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新的方法，用于使用实时磁共振成像（MRI）进行定量2D流量测量。新技术允许使用动态相位对比技术以高空间分辨率和真实的时间进行定量流动MRI测量，即不需要ECG门控或重复暂停呼吸。特别是在心律失常患者或重症患者中，这种实际时间分辨率为37 ms的实时方法将提供可靠的2D血流测量，而目前建立的方法是不可行的。 将评价进行生理负荷试验的能力，如胸内压升高（valsalva动作）或降低。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是唯一能够分析通过血管完整横截面的血流的方法。该工作计划还包括对正常志愿者、心律失常患者以及心脏瓣膜病、心脏内分流或全身血管分流患者进行验证测试。技术方面将包括这种实时MRI方法的相位偏移伪影的发生，特别是在近端肺动脉干的关键位置。作为这项为期三年的研究计划的结果，我们的目标是建立一个实时2D流量测量，可用于前瞻性临床试验的协议。

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.