In patients successfully operated for coarctation of the aorta, the prevalence of hypertension is higher than that observed in the general population although the exact mechanism is not known. The hypothesis of increased arterial rigidity despite satisfactory correction of the coarctation has been proposed. The authors undertook 24 hour ambulatory blood pressure monitoring coupled with measurement of the QKD interval (pulse wave velocity) in order to evaluate the rigidity of the large arteries. These results were compared with those obtained in control patients paired with respect to gender, age, height and weight. Twenty-six patients with an average age of 14.5 +/- 2.9 years were included (age at time of surgery 6.3 +/- 3.7 years). The statistical data confirmed a higher systolic blood pressure (p<0.05) in the operated patients compared with controls. The results confirm the hypothesis of increased residual arterial rigidity in children operated for coarctation of the aorta which could predispose to secondary hypertension, especially on effort. In the long term, this could be an unquestionable cardiovascular risk factor explaining the increased cardiovascular morbid-mortality compared with the general population.