New generation software for evaluation of annular dynamics and reverse remodeling after transcatheter repair in patients with severe atrial functional tricuspid regurgitation

Abstract Introduction Functional tricuspid regurgitation (fTR) is the most common cause of TR. The routine imaging method of the right ventricle is 2D echocardiography. CMR is gold standard. 3D echocardiography imaging made RV and tricuspid valve assessment more detailed and comprehensive. Aims to assess if a successful TEER is able to induce some degree of reverse remodelling, defined as a significant reduction of 3D end diastolic and systolic volumes and tricuspid anulus remodeling, defined as a significant reduction in tricuspid area and diameters, with the respect to basal assessment. The primary efficacy endpoint was a TR reduction of at least one grade as assessed by transthoracic echocardiography (TTE) at discharge (procedural success). Methods From April 2022 to June 2023 twenty-five patients underwent tricuspid valve edge-to-edge repair, of which nine patients were excluded. Fifteen patients with secondary atrial TR were performed echocardiographic analysis pre-procedure and within 7 days after procedure and after 6 month followup. 3D tricuspid annulus measurements were gathered using a 4D Auto Tricuspid Valve Quantification software package. Results At baseline all patients had a grade 4 TR or worse according to the new classification system. After TTVR TR was reduced to grade 3 or less in 80% of the patients. Two patients had a reduction of only one grade (both from massive to severe) and one patient had no significant reduction (Fig. 1) The reduction of TR was accompanied by an improvement of symptoms (NYHA class) during follow-up. At baseline 74 % of patients had NYHA class 3, which was reduced to NYHA II in 60 % during follow-up. Right ventricular end diastolic diameter (RVEDD) and end diastolic area decreased respectively from 49 ± 6 mm at baseline to 46 ± 6 mm (p <0.001) at 6 months follow-up (Figure 2A) and 27± 7 cm2/m2 to 23 ±7 cm/m2 (p <0.001). Similarly, right ventricle end-diastolic volume and end-systolic volume decreased from 153 ± 57 ml to 108 ± 43 ml (p = 0.001) (Figure 2B) and from 79+34 ml to 57+ 30 ml (p <0.0001) at baseline and 6-months respectively. Significant changes were observed in the morfphology of tricuspid anulus after triclip repair. Tricuspid annulus area, antero-posterior diameter and sfericity index were respectively decreased at 6 months follow up from 17,2±4.1 % to 13,4±3,1 % , from 43±6 mm to 37.5 mm and from 88 ±6 mm to 81±6 mm. All above had p <0.001. Conclusions The main findings are: (1) TEER is effective and durable in reducing TR; (2) positive structural right chamber reverse remodelling occurs soon after the procedure; and (3) sustained improvements in clinical status, quality of life and no evidence of re-hospitalisation up to six months were seen in our patients. The resulting echocardiographic improvements indicate tricuspid valve leaflet approximation does not just significantly reduce the grade of TR, but also affects adjacent structures and improves right ventricular afterload adaptation.