Left ventricular assist devices have become an important tool in the successful treatment of heart failure as bridges to transplantation. The optimal duration of device support before heart transplantation is debated. We report the effect of left ventricular device support duration on survival after heart transplantation.All patients bridged to heart transplantation with the ThermoCardiosystems Heartmate 1,000 IP left ventricular assist device between January 1, 1986, and October 15, 1994, were included in our study. Parameters studied included duration of support, measures of end-organ function, and complications while supported with the device. Patients supported 30 days before undergoing transplantation.Patients supported for 30 days (p = 0.031). Laboratory values of end-organ function were similar before left ventricular device insertion in both groups, although at the time of transplantation patients supported 30 days (p 30 days had significantly more infections than the 30 days with left ventricular assist devices have improved post-transplant perioperative survival because of normalization of end-organ function and improved physiologic status secondary to aggressive physical rehabilitation. Patients should be supported for > 30 days in combination with physical rehabilitation, to improve early survival after heart transplantation.