Mitral Annular Calcification: Operative Decision Making and Technical Considerations

Mitral annular calcification (MAC) presents a formidable challenge in mitral valve surgery owing to risks of atrioventricular groove disruption, circumflex artery injury, and paravalvular leaks. The optimal operative strategy varies according to the severity of annular calcification, extent of ventricular extension, and the patient-specific risk profile.

A narrative expert review was performed synthesizing contemporary surgical series, imaging-guided approaches, and transcatheter strategies for mitral valve intervention in the setting of MAC. Technical considerations, complication avoidance strategies, and decision-making frameworks were integrated into a new severity-based operative algorithm.

We developed a decision matrix to stratify patients into four categories to guide preoperative planning and operative decisions. MAC management lies on a spectrum between working around the MAC with no resection ("respect" the MAC) to complete MAC resection with atrioventricular groove reconstruction ("resect" the MAC). Severe or circumferential MAC demands tailored strategies, including transcatheter or hybrid approaches. In patients with mild MAC, mitral valve repair remains feasible and preferred. Moderate MAC requires individualized decision-making; repair is achievable when leaflet mobility is preserved, and decalcification permits secure annuloplasty. Replacement is favored when leaflet restriction or annular rigidity precludes durable reconstruction. The extent of decalcification should be tailored to the patient's risk profile and surgical expertise to ensure durable results.

Mitral valve intervention in the setting of MAC requires an individualized approach. We propose a practical management algorithm, stratified by patient risk and anatomic feasibility.