Positive Outcomes in TRISCEND II Trial Highlight Benefits of Transcatheter Tricuspid Valve Replacement for Severe Tricuspid Regurgitation

An update to the TRISCEND II randomized, controlled trial on transcatheter tricuspid valve replacement (TTVR) highlights the positive impact of treatment for patients with symptomatic, severe tricuspid regurgitation (TR).

The primary outcome, measured by the win ratio, favored TTVR using the Evoque device (2.02; 95% CI 1.56-2.62). Patients demonstrated improvements in symptoms, function, and quality of life at 1 year. Additionally, TTVR resulted in fewer deaths from all causes and reduced hospitalizations for heart failure (HF) compared to those receiving optimal medical therapy (OMT), mainly diuretics.

Results showed a “near elimination of TR,” sustained over 1 year. Findings from 30 days and 6 months in the first 150 patients led to US approval of the Evoque TTVR system earlier this year, following European approval in late 2023.

Investigators noted significant quality-of-life improvements despite the absence of a sham control, with Kansas City Cardiomyopathy Questionnaire (KCCQ-OS) scores after TTVR showing substantial changes, sustained over a year. If the gains were placebo-driven, improvements would likely not continue beyond 6 months.

The absence of a sham control was noted, but differences between right-sided and left-sided interventions were acknowledged. Managing high-dose diuretic therapy remains challenging for patients seeking better quality of life.

The TRISCEND II trial, covering 267 patients in the TTVR group and 133 in the OMT group across 45 international sites, showed that 70% of patients had NYHA class III/IV symptoms, and over 92% had atrial fibrillation.

Early risks with TTVR included cardiovascular mortality within 30 days at 3.1%, severe bleeding at 10.4%, and a 24.7% rate of new pacemaker/CIED implantation. In contrast, the OMT arm reported no deaths and a 1.5% severe bleeding rate.

The primary endpoint encompassed all-cause mortality, HF hospitalizations, and improvements in KCCQ-OS, NYHA class, and 6-minute walk distance. Overall, TTVR showed benefits across all subgroups, with all-cause mortality at 12.6% for TTVR versus 15.2% for OMT.

With Evoque now commercially available, further assessment of mortality benefits is complex as patients may switch from OMT to TTVR. Some experts advocate waiting beyond 2 years before switching to assess long-term mortality effects fully.

Quality-of-life analysis involving 392 patients found substantial gains in KCCQ-OS scores. At 1 year, 57.6% of TTVR patients showed moderate improvement in KCCQ, and 39.5% showed large improvements. Further validation in the Tri-QOL study confirmed KCCQ’s effectiveness in capturing symptoms, particularly dyspnea and fatigue.

In related research, patients with severe TR treated with transcatheter edge-to-edge repair (TEER) also showed quality of life improvements. With options like Evoque for TTVR and TriClip for TEER, patients with severe TR now have more treatments available.

The choice between TEER and TTVR depends on physician preference and patient anatomy. TEER may be limited for patients with large coaptation gaps or dilated annuli, where TTVR is often the preferred option. For many, the choice relies on operator expertise and clinical judgment.