The atrial neoannulus technique for mitral valve replacement in patients with severe mitral annular calcification.

Objectives: Mitral valve replacement (MVR) in patients with severe mitral annular calcification (MAC) remains technically challenging because of the risk of annular disruption and associated complications. We report short-term outcomes of a novel surgical approach that creates an atrial neoannulus for prosthetic valve implantation in high-risk patients with severe mitral stenosis or mixed disease. Methods: Between September 2021 and January 2025, 27 consecutive patients with severe MAC underwent MVR at a tertiary referral center. A median sternotomy and interatrial groove approach were used to access the mitral valve. The anterior leaflet was excised, whereas the posterior leaflet was left intact with minimal decalcification. Pledgetted sutures were placed anteriorly along the annulus, incorporating the anterior leaflet cuff and posteriorly through the atrial wall, away from the heavily calcified posterior annulus. This technique created a neoannulus within the atrial tissue to anchor the prosthetic valve. Results: The median patient age was 64.1 years, with 74.1% of the patients being female. Chronic kidney disease stage ≥3 was present in 51.9%, and 29.6% were reoperations. Preoperative median mitral valve gradient was 13 mm Hg. The median prosthetic valve size was 29 mm. In-hospital mortality was 7.4% (2 patients), both requiring renal replacement therapy. One late noncardiac death occurred (3.7%) at a median follow-up of 5 months. One patient (3.7%) required reintervention for left ventricular perforation, and 2 (7.4%) developed minor paravalvular leaks. At last follow-up, the median mitral valve gradient was reduced to 5 mm Hg. Conclusions: Atrial neoannulus construction is a feasible MVR technique in severe MAC with acceptable short-term outcomes.