Impact of Right Ventricular to Pulmonary Artery Coupling on Survival Following Indirect Mitral Annuloplasty

Background: Right ventricular-to-pulmonary artery (RV-PA) coupling is an important predictor of long-term survival following transcatheter edge-to-edge repair. However, its impact on survival in patients undergoing indirect mitral annuloplasty is unknown. The study aimed to assess the impact of baseline RV-PA coupling on survival following indirect mitral annuloplasty in heart failure patients. Methods: Patients were classified according to baseline RV-PA coupling: TAPSE (tricuspid annular plane systolic excursion)/PASP (pulmonary artery systolic pressure) > 0.55 (group 1), <= 0.55 >= 0.32 (group 2) and <= 0.32 (group 3). Clinical follow-up and RV function were assessed 3 and 12 months following indirect annuloplasty. Results: A TAPSE/PASP > 0.55 was found in 19 patients, while 47 patients showed a TAPSE/PASP <= 0.55 > 0.32 and 26 a TAPSE/PASP <= 0.32. A significant reduction in vena contracta and regurgitant volume compared to baseline was found in all groups at 3-months and 12-months follow-up. One-year mortality was significantly increased in group 3 compared to the other groups (group 1: 0.95, group 2: 0.91, group 3: 0.77; Log-Rank test p = 0.018). In groups 2 and 3 the TAPSE/PASP significantly improved during the 12-months follow-up, while it remained unchanged in group 1 (group 1: baseline = 0.71 +/- 0.03, 12-months = 0.67 +/- 0.01; group 2: baseline = 0.43 +/- 0.06, 12-months: 0.56 +/- 0.04; group 3: baseline = 0.25 +/- 0.06, 12-months: 0.4 +/- 0.03; p < 0.001). Conclusions: RV-PA uncoupling before indirect mitral annuloplasty is associated with poor survival. However, Carillon device implantation improved right heart function and RV-PA coupling in patients with severe RV dysfunction at baseline. Therefore, Carillon device implantation can be a valuable option for transcatheter treatment of patients with FMR and right heart failure.