Intra, short and long-term results of mitral VIV for the degenerated surgical mitral prosthesis from italian VIV registry (MIVIV registry)

Abstract Background/Introduction Reoperation of failed bioprosthetic mitral valves is associated with significant morbidity and mortality. Transcatheter mitral valve-in-valve (MViV) replacement was explored early in the development of THVs with transseptal/transfemoral (TS/TF) and transapical (TA) approaches. Purpose This is the first Italian Registry on mitral VIV and it was designed to explore contemporary MViV outcomes with all types of balloon expandable valves. The present study out of the registry aims to asses the >10 years follow-up outcomes in terms of mortality, gender diversity, and perioperative result. Methods Participating centers used standardized definitions to collect clinical information, including patient demographic characteristics, comorbidities, functional status, quality of life indexes, procedural details, and patient outcomes from consecutive MViV cases. Cohort of 265 patients was available for the primary analysis and follow-up too.The patients were grouped by 11 hospitals in Italy performing VIV for degenerated biological mitral prostheses. Results A total of 265 pts underwent mitral VIV due to bioprosthesis degeneration between January 2010 and January 2023. They have been subdivided by transfemoral (TF) with 117 (44%) pts and transapical (TA) with 148 (55,8%) pts. Most of the patients were of female sex (59,2%) and EuroScore II for surgical re-operation was 16.1%. Mixed disease (48%) was more common than mitral regurgitation (29%) and stenosis (22%). 69,8% of the total cohort was in class NYHA III and the mean LVEF was 54%.Otherwise, there were no significant demographic differences between patients undergoing TS and TA. In TF there was more severe PVL (5%)(p-value: 0,001) and much more cases of severe grade of stenosis (54,7%) and regurgitation (57%)(p-value< 0,0001). Considering intraoperative outcomes, technical success has been established in around 97,7% of the total cohort without difference btw groups. Only 3,3% died during hospitalization without difference between groups (P-value=0,735). LVOT obstruction has been seen in 3,4% in the case of TA and 0 for TF. Only 1,5% of the total cohort underwent surgical conversion as well as embolization in only 1,1%. Overall survival from the total cohort was 91,3% at >10 years, Figure 1. Concerning the freedom from cardiac death (CV death) was 96,6% in the total cohort at 13 years. Concerning the difference between access, the general survival is established at 97,4% in TF while 86,3% in TA (p-value =0,050)(Figure 2). Freedom from CV death was 99,1% in TF and 94,5 in TA (p-value=0,209). In gender analysis differentiation, the general survival in females was 98,5% in TF and 85,6% in TA at 13 years (p-value=0,056). Conclusion(s) Transcatheter MViV using a balloon-expandable valve is associated with high technical success, a low complication rate, and a solid long-term benefit in terms of survival. Transseptal access was associated with lower mortality compared with TA access.Figure 1Figure 2