Minimally overlapping technique of bioresorbable scaffolds in a porcine coronary artery model: proof-of-concept study.

Overlapping stent placement is a common approach for treating long coronary artery disease, but is associated with increased risks of restenosis and thrombosis. This preliminary study evaluated the efficacy and safety of a minimally overlapping technique using bioresorbable scaffolds (BRSs) compared with the conventional overlapping technique in a porcine coronary artery model. Eight coronary arteries were randomly assigned to two groups. In the overlapping group, two BRSs overlapped by 2.4 mm. In the end-to-end group, both ends of the BRSs were minimally overlapped, guided by balloon and scaffold markers. Lesions were assessed through phantom study, coronary angiography, optical coherence tomography, and histological analysis. Technical success was achieved in both groups. Strut fractures were observed in the overlapping group but not in the end-to-end group. BRS-induced neointimal tissue formation related variables were significantly lower in the end-to-end group (all p < 0.001). Apoptotic cells were significantly reduced in the end-to-end group compared with the conventional overlapping group (p < 0.001). The minimally overlapping technique using BRSs effectively maintained luminal patency and structural integrity for 4 weeks, suggesting that the end-to-end method may be a favorable strategy for treating long diffuse coronary lesions.