Department of Cardiothoracic Surgery, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Department of Pathology, University Medical Center Utrecht, Utrecht, The Netherlands.
Department of Cardiothoracic Surgery, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Department of Cardiothoracic Surgery, University Medical Center Utrecht, Utrecht, The Netherlands.
J Thorac Cardiovasc Surg. 2020 Oct;160(4):e201-e215. doi: 10.1016/j.jtcvs.2019.09.164. Epub 2020 Jan 10.
Decellularized extracellular matrix made from porcine small intestinal submucosa, commercially available as CorMatrix (CorMatrix Cardiovascular, Inc, Roswell, Ga) is used off-label to reconstruct heart valves. Recently, surgeons experienced failures and words of caution were raised. The aim of this study was to evaluate decellularized porcine small intestinal submucosa as right-sided heart valved conduit in a xenogeneic animal model.
A pulmonary valve replacement was performed with custom-made valved conduits in 10 lambs and 10 sheep (1 month [3 lambs and 3 sheep], 3 months [3 lambs and 3 sheep], 6 months [4 lambs and 4 sheep]). Valve function was assessed after implantation and before the animal was put to death. Explanted conduits were inspected macroscopically and analyzed using immunohistochemistry and scanning electron microscopy. They also underwent mechanical testing and testing for biochemical composition.
All valved conduits were successfully implanted. Five sheep and 2 lambs died due to congestive heart failure within 2 months after surgery. In the animals that died, the valve leaflets were thickened with signs of inflammation (endocarditis in 4). Five sheep and 8 lambs (1 month: 6 out of 6 animals, 3 months: 4 out of 6 animals, 6 months: 3 out of 8 animals) survived planned follow-up. At the time they were put to death, 5 lambs had significant pulmonary stenosis and 1 sheep showed severe regurgitation. A well-functioning valve was seen in 4 sheep and 3 lambs for up to 3 months. These leaflets showed limited signs of remodeling.
Fifty percent of sheep and 20% of lambs died due to valve failure before the planned follow-up period was complete. A well-functioning valve was seen in 35% of animals, albeit with limited signs of tissue remodeling at ≤3 months after implantation. Further analysis is needed to understand the disturbing dichotomous outcome before clinical application can be advised.
脱细胞猪小肠黏膜下层基质（CorMatrix 心血管公司，美国佐治亚州罗斯韦尔）是一种商业上可获得的产品，被用于心脏瓣膜的重建，属于超说明书使用。最近，外科医生遇到了一些失败案例，并提出了警告。本研究旨在评估脱细胞猪小肠黏膜下层作为右心瓣膜管状移植物在异种动物模型中的应用。
在 10 只羔羊和 10 只绵羊中进行了定制带瓣管状移植物的肺动脉瓣置换术（1 个月[3 只羔羊和 3 只绵羊]、3 个月[3 只羔羊和 3 只绵羊]、6 个月[4 只羔羊和 4 只绵羊]）。在植入后和动物死亡前评估瓣膜功能。取出的移植物进行大体检查，并进行免疫组织化学和扫描电子显微镜分析。还进行了机械测试和生化成分测试。
所有带瓣管状移植物均成功植入。5 只绵羊和 2 只羔羊在手术后 2 个月内因充血性心力衰竭死亡。在死亡的动物中，瓣膜瓣叶增厚，伴有炎症迹象（4 例心内膜炎）。5 只绵羊和 8 只羔羊（1 个月：6 只动物中的 6 只，3 个月：6 只动物中的 4 只，6 个月：8 只动物中的 3 只）存活至计划的随访期。在处死时，5 只羔羊出现明显的肺动脉瓣狭窄，1 只绵羊出现严重反流。4 只绵羊和 3 只羔羊的瓣膜功能良好，最长可达 3 个月。这些瓣叶显示出有限的重塑迹象。
50%的绵羊和 20%的羔羊由于瓣膜失效在计划的随访期之前死亡。35%的动物的瓣膜功能良好，尽管植入后≤3 个月时组织重塑迹象有限。在临床应用之前，需要进一步分析以了解这种令人不安的二分法结果。
