Types
There are three types:
- Preductal coarctation: The narrowing is proximal to the ductus arteriosus. Blood flow to the aorta that is distal to the narrowing is dependent on the ductus arteriosus; therefore severe coarctation can be life-threatening. Preductal coarctation results when an intracardiac anomaly during fetal life decreases blood flow through the left side of the heart, leading to hypoplastic development of the aorta. This is the type seen in approximately 5% of infants with Turner Syndrome.
- Ductal coarctation: The narrowing occurs at the insertion of the ductus arteriosus. This kind usually appears when the ductus arteriosus closes.
- Postductal coarctation: The narrowing is distal to the insertion of the ductus arteriosus. Even with an open ductus arteriosus blood flow to the lower body can be impaired. This type is most common in adults. It is associated with notching of the ribs (because of collateral circulation), hypertension in the upper extremities, and weak pulses in the lower extremities. Postductal coarctation is most likely the result of the extension of a muscular artery (ductus arteriosus) into an elastic artery (aorta) during fetal life, where the contraction and fibrosis of the ductus arteriosus upon birth subsequently narrows the aortic lumen.
Read more about this topic: Coarctation Of The Aorta
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