Department for Pediatric Cardiac Surgery, University Hospital Erlangen, Erlangen, Germany.
Eur J Cardiothorac Surg. 2010 Jul;38(1):78-85. doi: 10.1016/j.ejcts.2010.01.044. Epub 2010 Mar 12.
The longevity of valved right ventricle to pulmonary artery (RV-PA) conduits is limited due to calcification and degeneration of non-viable structures. Xenografts are commonly used because of the restricted availability of cryopreserved homografts. Tissue-engineered (de-cellularised) pulmonary valves (TEPVs) were thought to be a valuable alternative to cryopreserved pulmonary homografts due to postoperative seeding with viable autologous vascular endothelial cells.
From July 2007 to December 2008, xenogenous TEPV (Matrix P plus) were implanted in 16 patients in the right ventricular outflow tract for different indications, related to congenital heart disease. Mean age at operation was 14+/-11 years, including three patients younger than 1 year. The median conduit size was 22 mm (range: 13-26 mm).
The early and late survival rates were 100%. At a median follow-up of 10 months (range: 2-17 months), six patients (38%) had to be re-operated upon due to obstructed grafts. Five of these patients were older than 13 years (range: 13-26 years); one patient was younger than 1 year. On echocardiography before re-operation, mean systolic gradient in the main PA was 66+/-18 mmHg. In explanted conduits, we found a predominantly peripheral conduit narrowing without leaflet calcification. Histological examination revealed stenosis formation, due to inflammatory infiltration and severely fibrogenic pseudo-intimal reaction.
On the basis of our short-term results, the Matrix P plus de-cellularised tissue-engineered pulmonary valve cannot be regarded as an ideal conduit for right ventricular outflow tract reconstruction, as the widespread use of these grafts may increase the possibility of frequent early conduit failures.
由于不可存活结构的钙化和退化，带瓣右心室至肺动脉（RV-PA）管道的寿命有限。由于冷冻同种移植物的供应有限，异种移植物通常被使用。由于术后可与活的自体血管内皮细胞播种，组织工程（去细胞化）肺动脉瓣（TEPV）被认为是冷冻同种肺动脉移植物的有价值的替代品。
从 2007 年 7 月至 2008 年 12 月，16 名患者因先天性心脏病的不同适应证在右心室流出道植入了异种 TEPV（Matrix P plus）。手术时的平均年龄为 14+/-11 岁，包括 3 名年龄小于 1 岁的患者。中值管道大小为 22 毫米（范围：13-26 毫米）。
早期和晚期存活率均为 100%。在中位随访 10 个月（范围：2-17 个月）期间，由于移植受阻，有 6 名患者（38%）需要再次手术。这 5 名患者年龄大于 13 岁（范围：13-26 岁）；1 名患者年龄小于 1 岁。在再次手术前的超声心动图检查中，主肺动脉的平均收缩期梯度为 66+/-18mmHg。在取出的管道中，我们发现主要是外周管道狭窄，没有瓣叶钙化。组织学检查显示狭窄形成，原因是炎症浸润和严重的纤维形成假性内膜反应。
根据我们的短期结果，Matrix P plus 去细胞组织工程肺动脉瓣不能被视为右心室流出道重建的理想管道，因为这些移植物的广泛使用可能会增加早期频繁发生移植物失败的可能性。
