Blood flow patterns in the thoracic aorta studied with three-directional MR velocity mapping: the effects of age and coronary artery disease.

The objective was to investigate how the blood flows in the thoracic aorta, with special emphasis on flow reversal and flow into the coronary arteries. Three-directional MR velocity mapping was used to map multidirectional flow velocities in the aorta in 14 normal subjects and 14 patients with coronary artery disease. Dynamic flow vector maps and through-plane velocity maps were used. The flow reversed in all subjects in the upper ascending aorta and usually also in the distal aortic arch. Retrograde flow became antegrade again at various levels in the ascending aorta and in the coronary sinuses. Seven flow characteristics were investigated that, lumped together, were significantly different (P = .0005) in normal subjects compared with patients and in normal subjects 70 years of age and older compared with those younger than 70 years of age.