Abdominal Aortic Pulsed Wave Doppler Patterns Reliably Reflect Clinical Severity in Patients with Coarctation of the Aorta

OBJECTIVE: There are situations in which standard echocardiography does not adequately define the aortic arch. We sought to determine what additional information could be gained by analyzing abdominal aortic Doppler flows in coarctation. DESIGN: Previously recorded echocardiographic data were reviewed in 70 controls and 248 patients with coarctation, including abdominal aortic values for pulsatility indices, pulse delay, and presence of early diastolic reversal. Ability of these variables to distinguish controls from coarctation patients and to assess coarctation severity was assessed. RESULTS: Corrected maximum instantaneous gradient and all abdominal aortic flow variables were associated with severity of obstruction. Early diastolic reversal was universally absent in significant coarctation. Threshold values for other parameters associated with significant obstruction were: corrected pulse delay >or=3.4 msec(1/2), pulsatility index <2.0, and systolic to diastolic velocity ratio <3.6. A combined abdominal aortic "variable" (absence of early diastolic reversal and corrected pulse delay >or=2.8 msec(1/2)) was found to be the best predictor of clinical coarctation status (positive predictive value = 93%, negative predictive value = 88%). CONCLUSIONS: In the absence of a ductus arteriosus, abdominal aortic Doppler parameters can reliably predict the presence of significant coarctation. When early diastolic reversal was present, obstruction was always absent. Lack of early diastolic reversal with a prolonged pulse delay was the best predictor of significant obstruction. Abdominal aortic Doppler evaluation should become a routine part of the evaluation of patients with known or suspected coarctation.