Qinglong Zeng1, Xiang Zhou1, Yunjun He1, Xiaohui Wang1, Tao Shang1, Yangyan He1, Ziheng Wu1, Hongkun Zhang2, Donglin Li3. 1. Department of Vascular Surgery, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China. 2. Department of Vascular Surgery, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China. Electronic address: 1198050@zju.edu.cn. 3. Department of Vascular Surgery, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China. Electronic address: lidonglin@zju.edu.cn.
Abstract
BACKGROUND: To evaluate the quality of in vitro fenestrations during in situ fenestration (ISF) and investigate the differences between needle and laser puncture in current stent-grafts. METHODS: An in vitro study evaluated the damage created by needle ISF on stent-graft fabrics versus laser ISF. Fenestrations were made in 5 different commercially available stent-grafts, including polyester stent-grafts (Relay, Valiant and Hercules) and expanded polytetrafluoroethylene (ePTFE) stent-grafts (TAG and Ankura). Each stent-graft received fenestration by needle and laser separately, followed by gradual dilation (4 mm, 6 mm, 8 mm, and 10 mm sequentially) of noncompliant balloons. Quantitative and qualitative evaluations including fenestration diameter, area, shape and margins were conducted using light microscopy and scanning electron microscope. RESULTS: The primary fenestrations created by needle were slit-like with visible cut-off fibers in polyester stent-grafts and were almost circular with clear margins in ePTFE stent-grafts; those created by laser were squared or elliptical with ragged edges and burned fibers in all the stent-grafts. Fabric debris and toxic particles due to burning of the material were generated during laser-assisted fenestration. The Primary holes in polyester stent-grafts (Relay, Valiant and Hercules) by needle showed smaller area (0.05 mm2 vs. 0.22 mm2, 0.52 mm2 vs. 0.70 mm2 and 0.28 mm2 vs. 0.46 mm2; P < 0.01) and worse shape (0.93 vs. 2.46, 1.17 vs. 2.33 and 0.93 vs. 2.47; P < 0.01) than those by laser, while larger area (0.67 vs.0.43, 0.59 vs.0.45; P < 0.05), better shape (3.93 vs. 2.53, 3.90 vs. 2.93; P < 0.05) and better margin (3.83 vs. 2.47, 3.83 vs. 2.53; P < 0.05) in ePTFE stent-grafts (TAG and Ankrura). After gradual balloon dilation, the final holes showed no evident difference in maximal length, fenestration area, scores of shape and margin between the 2 ways of fenestration (P > 0.05). Ankura stent-graft showed the largest holes with best quality than the others. CONCLUSIONS: The primary fenestrations were different between needle and laser puncture, laser induced fabric debris and toxic particles release should be cautiously considered. The final fenestrations were similar after gradual balloon dilation.
BACKGROUND: To evaluate the quality of in vitro fenestrations during in situ fenestration (ISF) and investigate the differences between needle and laser puncture in current stent-grafts. METHODS: An in vitro study evaluated the damage created by needle ISF on stent-graft fabrics versus laser ISF. Fenestrations were made in 5 different commercially available stent-grafts, including polyester stent-grafts (Relay, Valiant and Hercules) and expanded polytetrafluoroethylene (ePTFE) stent-grafts (TAG and Ankura). Each stent-graft received fenestration by needle and laser separately, followed by gradual dilation (4 mm, 6 mm, 8 mm, and 10 mm sequentially) of noncompliant balloons. Quantitative and qualitative evaluations including fenestration diameter, area, shape and margins were conducted using light microscopy and scanning electron microscope. RESULTS: The primary fenestrations created by needle were slit-like with visible cut-off fibers in polyester stent-grafts and were almost circular with clear margins in ePTFE stent-grafts; those created by laser were squared or elliptical with ragged edges and burned fibers in all the stent-grafts. Fabric debris and toxic particles due to burning of the material were generated during laser-assisted fenestration. The Primary holes in polyester stent-grafts (Relay, Valiant and Hercules) by needle showed smaller area (0.05 mm2 vs. 0.22 mm2, 0.52 mm2 vs. 0.70 mm2 and 0.28 mm2 vs. 0.46 mm2; P < 0.01) and worse shape (0.93 vs. 2.46, 1.17 vs. 2.33 and 0.93 vs. 2.47; P < 0.01) than those by laser, while larger area (0.67 vs.0.43, 0.59 vs.0.45; P < 0.05), better shape (3.93 vs. 2.53, 3.90 vs. 2.93; P < 0.05) and better margin (3.83 vs. 2.47, 3.83 vs. 2.53; P < 0.05) in ePTFE stent-grafts (TAG and Ankrura). After gradual balloon dilation, the final holes showed no evident difference in maximal length, fenestration area, scores of shape and margin between the 2 ways of fenestration (P > 0.05). Ankura stent-graft showed the largest holes with best quality than the others. CONCLUSIONS: The primary fenestrations were different between needle and laser puncture, laser induced fabric debris and toxic particles release should be cautiously considered. The final fenestrations were similar after gradual balloon dilation.