Acute fulminant hemolysis after transcatheter mitral valve replacement for mitral annular calcification

Transcatheter mitral valve replacement (TMVR) is emerging as an alternative treatment strategy to surgery for patients with severe mitral annular calcification (MAC) who are not candidates for traditional mitral valve surgery. Paravalvular leak (PVL) is common following TMVR for severe MAC and can lead to heart failure symptoms and/or intravascular hemolysis, the latter of which usually is clinically stable. We report the case of a 67‐year‐old woman with symptomatic severe aortic stenosis and mitral stenosis with MAC in the setting of prior chest irradiation who was treated initially with transcatheter aortic valve replacement followed by TMVR at a later date (Sapien S3 system; Edwards Lifesciences). Immediately following TMVR, she developed acute profound hemolysis which manifested with hemoglobinuria, transfusion‐dependent anemia, and acute renal failure requiring renal replacement therapy. She was treated with post‐dilation balloon valvuloplasty after failed transcatheter PVL closure 10 days following TMVR with resulting improvement in the PVL. The hemolytic anemia resolved and renal function recovered without the need for continued hemodialysis 2 months later and stabilization of glomerular filtration rate at 6 months. This case highlights a potential severe complication of TMVR in MAC and suggests that improvement in hemolysis and late recovery of renal function may occur following treatment of PVL.