Treatment of Severe TRIcuspid Regurgitation in Patients with Advanced Heart Failure with CAval Vein Implantation of the Edwards Sapien XT VALve (TRICAVAL): a randomised controlled trial

New Approaches to Assessment and Management of Tricuspid Regurgitation Before Intervention

Severe tricuspid regurgitation (TR) is a progressive condition associated with substantial morbidity, poor quality of life, and increased mortality. Patients with TR commonly have coexisting conditions including congestive heart failure, pulmonary hypertension, chronic lung disease, atrial fibrillation, and cardiovascular implantable electronic devices, which can increase the complexity of medical and surgical TR management. As such, the optimal timing of referral for isolated tricuspid valve (TV) intervention is undefined, and TV surgery has been associated with elevated risk of morbidity and mortality. More recently, an unprecedented growth in TR treatment options, namely the development of a wide range of transcatheter TV interventions (TTVI) is stimulating increased interest and referral for TV intervention across the entire medical community. However, there are no stepwise algorithms for the optimal management of symptomatic severe TR before TTVI. This article reviews the contemporary assessment and management of TR with addition of a medical framework to optimize TR before referral for TTVI.

Transcatheter tricuspid valve interventions: Current devices and clinical evidence

The tricuspid valve is known as "the forgotten valve". Tricuspid regurgitation (TR) is a highly prevalent valvular heart disease. TR is often late in the course of the disease when it becomes symptomatic, often being a marker of late-stage chronic heart failure with a poor prognosis and high mortality rate at long-term follow-up. Despite the clear correlation between TR and mortality, most TR patients are under-treated. Neither pharmacologic nor surgical treatment demonstrates a significant survival benefit. Isolated tricuspid valve surgery has the highest mortality rate of all valve surgeries. Therefore, there is an urgent clinical need for minimally invasive therapies to meet the needs of patients with TR. In recent years, a variety of transcatheter tricuspid valve interventions representing less invasive alternatives to surgery have shown promising results, which bring hope to patients with severe TR. The purpose of this review is to provide a complete and updated overview on current transcatheter tricuspid valve interventions and clinical evidence.

A comprehensive overview of surgical and transcatheter therapies to treat tricuspid regurgitation in patients with heart failure

PURPOSE OF REVIEW

The unique pathophysiologic considerations of severe tricuspid regurgitation (TR) have led to advancements in surgical and transcatheter treatments. The purpose of this review is to highlight the current surgical and transcatheter tricuspid valve interventions (TTVI) to functional TR.

RECENT FINDINGS

Surgical repair with ring annuloplasty consistently demonstrates better outcomes than surgical replacement or other repair approaches. However, surgical uptake of TR correction remains relatively low, and operative mortality rates are still high owing to multiple comorbidities and advanced tricuspid valve disease/right ventricular dysfunction at time of referral. Pivotal trials for tricuspid transcatheter edge-to-edge repair (T-TEER) and transcatheter TV replacement (TTVR) indicate improved quality of life compared to medical therapy alone for high-surgical-risk patients with severe symptomatic TR. Trials are underway to assess caval valve implantation (CAVI), which holds hope for many severe TR patients who are not ideal candidates for T-TEER or orthotopic TTVR. Peri-procedural optimization of right ventricular function remains critical to promote both device success and patient outcomes.

SUMMARY

Clinical outcomes after surgical TV intervention are poor, often due to intervening late in the disease course of TR. TTVI covers a treatment gap for patients deemed inoperable or high-surgical-risk, but earlier referral for TV interventions is still important prior to patients developing multiorgan dysfunction from chronic untreated TR.

Immune response following transcatheter aortic valve procedure

Aortic valve stenosis is the most common type of heart valve disease in the United States and Europe and calcific aortic stenosis (AS) affects 2-7% of people aged 65 years and older. Aortic valve replacement (AVR) is the only effective treatment for individuals with this condition. Transcatheter Aortic Valve Replacement (TAVR) has been widely accepted as a minimally invasive therapeutic approach for addressing symptomatic AS in patients who are considered to have a high risk for traditional surgical intervention. TAVR procedure may have a paradoxical effect on the immune system and inflammatory status. A major portion of these immune responses is regulated by activating or inhibiting inflammatory monocytes and the complement system with subsequent changes in inflammatory cytokines. TAVR has the potential to induce various concurrent exposures, including disruption of the native valve, hemodynamic changes, antigenicity of the bioprosthesis, and vascular damage, which finally lead to the development of inflammation. On the other hand, it is important to acknowledge that TAVR may also have anti-inflammatory effects by helping in the resolution of stenosis.The inflammation and immune response following TAVR are complex processes that significantly impact procedural outcomes and patient well-being. Understanding the underlying mechanisms, identifying biomarkers of inflammation, and exploring therapeutic interventions to modulate these responses are crucial for optimizing TAVR outcomes. Further research is warranted to elucidate the precise immunological dynamics and develop tailored strategies to attenuate inflammation and enhance post-TAVR healing while minimizing complications.

Pharmacological Considerations during Percutaneous Treatment of Heart Failure

Heart Failure (HF) remains a global health challenge, marked by its widespread prevalence and substantial resource utilization. Although the prognosis has improved in recent decades due to the treatments implemented, it continues to generate high morbidity and mortality in the medium to long term. Interventional cardiology has emerged as a crucial player in HF management, offering a diverse array of percutaneous treatments for both acute and chronic HF. This article aimed to provide a comprehensive review of the role of percutaneous interventions in HF patients, with a primary focus on key features, clinical effectiveness, and safety outcomes. Despite the growing utilization of these interventions, there remain critical gaps in the existing body of evidence. Consequently, the need for high-quality randomized clinical trials and extensive international registries is emphasized to shed light on the specific patient populations and clinical scenarios that stand to benefit most from these innovative devices.

Lead management in patients undergoing percutaneous tricuspid valve replacement or repair: a 'heart team' approach

Clinically significant tricuspid regurgitation (TR) has historically been managed with either medical therapy or surgical interventions. More recently, percutaneous trans-catheter tricuspid valve (TV) replacement and tricuspid trans-catheter edge-to-edge repair have emerged as alternative treatment modalities. Patients with cardiac implantable electronic devices (CIEDs) have an increased incidence of TR. Severe TR in this population can occur for multiple reasons but most often results from the interactions between the CIED lead and the TV apparatus. Management decisions in patients with CIED leads and clinically significant TR, who are undergoing evaluation for a percutaneous TV intervention, need careful consideration as a trans-venous lead extraction (TLE) may both worsen and improve TR severity. Furthermore, given the potential risks of 'jailing' a CIED lead at the time of a percutaneous TV intervention (lead fracture and risk of subsequent infections), consideration should be given to performing a TLE prior to a percutaneous TV intervention. The purpose of this 'state-of-the-art' review is to provide an overview of the causes of TR in patients with CIEDs, discuss the available therapeutic options for patients with TR and CIED leads, and advocate for including a lead management specialist as a member of the 'heart team' when making treatment decisions in patients TR and CIED leads.

Characterization of Screen Failures Among Patients Evaluated for Transcatheter Tricuspid Valve Repair (TriSelect-Study)

BACKGROUND

Transcatheter tricuspid valve repair (TTVr) has significantly expanded treatment options for tricuspid regurgitation (TR). However, a sizeable proportion of patients are still declined for TTVr and little is known about their clinical characteristics and cardiac morphology.

OBJECTIVES

This study sought to characterize patients who screen fail for TTVr with respect to their clinical characteristics and cardiac morphology.

METHODS

A total of 547 patients were evaluated for TTVr between January 2016 to December 2021 from 3 centers in the United States and Germany. Clinical records and echocardiographic studies were used to assess medical history and right ventricular (RV) and tricuspid valve (TV) characteristics.

RESULTS

Median age was 80 (IQR: 74-83) years and 60.0% were female. Over half (58.1%) were accepted for TTVr. Of those who were deemed unsuitable for TTVr (41.9%), the most common exclusion reasons were anatomical criteria (56.8%). In the regression analysis, RV and right atrial size, TV coaptation gap, and tethering area were identified as independent screen failure predictors. Other rejection reasons included clinical futility (17.9%), low symptom burden (12.7%), and technical limitations (12.7%). Most of the excluded patients (71.6%) were managed conservatively with medical therapy, while a small number either proceeded to TV surgery (22.3%) or subsequently became eligible for transcatheter tricuspid valve replacement in later available clinical trials in the United States (6.1%).

CONCLUSIONS

The majority of TTVr screen failure patients are excluded due to TV, right atrial, and RV enlargement. However, a significant proportion is excluded due to clinical futility. These identifiable anatomical and clinical characteristics emphasize the importance of earlier referral and intervention of TR and the need for continued innovation of Transcatheter tricuspid valve interventions.

Transcatheter Tricuspid Valve Interventions: A Triumph for Transcatheter Procedures?

Tricuspid regurgitation (TR) is a common valvular pathology, estimated to affect 1.6 million people in the United States alone. Even though guidelines recommend either medical therapy or surgical treatment for TR, the misconception of TR as a benign disease along with the high mortality rates of surgical intervention led to undertreating this disease and commonly describing it as a "forgotten" valve. Recently, the development of transcatheter interventions for TR show promising potential for use in the clinical setting. There are currently few approved and numerous tested percutaneously delivered devices, which can be categorized, based on their mechanism of action, to either valve repair or valve replacement procedures. Both procedures were tested in clinical trials and show an echocardiographic reduction in TR sustained for at least 1 year after the procedure, as well as symptom relief and functional improvement of the patients. Device selection should be personalized, taking into consideration the anatomy of each valve and the available options at each heart center. Moreover, appropriate patient selection and timing of the procedure are also crucial for the success of the procedure. In this review, we analyze the clinical trials available for all devices currently approved or tested, aiming to provide a comprehensive summary of the most recent evidence in the field of transcatheter TR interventions.

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.

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.

Transcatheter interventions for severe tricuspid regurgitation: a literature review

The prevalence of tricuspid regurgitation (TR) increases with age, affecting 65%-85% of adults. Primary TR is caused by a congenital or acquired abnormality of the tricuspid valve apparatus (leaflets, chordae, papillary muscles, or annulus). Secondary TR is due to insufficient coaptation from dilation of tricuspid valve annulus due to the right ventricle (RV) or right atrium (RA) remodeling and increased RV pressures. Isolated TR is without increased RV pressures and is associated with atrial fibrillation. Mild TR is a benign disease. Moderate to severe tricuspid regurgitation has independently been associated with increased mortality. Most of these patients are treated medically due to poor outcomes with surgical repair of isolated TR. The in-hospital mortality rate is 8.8%, and the median length of stay in hospital is 11 days resulting in higher healthcare costs. Even if the patients undergo surgical repair or replacement, available data do not show improvement in survival. With a more detailed understanding of the complex anatomy and physiology of the tricuspid valve and significant complications from untreated tricuspid valve disease, the approach to the management of TR has shifted from a conservative approach to a process of prevention and intervention. In the past decade, transcatheter tricuspid valve interventions and tricuspid annuloplasty rings have been developed, contributing to decreased mortality from surgical repair. Transcatheter tricuspid valve intervention techniques have improved survival, quality of life, and reduced heart failure rehospitalization. This review summarizes normal anatomy, types of TR, etiology and different mechanisms of TR, echocardiographic assessment of the severe TR, and highlights various percutaneous transcatheter techniques for tricuspid valve repair.

Clinical and Echocardiographic Outcomes of Transcatheter Tricuspid Valve Interventions: A Systematic Review and Meta-Analysis

Background

Medically managed tricuspid regurgitation (TR) has detrimental outcomes. Transcatheter tricuspid valve interventions (TTVIs) represent an alternative to surgery in high-risk patients; however, only early experiences exist.

Aim

The aim of this study was to analyze the clinical and echocardiographic outcomes of TTVI.

Methods

MEDLINE, ISI Web of Science, and SCOPUS databases were searched for studies published up to June 2021. Studies reporting data on outcome post-TTVIs were included. This study was designed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) requirements. The primary endpoint was all-cause mortality at 30-day and 1-year post-TTVI.

Results

Out of 2,718 studies, 27 were included. Notably, 30-day and 1-year all-cause mortalities were 5% (95% confidence interval [CI]: 4–8%, p < 0.001) and 25% (95% CI: 12–45%, p = 0.016). Procedural success was associated with a 58% risk reduction in 1-year mortality vs. lack thereof (odds ratio 0.42, 95% CI: 0.27–0.66, p < 0.001). TTVI is associated with a significant reduction in TR severity (TR EROA, mean difference [MD] 0.31 cm²; 95% CI: 0.23–0.39 cm², p < 0.001; regurgitant volume, MD 23.54 ml; 95% CI: 17.4–29.68 ml, p = 0.03) and increase in forward stroke volume (FSV, MD 3.98 ml; 95% CI: 0.11–7.86 ml, p = 0.04).

Conclusion

TTVI significantly reduces TR severity and increases FSV and is associated with improved survival at 1 year compared with patients without procedural success. Long-term outcomes compared with medical therapy await the results of ongoing pivotal trials; nonetheless, TTVIs appear to be a promising alternative to surgery for TR.

Tricuspid Valve Percutaneous Therapies

PURPOSE OF REVIEW

In this review, we have focused on the currently available transcatheter tricuspid valve therapies, device selection, as well as role and management of tricuspid regurgitation (TR) in the setting of other transcatheter valvular procedures.

RECENT FINDINGS

In this review, we have enlisted the recently finished as well as ongoing trials in the percutaneous tricuspid valve therapies. TR is highly prevalent yet remains underrecognized and is often untreated. TR has traditionally been managed conservatively with medical therapies including diuretics for volume management, whereas surgical therapies are reserved for those undergoing left-sided valvular surgery. Although the transcatheter devices for tricuspid repair and replacement are in clinical trials, the experience to date for their effectiveness and safety has been reassuring.

Current Status of Transcatheter Tricuspid Valve Therapies

Tricuspid regurgitation is a complex disease that carries a poor prognosis, and surgical repair is associated with high mortality. In light of the success of other transcatheter-based valve interventions, transcatheter tricuspid therapy has recently seen exponential use both clinically and in innovation. Given the rapid development of many tricuspid systems and multiple on-going clinical trials, the aim of this review is to highlight the current state of transcatheter tricuspid therapeutics and to provide an up-to-date view of their clinical use, outcomes and future directions.

Six-Month Outcomes of the TricValve® System in Patients with Tricuspid Regurgitation: TRICUS EURO Study

BACKGROUND

Severe tricuspid regurgitation (TR) is frequently associated with significant morbidity and mortality; such patients often deemed to be at high surgical risk. Heterotopic bi-caval stenting is an emerging, attractive transcatheter solution for these patients.

OBJECTIVES

To evaluate the 30-day safety and 6-month efficacy outcomes of specifically designed bioprosthetic valves for the superior and inferior vena cava.

METHODS

TRICUS EURO is a non-blinded, non-randomized, single-arm, multicenter, prospective trial that enrolled patients from 12 European centers between December 2019 to February 2021. High risk individuals with severe symptomatic TR despite optimal medical therapy were included. Primary end point was quality of life (QOL) improvement measured by Kansas City Cardiomyopathy Questionnaire (KCCQ12) and New York Heart Association functional class (NYHA) improvement at 6-month follow-up.

RESULTS

35 patients (mean age 76±6.8 years; 83% women) were treated with TricValve® system. All patients at baseline were at NYHA ≥ 3 status. At 30-days, procedural success was 94% with no procedural deaths or conversions to surgery. A significant increase in QOL at 6-months follow-up was observed (baseline and 6-month KCCQ: 42.01±22.3 vs. 59.7±23.6 respectively; p=0.004), correlating with a significant improvement in NYHA functional class with 79.4% of patients noted to be in class I or II at 6 months (p=0.0006). The 6-month all-cause mortality and heart failure hospitalization rates were 8.5% and 20%, respectively.

CONCLUSIONS

The dedicated bi-caval system for treating severe, symptomatic TR was associated with high procedural success rate and significant increase in both, QOL and functional improvements at 6-months follow-up.

Restructuring the Heart From Failure to Success: Role of Structural Interventions in the Realm of Heart Failure

Heart failure through the spectrum of reduced (HFrEF), mid-range (or mildly reduced or HFmEF), and preserved ejection fraction (HFpEF), continues to plague patients' quality of life through recurrent admissions and high mortality rates. Despite tremendous innovation in medical therapy, patients continue to experience refractory congestive symptoms due to adverse left ventricular remodeling, significant functional mitral regurgitation (FMR), and right-sided failure symptoms due to significant functional tricuspid regurgitation (FTR). As most of these patients are surgically challenging for open cardiac surgery, the past decade has seen the development and evolution of different percutaneous structural interventions targeted at improving FMR and FTR. There is renewed interest in the sphere of left ventricular restorative devices to effect reverse remodeling and thereby improve effective stroke volume and patient outcomes. For patients suffering from HFpEF, there is still a paucity of disease-modifying effective medical therapies, and these patients continue to have recurrent heart failure exacerbations due to impaired left ventricular relaxation and high filling pressures. Structural therapies involving the implantation of inter-atrial shunt devices to decrease left atrial pressure and the development of implantable devices in the pulmonary artery for real-time hemodynamic monitoring would help redefine treatment and outcomes for patients with HFpEF. Lastly, there is pre-clinical data supportive of soft robotic cardiac sleeves that serve to improve cardiac function, can assist contraction as well as relaxation of the heart, and have the potential to be customized for each patient. In this review, we focus on the role of structural interventions in heart failure as it stands in current clinical practice, evaluate the evidence amassed so far, and review promising structural therapies that may transform the future of heart failure management.

Early Clinical Experience With the TRICENTO Bicaval Valved Stent for Treatment of Symptomatic Severe Tricuspid Regurgitation: A Multicenter Registry

BACKGROUND

Patients with severe tricuspid regurgitation present late and are often ineligible for surgery or transcatheter repair systems. Transfemoral venous implantation of a bicaval valved stent has been proposed as therapeutic option in selected patients. The aim of this study was to summarize the early procedural and clinical outcomes of the novel TRICENTO system for the treatment of patients with symptomatic severe tricuspid regurgitation.

METHODS

All consecutive patients treated with the custom-made TRICENTO implant at the participating centers were included in this retrospective multicentre registry.

RESULTS

A total of 21 high-risk patients (mean age 76±7 years; 67% female) with severe or higher grade tricuspid regurgitation were analyzed. The majority of the patients were in New York Heart Association class III/IV (95%), had peripheral edema (95%), and previous hospitalization for right heart failure (67%). Technical success was 100%, and there was no case of in-hospital mortality. During follow-up (median 61 days), symptomatic improvement was observed (65% in New York Heart Association class I/II; P<0.001). Computed tomography revealed asymptomatic fractures of the TRICENTO prosthesis in 3 patients. Cardiac magnetic resonance imaging obtained in 7 patients showed a significant decrease (252±65 mm³ at baseline versus 216±58 mm³ at follow-up, P=0.006) of right ventricular end-diastolic volume. The overall-survival rate was 76% at 1 year.

CONCLUSIONS

The present data indicate the feasibility of transfemoral bicaval valved stent implantation for the treatment of severe tricuspid regurgitation. Functional improvement and signs of right ventricular reverse remodeling were observed. Stent fractures did not impair valve function, but require refinement of prosthesis design and careful assessment of eligibility criteria.

Caval Valve Implantation

Transcathetertherapy has expanded the treatment options for patients with heart valve disease. Interventional therapy for aortic, mitral, and pulmonic valve disease is well established; however, catheter-based approaches to tricuspid regurgitation (TR) are still in early stages of development. For some of the interventional concepts to TR, including the edge-to-edge-repair, transcatheter annuloplasty, the tricuspid spacer, and caval valves, procedural feasibility and favorable early clinical outcome have been demonstrated in small compassionate case series. This article reviews the pathophysiological background and current evidence for caval valve implantation and examines the potential role of this approach for the treatment of severe TR.

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.

Transcatheter tricuspid valve interventions: Current devices and associated evidence

Tricuspid regurgitation (TR) is a common finding in patients with chronic cardiopathy, and often a marker of an advanced disease. Being silent or with symptoms intertwined with the primitive left heart disease, TR has often been neglected, leading to the late referral of patients with advanced right-heart failure. Hence, isolated tricuspid surgery has been associated with high morbidity and mortality rates, the worse of all valve interventions, and medical management has been limited to symptomatic treatment. In this context, percutaneous therapies for severe TR have gained traction, addressing the unmet therapeutic gap for a less invasive disease-modifying management. The aim of this review is to provide an updated overview on transcatheter tricuspid valve interventions, focusing on devices' characteristics, associated evidence, and future perspectives.

Renal and hepatic function of patients with severe tricuspid regurgitation undergoing inferior caval valve implantation

Due to progressive abdominal-venous congestion severe tricuspid regurgitation (TR) is a common cause of cardiorenal and cardiohepatic syndrome. We initiated the TRICAVAL study to compare interventional valve implantation into the inferior vena cava (CAVI) versus optimal medical therapy (OMT) in severe TR. In the present subanalysis, we aimed to evaluate the effects of CAVI on clinical signs of congestion, renal and hepatic function. TRICAVAL was an investigator-initiated, randomized trial. Twenty-eight patients with severe TR were randomized to OMT or CAVI using an Edwards Sapien XT valve. Probands who completed the 3-month follow-up (CAVI [n = 8], OMT [n = 10]) were evaluated by medical history, clinical examination, and laboratory testing at baseline, 3 and 12 months. After 3 months, the CAVI group exhibited a significant reduction of body weight (from 80.7 [69.0–87.7] kg to 75.5 [63.8–84.6] kg, p < 0.05) and abdominal circumference (from 101.5 ± 13.8 cm to 96.3 ± 15.4 cm, p ≤ 0.01) and a trend to lower doses of diuretics compared to OMT. Renal and hepatic function parameters did not change significantly. Within a short-term follow-up, CAVI led to an improvement of clinical signs of venous congestion and a non-significant reduction of diuretic doses compared to OMT.

Caval Valve Implantation (CAVI): An Emerging Therapy for Treating Severe Tricuspid Regurgitation

Severe tricuspid regurgitation remains a challenging heart-valve disease to effectively treat with high morbidity and mortality at mid-term. Currently guideline-directed medical treatment is limited to escalating dose of diuretics, and the rationale and timing of open-heart surgery remains controversial. Emerging percutaneous therapies for severe tricuspid regurgitation continue to show promising results in early feasibility studies. However, randomized trial data is lacking. Additionally, many patients are deemed unsuitable for these emerging therapies due to anatomical or imaging constraints. Given the technical simplicity of the bicaval valve implantation (CAVI) technique compared to other transcatheter devices, CAVI is postulated as a suitable alternative for a wide variety of patients affected with severe+ tricuspid regurgitation. In this review we illustrate the current evidence and ongoing uncertainties of CAVI, focusing on the novel CAVI-specific devices.

Imaging for transcatheter native tricuspid valve intervention: patient selection, procedural planning and interventional guidance

There are an increasing number of transcatheter tricuspid valve interventions being performed worldwide using commercially available and investigational devices. Imaging in the pre-procedural and periprocedural period is essential for procedural and clinical success. Echocardiographic-based techniques are particularly important in these procedures, especially for interventional guidance. This review summarizes the current devices in use and how imaging is used for patient selection, procedural planning, and interventional guidance. The most commonly used method of transcatheter tricuspid intervention is edge-to-edge repair using the MitraClip or TriClip devices (Abbott, Santa Clara, CA, USA). Randomized controlled data is pending but observational studies have demonstrated success, especially in the setting of smaller coaptation gaps and adequate transesophageal imaging windows. Direct annuloplasty with the Cardioband (Edwards Lifesciences, Irvine, CA, USA) has also been used in many centers and has demonstrated success when the anatomy and mechanism of tricuspid regurgitation are appropriate for annuloplasty based on imaging evaluation. Lastly, transcatheter valve replacement is becoming more common using several investigational devices and relies heavily on imaging methods to achieve procedural success.

Transcatheter treatment of severe tricuspid regurgitation

PURPOSE OF REVIEW

Severe tricuspid regurgitation is a commonly prevalent valvular heart disease that is an independent adverse prognostic marker. However, the majority of patients with tricuspid regurgitation are managed medically; isolated tricuspid valve surgery is rarely performed, partly owing to high associated in-hospital mortality. Therefore, several transcatheter tricuspid valve interventions (TTVIs) that have been developed over the last few years to address this unmet clinical need.

RECENT FINDINGS

The early experience with TTVI has shown that most devices can be safely implanted with excellent rates of technical success and acceptable safety outcomes. Most TTVI recipients have significant improvement in tricuspid regurgitation severity, functional class, and quality of life. Recent retrospective data also suggest mortality benefit of TTVI compared with medical management. There are several issues that need to be addressed prior to widespread adoption of TTVI, including more effective tricuspid regurgitation reduction and need for longer term efficacy data.

SUMMARY

TTVI has emerged as an attractive treatment option for management of high-risk patients with tricuspid regurgitation. In this review, we will discuss the anatomical considerations specific to tricuspid valve, patient selection, preprocedure planning, and summarize the current evidence and future perspectives on TTVI.

[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.

Transcatheter Tricuspid Valve Intervention: Current Perspective

Tricuspid regurgitation (TR) adversely impacts both quality of life and long-term survival, which generates interest in therapeutic approaches to mitigate these effects. Historically, therapeutic options for TR were limited to surgical approaches, which are often complicated by significant morbidity and mortality in elderly patients with multiple comorbidities. This gap in therapeutic options led to the rapid evolution of transcatheter tricuspid valve intervention (TTVI), with a wide variety of approaches pursued and early results suggesting that TTVI improves clinical outcomes. Numerous strategies, including edge-to-edge repair, annular reduction, spacers, caval valve implantation, and transcatheter tricuspid valve replacement form the basis of TTVI today. In this review, the authors discuss the current state of each approach.

Update on Transcatheter Tricuspid Valve Replacement Therapies

Severe tricuspid regurgitation is relatively common, especially in the elderly, and portends poor survival. Neither medical therapy nor conventional surgery is efficacious for most patients. In contrast, transcatheter tricuspid valve interventions are showing promise to improve quality of life and mortality. Although there is more clinical experience with transcatheter tricuspid valve repair, there are many patients for which repair is either not possible or cannot optimally reduce the severity of tricuspid regurgitation. Transcatheter tricuspid valve replacement is rapidly emerging and may ultimately become the preferred treatment option. In this review, we discuss transcatheter tricuspid valve replacement, analyze the devices in development and in clinical trials, and highlight the advantages and drawbacks of transcatheter tricuspid valve replacement vs. repair.

Transcatheter Interventions for Tricuspid Valve Disease: What to Do and Who to Do It On

Tricuspid valve disease, and particularly the management of severe tricuspid regurgitation (TR), has gained momentum in recent years. Although it is well known that this frequent condition is associated with poor clinical outcomes, these patients have been classically managed medically, leading to end-stage right ventricular heart failure. Moreover, late referral to surgery has contributed to a high rate of periprocedural complications and in-hospital surgical mortality. Thus, the development of a less invasive catheter-based therapy would be of high clinical relevance in this context. Several transcatheter tricuspid valve intervention (TTVI) devices have been developed in recent years. The particular characteristics of the tricuspid valve (large noncalcific annulus, presence of chief surrounding structures such as the conduction system or the right coronary artery) make multimodality imaging (eg, transesophageal echocardiography, computed tomography) key in the preprocedural assessment of TTVI. According to their mechanism of action and therapeutic target, TTVI includes transcatheter repair either with coaptation or annuloplasty systems, caval valve devices, and transcatheter tricuspid valve replacement. The initial TTVI experience showed that most procedures were well tolerated, with high procedural success and low in-hospital and early mortality. Also, most TTVI recipients improved their functional status and recent data suggest improved outcomes compared with medical management. However, the rate of significant residual TR after transcatheter tricuspid valve repair remains high and very scarce data exist on longer term (beyond 6-12 months) outcomes. The present review provides an overview regarding the framework of chronic TR and TTVI therapeutic options, and describes the updated current evidence in this challenging field.

Treatment of isolated tricuspid regurgitation in 2020: an update

Tricuspid valve regurgitation is an insidious pathology that is associated with increased mortality if left untreated. Conversely, surgical correction of tricuspid regurgitation is burdened by poor outcomes, especially when right ventricular dysfunction, kidney disease, or liver disease occur. There is, therefore, increasing interest in transcatheter approaches as an alternative to surgery in patients at high or prohibitive surgical risk. The development of percutaneous devices to treat tricuspid regurgitation has several technical challenges, mainly because of the complexity of valve anatomy, thus requiring accurate patient selection. Here we review the currently available transcatheter approaches to treat severe tricuspid regurgitation.

Catheter-based treatment of tricuspid regurgitation: state of the art

Tricuspid regurgitation is a highly prevalent condition, with detrimental effects on long-term survival. However, it has been historically neglected, and only surgically addressed when symptomatic diuretic agents proved insufficient to alleviate congestion. Besides, mortality rates of isolated tricuspid regurgitation surgery have been persistently high, even in contemporary series. This has led to the advent of a myriad of transcatheter tricuspid valve interventions mimicking current surgical technologies, for which a comprehensive imaging work-up holds the key for proper patient selection and intraprocedural monitoring. Although initially designed for compassionate use patients, growing experience and encouraging results of these less-invasive technologies are broadening the spectrum of beneficiaries. In this review, we will focus on the current picture of transcatheter tricuspid valve interventions, with special interest on the current understanding of pathoanatomic tricuspid regurgitation progression, preprocedural multimodality imaging and the latest experience on the different transcatheter devices.

Impact of inferior caval valve implantation on severity of tricuspid regurgitation and right heart function

AIMS

Severe tricuspid regurgitation (TR) is a common finding in heart failure patients and associated with increased mortality. New interventional therapeutic options are needed as many heart failure patients are unfit for surgery. The TRICAVAL study compared valve implantation into the inferior vena cava (CAVI) with optimal medical therapy (OMT) in patients with severe TR. Here, we report details on the impact of CAVI on TR severity as well as right heart function and morphology.

METHODS AND RESULTS

We randomized 28 patients with severe TR to CAVI (n = 14) with transfemoral implantation of an Edwards Sapien XT valve into the inferior vena cava or OMT (n = 14). Inclusion and exclusion criteria were based on anatomical and clinical parameters. Echocardiographic measurements were performed at baseline, at the first postoperative day and one, three, and twelve months after randomization. As proof of concept of an effective sealing of the inferior vena cava, we detected a significant decrease in systolic hepatic vein reflux volume (11.0 [6.2-21.9] mL vs 3.5 [0.6-8.5] mL, P = .016) and hepatic vein diameter (11.5 [10.0-14.8] mm vs 10.0 [9.3-11.8] mm, P = .034) at thirty-day follow-up. However, CAVI had no significant impact on TR, cardiac function, and morphology.

CONCLUSIONS

Caval valve implantation significantly reduced systolic reflux into the hepatic veins but was not associated with an improvement in cardiac function, morphology, or TR severity.

Transcatheter therapies for severe tricuspid regurgitation. Quo vadis?

Moderate-to-severe tricuspid regurgitation (TR) is common and is associated with a poor prognosis. To date, most patients are undertreated; therefore, transcatheter options could be clinically impactful in those who are denied surgery. Several transcatheter solutions have been developed that address the problem via leaflet enhancement, annuloplasty, or heterotopic implantation of self-expandable or balloon-expandable valves in the caval veins. A comprehensive patient evaluation, based on multimodality imaging techniques for a better understanding of the valvular pathology and TR mechanism, remains paramount for an appropriate device selection. To date, several trials have shown the feasibility and safety of a multitude of devices in this setting, but data from randomized clinical trials regarding clinical benefit based on hard endpoints are still lacking. Although the optimal patient profile and timing of intervention remain under investigation, data from available studies indicate that an earlier treatment referral, before onset of irreversible right ventricular remodeling, could be beneficial. This review discusses the present landscape and future implications of transcatheter therapies for severe TR.