Impact of Tricuspid Valve Morphology on Clinical Outcomes After Transcatheter Edge-to-Edge Repair

New Therapeutic Advances in the Management of Tricuspid Valve Regurgitation

Tricuspid regurgitation (TR) is an intricate disorder that has a negative outlook, while surgical treatment is linked to increased mortality. Primary TR occurs due to a structural defect in the tricuspid valve (TV), while secondary TR is a more prevalent condition often associated with pulmonary hypertension, heart failure, and atrial fibrillation. The use of specific surgical procedures to improve TR is limited in everyday clinical practice due to the heightened surgical risk and delayed patient presentation. The development of other transcatheter heart valve procedures has led to a significant increase in transcatheter TV operations, which can be attributed to certain technological advancements. This review aims to provide an updated overview of transcatheter TV procedures, available alternative therapies, and standards for patient selection. It will also highlight the current state of development in this field, which is characterized by rapid progress and numerous ongoing clinical trials.

Anatomical evaluation of a novel echocardiography based tricuspid valve classification in 60 hearts from body donors

OBJECTIVES

This study aimed to provide comprehensive morphological descriptions of the morphology of the tricuspid valve and to evaluate if a novel echocardiography-based tricuspid valve nomenclature can also be understood anatomically.

METHODS

Tricuspid valves of 60 non-embalmed human body donors without a medical history of pathologies or macroscopic malformations of the heart were included. Length, height and surface area of leaflets were measured. The valves were morphologically classified according to a novel echocardiography-based classification, in which 6 types are distinguished: classic 3-leaflet configuration, bicuspid valves, valves with 1 leaflet split into 2 scallops or leaflets and valves with 2 leaflets divided into 2 scallops or leaflets.

RESULTS

We found a true 3-leaflet configuration in only 19 (31.7%) of valves. Five (8.3%) had a 2-leaflet configuration with a fused anterior and posterior leaflet. Of those, 3 had a divided septal leaflet. Four valves (6.7%) had a divided anterior leaflet, 17 (28.3%) had a divided posterior leaflet, 6 (10%) had a divided septal leaflet and 9 (15.0%) had 2 leaflets divided. Overall, 39 (65%) of valves have at least 1 leaflet that is divided. In 22 (36.7%) specimens, the leaflet was divided into true leaflets, and in 17 (28.3%) specimens, the leaflet was divided into scallops. In addition, we could identify 9 (15%) valves having 1 leaflet divided not only in 2 but 3 scallops or leaflets.

CONCLUSIONS

This study provides further anatomical insight for the significant variability in the morphology of the tricuspid valve. By updating the understanding of its morphological characteristics, this study equips clinicians with valuable insights to effectively advance surgical and interventional treatment of tricuspid valves.

Transcatheter Therapy for the Tricuspid Valve: A Focused Review of Edge-to-Edge Repair and Orthotopic Valve Replacement

PURPOSE OF REVIEW

Patients with severe tricuspid regurgitation (TR) are at risk for significant morbidity and mortality. Transcatheter tricuspid valve interventions (TTVI) may offer patients less invasive treatment alternatives to surgery. This review evaluates the most common class of device currently used worldwide to treat TR, tricuspid transcatheter edge-to-edge repair (T-TEER) and orthotopic transcatheter tricuspid valve replacement (TTVR), both of which are now approved in the USA and Europe.

RECENT FINDINGS

The first pivotal randomized clinical trial, TRILUMINATE, demonstrated that T-TEER can safely reduce TR and is associated with improved health status outcomes. However, results of this trial have raised questions about whether this device can provide sufficient TR reduction to impact clinical outcomes. Orthotopic TTVR has recently gained attention with initial data suggesting near-complete TR elimination. The current review examines the technical features and anatomic limitations of the most commonly used devices for T-TEER and orthotopic TTVR, discusses the current clinical data for these devices, and offers a theoretical construct for device selection.

Transthoracic and transoesophageal echocardiography for tricuspid transcatheter edge-to-edge repair: a step-by-step protocol

Tricuspid regurgitation (TR) carries an unfavourable prognosis and often leads to progressive right ventricular (RV) failure. Secondary TR accounts for over 90% of cases and is caused by RV and/or tricuspid annulus dilation, in the setting of left heart disease or pulmonary hypertension. Surgical treatment for isolated TR entails a high operative risk and is seldom performed. Recently, transcatheter edge-to-edge repair (TEER) has emerged as a low-risk alternative treatment in selected patients. Although the experience gained from mitral TEER has paved the way for the technique's adaptation to the tricuspid valve (TV), its anatomical complexity necessitates precise imaging. To this end, a comprehensive protocol integrating 2D and 3D imaging from both transthoracic echocardiography (TTE) and transoesophageal echocardiography (TOE) plays a crucial role. TTE allows for an initial morphological assessment of the TV, quantification of TR severity, evaluation of biventricular function, and non-invasive haemodynamic evaluation of pulmonary circulation. TOE, conversely, provides a detailed evaluation of TV morphology, enabling precise assessment of TR mechanism and severity, and represents the primary method for determining eligibility for TEER. Once a patient is considered eligible for TEER, TOE, alongside fluoroscopy, will guide the procedure in the catheterization lab. High-quality TOE imaging is crucial for patient selection and to achieve procedural success. The present review examines the roles of TTE and TOE in managing patients with severe TR eligible for TEER, proposing the step-by-step protocol successfully adopted in our centre.

Tricuspid Valve Regurgitation: Current Understanding and Novel Treatment Options

Managing patients with severe symptomatic tricuspid regurgitation (TR) remains extremely challenging, with a lack of consensus on when and how to treat it. Tricuspid valve pathology has been disregarded for a very long time because of the established belief that treating left-sided heart diseases would lead to the resolution or significant improvement of TR. Initially considered benign, severe TR has been found to be a strong predictor of prognosis. Despite the increasing prevalence and the disabling nature of this disease, the great majority of patients with clinically significant TR have seldom been considered for structural interventions. Numerous surgical and transcatheter treatment options are now available; however, optimal timing and procedural selection remain crucial aspects influencing outcomes. According to recent evidence in the literature, early referral is associated with good short and long-term outcomes, and various predictors of favorable outcomes following either surgical or transcatheter treatment have been identified. Evaluation by a multidisciplinary heart team with expertise in tricuspid valve disease is of paramount importance to identify adequate treatment for every patient.

Multimodality imaging for transcatheter tricuspid valve repair and replacement

Transcatheter tricuspid intervention is a rapidly evolving field with multiple classes of therapeutic devices currently in development. Procedural success in tricuspid intervention is predicated on appropriate device selection for patient specific anatomy and satisfactory imaging for intra-procedural guidance. This review will outline protocols and methodology for multi-modality imaging assessment of the tricuspid valve and associated structures, with emphasis on anatomic and functional characteristics that determine suitability for each class of tricuspid intervention. Intra-procedural imaging requirements for each class of device, with design and procedural imaging guidance of specific devices, will also be addressed.

1-Year Outcomes of Transcatheter Tricuspid Valve Repair

BACKGROUND

Surgical management of isolated tricuspid regurgitation (TR) is associated with high morbidity and mortality, thereby creating a significant need for a lower-risk transcatheter solution.

OBJECTIVES

The single-arm, multicenter, prospective CLASP TR (Edwards PASCAL TrAnScatheter Valve RePair System in Tricuspid Regurgitation [CLASP TR] Early Feasibility Study) evaluated 1-year outcomes of the PASCAL transcatheter valve repair system (Edwards Lifesciences) to treat TR.

METHODS

Study inclusion required a previous diagnosis of severe or greater TR and persistent symptoms despite medical treatment. An independent core laboratory evaluated echocardiographic results, and a clinical events committee adjudicated major adverse events. The study evaluated primary safety and performance outcomes, with echocardiographic, clinical, and functional endpoints. Study investigators report 1-year all-cause mortality and heart failure hospitalization rates.

RESULTS

Sixty-five patients were enrolled: mean age of 77.4 years; 55.4% female; and 97.0% with severe to torrential TR. At 30 days, cardiovascular mortality was 3.1%, the stroke rate was 1.5%, and no device-related reinterventions were reported. Between 30 days and 1 year, there were an additional 3 cardiovascular deaths (4.8%), 2 strokes (3.2%), and 1 unplanned or emergency reintervention (1.6%). One-year postprocedure, TR severity significantly reduced (P < 0.001), with 31 of 36 (86.0%) patients achieving moderate or less TR; 100% had at least 1 TR grade reduction. Freedom from all-cause mortality and heart failure hospitalization by Kaplan-Meier analyses were 87.9% and 78.5%, respectively. Their New York Heart Association functional class significantly improved (P < 0.001) with 92% in class I or II, 6-minute walk distance increased by 94 m (P = 0.014), and overall Kansas City Cardiomyopathy Questionnaire scores improved by 18 points (P < 0.001).

CONCLUSIONS

The PASCAL system demonstrated low complication and high survival rates, with significant and sustained improvements in TR, functional status, and quality of life at 1 year. (Edwards PASCAL TrAnScatheter Valve RePair System in Tricuspid Regurgitation [CLASP TR] Early Feasibility Study [CLASP TR EFS]; NCT03745313).

Leaflet Morphology and its Implications for Direct Transcatheter Annuloplasty of Tricuspid Regurgitation

BACKGROUND

Leaflet morphology has been associated with treatment success in edge-to-edge repair of tricuspid regurgitation (TR), but the impact on annuloplasty is unclear.

OBJECTIVES

The authors sought to examine the association of leaflet morphology with efficacy and safety of direct annuloplasty in TR.

METHODS

The authors analyzed patients who underwent catheter-based direct annuloplasty with the Cardioband at 3 centers. Leaflet morphology was assessed according to number and location of leaflets by echocardiography. Patients with simple morphology (2 or 3 leaflets) were compared with complex morphology (>3 leaflets).

RESULTS

The study included 120 patients (median age 80 years) with ≥severe TR. A total of 48.3% of patients had a 3-leaflet morphology, 5% a 2-leaflet morphology, and 46.7% had >3 tricuspid leaflets. Baseline characteristics did not differ relevantly between groups except for a higher incidence of torrential TR grade (50 vs 26.6%) in complex morphologies. Postprocedural improvement of 1 (90.6% vs 92.9%) and 2 (71.9% vs 67.9%) TR grades was not significantly different between groups, but patients with complex morphology had more often residual TR ≥3 at discharge (48.2 vs 26.6%; P = 0.014). This difference did not remain significant (P = 0.112) after adjusting for baseline TR severity, coaptation gap, and nonanterior jet localization. Safety endpoints including complications of the right coronary artery, and technical success did not show significant differences.

CONCLUSIONS

Efficacy and safety of transcatheter direct annuloplasty using Cardioband are not affected by leaflet morphology. Assessment of leaflet morphology should be part of procedural planning in patients with TR and might help to individually tailor repair techniques to patient anatomy.

Tricuspid Valve Geometrical Changes in Patients with Functional Tricuspid Regurgitation: Insights from a CT Scan Analysis Focusing on Commissures

BACKGROUND

Cardiac computed tomography (CT) provides important insights into the geometrical configuration of the tricuspid valve (TV). The purpose of the present study was to assess the geometrical changes of TV in patients with functional tricuspid regurgitation (TR) using novel CT scan parameters and to correlate these findings with echocardiography.

METHODS

This single-center study enrolled 86 patients undergoing cardiac CT and divided them into two groups according to the presence or not of severe TR (43 patients with TR ≥ 3+ and 43 controls). The measurements collected were as follows: TV annulus area and perimeter, septal-lateral and antero-posterior annulus diameters, eccentricity, distance between commissures, segment between the geometrical centroid and commissures, and the angles of commissures.

RESULTS

We found a significant correlation between all annulus measurements and the grade of TR, except in regard to angles. TR ≥ 3+ patients had significantly larger TV annulus area and perimeter, larger septal-lateral, and antero-posterior annulus dimensions, as well as larger commissural distance and centroid-commissural distance. In patients with TR ≥ 3+ and controls, the eccentricity index predicted a circular shape and an oval shape of the annulus, respectively.

CONCLUSIONS

These novel CT variables focusing on commissures increase the anatomical understanding of the TV apparatus and the TV geometrical changes in patients with severe functional TR.

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.

Novel Computed Tomography Variables for Assessing Tricuspid Valve Morphology: Results from the TRIMA (Tricuspid Regurgitation IMAging) Study

BACKGROUND

Computed tomography (CT) is the recommended imaging technique for defining the anatomical suitability for current transcatheter technologies and planning tricuspid valve (TV) intervention. The aim of the Tricuspid Regurgitation IMAging (TRIMA) study was to assess the geometrical characteristics of the TV complex using novel CT parameters.

METHODS

This prospective, single-center study enrolled 22 consecutive patients with severe tricuspid regurgitation, who underwent a cardiac CT study dedicated to the right chambers. The following variables were obtained: annulus area and perimeter, septal-lateral and antero-posterior diameters, tenting height, and anatomical regurgitant orifice area. Moreover, the following novel annular parameters were assessed: distance between commissures, distance between TV centroid and commissures, and angles between centroid and commissures.

RESULTS

A significant phasic variability during the cardiac cycle existed for all variables except for eccentricity, angles, and distance between the postero-septal and antero-posterior commissure and distance between the centroid and antero-posterior commissure. There was a significant relationship between the TV annulus area and novel annular parameters, except for annular angles. Additionally, novel annular variables were found to predict the annulus area.

CONCLUSIONS

These novel additional variables may provide an initial platform from which the complexity of the TV annular morphology can continue to be better understood for further improving transcatheter therapies.

Atrial Functional Tricuspid Regurgitation as a Distinct Pathophysiological and Clinical Entity: No Idiopathic Tricuspid Regurgitation Anymore

Functional tricuspid regurgitation (FTR) is a strong and independent predictor of patient morbidity and mortality if left untreated. The development of transcatheter procedures to either repair or replace the tricuspid valve (TV) has fueled the interest in the pathophysiology, severity assessment, and clinical consequences of FTR. FTR has been considered to be secondary to tricuspid annulus (TA) dilation and leaflet tethering, associated to right ventricular (RV) dilation and/or dysfunction (the "classical", ventricular form of FTR, V-FTR) for a long time. Atrial FTR (A-FTR) has recently emerged as a distinct pathophysiological entity. A-FTR typically occurs in patients with persistent/permanent atrial fibrillation, in whom an imbalance between the TA and leaflet areas results in leaflets malcoaptation, associated with the dilation and loss of the sphincter-like function of the TA, due to right atrium enlargement and dysfunction. According to its distinct pathophysiology, A-FTR poses different needs of clinical management, and the various interventional treatment options will likely have different outcomes than in V-FTR patients. This review aims to provide an insight into the anatomy of the TV, and the distinct pathophysiology of A-FTR, which are key concepts to understanding the objectives of therapy, the choice of transcatheter TV interventions, and to properly use pre-, intra-, and post-procedural imaging.

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.

Leaflet Configuration and Residual Tricuspid Regurgitation After Transcatheter Edge-to-Edge Tricuspid Repair

OBJECTIVES

This study aimed to assess the anatomical leaflet variation and investigate its impact on the procedural outcome in patients undergoing transcatheter edge-to-edge tricuspid repair.

BACKGROUND

Tricuspid regurgitation (TR) is associated with a poor prognosis.

METHODS

The study participants were consecutive patients who underwent transcatheter edge-to-edge tricuspid repair with the MitraClip, TriClip, or PASCAL systems from June 2015 to July 2020 at the Bonn Heart Center. The tricuspid leaflet morphologies were imaged using 2-dimensional and 3-dimensional transesophageal echocardiography. The severity of TR was assessed according to the 5-grade scheme. The primary endpoint was residual TR ≥3+ within 30 days.

RESULTS

Of the 145 study participants, 103 (71.1%) participants were categorized as the 3-leaflet configuration, while 42 (28.9%) were categorized as the 4-leaflet configuration. Successful device implantation was achieved in 136 (93.8%) patients, with no statistical difference between the 3-leaflet and 4-leaflet configuration groups. However, compared with patients with a 3-leaflet configuration, patients with 4-leaflet configuration more frequently had residual TR ≥3+ (18.4% vs 38.1%; P = 0.018). In the multivariable model, the 4-leaflet configuration was associated with an increased risk of residual TR ≥3+ (odds ratio: 2.65; 95% CI 1.15-6.10; P = 0.022), independent of baseline TR grade, coaptation gap width, and TR jet location. After 1-year follow-up, compared with patients with residual TR <3+, patients with residual TR ≥3+ had a significantly higher incidence of the composite of all-cause mortality or heart failure hospitalization (27.7% vs 56.1%; P = 0.016).

CONCLUSIONS

A 4-leaflet configuration of the tricuspid valve is observed in approximately one-third of patients undergoing transcatheter edge-to-edge tricuspid repair, which is associated with an increased risk of residual TR after the procedure.

[Current technologies in interventional treatment of tricuspid valve regurgitation]

For a long time, severe tricuspid valve regurgitation (TR) was an underestimated disease, especially in the older population and was associated with high morbidity and mortality. Due to the high perioperative mortality of tricuspid valve surgery, historically only pharmaceutical treatment was a practical treatment option. In the first studies interventional approaches could achieve promising results with an effective reduction of TR with simultaneous proof of a convincing safety profile. Conceptually, the currently available interventional treatment options can be divided into three concepts: coaptation systems (edge-to-edge repair), annuloplasty and interventional valve replacement. The largest clinical experience and best scientific body of evidence could so far be generated in the field of coaptation systems. Very promising preliminary results with effective reduction of TR and improvement of the clinical symptoms are, however, also available for interventional valve replacement. Meticulous preprocedural diagnostics with selection of the most suitable treatment option for each individual patient is paramount for successful treatment in this critically ill patient cohort. Future prospective randomized studies will investigate the net benefit of an interventional treatment of TR in comparison to a purely conservative treatment concept.