Guiding Early Management in Severe Mitral Stenosis with Extensive Mitral Annular Calcification: A Transseptal ViMAC Case

: Mitral annular calcification (MAC) related mitral stenosis (MS) presents a significant therapeutic challenge, especially in patients considered high-risk or inoperable. Transcatheter mitral valve replacement (TMVR) has emerged as an alternative, but the procedure remains technically demanding due to anatomical complexities and the risk of complications. We report the case of a 72-year-old man with severe MAC and MS, who successfully underwent TMVR using a 29 mm Edwards Sapien 3 valve. A key innovation in this case was the implementation of a novel balloon-assisted trackability assessment to optimize the trajectory of the delivery system. Prior to septostomy, a noncompliant balloon was positioned and inflated at the mitral level, enabling real-time evaluation of coaxial alignment and confirming the feasibility of advancing the prosthesis along the intended path. Once optimal trajectory was verified, the same balloon was used to perform the septostomy, ensuring accurate and controlled passage of the delivery system, and ultimately facilitating precise implantation. At 3-year follow-up, the patient remained asymptomatic with a well-functioning valve and stable hemodynamics. This case highlights the value of preseptostomy balloon-based trackability assessment as a simple yet highly effective technique to enhance procedural precision in TMVR for MAC.