Hình ảnh cộng hưởng từ (MRI) là kỹ thuật hình ảnh gần đây nhất trong lĩnh vực này. Thông tin hình thái và chức năng MRI có thể cung cấp là rất tương tự như siêu âm tim, với một chút ít thời gian và độ phân giải không gian hơn so với siêu âm tim Transesophageal. | Mitral regurgitation 17 Figure Three-dimensional echocardiography of a patient with prolapse of the anterior leaflet of the mitral valve. AML anterior mitral leaflet PML posterior mitral leaflet. Magnetic resonance imaging MRI is the most recent imaging technique in the field. The morphologic and functional information MRI can provide is very similar to echocardiography with somewhat lesser time and space resolution than transesophageal echocardiography. Atrial fibrillation substantially degrades image quality. Morphologic abnormalities of the leaflets can be detected as well as high-velocity regurgitant jets. Regurgitant fraction can be calculated as the difference between left ventricular inflow and outflow or between the difference of end-diastolic and end-systolic left ventricular volume on the one hand and aortic stroke volume on the other Left ventricular volumes and ejection fraction are assessed very accurately by MRI. Moreover MRI can potentially provide much supplemental information in one examination such as data on the presence and extent of myocardial scar regional perfusion and non-invasive coronary angiography which although currently rudimentary is steadily improving . While these advantages often summarized in the concept of one-stop shopping are impressive practical reasons apart from cost nowadays and most likely in the future too will prevent MRI from superseding echocardiography which will remain the first and most often also the only imaging technique needed. MRI at this time may be seen as an alternative technique if echocardiography cannot provide the necessary data. MRI can be safely performed in the presence of prosthetic valves but is hazardous in the presence of a pacemaker. Echocardiography in mitral regurgitation Mitral valve morphology Severe MR is always accompanied by morphologic abnormalities of the mitral 18 Chapter 2 valve structure or configuration. Specific morphologic assessment of the mitral valve apparatus .
