Clinical outcomes of mitral valve intervention in patients with mitral annular calcification: A systematic review and meta-analysis.
BACKGROUND
Mitral valve (MV) disease with mitral annular calcification (MAC) poses a surgical challenge and the clinical outcomes of MV surgery as well as transcatheter mitral valve replacement (TMVR) remain relatively unexplored. We performed a systematic review and meta-analysis to assess the effects of MAC on clinical outcomes following MV surgery and TMVR.


METHODS
We searched MEDLINE and EMBASE databases until February 2019 for studies comparing clinical outcomes of MV surgery or TMVR in patients with and without MAC. Data were extracted by two independent investigators. Outcomes were perioperative and midterm complications and mortality.


RESULTS
Seven observational studies enrolling 2902 patients were included. MAC patients were older, more likely to be female with greater chronic lung disease and kidney failure. Perioperative mortality was similar between patients with and without MAC undergoing MV surgery (risk ratio [RR], 1.15; 95% confidence interval [CI], 0.50-2.65; P = .74). MAC was associated with a higher risk of bleeding, permanent pacemaker implantation, and periprosthetic leak. Midterm mortality was greater in MAC patients undergoing MV surgery (incident rate ratio [IRR], 1.32; 95% CI, 1.05-1.67; P = .02). MAC patients undergoing TMVR had higher perioperative (RR, 4.65; 95% CI, 2.93-7.38; P < .01) and 1-year (RR, 5.44; 95% CI, 3.49-8.49; P < .01) mortality, decreased procedural success, greater left ventricular outflow tract obstruction and need for conversion to surgery when compared with patients undergoing TMVR for dysfunction of a bioprosthetic valve or annuloplasty ring.


CONCLUSION
MV procedures in patients with MAC are associated with higher mortality and morbidity. This is largely driven by the high-risk patient profile associated with MAC. TMVR holds promise but has important limitations and should be reserved for select patients.
['Ribeiro|Roberto V P|RVP|http://orcid.org/0000-0003-0906-0539', 'Yanagawa|Bobby|B|', 'Légaré|Jean-François|JF|', 'Hassan|Ansar|A|', 'Ouzounian|Maral|M|', 'Verma|Subodh|S|', 'Friedrich|Jan O|JO|']
D002114:Calcinosis D005260:Female D006349:Heart Valve Diseases D019918:Heart Valve Prosthesis Implantation D006801:Humans D008297:Male D008943:Mitral Valve D012306:Risk D015996:Survival Rate
mitral annular calcification meta-analysis transcatheter mitral valve replacement mitral valve surgery valve repair/replacement