Abstract 695: The Quality Of Cell Isolation Determines Left Ventricular Contractile Recovery After Intracoronary Administration Of Bone Marrow-derived Progenitor Cells In Patients With AMI - Insights from the REPAIR-AMI Trial
The REPAIR-AMI trial demonstrated that intracoronary (i.c.) infusion of bone marrow-derived progenitor cells (BMC) in patients (pts) with AMI is associated with a significantly greater recovery of left ventricular contractile function (LVEF) after 4 months compared to i.c. infusion of placebo. Since cell isolation procedures affect BMC function, we investigated whether the quality of isolated BMC determines LVEF recovery.
Methods: For all REPAIR-AMI pts, quality of cell isolation was assessed by measuring total number of BMC, CD34+, CD133+ cells, and their migratory capacity towards SDF-1 (migration). BMC viability and contamination of purified BMC with red blood cells (RBC) were quantified.
Results: Contamination of BMC with RBC significantly (r = −0.24, p < 0.001) correlated with reduced BMC viability. As expected, none of the BMC quality parameters correlated with changes in LVEF in the placebo group (n = 92). In the BMC group, LVEF increase was inversely correlated with the number of contaminating RBC (r = −0.25, p < 0.02, n = 94). BMC migration normalized for RBC contamination was closely correlated (r = 0.33, p < 0.001) with the increase in LVEF after 4 months (figure⇓). On multivariate analysis, the migration of BMC normalized for RBC contamination (p = 0.02) and reduced baseline LVEF (p = 0.03) were the only significant predictors of an increase in LVEF.
Conclusion: In REPAIR-AMI, quality of isolation and functionality of purified BMC after the isolation procedure determine the extent of LV contractile recovery after i.c. BMC infusion in AMI, thus documenting an association between functionality of infused BMC and clinical outcome, suggestive of a cause-effect relationship.