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.

点击翻译按钮获取中文摘要

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.