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.