Impact of FLuid OverlOaD on outcomes after Transcatheter Tricuspid Valve Interventions (FLOOD-TTVI)

Background: Transcatheter tricuspid valve interventions (TTVI) have emerged as effective treatment strategies for patients with severe tricuspid regurgitation (TR) that provide substantial improvements in symptoms and quality of life. Fluid overload (FO) is a hallmark symptom of TR that may negatively impact feasibility of TTVI due to right heart dilation. Hence, current practice guidelines recommend preprocedural intravenous diuretic therapy for patients with severe FO undergoing TTVI. Whether patients with mild FO have worse outcomes after TTVI has not yet been systematically investigated.

Objective: To assess the impact of mild FO on outcomes after TTVI.

Methods: Consecutive patients with severe TR undergoing TTVI at our center were prospectively enrolled in this study. FO was quantified by bioimpedance spectroscopy (BIS) using a portable, CE marked device (Body Composition Monitor, Fresenius Medical Care, Bad Homburg, Germany) that evidently enables precise and reproducible measurements of FO. Postprocedural imaging endpoints and clinical outcomes were compared between patients with FO <1.0 l and ≥1.0 l, a threshold that has been previously established and validated as an appropriate cut-off value for mild FO.

Results: Among 52 patients included in this study, 21 patients (40%) displayed mild FO. At baseline, patients with and without FO did not differ in terms of age, sex, bodyweight, utilization of intravenous diuretics, TR grade, right ventricular (RV) and left ventricular systolic function, inferior vena cava diameter, RV and right atrial pressures determined by right heart catheterization, NYHA class and Minnesota Living With Heart Failure Questionnaire (MLHFQ) score. Patients with FO had higher pitting edema score (1.5 vs. 0.9 on a scale from 0 to 4, p = 0.02), higher basal RV diameter (46.4 vs. 42.4 mm, p = 0.04), lower cardiac index (2.4 vs. 3.1 ml/min/m2, p = 0.02), lower mixed venous oxygen saturation (65.8 vs. 72.5%, p = 0.01), and were more frequently treated with SGLT2 inhibitors (28.6 vs. 6.5%, p = 0.05) prior to the procedure than patients without FO. Safety endpoints did not differ significantly between the groups. In both groups, TR grade was substantially lower at the 30-day follow-up visit compared to baseline (mean TR grade FO: 2.0 vs. 3.71 at baseline, p < 0.0001, and no FO: 1.4 vs. 3.77 at baseline, p < 0.0001), but patients with FO displayed higher residual TR grades than patients without FO (mean TR grade 2.0 vs. 1.4, p = 0.01; Fig. 1A). Patients with and without FO showed significant reverse RV remodeling (Fig. 1B), and improvements in NYHA class as well MLFHQ score (Fig. 1C and D) at the 30-day follow-up visit, which did not differ between the groups. Two patients (both without FO at baseline) were hospitalized within 30 days after the procedure. There was no mortality.

Conclusions: TTVI was safe and effective in patients with mild FO. However, postprocedural TR grades were slightly higher in patients with FO compared to those without FO which might translate to worse outcomes on long-term follow up. Collectively, our data therefore encourage preprocedural decongestive therapy to achieve the lowest possible state of FO prior to TTVI.