Clinical outcomes comparison between patients with residual severe and moderate-or-less tricuspid regurgitation after percutaneous edge-to-edge repair: which degree of reduction is significant?
Authors: Patrascu I A , Binder D , Schnabel P , Schneider J , Staehle W , Risha O , Weinmann K , Ott I 
Published: November 2023

Abstract

Introduction
Transcatheter tricuspid valve repair (TTVR) for high-grade regurgitation (TR) is an emerging option in inoperable patients, and can improve quality of life. Based on the new 5-grade TR classification(1), all studies have defined procedural success by at least one-grade reduction. While a higher degree of TR reduction should translate into better clinical outcomes, considerable reduction is not always possible. Most often, the regurgitant area is too large for coaptation devices, frequently 2- to 3-fold greater than in mitral regurgitation (MR). Difficult periprocedural guidance, suboptimal acoustic window, shadowing from pacemaker leads, leaflets with multiple scallops contribute to less than perfect results. This study compared long-term clinical outcomes of edge-to-edge TTVR in patients with residual severe TR (STR; III/V) vs moderate-or-less TR (MTR; ≤II/V), despite procedural success.

Methods
Eligible inoperable patients had chronic symptomatic functional TR despite diuretic therapy. Exclusion criteria were treatable left heart e.g., significant MR, and pulmonary arterial pressure ≥70mmHg, among others. The primary efficacy endpoint was at least one grade TR reduction at 30 days. The secondary endpoints related to long-term improvement in symptoms, quality of life and multiorgan function. Follow-up was carried out between January 2021 and January 2023.

Results
Forty-three patients, 51% females, had ≥severe (III/V) functional TR, 65% of them massive (IV/V) and 14% torrential (V/V). Mean age was 81.8±4.9 years, with 10.8±6.3% STS-Score. Patients were highly symptomatic e.g., 86% in NYHA stage III-IV, and multimorbid e.g., the majority had advanced kidney and liver disease. The primary efficacy endpoint was recorded in 91% of all patients, with 100% technical success and no device related complications. According to the degree of residual TR we defined 3 subgroups: STR (n=17), MTR (n=22), and no reduction (n=4). Two- or more-grade reduction was present in 91% of MTR and 24% of STR cases(Figure 1). By 12 months, 6 patients died, 2 from each group, 3 of non-cardiac cause. MACE rate was 18.6%. Long-term outcomes in the remaining 15 STR and 20 MTR patients were compared(Figure 2). Improvement in initial NYHA class III/IV occurred in 54% of STR and 77% of MTR patients. KCCQ Score increased by 21.6±17.9 pts. (p&lt;0.001) vs 29.8±15.6 (p&lt;0.001), six-minute walk test by 103.3±65.7 meters (p&lt;0.001) vs 117.5±93.2 (p&lt;0.001). Renal and liver function equally improved in both groups [GFR 51.3±16.5ml/min/1,73m2 to 56.4±21.6 (p=0.043) vs 59.9±17 to 60.1±18.2 (p=0.930); AST 27.4±9.9U/L to 22.2±6.9 (p=0.009) vs 37.5±26.9 to 29.7±10.3 (p=0.112)].

Conclusions
Although TTVR should always aim for trace to mild TR, considerable reduction is not always possible. This study indicates that even one-grade TR reduction can significantly impact quality of life, functional capacity and multiorgan involvement, similarly in STR and MTR patients.Figure_1Figure_2