BACKGROUND Papillary muscle (PM) suspension concomitant with mitral annuloplasty and PM approximation (PMA) has been developed for functional mitral regurgitation (MR). In the present study, the early effect of PM suspension (PMS) on the postoperative mitral geometry and diastolic mitral tethering was investigated. RESULTS Subjects were 22 patients with left ventricular dysfunction and functional MR who underwent mitral annuloplasty and PMA with or without suspension from 2004 to 2008. The purpose of PMS is to maintain the mitral complex geometry and prevent future mitral tethering caused by left ventricular remodeling. The mean age was 64 +/-10 (range 39-85) years. The submitral apparatus geometry was measured by echocardiography. PM and mitral inflow angles in the anterior-directional suspension group were significantly larger than those in the posterior-directional suspension group (57 +/-7 degrees vs 46 +/-9 degrees , P=0.017 and 78 +/-9 degrees vs 60 +/-6 degrees , P<0.001, respectively), which were comparable to the normal control. In the posterior-directional suspension group, the transmitral pressure gradient was higher and restrictive mitral filling pattern remained postoperatively in 2 cases of the group. CONCLUSIONS Anterior-directional suspension is preferable to the posterior one in terms of diastolic mitral filling.