DEMONSTRATION OF FETAL CORONARY BLOOD-FLOW BY DOPPLER ULTRASOUND IN RELATION TO ARTERIAL AND VENOUS FLOW VELOCITY WAVE-FORMS AND PERINATAL OUTCOME - THE HEART-SPARING EFFECT

This longitudinal observational study evaluates the stage at which cor onary flow can be visualized by color-coded and pulsed wave Doppler so nography in fetuses with normal cardiac anatomy. Fetal biometry, echoc ardiography and Doppler examination of the umbilical and middle cerebr al arteries, ductus venosus, inferior vena cava and umbilical vein wer e performed in 109 cases. Fetuses were divided into five groups based on the Doppler examination of the umbilical artery, birth weight and t he ability to visualize coronary blood flow. Coronary blood flow was i dentified in six of 55 fetuses with normal growth who had normal Doppl er studies and perinatal outcome. In these, visualization of coronary blood flow was possible after 31 weeks' gestation at a median gestatio nal age of 37 weeks. Coronary blood flow was also visualized in ten of 54 fetuses with severe intrauterine growth retardation and highly pat hological flow velocity waveforms in all vessels soon after a signific ant increase of venous indices in She inferior vena cava and ductus ve nosus. In these cases, coronary blood flow was identified at a signifi cantly earlier gestational age (median 27 weeks). These fetuses had a poor perinatal outcome (average birth weight less than 3rd centile, mo rtality rate 50%, significantly lower umbilical artery blood pH and Ap gar scores after 1 and 5 min). Intrauterine fetal death occurred in fi ve fetuses after a median of 3.5 days following visualization of coron ary blood flow. Median coronary peak blood flow velocities in the righ t coronary artery were higher in intrauterine growth-retarded than app ropriate-for-gestational-age fetuses.