Pulmonary blood flow and left ventricular volumes in transposition of the great arteries and intact ventricular septum.

Pulmonary blood flow and left ventricular volumes were determined angiographically from 33 studies on 30 patients (2I male, 9 female) with transposition of the great arteries and intact ventricular septum. Twelve of the studies were performed on infants under 2 months of age (median age 33 hours). The pulmonary blood flow in this group ranged from I 3 to 4 8 (mean, 3 0) 1./min/m2. There were 21 studies on patients over 2 months of age (median age I6 months) with a pulmonary blood flow ranging from 3 9 to II -3 (mean= 6 4) l./min/m2. This difference in mean pulmonary bloodflow was statistically significant (P< o-ooi). Left ventricular end-diastolic volume rangedfrom I2 to 39 (mean, 3I) ml/m2 in those under 2 months of age andfrom 30 to II6 (mean, 70) ml/m2 in those over this age. Left ventricular mass rangedfrom I5 to 35 (mean, 28) g/m2 for those under 2 months of age and increased with increasing pulmonary bloodflow. For the older group, it rangedfrom 32 to i5o (mean, 69) g/m2 and showed a positive correlation with both pulmonary blood flow and left ventricular systolic pressure. The ejection fraction did not change with age and ranged from 0-57 to o 85 (mean, 0.73) for the whole group. In 8 patients, aged 9 months to 4years (median age, 24J years), oxygen consumption was measured; pulmonary bloodflow as estimated by the Fick method in these rangedfrom 6i2 to I4i9 (mean, Io.4) 1./minIm2. This was appreciably higher than thefigures 3 9 to 8-7 (mean, 6 .5) .L/min/M2 obtained by the angiographic method during the same study.