Open Atrial Transcatheter Mitral Valve Replacement in Patients With Mitral Annular Calcification.

Background: Mitral valve replacement in the setting of severe mitral annular calcification remains a surgical challenge. Transcatheter mitral valve replacement (TMVR) using an aortic balloon-expandable transcatheter heart valve is emerging as a potential treatment option for high surgical risk patients. Transseptal, transapical, or transatrial access is not always feasible, so an understanding of alternative implantation techniques is important.

Objectives: The authors sought to present a step-by-step description of a contemporary transatrial TMVR technique using balloon-expandable aortic transcatheter heart valves. This procedure has evolved over time to address valve migration, left ventricular outflow tract obstruction, and paravalvular leak. The authors present a refined technique that has been associated with the most reproducible outcomes.

Methods: A step-by-step description of the TMVR technique and outcomes of 8 patients treated using this technique are described. Baseline patient clinical and echocardiographic characteristics and 30-day post-TMVR outcomes are presented.

Results: Eight patients underwent transatrial TMVR at a single institution. Five had previous cardiac surgery. Mean STS score was 8%. Technical success by MVARC (Mitral Valve Academic Research Consortium) criteria was 100%. There was zero in-hospital and 30-day mortality. Procedural success by MVARC criteria at 30 days was 100%. Paravalvular leak immediately post-implant was none or trace in 6 and mild in 1.

Conclusions: The technique described is reproducible and was associated with favorable outcomes in this early experience. It represents a useful technique for the treatment of mitral valve disease in the setting of severe annular calcification. A structured and defined implantation technique is critical to investigators as this field evolves.