Subramanian Hariharan, Kunadian Babu, Dunning Joel
Department of Cardiology, Hahneman University Hospital, Philadelphia, USA.
Interact Cardiovasc Thorac Surg. 2008 Apr;7(2):301-5. doi: 10.1510/icvts.2008.175463. Epub 2008 Jan 23.
A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether it is worth performing aortic valve replacement in patients with severe aortic stenosis and poor left ventricular function but no contractile reserve on dobutamine stress testing. Altogether 251 papers were identified using the below mentioned search and all major international guidelines were included. Fourteen presented the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group, relevant outcomes and weaknesses were tabulated. We conclude that patients with severe aortic stenosis and a contractile reserve of <20% improvement in stroke volume on dobutamine stress testing have a very poor prognosis of only 10-20% at two years. Heart transplant would offer the best chance of survival to those eligible but for those not eligible, a surgical option should not be discounted for selected patients. The American Heart Association guidelines state that prognosis is very poor for either medical or surgical treatment, but the European Society of Cardiology guidelines state that surgery can be performed in these patients but should take into account the clinical condition of the patient. The operative mortality is around 30% and the French Multicentre study on low gradient aortic stenosis has shown that if the patient survives there is likely to be an improvement in symptoms and ejection fraction. Thus, absence of contractile reserve on stress testing does not exclude myocardial recovery after surgery, although it is a strong predictor for operative mortality. It should be noted that surgery has only been reported in very few of these patients to date. B-natriuretic peptide has also been suggested as a further marker of better prognosis in these high-risk patients in one small study.
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，对于重度主动脉瓣狭窄且左心室功能较差但多巴酚丁胺负荷试验无收缩储备的患者，进行主动脉瓣置换术是否值得。通过下述检索共识别出251篇论文，并纳入了所有主要的国际指南。14篇论文提供了回答该临床问题的最佳证据。将作者、期刊、发表日期、国家、患者群体、相关结局及不足之处制成表格。我们得出结论，对于重度主动脉瓣狭窄且多巴酚丁胺负荷试验时每搏量改善的收缩储备<20%的患者，其两年预后极差，仅为10% - 20%。心脏移植会为符合条件者提供最佳的生存机会，但对于不符合条件者，不应排除为部分患者选择手术治疗。美国心脏协会指南指出，药物或手术治疗的预后均很差，但欧洲心脏病学会指南指出，这些患者可以进行手术，但应考虑患者的临床状况。手术死亡率约为30%，法国关于低梯度主动脉瓣狭窄的多中心研究表明，如果患者存活，症状和射血分数可能会改善。因此，负荷试验时无收缩储备并不排除术后心肌恢复，尽管它是手术死亡率的一个强有力预测指标。应当指出，迄今为止，仅对极少数这类患者进行过手术报道。一项小型研究还提出，B型利钠肽可作为这些高危患者预后较好的进一步标志物。
