The usefulness of continuous Doppler in the diagnosis of aortic coarctation

: Were studied 32 patients with coarctation of the aorta by continuous wave Doppler ultrasound in order to assess the usefulness of this diagnostic method. Nineteen (59%) had native coarctation and 13 (41%) recoarctation. Seventeen (53%) were male and 15 (47%) female. The mean age when diagnosis was performed was 56 +/- 54 months. We found associated anomalies in 15 patients (46%). We studied 5 variables of the continuous Doppler curve at the descending aorta that were compared with those of a control group of 20 patients without cardiac anomalies. The variables were: peak systolic gradient (50.1 +/- 18 mmHg; VS 7.6 +/- 3 mmHg; p = 0.001); peak diastolic gradient 18.5 +/- 10 mmHg; VS 0.49 +/- 0.5 mmHg; p = 0.001; systolic velocity half time 151.5 +/- 40 msec; VS 102 +/- 17 msec; p = 0.01; diastolic velocity half time 132.2 +/- 82 msec; VS 7 +/- 14 msec; p = 0.001 corrected acceleration time (169 +/- 26 mmHg; VS 138 +/- 22 mmHg; p = 0.01). Systolic gradient was highly sensitive (100%) and specific (100%). Diastolic gradient and time to half peak diastolic velocity were very specific (100%) and less sensitive (93% and 62%). There were 6 false positive and 4 false negative when we used the time to half peak systolic velocity (sensitivity 81%, specificity 72%). We conclude that continuous Doppler is a useful method in the diagnosis of coarctation of the aorta. The most important variables of Doppler curve are systolic gradient, diastolic gradient and time to half peak diastolic velocity. All patients with coarctation of aorta had at least 2 variables altered.