6-P

Aim VADs are increasingly used as a bridge to transplantation and are implicated as a risk factor for allosensitization. We investigated in a matched case-control study the association between VAD and PRA changes (peak & significant increase ⩾20%). Methods We analyzed records of VAD recipients at our institute from 00-09 (n = 384) and included patients with pre-VAD PRA testing and another PRA test within 6 months post-VAD (n = 100). PRA testing was performed by screening flowPRA beads (One Lambda, CA). A control group was constructed from heart transplant candidates evaluated in the same time frame with no VAD (n = 830) for whom we had ⩾3 PRA tests within 8 months pre-transplant (n = 445). Two controls were randomly matched for each VAD case based on yr of initial PRA test. Results Follow-up was longer in the controls (median:103 vs 33; p Table 1 ). Multivariable models adjusted for gender, race, pre-VAD PRA, duration of VAD and blood transfusion yet the associations remained unchanges. Of VAD patients, that had a significant increase in C1 PRA and single antigen testing performed 81% (35/43) showed development of new HLA antibody specificities post-VAD. Conclusions Our results suggest that VAD is associated with CI allosensitization independent of other risk factors. These findings have important clinical implications and warrant prospective studies to better understand VAD associated allosensitization.