Background and aim of the study: Mitral annular calcification (MAC) occurs mainly at the posterior half of the annulus, and is often seen in dialysis-dependent patients who have a high risk for cardiac surgery. A simple supra-annular prosthesis insertion ('half-and-half') technique was applied to five dialysis patients with extensive MAC to prevent catastrophic complications.
Methods: Five dialysis patients with extensive MAC underwent mitral valve replacement (MVR) using the 'half-and-half' technique. In all patients, everted mattress sutures were anchored to the left atrial wall just around the posterior half of the calcified annulus with minimum debridement, while horizontal mattress sutures were placed from the left ventricular side to the left atrial side on the non-calcified anterior half of the annulus. In one patient with an entirely calcified annulus who underwent double valve replacement, the anterior MAC was removed through the aorta to enable mitral valve sutures to be placed on the annulus. St. Jude Medical (SJM) valves were secured in the supra-annular position in all patients.
Results: No valve dysfunction was observed in any patient. Among the four hospital survivors, there were no valve-related events, except for a trivial paravalvular leak in one patient, during follow up periods ranging from 11 to 33 months.
Conclusion: This simple supra-annular prosthesis insertion technique was safely and easily performed with minimum debridement of the calcified annulus in five dialysis patients. The technique may represent an alternative approach for high-risk patients with extensive MAC. The SJM valve, with its hinge protruding into the atrial side, is suitable for use in this technique.