Abbas Jonathan Raihan, Hoschtitzky J Andreas
Congenital Heart Surgery, Adult Congenital Heart Disease Unit, Central Manchester Foundation Trust, Manchester UK.
Interact Cardiovasc Thorac Surg. 2013 Nov;17(5):854-60. doi: 10.1093/icvts/ivt332. Epub 2013 Aug 8.
A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: which is the best tissue valve for use in the pulmonary position, late after previous repair of tetralogy of Fallot? Altogether 141 papers were found using the reported search, of which 13 represented the best evidence to answer the clinical question. In addition to this, 1 paper was found by searching the reference lists of the relevant papers. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude from the best evidence available that homograft valves function well in the pulmonary position late after Tetralogy of Fallot (TOF) repair. This is particularly evident in the larger studies where the patients were only treated with homografts. It has been suggested that Homografts are better than xenografts and this has not been statistically shown. Two articles have suggested that xenografts outperform homografts however, in both studies these results were not statistically significant. Furthermore, early indications suggest that porcine valves may be better than bovine pericardial valves but a better longer term follow-up is certainly required to demonstrate this. It is important to realize also that when comparing the effectiveness of these valves in the pulmonary position, one cannot ignore confounding factors. The most important of these include timing of operation, age of patient, valve size, immunological factors, operative complexity and also postoperative valvular gradients. The timing of these operations has always been an area of great controversy illustrated by varied guidelines. There is no general consensus regarding whether there is even a role of pulmonary valve replacement late after TOF repair. Further weakening any conclusions that may be drawn based on current best evidence is the lack of strong follow-up data (transvalvular gradients and right ventricular (RV) volumetric data). New research is required with comparisons using objective clinical parameters in order to more effectively answer our clinical question.
根据结构化方案撰写了一篇心脏外科的最佳证据主题文章。所探讨的问题是：在法洛四联症既往修复术后晚期，用于肺动脉位置的最佳组织瓣膜是哪种？通过报告的检索共找到141篇论文，其中13篇代表了回答该临床问题的最佳证据。除此之外，通过检索相关论文的参考文献列表又找到1篇论文。现将这些论文的作者、期刊、发表日期、国家、研究的患者群体、研究类型、相关结局和结果制成表格。我们从现有最佳证据得出结论，同种异体移植瓣膜在法洛四联症（TOF）修复术后晚期的肺动脉位置功能良好。这在规模较大的研究中尤为明显，这些研究中的患者仅接受了同种异体移植瓣膜治疗。有人认为同种异体移植瓣膜优于异种移植瓣膜，但这尚未得到统计学证明。有两篇文章表明异种移植瓣膜优于同种异体移植瓣膜，然而，在这两项研究中这些结果均无统计学意义。此外，早期迹象表明猪瓣膜可能优于牛心包瓣膜，但当然需要更好的长期随访来证实这一点。同样重要的是要认识到，在比较这些瓣膜在肺动脉位置的有效性时，不能忽视混杂因素。其中最重要的因素包括手术时机、患者年龄、瓣膜大小、免疫因素、手术复杂性以及术后瓣膜梯度。这些手术的时机一直是一个极具争议的领域，各种指南对此都有不同的说明。对于TOF修复术后晚期是否甚至需要进行肺动脉瓣置换，目前尚无普遍共识。基于当前最佳证据可能得出的任何结论，因缺乏强有力的随访数据（跨瓣膜梯度和右心室（RV）容积数据）而进一步受到削弱。需要开展新的研究，通过使用客观临床参数进行比较，以便更有效地回答我们的临床问题。
