Restricted blood flow in the abdominal aorta at rest and exercise in patients after coarctation aortae repair despite correction

Abstract

Purpose: Anatomic measurements and blood pressure differences in rest are currently used to determine whether patients after aortic repair for coarctation have a recoarctation or not. Whether flow patterns in the abdominal aorta at rest and during exercise are of additional value in determining functional restriction of the former coarctation side is unknown. Therefore, we investigated Doppler flow patterns in the abdominal aorta compared these with normal volunteers. Methods: We included random patients after aortic coarctation repair without significant re-coarctation on MRI, or uncontrolled hypertension. All patients underwent a rest echocardiography and a bicycle exercise test with echocardiographic examination limited to 70% of the predicted heart rate. Echocardiography was performed according to international recommendations. The systolic diastolic ratio (S/D) was measured in the abdominal aorta. The pulse delay was the difference of the time measured from R-wave until peak velocity in the left ventricular outflow tract and the abdominal aorta. Ten random healthy volunteered controls underwent the similar protocol. Results: Twenty adult patients were included (10 males, mean age 38 years±5) and 10 healthy controls (4 males, mean age 41 years± 10). The maximum flow velocity in the descending aorta was significantly higher than in healthy volunteers. The S/D ratio at rest was similar for both patient groups, but differed significantly at exercise. The pulse delay was significantly larger in coarctation patients than in controls. All parameters indicate a abnormal arterial systemic flow pattern below the coarctation site. View this table: Conclusion: Patients after coarctation without clinical recoarctation have very abnormal flow patterns in the post coarctation aorta, especially during exercise. Further research is needed to determine whether this is clinical meaningful and whether other definitions of recoarctation should be formulized.