Abstract
Magnetic resonance velocity mapping was used to study the pulmonary venous flow pattern and to measure pulmonary venous flow volume in 10 normal subjects. Pulmonary venous flow showed a forward flow with two peaks, one during ventricular systole and another in diastole. A reversed flow during atrial systole was noticed. The flow pattern is understandable in relation to the dynamics of the left heart and is consistent with flow patterns obtained by other techniques. Right and left lower pulmonary venous flow was measured and corrected for body surface area. Flow (means ± SD) in the right lower pulmonary vein was 13.0 ±3.7 ml/s/m^2 and in the left 11.9 + 2.2 ml/s/m^2. Distensibility of the pulmonary veins was studied from changes in the cross-sectional areas of pulmonary veins throughout the cardiac cycle,non-significant changes were demonstrated reflecting the non-distensible nature of these vessels. Magnetic resonance imaging provides a totally noninvasive technique for qualitative and quantitative examination of pulmonary venous flow which could be of clinical value in the assessment of both cardiac and pulmonary problems.