• mitral valve disease
• SMVR
• Tendyne
• TMVR

Abstract
Objectives: This study evaluates the mid-term clinical and echocardiographic outcomes of patients undergoing SMVR or TMVR with the Tendyne system in a single-center European experience.
Methods: All consecutive high-risk patients undergoing TMVR with the Tendyne System or SMVR at the University of Pisa, Itay, between March 2018 and December 2023 were included. The primary outcome was cardiovascular (CV) survival at FU and secondary outcome was overall survival and rehospitalization for HF at latest FU.
Results: A total of 30 Tendyne TMVR and 50 SMVR patients were analyzed. The mean age was 75 ±7 and 70±10 years for TMVR and SMVR respectively. TMVR patients presented worse renal function at baseline (eGFR 44,98±18,81 and 56,60±26,64 ml/min respectively) respect to SMVR. The two groups had similar EuroSCORE II (7,75±7,81 and 6,91±11,68% for TMVR and SMVR respectively) and STS scores (8,34±7,35 and 8,48±12,8% for TMVR and SMVR respectively). LV ejection fraction (LVEF) was lower in the TMVR group with respect to SMVR (42±13 and 57±10 %, respectively). Thirty-day CV mortality was lower in TMVR (p.=0.055). At a median FU of 1.92 years, overall mortality was 37.5% and 50% in SMVR and TMVR patients (p=0.277), while CV mortality was 25% and 33% in SMVR and TMVR groups, respectively (p=0.496). The number of new hospitalizations for HF was similar between groups. At univariate analysis the type of procedure did not impact on CV and overall survival (HR 1.67, 95% CI 0.82-3.41, p=0.157 for overall and HR 1.57, 95% CI 0.66-3.73, p=0.311 for CV). PVL rate was low in both groups and mean transmitral gradient remained low in SMVR group and TMVR group, however in the TMVR group it significantly decreased respect to discharge (2.8±1.6 and 3.7±1.0 mmHg respectively, p=0.003). LVEF remained stable in the TMVR group and improved in the SMVR group while RV function remained stable, either for TMVR and SMVR. TR tended to worsen more in the SMVR group than in the TMVR group (42% and 15%, p=0.101).
Conclusions: SMVR and TMVR have similar early and mid-term outcomes in a high-risk population with comparable mid-term echocardiographic results. TMVR provides lower postoperative complication rates and faster recovery in frail high-risk patients. Therefore, TMVR might be a valuable alternative to surgery is selected high-risk patients.