Outcomes of rescue procedures in patients undergoing unsuccessful deployment of transcatheter mitral valve replacement

Perivalvular leak (PVL), valve embolization, and migration of valve in mitral position are critical complications of transcatheter mitral valve replacement (TMVR). To date, rescue strategies, and outcomes following unsuccessful initial TMVR deployment remain poorly documented. Between March 2016 and December 2024, 86 patients with high risk of open-heart surgery underwent TMVR with a balloon expandable valve at a single institution. 19.8% (17/86) of patients experienced unsuccessful first TMVR (unsuccessful group) due to valve embolization, migration, significant PVL, or pericardial effusion, whereas 80.2% (69/86) had successful first TMVR (successful group). We evaluated postoperative outcomes comparing unsuccessful to successful groups. Among 17 patients with unsuccessful first TMVR, 70.6% (12/17) underwent additional valve deployment, with successful valve-in-valve implantation in 75.0% (9/12). 17.6% (3/17) developed valve embolization in left atrium after transcatheter rescue procedures or additional valve deployment failed, subsequently 66.7% (2/3) required emergent surgical explantation of embolized valves, 33.3% (1/3) was managed medically due to prohibitive surgical risk. Surgical patients were discharged home without complications. Early mortality in unsuccessful group was 29.4% (5/17) and 13.0% (9/69) in successful group. There was no significant difference in early mortality between the 2 groups ( p = 0.10). Median follow-up term was 10 months. Cumulative survival rate in 12 months was 50.5% in unsuccessful group, and 60.0% in successful group. Mid-term outcomes were similar between the 2 groups ( p = 0.34). The study was underpowered to detect differences in all-cause mortality, but unsuccessful deployment was associated with substantially higher numerical early mortality and significantly higher cardiac mortality.