Doppler ultrasound and magnetic resonance for evaluation of patients treated surgically for aortic coarctation

Doppler ultrasound and magnetic resonance were performed in a series of 39 patients who had been treated surgically for aortic coarctation. The purpose was to assess the different Doppler gradients, comparing the findings with morphological data disclosed by magnetic resonance. The aortic caliber in the operative field was pathological in 7 patients (ratio between the caliber at the level of the lesion and that of descending aorta of less than 0.7). When the patients were considered as a group. Doppler ultrasound did not show satisfactory sensitivity (29%-43%), specificity (74%) or positive predictive value (17%-23%). Only the negative predictive value (85%-88%) presented more favorable results. When the Subgroup of patients without associated cardiac abnormalities or collateral circulation was studied alone, the following results were found: sensitivity, 100%; specificity, 81%-90%, positive predictive value, 33%-50%, negative predictive value, 100%, similar to those reported in the literature. Thus, we consider that Doppler ultrasound is a harmless and low cost diagnostic method that is highly suitable for follow-up of these patients, within certain limits. Magnetic resonance is the method of choice for the noninvasive assessment of aortic morphology. (Author)