Introduction: Magnetic Resonance (MR) can measure physiological parameters such as stroke volume, cardiac output and ejection fraction. We have designed a fast 3D sequence to acquire volumetric data in cine mode. Methods: Using enhanced gradients, very short repetition times (TR) of approximately 5 ms can be obtained. All section-direction phase encodes are interleaved during each heart beat; in-plane phase-encoding values are updated after every heat beat. Due to the short TR values, the inherent contrast is poor. Therefore, a T1 reducing agent such as Gd-DTPA is used to provide contrast between blood and tissue. Results: The temporal resolution is similar to segmented k-space acquisitions, and the entire heart can be imaged in the same time as a traditional 2D cine scan. Excellent contrast is seen between the blood and myocardium, and the endocardial border is well visualized throughout the entire cardiac cycle. An advantage of the 3D imaging mode is that the data can be reformatted in any plane. Conclusions: . Because the signal from blood is now less dependent on flow-related enhancement, more consistent contrast between blood and myocardium can be obtained. Gadolinium-based compounds can produce some myocardial enhancement, however this can be eliminated with the use of a persistent intravascular agent.
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