1. Apparatus for producing an MR angiographic image of a slice of interest in a living patient in such a manner that the image is not degraded by regurgitated bloodflow, comprising: means for establishing a saturation slab adjacent the slice of interest; means for monitoring the patient's cardiac cycle; means for eliminating said slab for a predetermined period of time after maximum unregurgitated bloodflow rate has commenced; and means restoring said slab to its original position adjacent the slice of interest after regurgitated bloodflow has ceased.