Echocardiographic assessment of the mechanisms of correction of bileaflet prolapse causing mitral regurgitation with only posterior leaflet repair surgery

Recent data suggest that posterior leaflet repair alone corrects mitral reg urgitation in patients with bileaflet prolapse and normal anterior chordae, The purpose of this study was to use echocardiography to define the anatom ic differences between posterior and bileaflet prolapse and to determine if posterior leaflet repair alone leads to correction of bileaflet prolapse, We studied patients who underwent quadrangular resection of the posterior m itral valve leaflet to treat bileaflet prolapse (group I, n = 20) or isolat ed posterior leaflet prolapse (group II, n = 20), Echocardiographic charact eristics were compared before and after the procedure. There were no differ ences in the left ventricular end-diastolic or end-systolic dimensions or f unction between the 2 groups. However, anterior leaflet length was greater in patients with bileaflet prolapse (3.3 +/- 0.6 cm vs 2.6 +/- 0.4 cm, p = 0.003), In group I, posterior leaflet repair changed anterior leaflet displ acement from -0.8 +/- 0.2 to 0.5 +/- 0.4 cm (p <0.001) and posterior leafle t displacement from -0.8 +/- 0.3 cm below to 0.5 +/- 0.4 cm (p <0.001) in f ront of the mitral annular plane. In group II, anterior leaflet displacemen t was unchanged from 0.2 +/- 0.1 to 0.3 +/- 0.2 cm (p = 0.22), whereas post erior leaflet displacement changed from -0.7 +/- 0.2 to 0.4 +/- 0.2 cm (p < 0.001), Thus, patients with bileaflet prolapse and no ruptured chards have excessive anterior leaflet length. In such patients, posterior leaflet rep air alone corrects anterior and posterior leaflet prolapse. (C) 2000 by Exc erpta Medica, Inc.