Temporal outcomes of transcatheter mitral valve replacement in native mitral valve disease with annular calcification

Background: Surgical intervention in patients with native mitral disease due to severe mitral annular calcification (MAC) carries significant risk. Transcatheter mitral valve replacement (TMVR) using balloon-expandable aortic transcatheter heart valve (THV) in MAC had emerged as alternative treatment.

Objectives: We aim to study the temporal change in clinical outcomes of the procedure at a single center.

Methods: We retrospectively studied 23 patients who underwent TMVR in MAC at Mayo Clinic from January, 14, 2014 to March, 15, 2019. Cases were divided into early (n = 11) and late (n = 12) experience. The primary end point was 30-day all-cause mortality. The secondary end points were immediate technical success, 30-day procedural success, and 1-year all-cause mortality.

Results: Mean age of patients was 75.2 ± 8.9 years and 17 (74.0%) were female. Median STS score for 30-day mortality was 8 (Interquartile range 4.3-13.4) for the entire population. Immediate technical success was achieved in 21 out of 23 patients (two failures in the early experience were related to tamponade and procedural death). Thirty-day procedural success was higher in the late experience (10 out of 12 patients) compared to early experience (5 out of 11 patients, p = .06). Four deaths in the first 30-days were observed in the early experience while all patients survived to hospital discharge in the late experience (p = .01).

Conclusions: Procedural success and 30-day survival of transcatheter mitral valve replacement in severe mitral annular calcification procedure using balloon-expandable aortic prosthesis had improved over the years. This is likely attributed to significant advancement in procedural planning, valve design, and techniques.