various components, ultimately leading to the impairment of mitral valve (MV) function. In this context, intrinsic mitral annular abnormalities are increasingly recognized, such as a mitral annular disjunction (MAD), a specific anatomical abnormality whereby there is a distinct separation between the mitral annulus and the left atrial wall and the basal portion of the posterolateral left ventricular myocardium. In recent years, several studies have suggested that MAD contributes to myxomatous degeneration of the mitral leaflets, and there is growing evidence that MAD is associated with ventricular arrhythmias and sudden cardiac death. In this review, the morphological characteristics of MAD and imaging tools for diagnosis will be described, and the clinical and functional aspects of the coincidence of MAD and myxomatous MVP will be discussed.

Why Follow-up Examinations After Left Atrial Appendage Closure Are Important: Detection of Complications During Follow-up and How to Deal with Them.

PURPOSE OF REVIEW: Device-related thrombus (DRT) formation and incomplete left atrial appendage closure (LAAC) are the two major complications that can occur after LAAC and can potentially limit the success of such a procedure. This review discusses the incidence, clinical and/or prognostic significance, detection methods, treatment options, and potential strategies to prevent these complications. RECENT FINDINGS: It has recently been proven that the presence of a DRT represents an independent predictor for ischemic stroke after LAAC. Continued need for anticoagulation due to incomplete LAAC is clinically relevant to the patient. The appearances of a DRT or an incompletely closed LAA after a LAAC procedure are not rare complications. Due to the clinical and/or prognostic significance of these complications, it is important to detect them in a timely manner during follow-up by using the appropriate diagnostic imaging techniques. Since a DRT is associated with an increased risk of stroke, the therapy should be aggressive. In the case of incomplete LAA closure, an additional closure device may be used to complete occlusion and avoid lifelong anticoagulation therapy.

Degenerative Mitral Regurgitation: Assessment, Physical Examination, and Imaging.

PURPOSE OF REVIEW: In this review, we provide a comprehensive approach to assess degenerative mitral regurgitation. RECENT FINDINGS: In the evaluation of MR, it is important to differentiate between primary (degenerative/organic) MR in which an intrinsic mitral valve lesion(s) is responsible for the occurrence of MR and secondary (functional) MR where the mitral valve is structurally normal, but alterations of the left ventricular geometry cause deterioration of the MV apparatus. Advanced imaging modalities, foremost two-dimensional and three-dimensional echocardiography, are essential for this determination. In the evaluation of degenerative MR, the exact mechanism, the extent of the disease, associated valve lesions, the grade of mitral regurgitation severity, and hemodynamic consequences require careful assessment in order to provide patients with appropriate monitoring and treatment.

Aortic Regurgitation.

PURPOSE OF REVIEW: Aortic regurgitation (AR) is a common form of valvular disease which is characterized by reflux of blood from the aorta into the left ventricle (LV) during diastole. AR results from various etiologies, affecting the aortic valve cusps or the aortic root. The clinical presentation of patients with AR depends on the severity of the regurgitation and differs whether AR develops acutely or if it progresses over a prolonged period, allowing the cardiac chambers to adapt. Echocardiography is the primary method to determine the etiology of AR and to define its severity. We review the current data regarding the diagnosis and treatment of AR. RECENT FINDINGS: No single parameter is sufficient to determine AR severity; thus, an integrative, multi-parametric approach is required. Echocardiography is key for imaging the aortic valve morphology and flow as well as aortic root and ascending aorta. Determining LV ejection fraction and dimensions is essential for patient management and optimizing timing for intervention. Three-dimensional (3D) echocardiography is useful in the evaluation of AR etiology and severity. The use of Trasncatheter aortic valve replacement (TAVR) has emerged as an alternative to surgery in patients at high operative risk. The diagnosis and management of AR requires a comprehensive approach and routine clinical and echocardiographic follow-up. Surgical or percutaneous therapy is indicated when symptoms develop and in those who have LV dysfunction or LV dilation.

Rheumatic Mitral Valve Stenosis: Diagnosis and Treatment Options.

PURPOSE OF REVIEW: This review provides an update on rheumatic mitral stenosis. Acute rheumatic fever (RF), the sequela of group A ß-hemolytic streptococcal infection, is the major etiology for mitral stenosis (MS). RECENT FINDINGS: While the incidence of acute RF in the Western world had substantially declined over the past five decades, this trend is reversing due to immigration from non-industrialized countries where rheumatic heart disease (RHD) is higher. Pre-procedural evaluation for treatment of MS using a multimodality approach with 2D and 3D transthoracic and transesophageal echo, stress echo, cardiac CT scanning, and cardiac MRI as well as hemodynamic assessment by cardiac catheterization is discussed. The current methods of percutaneous mitral balloon commissurotomy (PMBC) and surgery are also discussed. New data on long-term follow-up after PMBC is also presented. For severe rheumatic MS, medical therapy is ineffective and definitive therapy entails PMBC in patients with suitable morphological mitral valve (MV) characteristics, or surgery. As procedural outcomes depend heavily on appropriate case selection, definitive imaging and interpretation are crucial. It is also important to understand the indications as well as morphological MV characteristics to identify the appropriate treatment with PMBC or surgery.

Imaging for Mitral Interventions: Methods and Efficacy.

The mitral valve (MV) is a complex and intricate structure. With the development of transesophageal echocardiography in the 1990s, it became possible to evaluate MV anatomy and function in real time during surgical procedures. Subsequently, new surgical and percutaneous techniques for MV repair as well as replacement have evolved. Development of 3-dimensional and intracardiac echocardiography, as well as computed tomography, cardiac resonance imaging, and most recently fusion imaging, have paved the way for a more comprehensive evaluation of the MV as well as for the planning of percutaneous MV procedures such as balloon valvuloplasty, paravalvular mitral leak closure, percutaneous edge-to-edge repair, transcatheter MV annuloplasty, artificial chord implantation, and transcatheter MV replacement. The applicability and use of the various imaging modalities for the assessment and guidance of therapy for MV disorders is discussed in this paper.

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.

Percutaneous interventions for left atrial appendage exclusion: options, assessment, and imaging using 2D and 3D echocardiography.

Percutaneous left atrial appendage (LAA) exclusion is an evolving treatment to prevent embolic events in patients with nonvalvular atrial fibrillation. In the past few years multiple percutaneous devices have been developed to exclude the LAA from the body of the left atrium and thus from the systemic circulation. Two- and 3-dimensional transesophageal echocardiography (TEE) is used to assess the LAA anatomy and its suitability for percutaneous closure to select the type and size of the closure device and to guide the device implantation procedure in conjunction with fluoroscopy. In addition, 2- and 3-dimensional TEE is also used to assess the effectiveness of device implantation acutely and on subsequent follow-up examination. Knowledge of the implantation options that are currently available along with their specific characteristics is essential for choosing the appropriate device for a given patient with a specific LAA anatomy. We present the currently available LAA exclusion devices and the echocardiographic imaging approaches for evaluation of the LAA before, during, and after LAA occlusion.

The evolution of percutaneous mitral valve repair therapy: lessons learned and implications for patient selection.

Mitral regurgitation (MR) is the most common valve disease in the United States. However, a significant number of patients are denied surgery due to increased age, poor ventricular function, or associated comorbidities, putting them at high risk for adverse events. Moreover, the benefit of surgery for MR is unclear in patients with functional (secondary) MR. Recently, percutaneous repair of the mitral valve with a particular device (MitraClip, Abbott, Menlo Park, California) has emerged as a novel therapeutic option for patients with secondary MR or those deemed to be high risk for surgery. We review data from its initial concept through clinical trials and current data available from several registries. We focused on lessons learned regarding adequate patient selection, along with current and future perspectives on the use of device therapy for the treatment of MR.

The left atrial appendage: anatomy, function, and noninvasive evaluation.

The left atrial appendage (LAA) is a finger-like extension originating from the main body of the left atrium. Atrial fibrillation (AF) is the most common clinically important cardiac arrhythmia, occurring in approximately 0.4% to 1% of the general population and increasing with age to >8% in those >80 years of age. In the presence of AF thrombus, formation often occurs within the LAA because of reduced contractility and stasis; thus, attention should be given to the LAA when evaluating and assessing patients with AF to determine the risk for cardioembolic complications. It is clinically important to understand LAA anatomy and function. It is also critical to choose the optimal imaging techniques to identify or exclude LAA thrombi in the setting of AF, before cardioversion, and with current and emerging transcatheter therapies, which include mitral balloon valvuloplasty, pulmonary vein isolation, MitraClip (Abbott Laboratories, Abbott Park, Illinois) valve repair, and the implantation of LAA occlusion and exclusion devices. In this review, we present the current data regarding LAA anatomy, LAA function, and LAA imaging using the currently available noninvasive imaging modalities.

Transcatheter valve-in-ring implantation after a failed surgical mitral repair using a transseptal approach and a veno-arterial loop for valve placement.

A failure of a mitral valve repair, which includes the implantation of a mitral annuloplasty ring in the majority of cases, is associated with relevant mortality. Surgery is considered as the standard treatment for these patients. For patients who have an unacceptable high peri-surgical risk a transcatheter valve-in-ring (TVIR) procedure might be an option. Isolated case reports and small case series report on the feasibility of a TVIR implantation in mitral position. We present a case where a 29-mm Edwards Sapien valve was placed in a 32-mm Carpentier Edwards ring. To our knowledge no valve has been implanted so far in this ring size and this is the first case where a veno-arterial loop was used as guide rail for valve implantation and helped considerably to position the valve properly.

Management of mitral stenosis using 2D and 3D echo-Doppler imaging.

Although the prevalence of rheumatic fever is decreasing in developed countries, it still affects numerous areas in the nonindustrialized world. Untreated mitral stenosis (MS) contributes to a significant global morbidity and mortality. Echocardiography is the main diagnostic imaging modality with which to evaluate mitral valve (MV) obstruction and assess the severity and hemodynamic consequences of MS as well as valve morphology. According to current guidelines and recommendations for clinical practice, the severity of MS should not be defined by a single value but assessed by valve areas, mean Doppler gradients, and pulmonary pressures. Transthoracic echocardiography is usually sufficient to grade MS severity and to define the morphology of the valve. Transesophageal echocardiography is used when the valve cannot be adequately assessed with transthoracic echocardiography and to exclude intracardiac thrombi before a percutaneous or surgical intervention. Three-dimensional transthoracic and transesophageal echocardiographic assessment provide more detailed physiological and morphological information. Current definitive treatment for severe MS involves percutaneous mitral balloon valvuloplasty (PMBV) or surgery. The effectiveness of PMBV is related to the etiology of MS, and certain anatomic characteristics tend to predict a more successful outcome for PMBV, whereas other MV structural findings might suggest balloon valvuloplasty to be less likely successful or even contraindicated.

Peri-interventional echo assessment for the MitraClip procedure.

Worldwide, there have been more than 6500 MitraClip procedures performed to treat either functional or degenerative mitral regurgitation (MR). The MitraClip procedure is the only available percutaneous device available to reduce MR by creating a double mitral valve (MV) orifice and decreasing MV annular diameter. As the mitral leaflets cannot be assessed by fluoroscopy, procedural success is dependent upon echocardiographic guidance. In this review, we describe the assessment necessary to determine eligibility for the MitraClip procedure. This includes accurate assessment of MR and detailed analysis of MV morphology by 2D and 3D echocardiography. In addition, each of the intraprocedural steps involved in the deployment of this device and the guidance of these steps by 2D and 3D echo are described in detail, along with the use of echo to detect procedural complications. Thus the focus of this review is on the peri-interventional echocardiographic assessment before, during, and after the MitraClip procedure.

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.