Re-repair of the left atrioventricular valve in atrioventricular septal defects: the morphologic approach to the role of Gore-tex band reduction annuloplasty

Abstract

Incompetence of the left atrioventricular valve remains the final Achilles' heel of repair of atrioventricular septal defects (AVSDs), despite low operative mortality in the modern era. We have analysed the morphological basis for valvar incompetence in our own series of repairs, and in doing so, reviewed the morphology of the annulus in AVSDs, before and after surgical repair. We reviewed retrospectively re-repair operations of the left atrioventricular valve following previous repair of AVSDs at the Great Ormond Street Hospital from 1 January 1994 to 31 December 2007. From this case series, the reasons for valvar incompetence were identified and techniques used for re-repair recorded. We also incorporated the detailed morphology of the annulus of the left atrioventricular valve before and after repair from our cardiac morphology archive. Thirty-three patients had undergone re-repair of the left atrioventricular valve between 1 January 1994 and 31 December 2007. Twenty patients underwent re-repair of the left atrioventricular valve within 1 year of initial repair, and 13 cases beyond 1 year after repair. Cases re-repaired within 1 year mainly did so as a result of leaflet tears or valvar dysplasia. Cases re-repaired after this time mainly had multiple areas of valvar leakage, including central incompetence. Two patients underwent a second re-repair, which were dealt with by a partial ring from a thin-wall Gore-Tex graft for reduction annuloplasty. Out of the 121 cardiac morphologic specimens, 53 had undergone previous complete repair. Following repair, the annulus of the new left atrioventricular valve was composed of artificial patch material on its septal portion. Left atrioventricular valve incompetence following previous repair usually involves repair of the zone of apposition between the left bridging leaflets. Many of these valves also require annuloplasty to attain competence. Given the shape, growth potential and morphologic composition of the annulus in these cases, we have performed some of these repairs with a partial flexible ring from a thin-walled 3.5-mm Gore-Tex graft as a reduction annuloplasty that can be shaped to fit the exact contours of this annulus.