Grabitz R G, Freudenthal F, Sigler M, Le T P, Boosfeld C, Handt S, von Bernuth G
Department of Pediatric Cardiology and Interdisciplinary Center of Clinical Research on Biomaterials, Aachen University of Technology, Germany.
J Am Coll Cardiol. 1998 Mar 1;31(3):677-83. doi: 10.1016/s0735-1097(98)00025-4.
We sought to evaluate the efficacy and tissue reaction of a new miniature interventional device for occlusion of large patent ductus arteriosus (PDA) in a neonatal lamb model.
A variety of devices are used to close PDAs by interventional measures. Spring coils found to have a high cumulative occlusion rate have thus far been limited to smaller PDAs because of the physical limitation of grip forces.
Memory-shaped double-cone stainless steel coils with enhanced stiffness of the outer rings by a double-helix configuration were mounted on a titanium/nickel core wire. A snap-in mechanism attaches the coil to the delivery wire, allowing intravascular coil retrieval and repositioning. The system was placed through a 4F or 5F Teflon catheter. A chronic lamb model (n = 8) of PDA (>5 mm) was used in which ductus patency was secured by a protocol of repetitive angioplasty procedures. The animals were killed after 1 to 181 days, and the ductal region was examined by inspection as well as by light and electron microscopy.
Placement of the coils within the PDA was possible in all lambs. Before final detachment, the coils were retrieved or repositioned, or both, up to 12 times. In all but one animal the ductus was closed within 6 days after the procedure. The coils caused no infections or aortic and pulmonary artery obstruction. Histologic and electron microscopic studies revealed endothelial coverage of the implants but no foreign body reaction or local or systemic inflammation or erosion of the implant.
The device effectively closed large PDAs in our model and may overcome the previous limitations of coils. Clinical trials are indicated.
我们试图在新生羔羊模型中评估一种用于封堵大型动脉导管未闭（PDA）的新型微型介入装置的疗效和组织反应。
多种装置用于通过介入措施关闭PDA。由于握持力的物理限制，迄今发现具有高累积闭塞率的弹簧圈仅限于较小的PDA。
通过双螺旋结构增强外环刚度的记忆形状双锥不锈钢圈安装在钛/镍芯线上。一种卡扣机制将线圈连接到输送线上，允许血管内线圈回收和重新定位。该系统通过4F或5F聚四氟乙烯导管放置。使用PDA（>5mm）的慢性羔羊模型（n = 8），其中通过重复血管成形术方案确保导管通畅。在1至181天后处死动物，并通过检查以及光镜和电镜检查导管区域。
所有羔羊均可将线圈放置在PDA内。在最终脱离之前，线圈最多可回收或重新定位12次。除一只动物外，所有动物在手术后6天内导管均闭合。线圈未引起感染或主动脉和肺动脉阻塞。组织学和电子显微镜研究显示植入物有内皮覆盖，但没有异物反应或局部或全身炎症或植入物侵蚀。
该装置在我们的模型中有效地关闭了大型PDA，可能克服了先前线圈的局限性。需要进行临床试验。
