First-in-Human Percutaneous Circumferential Annuloplasty for Secondary Tricuspid Regurgitation

An Animal Model of Functional Tricuspid Regurgitation by Leaflet Tethering Using Image-Guided Chordal Encircling Snares

Several interventional therapies are in development to treat functional tricuspid regurgitation. Most have failed to achieve adequate efficacy, as animal models of this lesion are lacking. We developed a new image-guided technique in swine, by tethering the tricuspid valve chordae using echo-guided chordal encircling snares. Five swine underwent baseline echocardiographic assessment of tricuspid valve function, followed by echo-guided placement of snares that encircle the chordae inserting into the anterior and posterior tricuspid valve leaflets. Tethering these snares and stabilizing them on the right ventricle caused the regurgitant fraction to increase from 8.48±5.38% to 48.76±12.5%, and the valve tenting area to increase from 60.26±52.19 to 160.9±86.92 mm2. Image-guided chordal encircling snares could reproducibly induce clinically significant levels of functional tricuspid regurgitation and create a valve geometry like that seen in patients, providing a new animal model for use to study novel interventional devices.

Valvular Heart Failure due to Tricuspid Regurgitation: Surgical and Transcatheter Management Options

Given the independent association of mortality with higher grades of tricuspid regurgitation severity, there is an increasing interest in improving the outcomes of this prevalent valvular heart disease. A new classification of tricuspid regurgitation etiology allows for an improved understanding of different pathophysiologic forms of the disease, which may determine the appropriate management strategy. Current surgical outcomes remain suboptimal and multiple transcatheter device therapies are currently under investigation to give high and prohibitive surgical risk patients treatment options beyond medical therapy.

New therapeutic approach for tricuspid regurgitation: Transcatheter tricuspid valve replacement or repair

The tricuspid valve is a complex structure with normal function dependent on the leaflet morphology, right atrial and annular dynamics, and right ventricular and chordal support. Thus, the pathophysiology of tricuspid regurgitation (TR) is equally complex and current medical and surgical management options are limited. Transcatheter devices are currently being investigated as possible treatment options with lower morbidity and mortality than open surgical procedures. These devices can be divided by their implant location/mechanism of action: leaflet approximation devices, annuloplasty devices, orthotopic valve implants, and heterotopic valve implants. The current review will discuss each class of transcatheter device therapy, and further delve into the current understanding of who and when to treat. Finally, we will include a brief discussion of the future of device and surgical therapy trials for TR and the remaining questions to answer about this complex disease process.

Multimodality Imaging in Valvular Structural Interventions

Structural valvular interventions have skyrocketed in the past decade with new devices becoming available and indications for patients who would previously have been deemed inoperable. Furthermore, while echocardiography is the main imaging tool and the first line for patient screening, cardiac magnetic resonance and CT are now essential tools in pre-planning and post-procedural follow-up. This review aims to address imaging modalities and their scope in aortic, mitral and tricuspid structural valvular interventions, including multimodality imaging. Pulmonary valve procedures, which are mostly carried out in patients with congenital problems, are discussed. This article presents a guide on individualised imaging approcahes on each of the available interventional procedures.

Transcatheter tricuspid valve interventions: Current status and future perspectives

The development of transcatheter therapies to treat valvular heart diseases has changed the rules of the game, particularly in the case of aortic stenosis and mitral regurgitation. In the last years, the tricuspid valve has also been the focus of these percutaneous techniques for several reasons: (1) tricuspid regurgitation is a frequent disease associated with poor clinical outcomes in spite of medical treatment, leading to end-stage right ventricular heart failure, (2) surgical tricuspid valve repair or replacement has been the treatment of choice for patients with tricuspid valve disease, but high mortality rates for isolated surgical tricuspid valve intervention have been reported in the literature, and (3) most patients with tricuspid pathology are ultimately denied cardiac surgery because of their comorbidity burden. Thus, in this context the development of less invasive catheter-based therapies would be of high clinical relevance. The present review provides an overview regarding the framework of chronic tricuspid regurgitation transcatheter therapeutic options, summarizes the transcatheter systems under clinical use or clinical evaluation with their technical features, and describes the updated current evidence in this challenging and evolving field.

Challenges and future perspectives of transcatheter tricuspid valve interventions: adopt old strategies or adapt to new opportunities?

Tricuspid regurgitation (TR) is a highly prevalent valvular heart disease and is associated with an increased risk of cardiovascular events and death at long-term follow-up. Functional TR accounts for over 90% of TR and is mainly due to annular or right ventricular dilatation. Most often, TR is observed in patients with left-sided valvular heart disease (with or without previous surgical correction) and pulmonary hypertension. Isolated TR is less frequent, though burdened by high surgical mortality. This, together with an incomplete understanding of the disease, has brought to a significant undertreatment in spite of the growing evidence of the impact of severe TR on mortality. Moreover, uncertainties about the appropriate timing for intervention and the predictors of procedural success have contributed to limit TR treatment. Transcatheter tricuspid valve replacement or repair interventions represent novel and less invasive alternatives to surgery and have shown early promising results. The purpose of this review is to provide a complete and updated overview of TR pathology with a special focus on current percutaneous treatment options, future challenges and directions.

Transcatheter treatment for tricuspid valve disease

Approximately 4% of subjects aged 75 years or more have clinically relevant tricuspid regurgitation (TR). Primary TR results from anatomical abnormality of the tricuspid valve apparatus and is observed in only 8-10% of the patients with tricuspid valve disease. Secondary TR is more common and arises as a result of annular dilation caused by right ventricular enlargement and dysfunction as a consequence of pulmonary hypertension, often caused by left-sided heart disease or atrial fibrillation. Irrespective of its aetiology, TR leads to volume overload and increased wall stress, both of which negatively contribute to detrimental remodelling and worsening TR. This vicious circle translates into impaired survival and increased heart failure symptoms in patients with and without reduced left ventricular ejection fraction. Interventions to correct TR are underutilised in daily clinical practice owing to increased surgical risk and late patient presentation. The recently introduced transcatheter tricuspid valve interventions aim to address this unmet need. Dedicated expertise and an interdisciplinary Heart Team evaluation are essential to integrate these new techniques successfully and select patients. The present article proposes a standardised approach to evaluate patients with TR who may be candidates for transcatheter interventions. In addition, a state-of-the-art review of the available transcatheter therapies, the main criteria for patient and device selection, and information concerning the remaining uncertainties are provided.