A) Purpose of Study: Cell attachment on a polymer is a critical step when tissue engineering cardiovascular structures. It has been reported that hydrolysis of polyglycolic acid (PGA) mesh by exposure to sodium hydroxide increases cell attachment. This study examines the effect of this treatment on smooth muscle cell (SMC) attachment to a PGA, poly-4-hydroxybuterate (P4HB) composite scaffold. B) Methods: One-cm2 disks of PGA dip-coated in 1% P4HB were prepared. In a first set of experiments, smooth muscle cells (SMC) were delivered onto untreate disks (n=3) and disks treated for 1 minute in 1 M NaOH and then for 2 hours in fetal bovine serum (FBS) (n=3). After six hours the constructs were vacuum died an weighed, and total DNA content per disk was assayed. In a second set of experiments, SMC were delivered onto untreated disks (n=3), disks treated for 1 minute in NaOH (n=3), disks treated for 2 hours in FBS (n=3) and disks treated for minute in NaOH and then 2 hours in FBS (n=3). An alamarBlue® proliferatio assay was used to assess the cell viability and proliferation of SMC on each disk After six days, each disks was vacuum dried and weighed, and total DNA conten was measured. In a third set of experiments, SMC were delivered onto disks treate in 1M NaOH for 1, 3, 5 and 10 minutes. An alamarBlue® proliferation assay was performed. After six days DNA content was measured. Mass analysis and scannin electron microscopy (SEM) was used to assess the effects of NaOH on each dis after 1, 5 and 10 minutes. C) Results: A difference in total DNA content could no be detected between untreated and treated groups after 6 hours (p=0.43) or between the untreated group and any of the treatment combinations after 6 days (NaOH group, p=0.93; FBS group, p=0.30; NAOH and FBS group, p=0.97). A difference in total DNA content after 6 days could not be detected between disks treated with NaOH for different lengths of time (1 min., p=0.12; 3 min., p=0.70; 5min., p=0.18 10min., p=0.19). Treatment with NaOH for 1,5 and 10 minutes reduced the fiber diameter PGA on the disks by 4%, 40% and 62% respectively. Mass analysis showed a comparable decrease in total mass. In conclusion, NaOH treatment of PGA, 1%P4HB composite disks does not affect cell attachment or proliferation Furthermore, surface degradation of PGA fibers by NaOH increases with treatment over time resulting in a decrease in total mass and PGA fiber diameter.