Estimation of total coronary artery flow using measurements of flow in the ascending aorta.

This paper describes a technique for estimation of total (right+left) coronary artery flow using MRI flow measurements in the ascending aorta. The technique is based on the principle that the flow in a vessel branch is equal to the difference of the net flow measured above and below the branch ostia. Aortic net flow is measured at four or more axial oblique slices from below the aortic valve to above the highest location of the coronary vessel ostia in late diastole. A flow model properly interprets the flow measurements in slices that contain the coronary ostia. Results in five normal subjects show that total coronary artery flow can be measured with a standard error of about 90 cc/min, 30% of total coronary artery flow. Potential clinical uses include noninvasive measurement of coronary flow reserve. Pulse sequence improvements are necessary to reduce examination time and improve accuracy and precision.