Background: Different coaptation devices are available for transcatheter edge-to-edge repair in tricuspid regurgitation (TEER-TR).  By closing the coaptation device a considerable tractive force is applied on the leaflets of the tricuspid valve (TV), which has an effect on the valve ring. Aim of the study was to compare the active closing TriClip system with the spring-based, passive closing device Pascal Ace in regard to the impact on TV dimensions.

Methods: Out of 166 TEER-TR procedures with different devices we retrospectively formed patient pairs with comparable baseline tricuspid ring dimensions and identical number of devices implanted during procedure. Patients of group 1 received TriClip G3/G4 and group 2 was treated with Pascal Ace. During the procedure 3D zoom loops of tricuspid valve were acquired before and after device placement using transoesophageal echocardiography. Measurements of TV ring dimensions included the following parameters: ring area (TV area), maximal diameter, minimal diameter, eccentricity index (Figure 1). In addition, regurgitation severity was graded from 1+ to 5+ by measuring vena contracta area (VCA 3D) in 3D full volume colour Doppler loop using multiplanar reconstruction.  Right atrial (RA) and ventricular volumes (RVVD, RVVS) and function (RV EF) were assessed in a 3D full volume loop.

Results: In the overall group (n = 54) a TR grade ≤2+ after TEER-TR was achieved in 81.5 % of cases.  Each device related group comprised 27 patients. As expected, TV ring and right ventricular cavity dimension where comparable between groups (Table 1). Device implantation resulted in a significant reduction of TV ring area in both groups (Figure 2).  The absolute and percentage reduction in TV ring area was significant higher in the group 1 (TriClip) compared to the group 2 (Pascal Ace). The absolute reduction of TV ring area showed an only modest correlation to the number of implanted coaptation devices (r=0.35, p<0.001) and percentage reduction of VCA 3D (r =0.42, p<0.001).

Conclusion:  TEER-TR reduces TV ring dimensions and this effect is device type dependent.