Biphasic Right Ventricular Reverse Remodeling Following Tricuspid Valve Transcatheter Edge-to-Edge Repair

Transcatheter tricuspid valve edge-to-edge repair (T-TEER) has been reported to be associated with right ventricular reverse remodeling (RVRR). Data on the temporal evolution of this phenomenon are scarce. The aim of this study was to evaluate RVRR over the course of 2-year follow-up after T-TEER using sequential 3-dimensional echocardiograms (3DE). The study included T-TEER patients with available 3DE at baseline and discharge. Further follow-ups were scheduled at 1 month, 6 months, as well as 1 and 2 years. The 3DE evaluation included right ventricular volumes (right ventricular end-diastolic volume [RVEDV3D]; right ventricular end-systolic volume [RVESV3D]), right ventricular ejection fraction (RVEF3D), and RV longitudinal strain of the free wall and the septum. The study included 231 patients (median age 82 [IQR: 79-86] years, 48% women). We observed a biphasic pattern of RVRR following T-TEER consisting of early RV volume unloading (phase 1, reduced RVEDV3D) and later structural remodeling (phase 2, reduced RVESV3D). Whereas RVEDV3D was significantly reduced early after the procedure (-9.7% from baseline to discharge; P < 0.001), RVESV3D remained unchanged at 1-month follow-up. Reduction in RVESV3D was observed at 6-month follow-up for the first time (-5.4% from baseline to 6-month follow-up; P < 0.001). Reduction in both RVEDV3D and RVESV3D peaked at 1-year follow-up and remained stable until 2 years after T-TEER. RV function declined early after T-TEER and gradually increased over the course of follow-up (RVEF3D at baseline 42.2% ± 8.9%, discharge 31.1% ± 9.4%, 2-year follow-up 41.6% ± 8.9%). The 3D RV longitudinal strain of the septum and 3D RV longitudinal strain of the free wall developed analogously. RVRR following T-TEER occurs in 2 stages and involves early RV unloading (reduction in RVEDV3D) and later structural RVRR (reduction in RVESV3D) with an improvement in RVEF.