Correction of Mitral Incompetence in Atrioventricular Canal Defects with Double-Orifice Mitral Valve: The Triple-Orifice Repair

Abstract

Results of corrective surgery in patients with atrioventricular canal defects and an incompetent double-orifice mitral valve are often suboptimal for residual mitral incompetence or new mitral stenosis. A new technique has been developed and used in two patients (2 and 14 years old), both with a severely incompetent double-orifice mitral valve and a partial form of atrioventricular canal defect.

Since in both patients the valve was incompetent at the cleft site centrally (in the proximity of the free edge of the leaflets) only the central part of the cleft was approximated by stitches, while the rest of the cleft was left open. This type of repair created a triple-orifice mitral valve (the third orifice being between the central part of the valve and the base of the cleft) and was effective in abolishing completely the incompetence without producing stenosis.

The experience with these two patients, who are perfectly well 2 years and 16 months postoperatively, demonstrates that, at least in some patients, the presence of a double-orifice mitral valve can be neutralized as an incremental risk factor in the repair of atrioventricular canal malformations.