Development of a real-time quantitative Magnetic Resonance Imaging (MRI) flow measurement of cardiac valves and great thoracic vessels in normal volunteers and in patients with valvular heart disease or shunts.

该项目旨在开发和验证一种使用实时磁共振成像（MRI）进行定量二维流量测量的新方法。这项新技术允许使用动态相位对比技术在高空间分辨率和实时下进行定量流量MRI测量，而不需要ecg门控或重复暂停呼吸。特别是对于心律失常患者或危重患者，这种实时方法的实际时间分辨率为37 ms，将提供可靠的二维血流测量，这是目前建立的方法无法实现的。进行生理压力测试的能力，如增加（valsalva机动）或减少胸内压力将被评估。预期的结果可能会给心脏病理生理学提供新的见解，因为MRI是唯一能够通过血管的完整横截面分析血流的方法。工作计划还包括对正常志愿者、心律失常患者以及瓣膜性心脏病、心脏分流或全身血管分流患者进行验证试验。技术方面将包括这种实时MRI方法的相位偏移伪影的发生，特别是在肺近端干的关键位置。在这个为期三年的研究项目中，我们的目标是建立一个可用于前瞻性临床试验的实时二维流量测量方案。

This project aims at the development and validation of a novel approach for quantitative 2D flow measurements using real-time magnetic resonance imaging (MRI). The new technique allows for quantitative flow MRI measurements using a dynamic phase-contrast technique at high spatial resolution and in real time, that is without the need of ECG-gating or repetitive suspended respiration. Especially in patients with arrhythmia or in the critically ill patient this real-time approach with an actual temporal resolution of 37 ms will provide reliable 2D flow measurements that are not feasible with currently established methods. The ability to perform physiologic stress tests such as an increase (valsalva manoeuvre) or decrease of the intrathoracic pressure will be evaluated. The expected results may give new insights into cardiac pathophysiology as MRI is the only method capable of analysing the blood flow through the complete cross-section of a vessel. The working program also includes validation tests with normal volunteers, patients with arrhythmia as well as patients with valvular heart disease, shunts within the heart or systemic vascular shunts. Technical aspects will include the occurrence of phase offset artefacts with this real-time MRI approach especially in the critical position of the proximal pulmonary trunk. As a result of this three-year research program we aim to establish a protocol for real-time 2D flow measurements that can be used in prospective clinical trials.