Abstract 17004: Intramyocardial Injection of Gelatinized Capillary-Alginate Hydrogel Enhances Recovery of LV Function Post-MI
We have developed a new injectable biomaterial composed of gelatinized capillary-alginate hydrogel. This degradable gel, termed CapGel-GT, forms a unique microstructure of parallel capillary-like channels. The diameter and density of the channels can be adjusted to facilitate cell, tissue and blood vessel ingrowth (Fig. 1A). Accordingly, via a 28G needle CapGel-GT was injected into the antero-septal left ventricular (LV) wall of normal rats (n=14) and the infarct border zone following permanent LAD ligation in rats with MI (n=65). LV function was assessed (echo) 48hrs following MI (week 0), at 4 weeks, and at 8 weeks. Control animals received no treatment following MI. CapGel-GT injection was not associated with increased mortality. Fractional shortening (FS) for rats receiving CapGel-GT was significantly higher at both week 4 and 8 echo assessments compared to week 0 as well as compared to FS of the control group animals at week 4 and 8 (Fig. 1F). Fractional area change was also significantly higher in the CapGel-treated animals at week 8 (54%) compared to controls (43%, p=0.009). Histology showed that CapGel-GT was well integrated and vascularized at week 4 (Fig. 1B,C) and largely bioabsorbed by week 8 (Fig. 1D). CapGel-GT intramyocardial injection therefore appears to be safe post-MI and associated with improved post-MI LV function. Figure 1. (A) Micrograph of CapGel-GT sectioned perpendicular to channel long axis, (B) α-smooth muscle actin positive blood vessels (green) within CapGel-GT at week 4, (C) Trichrome stained LV wall showing CapGel-GT area (black outline) at week 4, (D) week 8 and (F) Fractional shortening for infarcted hearts with and without CagGel-GT intramyocardial injection. Significant differences from week 0 indicated by “*” and from control by “**”.
- © 2012 by American Heart Association, Inc.