Cardiac regeneration strategies using stem cells have shown variable and inconsistent results with respect to patient cardiac function and clinical outcomes. There has been increasing consensus that improving the efficiency of delivery may improve results. The Helix transendocardial delivery system (BioCardia Inc.) has been developed to enable percutaneous transendocardial biotherapeutic delivery. Therefore, we evaluated cell retention using this unique system compared with direct transepicardial injection and intracoronary infusion in an animal model.
Twelve healthy swine were used in this study. 18Fluorodeoxyglucose (FDG)-labeled bone marrow mononuclear cells were delivered via percutaneous transendocardial route using the Helix system (TE group, n = 5), via direct transepicardial injection using a straight 27-gauge needle in an open chest procedure (TP group, n = 4), or via percutaneous intracoronary (IC) infusion (IC group, n = 3). One hour after cell delivery, the distribution of injected cells within the myocardium was assessed by PET-CT. Regions of interest were defined and their signals were compared in each group. Retention rates were calculated as a percentage of the comparing signal.
The distribution of injected cells in the myocardium was higher in the TE group (17.9%) than in the TP group (6.0%, versus TE, P < 0.001) and the IC group (1.0%, versus TE, P < 0.001). Consistent with previous reports, there were signal distributions in the lungs, liver, and kidneys in qualitative whole body PET assessment.
TE cell delivery using a helical infusion catheter is more efficient in cell retention than either TP delivery or IC delivery using PET-CT analysis.