Judd Robert M, Wagner Anja, Rehwald Wolfgang G, Albert Timothy, Kim Raymond J
Duke Cardiovascular Magnetic Resonance Center, Duke University, Durham, NC 27710, USA.
Nat Clin Pract Cardiovasc Med. 2005 Mar;2(3):150-8. doi: 10.1038/ncpcardio0134.
Myocardial viability is of established importance to the management of cardiac patients being considered for revascularization. Existing noninvasive imaging tests to examine myocardial viability, such as stress echocardiography and nuclear scintigraphy, are of recognized utility but are subject to intrinsic limitations. Over the past few years delayed-enhancement MRI (DE-MRI) has emerged as an alternative to traditional tests and for the first time allows direct visualization of the transmural extent of myocardial viability. In this paper we review the scientific data that underlie the use of DE-MRI in patients with ischemic heart disease. Progress in this area is largely the result of the development of a new MRI pulse sequence in the late 1990s, which improved the detection of necrotic and scarred myocardial tissue. Following this technical development, a series of detailed histologic comparisons in large animal models revealed that both acute and healed myocardial infarcts appeared as brighter (hyperenhanced) areas than viable regions, and that the effect is independent of contractile function. The resulting 'bright is dead' hypothesis has thus far proven of significant use in patients with ischemic heart disease. Data are now emerging which suggest that the DE-MRI technique also has important implications for patients with nonischemic forms of cardiomyopathy.
心肌存活性对于考虑进行血运重建的心脏病患者的治疗具有既定的重要性。现有的用于检查心肌存活性的非侵入性成像测试，如负荷超声心动图和核闪烁显像，具有公认的效用，但存在内在局限性。在过去几年中，延迟强化磁共振成像（DE-MRI）已成为传统测试的替代方法，首次能够直接观察心肌存活性的透壁范围。在本文中，我们回顾了支持在缺血性心脏病患者中使用DE-MRI的科学数据。该领域的进展很大程度上归功于20世纪90年代后期一种新的MRI脉冲序列的开发，它提高了对坏死和瘢痕化心肌组织的检测能力。随着这项技术的发展，在大型动物模型中进行的一系列详细组织学比较显示，急性和愈合的心肌梗死区域比存活区域显得更亮（高强化），并且这种效应与收缩功能无关。由此产生的“亮即坏死”假说迄今为止在缺血性心脏病患者中已被证明具有重要用途。现在有数据表明，DE-MRI技术对非缺血性心肌病患者也具有重要意义。
