Transcatheter Tricuspid Valve Intervention: Coaptation Devices

Transcatheter tricuspid valve intervention (TTVI) has recently emerged as an alternative for the treatment of severe tricuspid regurgitation (TR). Multiple percutaneous devices have been developed in the last decade with promising early results. Among them, the coaptation devices are designed to reduce TR severity by valve leaflet plication or occupying the regurgitant orifice with a spacer. To date, the MitraClip/TriClip devices (Abbott, Santa Clara, CA, USA), the PASCAL system (Edwards Lifesciencies, Irvine, CA, USA), and the FORMA device (Edwards Lifesciencies, Irvine, CA, USA) have been used as coaptation devices for treating severe TR. The present document aimed to review the clinical evidence on coaptation devices in the field of TTVI, describing its design characteristics, main procedural steps, and early and mid-term outcomes.

The tricuspid valve in review: anatomy, pathophysiology and echocardiographic assessment with focus on functional tricuspid regurgitation

The tricuspid valve (TV) is a complex anatomical structure that incorporates a saddle-shaped annulus, asymmetric leaflets, the subvalvular apparatus and the right ventricle and its loading conditions. In this paper, an appreciation of the normal anatomy and physiology of the TV is reviewed before discussing functional tricuspid regurgitation (TR), a disease that has garnered renewed interest due to increased awareness of adverse outcomes and novel transcatheter therapeutic options. Two and three-dimensional echocardiographic imaging of the TV using transthoracic and transesophageal windows are subsequently discussed. The future of cardiovascular medicine will have more to offer the “forgotten” right-sided chambers and valves, and this review aims to refresh knowledge and enthusiasm around the forgotten but crucially important TV.

Tangled wire in a Dacron band during Cardioband transcatheter tricuspid annuloplasty-How to solve the problem

Transcatheter tricuspid valve intervention (TTVI) is an emerging treatment for patients with symptomatic severe tricuspid regurgitation (TR). Currently, the issues that arise during TTVI are unclear. Here, a 78-year-old woman with severe TR underwent transcatheter tricuspid valve annuloplasty using a Cardioband (Edwards Lifesciences, Irvine, CA). We attempted to cinch the Dacron band after anchoring; however, it was impossible to connect the distal tip of the size adjustment tool and the Dacron band because the cinching wire was tangled around the Dacron band. We resolved this issue without surgical intervention, and eventually cinched the annulus. Final echocardiography revealed dramatic TR reduction. To our knowledge, no study has reported a tangled wire in a Dacron band during Cardioband use. Clinicians should be aware of the risks accompanying this concern in case where it is impossible to connect the distal tip of the size adjustment tool and the Dacron band during cinching.

Impact of pulmonary thromboendarterectomy on tricuspid regurgitation in patients with chronic thromboembolic pulmonary hypertension: a single-center prospective cohort experience

Background

For patients with chronic thromboembolic pulmonary hypertension (CTEPH) and tricuspid regurgitation (TR) undergoing pulmonary thromboendarterectomy (PTE), whether concomitant tricuspid annuloplasty should be carried out is still controversial.

Methods

The study population consisted of 45 consecutive patients with CTEPH who were scheduled to undergo PTE. All PTE surgeries were conducted with a median sternotomy and deep hypothermia circulatory arrest (DHCA). We collected and analyzed the demographics, surgical details, echocardiographic parameters, and right heart catheterization (RHC) results of these patients.

Results

Moderate to severe TR was documented in 48.9% (22/45) of the patients pre-operatively and 4.4% (2/45) of the patients post-operatively. In patients with grade 4 TR, severity decreased to grade 2 in 8 and to grade 1 in 1. In patients with grade 3 TR, severity decreased to grade 2 in 9, to grade 1 in 3, and 1 remained unchanged. In patients with grade 2 TR, severity decreased to grade 1 in 8, and 15 remained unchanged. The post-operative TR velocity was decreased significantly (431.9±53.4 vs. 196.5±154.0, P<0.001). Pulmonary artery systolic pressure was 84±17 mmHg pre-operatively and decreased to 38±14 mmHg post-operatively (P<0.001). The pre and post-operative pulmonary diastolic pressure was 29±9 and 17±7 mmHg, respectively (P<0.001). The pre and post-operative mean pulmonary pressure was 48±10 and 24±9 mmHg, respectively (P<0.001). The pulmonary vascular resistance (PVR) (1,025.4±465.0 vs. 476.6±181.2 dynes·sec·cm^-5, P<0.001) and pulmonary artery wedge pressure (PAWP) (9±4 vs. 5±2 mmHg, P<0.001) decreased significantly after operation. The cardiac index (CI) increased significantly (1.9±0.5 vs. 2.3±0.4, P=0.003) after operation.

Conclusions

In conclusion, functional TR could be alleviated after PTE even in patients with high PVR. However, the long-term results need to be further investigated.

Treatment of Tricuspid Regurgitation With the FORMA Repair System

Background: Tricuspid regurgitation (TR) is common and undertreated as the risk of surgery is high in this patient population. Transcatheter devices offer treatment with a lower procedural risk. The FORMA Tricuspid Valve Therapy system (Edwards Lifesciences) will be reviewed here. Device Description: The system combines a spacer placed in the regurgitant orifice and a rail, over which the spacer is delivered, that is anchored to the endocardial surface of the RV. The spacer provides a surface for leaflet coaptation. Outcomes: Eighteen compassionate care patients and 29 patients included in the US EFS trial are reviewed. Patients were elderly (76 years) and high risk (Euroscore 2 was 9.0 and 8.1%, respectively). There were 2 procedural failures in both groups. Mortality at 30 days was 0% in the compassionate group and 7% in the EFS trial. TR was reduced in both groups; 2D/3D EROA 2.1 ± 1.8 to 1.1 ± 0.9 cm² in the EFS trial and vena contracta width 12.1 ± 3.3 to 7.1 ± 2.2 mm. Symptomatic improvement was seen in both groups; the proportion of patients in NYHA class III/IV decreased from 84 to 28% at 30 days in the EFS group, and from 94 to 21% at 1 year, in the compassionate group. Conclusions: Reduction of TR with FORMA system is feasible and sustained. Despite residual TR post-procedure, the significant relative reduction in TR severity contributes to substantial clinical improvements in patients with a FORMA device in place.

Current transcatheter devices to treat functional tricuspid regurgitation with discussion of issues relevant to clinical trial design

Functional or secondary tricuspid regurgitation (TR) has seen increased attention in recent times as relationships with clinically-relevant outcomes have come to light. Despite the association of increased mortality with significant TR, the disease remains under-recognized and thus relatively untreated. In addition, the disease itself has not been extensively studied and the interactions between annular dilatation, right heart disease and pulmonary hypertension are poorly understood. However, the high mortality and recurrence rate with current surgical replacement or repair techniques is well recognised, opening the door to transcatheter therapies for functional TR. The current perspective reviews the rationale for transcatheter solutions, describes some of the current approaches and discusses the ongoing questions of a poorly-studied condition which may limit the design of clinical trials for this disease.