Jux C, Bertram H, Wohlsein P, Bruegmann M, Fink C, Wueboldt P, Paul T, Hausdorf G
Department of Pediatric Cardiology and Pediatric Intensive Care Medicine, Hannover Medical School, Carl Neuberg Strasse 1, D-30625 Hannover, Germany.
J Interv Cardiol. 2001 Jun;14(3):309-12. doi: 10.1111/j.1540-8183.2001.tb00337.x.
Devices used in interventional cardiology are permanent implants. However, most of the devices fulfill only a temporary function. For example, atrial septal defect (ASD) occluders serve as mechanical shields until complete in- and overgrowth of the occluding device by endogenous tissue from the defect edges has occurred. Thereafter, the foreign body material of the devices is no longer needed and bears potential long-term adverse effects. The concept of "biodegradable" occluder devices that act as transient mechanical shields to close the defects and as scaffolds for overgrowth with autologous tissue is, therefore, tempting. Since rapid and complete ingrowth as well as coverage by firm tissue is a prerequisite for any such "biological" occluder devices, the feasibility and short-term in vivo response to STARFlex devices preceeded with autologous cells was studied in an experimental sheep model. The experiments demonstrated that autologous cell preceeding of cardiovascular implants is technically feasible. Cells survived the mechanical stress of device implantation. A precoating of conventional STARFlex occluders led to an increased cellular density after cell seeding of the device, an increased resistance of the precultured cytolayer against mechanical stress, and a significantly higher poststress viability of "implanted" cells. Experimental closure of ASD using autologous-cell preseeded STARFlex devices was uncomplicated. In the sheep model this led to rapid, complete, and firm ingrowth of the device into the adjacent atrial tissue. A thicker layer of young fibrous granulation tissue in organization was found on the preceeded devices compared with the unseeded control group after 4 weeks in vivo. Currently, an increased thrombogenicity limits in vivo application.
介入心脏病学中使用的装置是永久性植入物。然而，大多数装置仅发挥临时功能。例如，房间隔缺损（ASD）封堵器作为机械屏障，直到封堵装置被缺损边缘的内源性组织完全内生和过度生长。此后，装置的异物材料不再需要，并存在潜在的长期不良影响。因此，“可生物降解”封堵器装置的概念很有吸引力，这种装置可作为临时机械屏障来闭合缺损，并作为自体组织过度生长的支架。由于快速、完全的内生以及被坚实组织覆盖是任何此类“生物”封堵器装置的先决条件，因此在实验性绵羊模型中研究了预先接种自体细胞的STARFlex装置的可行性和短期体内反应。实验表明，心血管植入物预先接种自体细胞在技术上是可行的。细胞在装置植入的机械应力下存活。传统STARFlex封堵器的预涂层导致装置接种细胞后细胞密度增加，预培养细胞层对机械应力的抵抗力增加，以及“植入”细胞在应激后的活力显著提高。使用预先接种自体细胞的STARFlex装置对ASD进行实验性闭合并不复杂。在绵羊模型中，这导致装置快速、完全且牢固地内生到相邻心房组织中。在体内4周后，与未接种细胞的对照组相比，预先接种细胞的装置上发现有更厚的一层正在机化的年轻纤维肉芽组织。目前，血栓形成性增加限制了其在体内的应用。
