Preclinical comparative assessment of a dedicated pediatric poly-L-lactic-acid-based bioresorbable scaffold with a low-profile bare metal stent.

BACKGROUND: Polymer-based bioresorbable scaffolds (PBBS) have been assessed for coronary revascularization with mixed outcomes. Few studies have targeted pediatric-specific scaffolds. We sought to assess safety, efficacy, and short-term performance of a dedicated drug-free PBBS pediatric scaffold compared to a standard low-profile bare metal stent (BMS) in central and peripheral arteries of weaned piglets.
METHODS: Forty-two devices (22 Elixir poly-L-lactic-acid-based pediatric bioresorbable scaffolds [BRS] [6 × 18 mm] and 20 control BMS Cook Formula 418 [6 × 20 mm]) were implanted in the descending aorta and pulmonary arteries (PAs) of 14 female Yucatan piglets. Quantitative measurements were collected on the day of device deployment and 30 and 90 days postimplantation to compare device patency and integrity.
RESULTS: The BRS has a comparable safety profile to the BMS in the acute setting. Late lumen loss (LLL) and percent diameter stenosis (%DS) were not significantly different between BRS and BMS in the PA at 30 days. LLL and %DS were greater for BRS versus BMS in the aorta at 30 days postimplantation (LLL difference: 0.96 ± 0.26; %DS difference: 16.15 ± 4.51; p < .05). At 90 days, %DS in the aortic BRS was less, and PA BRS LLL was also less than BMS. Histomorphometric data showed greater intimal proliferation and area stenosis in the BRS at all time points and in all vessels.
CONCLUSIONS: A dedicated PBBS pediatric BRS has a favorable safety profile in the acute/subacute setting and demonstrates characteristics that are consistent with adult BRSs.