Abstract
BACKGROUND: The tricuspid regurgitation (TR) syndrome, based on the extent of cardiac and extracardiac involvement, is a newly proposed staging method to evaluate the progression of TR. This study aimed to explore cardiac structural characteristics and the short-term prognosis after transcatheter tricuspid valve replacement (TTVR) in patients at different stages. METHODS: A post-hoc analysis of patients enrolled in the first-in-man and confirmatory study and an investigator-initiated trial of the LuX-Valve Plus system was conducted. Patients with TR who underwent successful TTVR by the LuX-Valve Plus systems were staged according to systemic involvement. The baseline and one-month follow-up results among different stages were compared. RESULTS: A total of 149 patients were included, of whom 23 were in stage 2, 49 were in stage 3, and 77 were in stage 4. Compared with patients in stages 2 and 3, patients in stage 4 had more severe TR (mean vena contracta width: 14.94±4.51 vs. 11.13±4.56 vs. 11.04±3.71 mm, P<0.001), greater right ventricular (RV) remodeling (RV anterior-posterior diameter, 35.63±6.04 vs. 32.35±4.95 vs. 33.56±4.43 mm, P=0.007) and annulus enlargement (tricuspid annulus, 44.87±5.41 vs. 41.54±6.21 vs. 42.13±5.26 mm, P=0.004), higher level of N-terminal pro-brain natriuretic peptide (NT-Pro-BNP) [1,063.50 (541.25, 1,791.25) vs. 631.50 (462.55, 1,409.50) vs. 587.50 (250.55, 908.55) pg/mL, P=0.03], and more extracardiac system damage [such as more lower limbs edema, higher bilirubin level and Model for End-Stage Liver Disease (MELD)-albumin score, lower hemoglobin, platelet count, and estimated glomerular filtration rate (eGFR)]. Regardless of staging, patients generally benefited from TTVR as evidenced by reverse RV remodeling, improved New York Heart Association (NYHA) classification, and improved Kansas City Cardiomyopathy Questionnaire (KCCQ) scores. Patients in stage 4 had a higher incidence of paravalvular leakage after the procedure and all deaths were presented in the stage 4 group. No heart failure readmission was observed during short-term follow-up. CONCLUSIONS: The staging of TR syndrome may help to quantify disease severity. Although all patients can gain short-term benefits from TTVR, an early intervention may help to reduce the incidence of complications.