ARTERIAL REACTIVITY IS SIGNIFICANTLY IMPAIRED IN NORMOTENSIVE YOUNG-ADULTS AFTER SUCCESSFUL REPAIR OF AORTIC COARCTATION IN CHILDHOOD

Background Despite successful repair of coarctation of the aorta in ch ildhood, adult survivors often have hypertension at rest or on exercis e, and their life expectancy is shorter than normal because of prematu re coronary and cerebrovascular disease. This may be related to persis tent structural and functional arterial abnormalities after surgery. M ethods and Results Using high-resolution ultrasound, we studied the ri ght brachial arteries of 25 normotensive young adults who had undergon e successful repair of coarctation in childhood (mean age at repair, 6 2 months; range, 0 to 167 months, including 8 patients operated on in infancy; mean age at study, 19 years; range, 14 to 27 years) and 50 ag e- and sex-matched control subjects. We assessed the degree of reactiv e hyperemia (RH) produced after distal cuff occlusion and release and the changes in arterial diameter in response to RH (with increased flo w causing endothelium-dependent dilation) and to glyceryltrinitrate (G TN, an endothelium-independent dilator). The response of the right fem oral artery to GTN was also measured in 12 coarctation subjects and 12 control subjects. Studies were performed 13.7 years (range, 7 to 21 y ears) after surgery. RH was significantly lower in coarctation subject s (343+/-130% versus 482+/-147%), as were endothelium-dependent dilati on (3.8+/-3.3% versus 8.8+/-3.6%) and GTN response (13.3+/-6.0% versus 20.5+/-6.1%) (P<.001 for each), reflecting abnormal dilatory capacity in both the resistance and conduit arteries. In contrast, GTN-induced dilation in the femoral arteries was similar to that in control subje cts (9.5+/-2.6% versus 10.1+/-4.1%, P=.70). On multivariate analysis, GTN response and systolic blood pressure at peak exercise were inverse ly correlated (r=-.52, P=.04). Vascular responses were not related to the age at repair. Conclusions Despite successful repair of coarctatio n in childhood, arterial dilation is significantly impaired in the pre coarctation vascular bed of healthy young adults. This may be an impor tant contributor to exercise-related hypertension and late morbidity o r mortality.