Hartiala J, Knuuti J
Department of Clinical Physiology, Turku Cyclotron-PET Center, Turku University Hospital, Finland.
Ann Med. 1995 Feb;27(1):35-45. doi: 10.3109/07853899509031934.
This review article describes the clinical usefulness and future potential of two new methods for the imaging of the heart, which have recently also become available outside research laboratories. These methods are magnetic resonance imaging (MRI) and positron emission tomography (PET). MRI is the most rapidly increasing imaging modality in medicine today. The moving heart forms a challenge to conventionally rather slow MRI-techniques. Techniques based on ECG-gating have been mandatory in making cardiac cine-MRI possible. Even though MRI provides accurate and quantitative information of the heart, conventional methods are time-consuming, confined to special laboratories, and rather expensive. Therefore, the clinical use of cardiac MRI is, in many laboratories, limited to cases in which echocardiography does not provide adequate information (e.g. pulmonary circulation) or when the patient is not willing to have transoesophageal echocardiography for better visibility. MRI is also used instead of or to complement invasive angiography to study large vessels, and it provides excellent information on paracardiac masses. Cardiac MRI is developing rapidly and within the next few years it is likely to have a profound impact on cardiac imaging. This is based on its noninvasive nature and on the comprehensive anatomic (including coronary arteries), functional, flow, perfusion and possibly also metabolic information it has the potential to provide in a manner not comparable to any other imaging method. PET is a nuclear medicine imaging modality that allows quantitative characterization of a variety of physiological and metabolic processes in vivo. Using positron-emitting flow tracers and analogues of metabolic substrates, regional myocardial blood flow, glucose and fatty acid metabolism and oxygen consumption can be studied noninvasively by PET in research as well as in clinical practice. For example, regional myocardial glucose utilization rates can be measured accurately by PET. This allows us to study the effects of nutritional interventions, hormonal and neural effects as well as disease processes on the glucose utilization of the human heart. PET is currently the only technique that permits noninvasive quantification of regional myocardial perfusion in absolute terms. Over the last decade, PET has also emerged as a clinically useful tool to study coronary artery disease and myocardial viability.
这篇综述文章描述了两种用于心脏成像的新方法的临床实用性和未来潜力，这两种方法最近也已在研究实验室之外得到应用。这些方法是磁共振成像（MRI）和正电子发射断层扫描（PET）。MRI是当今医学领域中增长最为迅速的成像方式。跳动的心脏对传统上相对较慢的MRI技术构成了挑战。基于心电图门控的技术对于实现心脏电影MRI至关重要。尽管MRI能提供关于心脏的准确且定量的信息，但传统方法耗时、局限于特殊实验室且成本高昂。因此，在许多实验室中，心脏MRI的临床应用仅限于超声心动图无法提供足够信息的情况（如肺循环），或者患者不愿意接受经食管超声心动图以获得更好的可视性时。MRI还被用于替代或补充有创血管造影来研究大血管，并且它能提供关于心外肿块的出色信息。心脏MRI发展迅速，在未来几年内可能会对心脏成像产生深远影响。这基于其非侵入性本质以及它有潜力以一种与任何其他成像方法都不可比的方式提供全面的解剖（包括冠状动脉）、功能、血流、灌注以及可能还有代谢信息。PET是一种核医学成像方式，可对体内多种生理和代谢过程进行定量表征。通过使用正电子发射血流示踪剂和代谢底物类似物，PET可在研究以及临床实践中对局部心肌血流、葡萄糖和脂肪酸代谢以及氧消耗进行非侵入性研究。例如，PET可准确测量局部心肌葡萄糖利用率。这使我们能够研究营养干预、激素和神经效应以及疾病过程对人类心脏葡萄糖利用的影响。PET是目前唯一能够绝对地对局部心肌灌注进行非侵入性定量的技术。在过去十年中，PET也已成为研究冠状动脉疾病和心肌存活的一种临床有用工具。
