Dr. Zeynep Esra Güner

Name of the study: TRISCEND II Trial:Transcatheter Valve Replacement vs. Optimal Medical Therapy for Severe Tricuspid Regurgitation

Published in Congress: TCT 2024

Link:https://www.tctmd.com/news/triscend-ii-full-results-win-ttvr-severe-tricuspid regurgitation

Introduction:
Severe tricuspid regurgitation is often undertreated due to limited options, leading to significant morbidity and an increased risk of death. Recent advances in transcatheter tricuspid valve interventions offer a promising treatment avenue. The TRISCEND II pivotal trial is the first randomized controlled trial evaluating transcatheter tricuspid valve replacement (TTVR), and data on its outcomes are crucial for understanding its efficacy and safety in this patient population.

Objective:
The aim of this study is to update the TRISCEND II randomized, controlled trial on transcatheter tricuspid valve replacement (TTVR), highlighting the positive effects of treatment in patients with symptomatic, severe tricuspid regurgitation (TR).

Methods:
The TRISCEND II trial is a global, prospective, multicenter, randomized, controlled, pivotal trial to evaluate the safety and effectiveness of the EVOQUE system with optimal medical therapy (OMT) compared with OMT alone in patients with at least severe TR.  The primary composite outcome was hierarchically defined to include any cause of death, the implantation of a right ventricular assist device or heart transplantation, hospitalization for heart failure after the index tricuspid valve intervention, an increase of at least 10 points in the Kansas City Cardiomyopathy Questionnaire overall summary (KCCQ-OS) score, an improvement of at least one functional class according to the New York Heart Association (NYHA), and an enhancement of at least 30 meters in the 6-minute walk test.

Results:
A total of 267 patients were assigned to the valve-replacement group, while 133 patients were placed in the control group. After one year, the win ratio for valve replacement was calculated to be 2.02 (95% confidence interval [CI], 1.56 to 2.62; P<0.001). When comparing pairs of patients, those in the valve-replacement group had a higher number of positive outcomes compared to the control group in several areas: mortality from any cause (14.8% vs. 12.5%), post-index tricuspid valve intervention (3.2% vs. 0.6%), improvements in the KCCQ-OS score (23.1% vs. 6.0%), NYHA class (10.2% vs. 0.8%), and the 6-minute walk test (1.1% vs. 0.9%). However, the valve-replacement group had a lower win ratio concerning the annualized hospitalization rate for heart failure (9.7% vs. 10.0%). Severe bleeding was reported in 15.4% of patients in the valve-replacement group compared to 5.3% in the control group (P=0.003), while new permanent pacemakers were implanted in 17.4% of the valve-replacement group versus 2.3% of the control group (P<0.001).

Conclusions:
In patients with severe tricuspid regurgitation, transcatheter tricuspid valve replacement demonstrated greater efficacy than medical therapy alone for the primary composite outcome, largely due to enhancements in symptoms and quality of life.

Comment:
Updates from the TRISCEND II randomized controlled trial continue to highlight the positive effects of treatment in patients with symptomatic severe TR. In the TRISCEND II study, the benefits of treatment are largely associated with quality of life. Using the Evoque device for TTVR, researchers reported significant improvements in symptoms and quality of life within 1 year. Additionally, compared to OMT, positive outcomes were observed in terms of all-cause mortality, 6-minute walk distance, and hospitalizations for heart failure. For patients with significant coaptation defects and very dilated annuli, TTVR is currently the only available treatment option. While there are concerns regarding valve thrombosis and durability associated with right-sided heart valves, further studies will clarify these issues more definitively.