Coarctation of the Aorta: Causes, Symptoms, and Treatment

Coarctation of the aorta is a congenital heart defect characterized by a narrowing of the aorta, the main artery carrying oxygen-rich blood from the heart to the rest of the body. This narrowing forces the heart to pump harder to move blood through the constricted vessel. The severity can vary, leading to a wide range of effects, from mild issues that go unnoticed until adulthood to severe problems that appear shortly after birth. The narrowing most often occurs just after the point where the left subclavian artery branches off to supply the left arm.

Causes and Associated Conditions

The precise cause of coarctation of the aorta is often unknown, but it is a congenital defect that arises from an error during fetal heart development. Genetic factors can contribute, and the condition is more common in males than females.

This aortic narrowing frequently appears alongside other heart abnormalities. A bicuspid aortic valve, where the valve has two leaflets instead of the usual three, is commonly found in individuals with coarctation. Other associated conditions include a ventricular septal defect (VSD), a hole in the wall separating the heart’s lower chambers, and Turner syndrome.

Signs and Diagnosis

The signs of coarctation of the aorta depend on the severity of the narrowing and the patient’s age. In newborns with a significant constriction, symptoms can appear within the first few weeks of life and include:

• Pale skin
• Heavy sweating
• Irritability
• Difficulty breathing

These infants may also exhibit poor feeding and inadequate weight gain. In older children and adults with milder cases, the condition might not be discovered until a routine physical exam. A key indicator is high blood pressure in the arms, while blood pressure in the legs is normal or low. This can lead to:

• Headaches
• Nosebleeds
• Leg cramps
• Cold feet, particularly during exercise

The body may create new blood vessels, known as collaterals, to bypass the narrowed area.

Diagnosis begins with a physical exam, where a doctor detects a difference in pulse strength and blood pressure between the arms and legs. The primary tool for confirmation is an echocardiogram, an ultrasound that shows the heart’s structure and reveals the narrowing’s location and severity. Additional imaging like CT scans or MRI may be used for a more comprehensive view of the aorta.

Treatment Approaches

The objective of treatment is to relieve the obstruction in the aorta, restoring proper blood flow to the lower part of the body. The specific approach is chosen based on the patient’s age, the anatomy of the coarctation, and its severity. For many infants and complex cases, surgery is the preferred method. This procedure involves removing the narrowed segment of the aorta and sewing the two healthy ends back together, a technique known as resection with end-to-end anastomosis.

A less invasive option is balloon angioplasty, often used for re-narrowing or in older children and adults. In this procedure, a thin tube with a deflated balloon at its tip is guided through a blood vessel to the coarctation site. The balloon is then inflated, stretching the narrowed artery open to improve blood flow.

In some cases, particularly in adults or when angioplasty alone is not sufficient, a stent may be placed. A stent is a small, expandable mesh tube positioned within the narrowed area during an angioplasty. It acts as a scaffold to hold the artery open and ensure it remains wide enough for blood to pass through freely.

Long-Term Management and Outlook

After a successful repair, lifelong monitoring by a cardiologist is required to ensure the aorta remains open and manage any related health issues. These check-ups involve physical exams, blood pressure measurements in all four limbs, and periodic imaging studies like echocardiograms, MRIs, or CT scans to assess the repaired site.

One of the primary long-term concerns is the potential for the aorta to narrow again, a condition called re-coarctation, with the highest risk in patients treated as newborns. Another significant issue is hypertension, as high blood pressure can persist or develop years after the repair, often requiring medication and lifestyle adjustments. With proper follow-up care, most individuals treated for coarctation of the aorta lead full and active lives.