Background. We compared mitral repair to replacement in patients with chronic ischemic mitral regurgitation (IMR), due to left ventricular dysfunction (LV-IMR) or papillary muscle infarction (PM-IMR). Methods. Patients with IMR undergoing repair (n = 65) or replacement (n = 137) from 1990 to 2001 were evaluated. There were 87 patients with LV-IMR, and 115 patients with PM-IMR. Patients presenting in cardiogenic shock were excluded. Outcomes were evaluated by Cox survival analysis with propensity score adjustment and bootstrap validation. Results. Survival at 3, 5, and 9 years was, respectively, 0.94, 0.79, and 0.63 in the repair group, and 0.73, 0.67, and 0.59 in the replacement group. The hazard ratio (HR) of death for mitral repair versus replacement was not constant over the period of follow-up. Repair was associated with better early survival in the PM-IMR group, with an adjusted HR of 0.25 (95% confidence interval: 0.09 to 0.71) at 1 year. In the LV-IMR group and in patients with PM-IMR with high acuity and comorbidity, there was no significant survival advantage associated with repair. The beneficial effect of repair was not evident at late follow-up in either group. These findings were independent of the surgeon. Need for reoperation was more common after repair than after replacement (14% versus 3%, p 0.003). Conclusions. Patients with PM-IMR benefit from mitral repair with a significantly better early survival. However, the benefit of repair is not evident at longer follow-up. There was a nonsignificant trend toward greater early survival among patients with LV-IMR who underwent repair. (c) 2005 by The Society of Thoracic Surgeons.