Transcatheter Tricuspid Valve Therapy: From Anatomy to Intervention

Transcatheter tricuspid valve replacement with LuX-valve device: Overview of key echocardiographic considerations

Tricuspid regurgitation is a common valve disease with high incidence and poor prognosis. For elderly patients and those with a history of open heart surgery, second thoracotomy and valve replacement carry a high risk. Transcatheter tricuspid valve replacement (TTVR) has become an alternative treatment for patients with high surgical risk. LuX-Valve is a novel self-expandable valve that does not rely on radial force to anchor the valve annulus. The preliminary results have been satisfactory, and this technology is gradually being adopted in China and around the world. Successful implementation of this technique depends on echocardiographic preoperative screening, intraoperative guidance, and postoperative follow-up. The purpose of this article is to provide a state-of-the-art review of the key points and technical considerations for preoperative screening, intraoperative guidance, and postoperative follow-up for TTVR.

Cardiac Surgery and Transcatheter Intervention for Valvular Heart Disease in Carcinoid Syndrome: Risk Factors, Outcomes, and Evolving Therapeutic Strategies

Carcinoid heart disease (CHD) affects right-sided valves and causes significant mortality and morbidity. Even though the pathophysiology of the disease is not entirely understood, it is known that chronic exposure to high levels of circulating serotonin is the main factor responsible for developing valvular heart disease. Cardiac imaging plays a critical role in the management of CHD, so the final diagnosis can be performed through multimodal imaging techniques and the measurement of biomarkers. Moreover, in observational studies, surgical treatment of carcinoid-induced valve disease has been found to improve outcomes. Despite advancements in pre-operative preparation in recent years, mortality rates remain high in elderly patients and those with multiple comorbidities due to the risk of intra-operative carcinoid crisis and high post-operative bleeding. In this comprehensive review, we will analyze the causes of carcinoid syndrome and how it can result in severe right heart failure. The role of different imaging modalities in detecting heart valve disease will be discussed together with the therapeutic options at our disposal, such as medical treatment, surgery, and the novel role of transcatheter intervention.

Key Imaging Factors for Transcatheter Management of Tricuspid Regurgitation: Device and Patient Selection

The growing awareness of tricuspid regurgitation (TR) and the fast-expanding array of devices aiming to percutaneously repair or replace the tricuspid valve have underscored the central role of multi-modality imaging in comprehensively assessing the anatomical and functional characteristics of TR. Accurate phenotyping of TR, the right heart, and pulmonary vasculature via echocardiography, computed tomography, and, occasionally, cardiovascular magnetic resonance and right heart catheterization is deemed crucial in choosing the most suitable treatment strategy for each patient and achieving procedural success. In the first part of the present review, key imaging factors for patient selection will be discussed. In the ensuing sections, an overview of the most commonly used, commercially available systems for transcatheter repair/replacement will be presented, along with their respective selection criteria and information on intraprocedural imaging guidance; these are edge-to-edge repair, orthotopic and heterotopic replacement, and valve-in-valve procedures.

Sex-Specific Insights into Etiology, Diagnosis, Treatment, and Prognosis in Significant Tricuspid Regurgitation: A Narrative Review

In recent decades, a burgeoning interest in tricuspid regurgitation (TR) has been prompted by a heightened awareness of its prevalence and the advent of dedicated percutaneous treatment approaches. Despite considerable understanding of its intricate anatomy and response to varying pressure and loading conditions, the impact of biological sex remains a subject of investigation. While TR typically afflicts more women, significant differences in TR etiology and post-treatment outcomes have not been conclusively established. This narrative review seeks to consolidate the latest evidence concerning sex-related nuances in anatomy, pathophysiology, diagnosis, treatment, and prognosis of significant tricuspid regurgitation. Through synthesizing this information, we aim to provide a comprehensive understanding of how sex may influence the management and prognosis of this condition.

A Novel Swine Model for Inducing Functional Tricuspid Valve Regurgitation

Functional tricuspid regurgitation (FTR) is the most common TR, although experimental models to effectively study it are scarce; therefore, this study aimed to establish a robust experimental swine model. A swine FTR model was developed using radiofrequency ablation, atrial septostomy, and right atrial volume overload. The baseline and follow-up echocardiography was performed to evaluate the progression FTR and changes in the heart. Autopsy was employed to verify the anatomy of tricuspid valve. One-month post intervention, among the subjects, one (8.3%) exhibited severe FTR, eight (66.7%) exhibited moderate TR, and three (25%) exhibited mild FTR. Each pig developed an atrial septal defect (diameter, 1.5 ± 0.5 cm). The tricuspid annular diameter significantly increased with enlargement of right heart (P < 0.05). No significant difference was found on left heart size and mitral regurgitation. We successfully developed a novel swine FTR model, providing a reliable and effective platform for further research on FTR.

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.

The safety of transesophageal echocardiography to guide transcatheter tricuspid valve edge-to-edge repair

BACKGROUND

Transesophageal echocardiography (TEE) is primarily used to guide transcatheter structural heart interventions, such as tricuspid transcatheter edge-to-edge repair (TEER). Although TEE has a good safety profile, it is still an invasive imaging technique that may be associated with complications, especially when performed during long transcatheter procedures or on frail patients. The aim of this study was to assess TEE-related complications during tricuspid TEER.

METHODS

This is a prospective study enrolling 53 patients who underwent tricuspid TEER for severe tricuspid regurgitation (TR). TEE-related complications were assessed clinically and divided into major (life-threatening, major bleeding requiring transfusions or surgery, organ perforation, and persistent dysphagia) and minor (perioral hypesthesia, < 24 h dysphagia/odynophagia, minor intraoral bleeding and hematemesis not requiring transfusion) RESULTS: The median age of the patient population was 79 years; 43.4% had severe, 39.6% massive, and 17.6% torrential TR. 62.3% of patients suffered from upper gastrointestinal disorders. Acute procedural success (APS) was achieved in 88.7% in a median device time of 36 min. A negative association was shown between APS and lead-induced etiology (r = -.284, p = .040), baseline TR grade (r = -.410, p = .002), suboptimal TEE view (r = -.349, p = .012), device time (r = -.234, p = .043), and leaflet detachment (r = -.496, p < .0001). We did not observe any clinical manifest major or minor TEE-related complications during the hospitalization.

CONCLUSIONS

Our study reinforces the good safety profile and efficacy of TEE guidance during tricuspid TEER. Adequate preoperative management and intraprocedural precautions are mandatory in order to avoid serious complications. Furthermore, suboptimal intraprocedural TEE views are associated with lower TR reduction rates.

HIGHLIGHTS

Transesophageal echocardiography is a crucial and safe technique for guiding transcatheter structural heart interventions. A mix of mid/deep esophageal and trans gastric views, as well as real-time 3D imaging is generally used to guide the procedure. Adequate preoperative management and intraprocedural precautions are mandatory in order to avoid serious problems. A shorter device time is associated with more rarely probe-related complications. Suboptimal intraprocedural TEE views are associated with lower TR reduction rates.

Perioperative Right Ventricular Dysfunction and Abnormalities of the Tricuspid Valve Apparatus in Patients Undergoing Cardiac Surgery

Right ventricular (RV) dysfunction frequently occurs after cardiac surgery and is linked to adverse postoperative outcomes, including mortality, reintubation, stroke, and prolonged ICU stays. While various criteria using echocardiography and hemodynamic parameters have been proposed, a consensus remains elusive. Distinctive RV anatomical features include its thin wall, which presents a triangular shape in a lateral view and a crescent shape in a cross-sectional view. Principal causes of RV dysfunction after cardiac surgery encompass ischemic reperfusion injury, prolonged ischemic time, choice of cardioplegia and its administration, cardiopulmonary bypass weaning characteristics, and preoperative risk factors. Post-left ventricular assist device (LVAD) implantation RV dysfunction is common but often transient, with a favorable prognosis upon resolution. There is an ongoing debate regarding the benefits of concomitant surgical repair of the RV in the presence of regurgitation. According to the literature, the gold standard techniques for assessing RV function are cardiac magnetic resonance imaging and hemodynamic assessment using thermodilution. Echocardiography is widely favored for perioperative RV function evaluation due to its accessibility, reproducibility, non-invasiveness, and cost-effectiveness. Although other techniques exist for RV function assessment, they are less common in clinical practice. Clinical management strategies focus on early detection and include intravenous drugs (inotropes and vasodilators), inhalation drugs (pulmonary vasodilators), ventilator strategies, volume management, and mechanical support. Bridging research gaps in this field is crucial to improving clinical outcomes associated with RV dysfunction in the near future.

Advances in Imaging for Tricuspid Transcatheter Edge-to-Edge Repair: Lessons Learned and Future Perspectives

Severe tricuspid valve (TV) regurgitation (TR) has been associated with adverse long-term outcomes in several natural history studies, but isolated TV surgery presents high mortality and morbidity rates. Transcatheter tricuspid valve interventions (TTVI) therefore represent a promising field and may currently be considered in patients with severe secondary TR that have a prohibitive surgical risk. Tricuspid transcatheter edge-to-edge repair (T-TEER) represents one of the most frequently used TTVI options. Accurate imaging of the tricuspid valve (TV) apparatus is crucial for T-TEER preprocedural planning, in order to select the right candidates, and is also fundamental for intraprocedural guidance and post-procedural follow-up. Although transesophageal echocardiography represents the main imaging modality, we describe the utility and additional value of other imaging modalities such as cardiac CT and MRI, intracardiac echocardiography, fluoroscopy, and fusion imaging to assist T-TEER. Developments in the field of 3D printing, computational models, and artificial intelligence hold great promise in improving the assessment and management of patients with valvular heart disease.

Functional Mitral and Tricuspid Regurgitation across the Whole Spectrum of Left Ventricular Ejection Fraction: Recognizing the Elephant in the Room of Heart Failure

Functional mitral regurgitation (FMR) and tricuspid regurgitation (FTR) occur due to cardiac remodeling in the presence of structurally normal valve apparatus. Two main mechanisms are involved, distinguishing an atrial functional form (when annulus dilatation is predominant) and a ventricular form (when ventricular remodeling and dysfunction predominate). Both affect the prognosis of patients with heart failure (HF) across the entire spectrum of left ventricle ejection fraction (LVEF), including preserved (HFpEF), mildly reduced (HFmrEF), or reduced (HFrEF). Currently, data on the management of functional valve regurgitation in the various HF phenotypes are limited. This review summarizes the epidemiology, pathophysiology, and treatment of FMR and FTR within the different patterns of HF, as defined by LVEF.

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.

The butterfly effect: Restoring the tricuspid coaptation after clipping the antero-septal commissure

Edge-to-edge tricuspid transcatheter repair requires extensive echocardiographic planning before the procedure. Sometimes, anatomic features may anticipate a suboptimal result. For this reason, a tailored strategy is the key to the procedural success. We report a case of massive tricuspid regurgitation due to multiple complex mechanisms that was successfully treated by clipping the antero-septal commissure to restore functional coaptation of the valve leaflets at multiple sites.

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.

Hemodynamics of transcatheter tricuspid valve replacement with Lux-Valve

Objective

Transcatheter tricuspid valve intervention (TTVI) has emerged as an alternative treatment option for high-risk and inoperable patients with symptomatic tricuspid regurgitation (TR). However, scarce data in hemodynamic profiles were available on TTVI. In this paper, we attempt to report the hemodynamic profiles of LuX-Valve.

Methods

30 patients from July 2020 to July 2021 were enrolled in this study. The patient was diagnosed with severe symptomatic TR. The clinical, invasive hemodynamic, and echocardiographic data were collected.

Results

The surgical success rate was 100%. The cardiac index and stroke volume increased sharply from 2.42(2.27, 2.85) and 47.8(43.6, 62.0) to 3.04 ± 0.63 and 57.2 ± 14.7, respectively. With the elimination of TR and the increase of forward blood flow of the tricuspid valve, the extravascular lung water [798.0 (673.0, 1147.0) vs. 850.3 ± 376.1, P < 0.01] increased subsequently. The peak right atrium pressure decreased after Lux-Valve implantation (21.0 ± 6.4 vs. 19.4 ± 6.5, P < 0.05). On the contrary, the nadir right atrium pressure increased [10.0(8.0, 15.0) vs. 12.0(10.0, 17.0), P < 0.01]. Notably, the right atrium pressure difference dropped sharply from 9.0(5.0, 13.0) to 5.0(4.0, 8.0) after Lux-Valve implantation. There was no significant change in the pulmonary artery pressure. The right atrium volume decreased from 128(83, 188) to 91(67, 167) mL at 1 month and 107(66,157) mL at 6 months. With the remolding of the right heart chamber, the tricuspid annulus diameter shrank significantly from 42.5 ± 5.6 to 36.6 ± 6.3 mm at 1 month and 36.0 (33.0, 38.0) at 6 months.

Conclusion

Invasive right atrium pressure may act as a potential candidate for TR evaluation and procedural guidance. Elimination of TR by LuX-Valve implantation improves the cardiac output and right atrium pressure and has no significant effect on the pulmonary artery pressure even with the increment of forward blood flow, suggesting the hemodynamic superiority of transcatheter tricuspid valve replacement but needs further study.

Funktionelle Trikuspidalklappeninsuffizienz – Klinische und echokardiografische Parameter für die Auswahl von Patient und Verfahren

Die sekundäre Trikuspidalklappeninsuffizienz (TI) ist ein häufiger Klappenfehler und führt oft erst in fortgeschrittenen Stadien zu Symptomen. Die Prognose von betroffenen Patienten ist eingeschränkt und die perioperative Letalität bei konventioneller Chirurgie der isolierten TI hoch, sodass kathetergestützte Verfahren einen enormen technischen Fortschritt in den letzten Jahren gemacht haben. Zudem hat die anatomische und auch klinische Patientenauswahl an Bedeutung gewonnen, da sowohl in der klinischen Präsentation als auch in der individuellen Anatomie der Trikuspidalklappe eine große Variabilität herrscht. Klinisch ist bzw. sind insbesondere das Vorhandensein einer (präkapillären) pulmonalen Hypertonie oder fortgeschrittene Stadien des Rechtsherz-Remodelings mit einer reduzierten Prognose nach kathetergestützten Eingriffen assoziiert. Zudem sind relevante Komorbiditäten und funktionelle Fitness/Gebrechlichkeit zu evaluieren. Echokardiografisch ist die funktionelle TI durch eine Anulus- und/oder rechtsventrikuläre bzw. rechtsatriale Dilatation gekennzeichnet, welche zu Koaptationsdefekten der Trikuspidalklappensegel und einer Zügelung der Segel („Tethering“) führen können. Die Ausprägung dieser Parameter sowie die Anulusgröße, der Schweregrad der TI und das Vorhandensein von transvalvulären Sonden im Bezug zur Trikuspidalklappe sind die wichtigsten echokardiografischen Parameter, die in die Patientenauswahl einfließen müssen.

Edge-to-Edge Repair for Tricuspid Valve Regurgitation. Preliminary Echo-Data and Clinical Implications from the Tricuspid Regurgitation IMAging (TRIMA) Study

Background: The natural history of tricuspid valve regurgitation (TR) is characterized by poor prognosis and high in-hospital mortality when treated with isolated surgery. We report the preliminary echocardiographic and procedural results of a prospective cohort of symptomatic patients with high to prohibitive surgical risk and at least severe TR who underwent transcatheter edge-to-edge repair through the TriClipTM system. Methods: From June 2020 to March 2022, 27 consecutive patients were screened, and 13 underwent transcatheter TriClipTM repair. In-hospital, 30-day and six-month clinical and echocardiographic outcomes were collected. Results: Nine patients had severe, three massive and one baseline torrential TR. Sustained TR reduction of ≥1 grade was achieved in all patients, of which 90% reached a moderate TR or less. On transthoracic echocardiographic examination, there were significant reductions in vena contracta width (p < 0.001), effective regurgitant orifice area (p < 0.001) and regurgitant volume (p < 0.001) between baseline and hospital discharge. We also observed a significant reduction in tricuspid annulus diameter (p < 0.001), right ventricular basal diameter (p = 0.001) and right atrial area (p = 0.026). Conclusion: Treatment with the edge-to-edge TriClip device is safe and effective. The resulting echocardiographic improvements indicate tricuspid valve leaflet approximation does not just significantly reduce the grade of TR but also affects adjacent structures and improves right ventricular afterload adaptation.

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.